WO2016116473A1

WO2016116473A1 - Oil/oil emulsion containing microparticles comprising at least two different materials, each being organic or mineral

Info

Publication number: WO2016116473A1
Application number: PCT/EP2016/051056
Authority: WO
Inventors: Léonora HENAULT-MEZAIZE; Cécile TOULOUZAN; Florence Levy
Original assignee: L'oreal
Priority date: 2015-01-21
Filing date: 2016-01-20
Publication date: 2016-07-28
Also published as: FR3031674A1; FR3031674B1

Abstract

The present invention relates to an oil/oil (O/O) emulsion comprising at least: - a first oily phase comprising at least a first non-volatile oil chosen from silicone oils, hydrocarbon-based oils and fluoro oils, - a second oily phase comprising at least a second non- volatile or volatile oil, which is immiscible with the first oil(s), at 25°C, and - solid microparticles having at least one curved part whose radius of curvature is not infinite, the largest dimension of which is at least 0.15 μm, and comprising at least two different materials, each organic or mineral. The invention also relates to a cosmetic composition comprising, in a physiologically acceptable medium, at least one oil/oil emulsion in accordance with the invention, and also to the use of solid microparticles having at least one curved part whose radius of curvature is not infinite, the largest dimension of which is at least 0.15 μm, and comprising at least two different materials, each being mineral or organic, for stabilizing an O/O emulsion.

Description

"Oil/oil emulsion containing microparticles comprising at least two different materials, each being organic or mineral"

The present invention relates to the field of cosmetic compositions based on oil/oil (O/O) emulsions.

There is still a need for novel architectures leading to stable cosmetic compositions that have the comfort properties required by users.

The authors of the present invention have oriented their research towards 0/0 emulsions. These emulsions are relatively uncommon, but nevertheless have the advantage of having novel properties.

The main problem posed by this type of emulsion is associated with its stability: 0/0 emulsions are generally stabilized with gelling agents or even emulsifying surfactants and/or (co)polymers.

This type of emulsion is used in particular in lipcare and/or lip makeup products. For example, patent application WO 2009/150 852 is directed towards an oil-in- oil cosmetic composition comprising a hydrocarbon-based non- volatile oil, a silicone nonvolatile oil and a fatty acid ester of dextrin; said application does not describe O/O emulsions of Pickering type.

Surprisingly and advantageously, the authors of the present invention have used O/O emulsions of Pickering type stabilized with solid particles, which particles, furthermore, are not nanoparticles. The emulsions according to the invention comprise two different immiscible oily phases, one forming the continuous phase and the other forming the dispersed phase, and particular solid particles for stabilizing the emulsion by positioning themselves at the interface of the dispersed and continuous phases.

Once positioned at the interface, the solid particles "block" the dispersed phase, which leads to stabilization of the emulsion. The O/O emulsion thus formed is stable for several weeks.

The emulsion according to the invention also makes it possible to dispense with the use, as stabilizers, of compounds of surfactant type, especially synthetic surfactants, and/or of gelling agents, since some of these agents may present toxicity risks to the environment depending on the amounts used. In addition, in the context of the invention, the oils used for forming the two phases may be judiciously chosen as a function of the intended use of the final product and of the desired properties.

Thus, a first subject of the invention is directed towards an oil/oil (O/O) emulsion comprising at least:

- a first oily phase comprising at least a first non-volatile oil chosen from silicone oils, hydrocarbon-based oils and fluoro oils,

- a second oily phase comprising at least a second non-volatile or volatile oil, which is immiscible with the first oil(s), at 25°C, and

- solid microparticles having at least one curved part whose radius of curvature is not infinite, the largest dimension of which is at least 0.15 μιη, and comprising at least two different materials, each organic or mineral.

The invention is also directed towards a cosmetic composition comprising, in a physiologically acceptable medium, at least one O/O emulsion according to the invention.

Definitions

The term "room temperature" is intended to denote a temperature of about 25°C, for example ranging from 18 to 25°C. It is set at atmospheric pressure (i.e. a pressure of 1.013 x 10⁵ Pa).

The compositions and/or emulsions according to the invention comprise a physiologically acceptable medium, i.e. a non-toxic medium that can be applied to human skin, and which is of pleasant appearance, odour and feel.

According to a preferred embodiment, the composition according to the invention is a solid composition.

According to another preferred embodiment, the composition according to the invention is a liquid composition.

In particular, it is a cosmetic composition for caring for and/or making up the skin, and more particularly facial skin, or alternatively a composition for treating keratin fibres.

The term "skin" is intended to denote all of the skin of the body, including the lips, and preferably the skin of the face, the neck and the neckline, and also the lips.

The term "keratin fibres" more particularly means the hair. More specifically, the composition according to the invention is a composition chosen from lip makeup products, antisun products, deodorants, care products and fragrances.

In a known manner, the cosmetic composition of the invention may also contain adjuvants that are common in cosmetics, such as lipophilic gelling agents, preserving agents, fragrances, fillers, UV-screening agents, which are especially lipophilic, bactericides, odour absorbers, dyestuffs, plant extracts, antioxidants and nonionic, anionic, cationic or amphoteric surfactants.

The amounts of these various adjuvants are those conventionally used in the field under consideration, for example from 0.01 to 20% of the total weight of the composition. Depending on their nature, these adjuvants may be introduced into the first oily phase and/or into the second oily phase.

According to another subject, the invention is directed towards the use of solid microparticles having at least one curved part whose radius of curvature is not infinite, the largest dimension of which is at least 0.15 μιη and comprising at least two different materials, each mineral or organic, for stabilizing an O/O emulsion comprising at least a first oily phase comprising at least a first non-volatile oil chosen from silicone oils, hydrocarbon-based oils and fluoro oils, and at least a second oily phase comprising at least a second volatile or non-volatile oil that is immiscible with the first oil(s) at 25°C.

Solid particles

The solid microparticles that may be used for stabilizing the O/O emulsion according to the invention thus have at least one curved part whose radius of curvature is not infinite.

For the purposes of the present invention, the term "radius of curvature" does not cover the "infinity" value "∞"; thus, the microparticles used according to the invention are not in the form of platelets or leaflets.

The solid microparticles in accordance with the invention may be filled or hollow. They may also be smooth or rough.

According to a particular form of the invention, the largest dimension of the composite microparticles of the invention is preferably, on average, between 0.15 and 100 μιη, more particularly between 0.2 and 50 μιη, more particularly from 0.4 to 30 μιη, preferably between 0.5 and 20 μηι; or even from 1 to 10 μιη, for example from 2 to 7 μιη. The largest dimension of the particles, which corresponds to a mean dimension on 50% by volume of the particles, may be determined using a laser diffraction granulometer (e.g. Mastersizer 2000 from the company Malvern).

According to a particular embodiment, the solid microparticles contain at least two curved parts.

According to a first variant, the solid microparticles that may be used in the present invention comprise several curvatures.

The term "several curvatures" means curvatures of different radius. In particular, the solid microparticles that may be used in the present invention comprise at least one concave part and at least one convex part.

More particularly, the microparticles in accordance with this variant have a form chosen from forms of "bowl", "golf ball" and "polytope" type.

According to a second variant, the solid microparticles that may be used in the present invention comprise only one curvature. For the purposes of the invention, the term "only one curvature" means that when the microparticle comprises several curves, these curves have curvatures of the same radius.

They may thus be chosen from hemispherical, fusiform microparticles, for example of "rugby ball" type.

According to a particular, preferred embodiment of the invention, the solid microparticles in accordance with the invention are spherical.

The term "spherical" means that the particle has a sphericity index, i.e. the ratio between its smallest diameter and its largest diameter, of between 0.8 and 1.

In this case, the largest dimension of said microparticles corresponds more particularly to the "mean particle diameter". This mean diameter may be indicated on 50% by volume of the particles (D[0,5]) obtained using a laser diffraction granulometer (e.g. Mastersizer 2000 from the company Malvern).

As will emerge on reading the text hereinbelow, the solid microparticles may have various structures. In other words, the arrangement of the at least two materials included in the microparticles may vary.

Thus, one subject of the invention is an oil/oil (O/O) emulsion according to any one of the attached claims, in which (i) the microparticles comprise a core comprising at least a first material; said core being covered at the surface, continuously or discontinuously, with an envelope comprising at least a second material different from the first, or alternatively (ii) at least a second material is dispersed in a matrix of at least a first material different from the second material(s).

More particularly, the composite particles in accordance with the invention comprise a core comprising at least a first material; said core being covered at the surface, continuously or discontinuously, with an envelope (or shell) comprising at least a second material different from the first. In addition, the envelope may comprise particles of the second material(s).

According to a first embodiment, the composite particles in accordance with the invention comprise a core comprising at least a first material covered with an envelope

(or shell) of at least a second material different from the first, said envelope being continuous, i.e. surrounding the entire surface of the core.

According to a second embodiment, the composite particles in accordance with the invention comprise a core comprising at least a first material covered with an envelope

(or shell) of at least a second material different from the first, said envelope being discontinuous, i.e. discontinuously surrounding the surface of the core.

Preferentially, from 10% to 90%, more particularly from 10% to 70% and even more particularly from 30% to 50% of the surface of the core is covered with the envelope.

Alternatively, use may also be made of particles in which the second material(s) are dispersed in a matrix of at least a first material different from the abovementioned second material(s).

Preferentially, the weight ratio of the first material(s) (i.e. the material(s) constituting the core of the particles or the matrix) to the weight of the second material(s) (constituting the envelope or the encapsulated material(s)) ranges from 70/30 to 99.9/0.1, more preferentially from 80/20 to 99/1 and even more particularly from 90/10 to 99/1.

The microparticles according to the invention are moreover such that a stable emulsion is obtained by using 5% of microparticles in a mixture comprising 47.5% of castor oil (castor oil Codex, sold by Interchimie) and 47.5% of polydimethylsiloxane oil (Dow Corning® 200 Fluid 100 cSt, sold by Dow Corning) with at least one of the following two procedures, each performed at 20°C and atmospheric pressure: 1) Rayneri blender (LG335 rotor/stator emulsifying machine; Reference B00141638 from the company VMI Rayneri; rotor diameter 25 mm - stator height 30 mm); process performed with 80 g of mixture, for 5 minutes at 1 150 rpm with only the oils, then for 5 minutes at 1150 rpm with the oils and the microparticles.

2) Ultrasonication (Sonicator XL machine from Misonix Incorporated); process performed with 20 g of mixture for 30 seconds with the two oils, then 30 seconds with the two oils and the microparticles, with a power of 165 W.

Moreover, the term "stable emulsion" is intended to denote emulsions for which at least 50% by volume of dispersed phase remains in the form of drops, more particularly at least 70% by volume, preferably at least 80% by volume, after 24 hours at 20°C and atmospheric pressure.

Observation of the phase remaining dispersed is performed in two ways:

1) its volume is evaluated by placing the emulsion in a graduated container directly after preparing it, and the volume of phase separated out after 24 hours of storage is evaluated.

2) the dispersed phase is observed using a DMLB100 Leica light microscope with a x lO objective lens, to check for the presence of the oil droplets.

The materials constituting the microparticles according to the invention are more particularly chosen from hydrocarbon-based and silicone polymers, or from mineral compounds; the microparticles comprising at least two different materials; the microparticles being satisfactory for obtaining a stable emulsion as described previously.

More particularly, the materials included in the composition of the composite particles according to the invention may be chosen from the following compounds, in particular on condition that at least two different materials are present and that the particles satisfy the conditions for obtaining a stable emulsion indicated previously:

(i) crosslinked or non-crosslinked poly(meth)acrylate and polyalkyl (meth)acrylate (co)polymers,

(ii) crosslinked organopolysiloxane elastomers,

(iii) polysaccharides, in particular natural polysaccharides or polysaccharides of natural origin,

(iv) polyamides, (v) copolymers of styrene and of (meth)acrylic acid or a (Ci-C2o)alkyl ester thereof under the INCI name: Styrene/ Acrylates Copolymer, polystyrene,

(vi) polyorganosilsesquioxanes, more particularly polymethyl-silsesquioxanes,

(vii) mineral particles chosen more particularly from metal oxides, silicates, glass particles, silica, calcium carbonate, magnesium carbonate, magnesium hydrogen carbonate, hydroxyapatite, boron nitride, and alkali metal sulfates and phosphates; bismuth oxychloride,

(viii) cationic polymers,

(ix) poly-P-alanine, polyurea,

(x) polyethylene; polyethylene (meth)acrylate, polypropylene, polytetrafluoroethylene (Teflon®), polyurethanes; expanded hollow particles of vinylidene chloride and acrylonitrile polymer, and

(xi) mixtures thereof. Preferably, among the materials that can constitute the core (or matrix) of the microparticles according to the invention, mention may be made of:

(i) crosslinked or non-crosslinked poly(meth)acrylate and polyalkyl (meth)acrylate polymers,

(ii) crosslinked organopolysiloxane elastomers,

(iv) polyamide particles,

(v) particles of copolymers of styrene and of (meth)acrylic acid or a (Ci-C₂o)alkyl ester thereof under the INCI name: Styrene/ Acrylates Copolymer,

(vi) polyorganosilsesquioxanes, more particularly polymethyl-silsesquioxanes,

(vii) mineral particles chosen more particularly from metal oxides, silicates, glass particles, silica, calcium carbonate, magnesium carbonate, magnesium hydrogen carbonate and hydroxyapatite,

(viii) polyethylene; polyethylene (meth)acrylate, polypropylene, polytetrafluoroethylene (Teflon®), polyurethanes; expanded hollow particles of vinylidene chloride and acrylonitrile polymer, and

(ix) mixtures thereof. Preferably, among the materials that can constitute the shell (or dispersed material) of the microparticles, mention may be made of:

(i) polyorganosilsesquioxanes, more particularly polymethylsilsesquioxanes, (ii) crosslinked or non-crosslinked poly(meth)acrylate polymers,

(iii) cationic polymers,

(iv) poly-P-alanine, polyurea,

(v) polyethylene; polytetrafluoroethylene (Teflon®), polyurethanes; expanded hollow particles of vinylidene chloride and acrylonitrile polymer,

(vi) silica, for example fumed silicas,

(vii) hydroxyapatites (calcium phosphate hydroxide),

(viii) coated or uncoated metal oxide particles, and

(ix) mixtures thereof. Different variants of microparticles are detailed below, which do not limit the scope of the present invention.

First variant

According to the first variant of the invention, the solid microparticles in accordance with the invention may comprise a core comprising at least one polyorganosilsesquioxane.

According to a particular embodiment of this first variant, the microparticles are in the form of microspheres.

In the context of the present invention, a polyorganosilsesquioxane is more particularly a resin which is composed of trifunctional organosiloxane units represented by the following formula

in which R² is a substituted or unsubstituted monovalent hydrocarbon-based group containing 1 to 20 carbon atoms, illustrated by alkyl groups such as methyl, ethyl, propyl and butyl, aryl groups such as phenyl and tolyl groups, alkenyl groups such as vinyl and allyl, and aralkyl groups such as 2-phenylethyl and 2-phenylpropyl groups, and also substituted hydrocarbon-based groups obtained by replacing some or all of the hydrogen atoms in the hydrocarbon-based groups mentioned above with substituents, for example halogen atoms, epoxy groups, an amino group, a mercapto group and (meth)acryloxy, such as chloromethyl and 3,3,3-trifluoropropyl groups.

Advantageously, at least 50 mol% of the groups denoted by R² in the polyorganosilsesquioxane are methyl groups; more particularly at least 60%, especially at least 80%, for example at least 90%. According to an even more particular embodiment, the microparticles comprise a core comprising or even formed from polymethylsilsesquioxane.

In the context of this first variant of the invention, the microparticles bear a coating or shell on the core comprising at least one cationic polymer.

Preferably, the cationic polymer comprises units derived from (meth)acrylamide or from (meth)acrylic acid and cyclic units derived from dialkyldiallylammonium; the alkyl group, which is optionally hydroxylated, more particularly comprising from 1 to 6 carbon atoms. Even more particularly, the cationic polymer comprises units derived from (meth)acrylamide and cyclic units derived from dialkyldiallylammonium; the alkyl group, which is optionally hydroxylated, more particularly comprising from 1 to 6 carbon atoms.

Among the cationic polymers, mention may be made most particularly of Polyquaternium-6, Polyquaternium-7, Polyquaternium-22 and Polyquaternium-94, or mixtures thereof.

Said coating may also comprise at least one compound chosen from esters of a saturated or unsaturated C6-C24 fatty acid and of glycerol, the compound preferably being polyoxyalkylenated, and also silicone derivatives thereof. More particularly, mention may be made of PEG-7 glyceryl cocoate and the methylsilanol derivative Tri-PEG-8 glyceryl cocoate.

The particles according to this first variant may have a mean diameter of between 0.5 μιη and 20 μιη, preferably between 1 μιη and 10 μιη and preferably between 2 μιη and 7 μιη.

As examples of representative microparticles of this first variant of the invention, mention may be made especially of the microspheres Tospearl AQ® as sold by the company Momentive, designated by the following INCI name: polymethylsilsesquioxane (and) Polyquaternium-7 (and) PEG-7 Glyceryl Cocoate (and) Methylsilanol Tri-PEG-8 Glyceryl Cocoate.

Second variant

According to a second variant of the invention, the solid microparticles in accordance with the invention may be multilayer spherical composite particles.

More particularly, in the context of this second variant, the solid microparticles may comprise:

i) a core comprising at least one material A with a refractive index ranging from 1.3 to 1.8;

ii) at least one layer covering said core, comprising at least one material B with a refractive index ranging from 1.9 to 3.1 ;

iii) preferably, at least a second layer covering the material B, comprising at least one material C with a refractive index ranging from 1.3 to 1.8.

The term "refractive index", often denoted n, means the dimensionless magnitude characteristic of a material, describing the behaviour of light in said material.

The refractive index n, of a transparent medium, is defined by the ratio between the speed of propagation of light in a vacuum, c and its speed in this medium vi . In practice, the refractive index of a substance is measured relative to air. The refractive index n depends on the wavelength λ of the incident light, and on the temperature at which the measurement is carried out. In an absorbent medium, the refractive index is a complex number, the imaginary part of which gives an account of the attenuation of the wave.

The refractive index in particular intervenes in the Snell-Descartes laws, which involve the ratio of the refractive indices.

Take a light ray passing through a surface separating two transparent media of respective indices (ni) and (n₂). Take the angle i between the normal to the surface and the incident ray. The angle r of the refracted ray is obtained by:

ni x Sin( i ) = n₂ χ Sin( r )

The refractive indices according to the invention are measured at room temperature (20-25°C) by means of a refractometer, most of the models of which take a measurement of the limiting angle of refraction. This method is described in "Cours de Physique Generale Optique" ["Course in General Optical Physics"] by G. Bruhat (pages 12 to 14, sixth edition, published by Masson). The various layers of the spherical composite particles according to the invention are generally concentric.

The spherical composite particles in accordance with the invention are preferably characterized by a mean diameter of less than 50 μιη, more particularly between 0.5 and 20 μιη, and preferably less than or equal to 10 μιη.

The materials A, B and C may consist of organic and/or mineral substances.

Preferably, the mineral materials A and C with a refractive index of 1.3-1.8 may be chosen from the group formed by silica, calcium carbonate and aluminium oxide, and mixtures thereof.

Silica will more particularly be used for the materials A and C.

The mineral material B with a refractive index of 1.9-3.1 may be chosen from metal oxides, most particularly with zirconium and titanium oxides.

Preferentially, the layer based on the material B represents from 1% to 50% by weight and more preferentially from 5% to 30% by weight relative to the total weight of the spherical composite particle.

Preferentially, the layer based on the material C represents from 1% to 30% by weight and more preferentially from 2% to 10% by weight relative to the total weight of the spherical composite particle.

Composite particles in accordance with the invention are known per se. Their definitions and their preparation methods are described in patent JP 3605118.

Third variant

According to a third variant of the invention, the solid microparticles in accordance with the invention may be composite particles comprising a matrix that may comprise one or more organic and/or mineral materials and an additional mineral material different from the organic and/or mineral materials included in the matrix. The additional mineral material is generally chosen from metal oxides. According to a preferred embodiment, the matrix is essentially formed from an organic and/or mineral material.

The mineral materials that may be used in the matrix according to the third variant of the present invention are chosen from the group formed by mica, synthetic mica, talc, sericite, boron nitride, glass, calcium carbonate, barium sulfate, hydroxyapatite, silica, silicate, magnesium sulfate, magnesium carbonate, magnesium trisilicate, aluminium oxide, aluminium silicate, calcium silicate, calcium phosphate, magnesium oxide, bismuth oxychloride, kaolin, hydrotalcite, mineral clays and synthetic clays and mixtures thereof.

The organic materials that may be used to form the matrix are chosen from the group formed by poly(meth)acrylates, polyamides, silicones, polyurethanes, polyethylenes, polypropylenes, polystyrenes, polyhydroxyalkanoates, polycaprolactams, poly(butylene succinate)s, polysaccharides, polypeptides, polyvinyl alcohols, polyvinyl resins, fluoropolymers, polyesters and polyethers, and mixtures thereof. The additional mineral materials that may be used in the composite particle may be chosen from metal oxides.

Preferably, these metal oxides are chosen from titanium dioxide Ti0₂, zinc oxide ZnO and iron oxide FeO.

These metal oxides are in the form of particles with a mean size generally less than 200 run.

These metal oxides may also be in the form of layers, preferably multilayers with a mean thickness generally less than 200 nm.

Particularly preferably, the additional mineral material is Ti0₂.

Advantageously, the Ti0₂ particles used have a mean size of less than or equal to lOO nm.

The composite particles that may be used according to the invention are preferably spherical.

The mean size of the composite particles, which are advantageously spherical, is more particularly between 0.15 μιη and 30 μιη, preferably between 0.2 μιη and 20 μιη, more preferably between 0.3 μιη and 10 μιη, advantageously between 0.5 μιη and 10 μιη, for example between 1 and 10 μιη. The composite particles according to this third variant of the invention may be in various forms.

According to a first particular embodiment, the composite particles contain a matrix comprising an organic and/or mineral material, in which are included particles of additional mineral material. The additional mineral material is then said to be dispersed in the matrix. Preferably, the composite particles are formed from a matrix comprising an organic and/or mineral material, in which are included particles of additional mineral material.

According to this embodiment, the matrix has inclusions and particles of additional mineral material are placed in the inclusions of the matrix.

Preferably, the composite particles are spherical and have inclusions in which are placed particles of additional mineral material.

As composite particles corresponding to this variant, mention may be made of the products Sunsil TIN 50 and Sunsil TIN 40 sold by the company Sunjin Chemical. These spherical composite particles with a mean size between 2 and 7 μιη are formed from T1O2 encapsulated in a silica matrix.

According to a second particular embodiment, the composite particles contain a matrix made of an organic and/or mineral material, covered with a layer of additional mineral material connected to the matrix by means of a binder.

According to this second embodiment, the matrix particles are preferably spherical.

According to this second embodiment, the mean thickness of the layer of additional mineral material is generally about ten nanometres. The mean thickness of the layer of additional mineral material is advantageously between 1 and 200 nm and preferably between 10 and 200 nm.

The matrix may also be formed from one or more organic or mineral materials. There may then be a continuous phase of materials, such as an alloy, i.e. a continuous phase in which the materials can no longer be separated, or a discontinuous phase of materials, for example formed from an organic or mineral material covered with a layer of another different organic or mineral material.

The weight ratio of the matrix to the additional mineral material (matrix: additional mineral material) is generally between 100: 1 and 100:500. According to a particular embodiment of the third variant according to the invention, in particular when the composite particles comprise a matrix covered with a layer of additional mineral material, the composite particles may furthermore be covered with an additional coating, in particular chosen from biodegradable or biocompatible materials, lipid materials, for instance surfactants or emulsifiers, polymers, and oxides.

Preferably, the additional mineral material used in the composite particle is Ti0₂ or a mixture of Ti0₂ and ZnO.

Preferably, the matrix of the composite particle contains, and preferably is formed from, a material or a mixture of materials chosen from:

- Si0₂,

- alumina,

- mica,

- an alumina/triethoxycaprylylsilane mixture,

- talc,

- a mica/cyclomethicone/dimethicone/isododecane/ethyleneA^A copolymer mixture,

- PMMA (polymethyl methacrylate),

- Nylon.

Among the composite particles that may be used according to the invention, mention may also be made of the following particles:

- spherical composite particles with a mean size between 4 and 8 μιη, containing T1O2 and S1O2, having the trade name Eospoly TR sold by the company Creations Couleurs,

- composite particles with a mean size between 10 and 30 μιη, containing T1O2 and a mica/cyclomethicone/dimethicone/isododecane/ethyleneA^A copolymer matrix, having the trade name Micapoly UV Cristal TR35 sold by the company Creations Couleurs,

- composite particles containing T1O2 and ZnO and a PMMA matrix, having the trade name Sun PMMA-T50 sold by the company Sunjin Chemical. Fourth variant

According to a fourth variant of the invention, the solid microparticles in accordance with the invention may denote silicone elastomer powder coated with a silicone resin. These microparticles may be of spherical or amorphous form, and preferably of spherical form.

They will be referred to without distinction as "silicone elastomer" and "elastomeric organopolysiloxane".

The elastomeric organopolysiloxane is crosslinked and may be obtained via a crosslinking addition reaction of diorganopolysiloxane containing at least one hydrogen bonded to silicon and of diorganopolysiloxane containing ethylenically unsaturated groups bonded to silicon, especially in the presence of a platinum catalyst; or via a dehydrogenation crosslinking condensation reaction between a diorganopolysiloxane containing hydroxyl end groups and a diorganopolysiloxane containing at least one hydrogen bonded to silicon, especially in the presence of an organotin; or via a crosslinking condensation reaction of a diorganopolysiloxane containing hydroxyl end groups and of a hydrolysable organopolysilane; or via thermal crosslinking of organopolysiloxane, especially in the presence of an organoperoxide catalyst; or via crosslinking of organopolysiloxane by high-energy radiation such as gamma rays, ultraviolet rays or an electron beam.

Preferably, the crosslinked organopolysiloxane elastomer is obtained by a crosslinking addition reaction (A2) of a diorganopolysiloxane containing at least two hydrogens each bonded to a silicon, and (B2) of a diorganopolysiloxane containing at least two ethylenically unsaturated groups bonded to silicon, especially in the presence (C2) of a platinum catalyst, for instance as described in patent application EP-A-295 886.

In particular, the organopolysiloxane may be obtained by reaction of dimethylpolysiloxane bearing dimethylvinylsiloxy end groups and of methylhydrogenopolysiloxane bearing trimethylsiloxy end groups, in the presence of a platinum catalyst.

Compound (A2) is the base reagent for the formation of elastomeric organopolysiloxane and the crosslinking is performed by an addition reaction of compound (A2) with compound (B2) in the presence of the catalyst (C2). Compound (A2) is advantageously a diorganopolysiloxane containing at least two lower (for example of C2-C4) alkenyl groups; the lower alkenyl group may be chosen from vinyl, allyl and propenyl groups. These lower alkenyl groups may be located at any position on the organopolysiloxane molecule but are preferably located at the ends of the organopolysiloxane molecule. The organopolysiloxane (A2) may have a branched chain, linear chain, cyclic or network structure, but the linear chain structure is preferred. Compound (A2) may have a viscosity ranging from the liquid state to the gum state. Preferably, compound (A2) has a viscosity of at least 100 centistokes at 25°C.

The organopolysiloxanes (A2) may be chosen from methylvinylsiloxanes, methylvinylsiloxane-dimethylsiloxane copolymers, dimethylpolysiloxanes bearing dimethylvinylsiloxy end groups, dimethylsiloxane-methylphenylsiloxane copolymers bearing dimethylvinylsiloxy end groups, dimethylsiloxane-diphenylsiloxane- methylvinylsiloxane copolymers bearing dimethylvinylsiloxy end groups, dimethylsiloxane-methylvinylsiloxane copolymers bearing trimethylsiloxy end groups, dimethylsiloxane-methylphenylsiloxane-methylvinylsiloxane copolymers bearing trimethylsiloxy end groups, methyl(3,3,3-trifluoropropyl)polysiloxanes bearing dimethylvinylsiloxy end groups, and dimethylsiloxane-methyl(3,3,3- trifluoropropyl)siloxane copolymers bearing dimethylvinylsiloxy end groups.

Compound (B2) is in particular an organopolysiloxane containing at least two hydrogens bonded to silicon in each molecule and is thus the crosslinking agent for compound (A2).

Advantageously, the sum of the number of ethylenic groups per molecule in compound (A2) and the number of hydrogen atoms bonded to silicon per molecule in compound (B2) is at least 4.

Compound (B2) may be in any molecular structure, especially in a linear chain, branched chain or cyclic structure.

Compound (B2) may have a viscosity at 25°C ranging from 1 to 50 000 centistokes, especially so as to be miscible with compound (A).

It is advantageous for compound (B2) to be added in an amount such that the molecular ratio between the total amount of hydrogen atoms bonded to silicon in compound (B2) and the total amount of all the ethylenically unsaturated groups in compound (A2) is in the range from 1/1 to 20/1. Compound (B2) may be chosen from trimethylsiloxy-terminated methylhydrogenopolysiloxanes, trimethylsiloxy-terminated dimethylsiloxane/methylhydrosiloxane copolymers and dimethylsiloxane/methylhydrosiloxane cyclic copolymers.

Compound (C2) is the catalyst for the crosslinking reaction, and is especially chloroplatinic acid, chloroplatinic acid-olefm complexes, chloroplatinic acid- alkenylsiloxane complexes, chloroplatinic acid-diketone complexes, platinum black and platinum on a support.

The catalyst (C2) is preferably added in an amount of from 0.1 to 1000 parts by weight and better still from 1 to 100 parts by weight, as clean platinum metal, per 1000 parts by weight of the total amount of compounds (A2) and (B2).

Other organic groups may be bonded to silicon in the organopolysiloxanes (A2) and (B2) described previously, for instance alkyl groups such as methyl, ethyl, propyl, butyl or octyl; substituted alkyl groups such as 2-phenylethyl, 2-phenylpropyl or 3,3,3-trifluoropropyl; aryl groups such as phenyl, tolyl or xylyl; substituted aryl groups such as phenylethyl; and substituted monovalent hydrocarbon-based groups such as an epoxy group, a carboxylate ester group or a mercapto group.

Advantageously, the elastomeric organopolysiloxane powder is non- emulsifying.

The term "non-emulsifying" defines organopolysiloxane elastomers that do not contain a hydrophilic chain, such as polyoxyalkylene or polyglycerol units.

Spherical elastomeric organopolysiloxanes are especially described in patent applications JP-A-61-194 009, EP-A-242 219, EP-A-285 886 and EP-A-765 656. The elastomeric organopolysiloxane powder is coated with silicone resin.

According to a preferred embodiment, the silicone resin may be a silsesquioxane resin, as described, for example, in patent US 5 538 793.

Such elastomer powders coated with silicone resin are sold especially under the names KSP-lOO, KSP-101, KSP-102, KSP-103, KSP-104 and KSP-105 by the company Shin-Etsu.

Such powders correspond to the INCI name dimethicone silsesquioxane crosspolymer and in particular vinyl dimethicone/methicone silsesquioxane crosspolymer. According to another particular embodiment, the elastomeric organopolysiloxanes in the form of spherical powders may be powders of a hybrid silicone functionalized with fluoroalkyl groups, sold especially under the name KSP-200 by the company Shin-Etsu; powders of a hybrid silicone functionalized with phenyl groups, sold especially under the name KSP-300 by the company Shin-Etsu.

The elastomeric organopolysiloxane particles may have a JIS-A hardness of less than or equal to 80 (especially ranging from 5 to 80) and preferably less than or equal to 65 (especially ranging from 5 to 65). The JIS-A hardness is measured according to the method JIS K 6301 (1995) established by the Japanese Industrial Standards Committee.

In particular, the elastomeric organopolysiloxane particles may have a mean size ranging from 0.5 to 20 μιη, for example from 1 to 10 μιη and especially from 2 to 7 μιη.

Fifth variant

According to a fifth variant, the particles according to the invention may also be chosen from composite materials comprising microspheres of a first material, a plurality of particles of a second material, different from the first, which may be organic or mineral, and covering the first, and a residue of coupling agent that is reactive with the first and second materials; such that the particles of the second material are covalently linked to said microspheres.

More particularly, the first material is chosen from polymers of the type such as polyethylene, methyl methacrylate, Nylon, an ethylene (meth)acrylate copolymer, polyurethane and polyvinylidene copolymers.

The second material, which is more particularly mineral, is preferably chosen from pigments, talc, silica, sericites and titanium mica.

The coupling agent is chosen from aluminates, titanates and zirconates, and also from organo functional silanes. Preferably, the coupling agent is chosen from titanates, such as mono(Ci-C2o)alkoxy isostearyl titanate.

These particles are especially described in patent US 5 356 617. As particles that are suitable for use, mention may be made of the particles

SPCAT-12 (INCI name: talc/ethylene/methacrylate copolymer: isopropyl titanium triisostearate) sold by the company Kobo; but also SPCM-12 (INCI name: mica/ethylene/methacrylate copolymer: isopropyl titanium triisostearate) and DSMCS-12 (silica/ / ethylene/methacrylate copolymer: isopropyl titanium triisostearate), also sold by the company Kobo.

The particles, which are preferably spherical, preferably have a mean size of between 0.2 and 50 μιη and more particularly between 0.4 and 30 μιη.

Sixth variant

According to a sixth variant, the composite articles in accordance with the invention comprise a core comprising at least organic or mineral particles A; said core being covered at the surface, continuously or discontinuously, with an envelope (or shell) comprising at least organic or mineral particles B; A and B being different.

As regards the materials constituting the core of the particles, mention may be made most particularly of: (i) crosslinked or non-crosslinked poly(meth)acrylate and polyalkyl

(meth)acrylate polymers, especially polymethyl methacrylates, for instance the products sold under the trade names MR-7GC® by the company Soken, and the products SSX- 101® and SSX-102® sold by the company Sekisui Plastics;

(ii) crosslinked organopolysiloxane elastomers such as those described previously.

In particular, the silicone elastomer used in the present invention is chosen from Dimethicone Crosspolymer (INCI name), Vinyl Dimethicone Crosspolymer (INCI name), Dimethicone /Vinyl Dimethicone Crosspolymer (INCI name), Dimethicone Crosspolymer-3 (INCI name).

Mention may be made especially of the powders sold under the names Dow Corning 9505 Powder and Dow Corning 9506 Powder by the company Dow Corning, these powders having the INCI name: Dimethicone/vinyl dimethicone crosspolymer.

The organopolysiloxane powder may also be coated with silsesquioxane resin, as described, for example, in patent US 5 538 793. Such elastomeric powders are sold under the names KSP-lOO, KSP-101, KSP-102, KSP-103, KSP-104 and KSP-105 by the company Shin-Etsu, and have the INCI name: vinyl dimethicone/methicone silsesquioxane crosspolymer. As examples of organopolysiloxane powders coated with silsesquioxane resin that may advantageously be used according to the invention, mention may especially be made of the organopolysiloxane elastomers having the INCI name Vinyl Dimethicone/Methicone Silsesquioxane Crosspolymer, such as those sold under the commercial reference KSP-100 from the company Shin-Etsu.

(iii) polysaccharides, in particular natural polysaccharides or polysaccharides of natural origin. Among the polysaccharides that may be used according to the invention, mention may be made of native or modified starches.

Native starches

The starches that may be used in the present invention are more particularly macro molecules in the form of polymers formed from elementary moieties which are anhydroglucose units (dextrose), linked via a(l,4) bonds of chemical formula (C₆Hio05)n. The number of these moieties and their assembly make it possible to distinguish amylose, a molecule formed from about 600 to 1000 linearly linked glucose molecules, and amylopectin, a polymer branched approximately every 25 glucose residues (a(l,6) bond). The total chain may include between 10 000 and 100 000 glucose residues. Starch is described in particular in the Kirk-Othmer Encyclopaedia of Chemical Technology, 3rd edition, volume 21, pages 492-507, Wiley Interscience, 1983. The relative proportions of amylose and amylopectin and their degree of polymerization vary as a function of the botanical origin of the starches. On average, a sample of native starch consists of about 25% amylose and 75% amylopectin. Occasionally, phytoglycogen is present (between 0%> and 20% of the starch), which is an analogue of amylopectin but branched every 10 to 15 glucose residues.

The botanical origin of the starch molecules used in the present invention may be cereals or tubers. Thus, the starches are chosen, for example, from corn starch, rice starch, tapioca starch, cassava starch, barley starch, potato starch, wheat starch, sorghum starch and pea starch. The native starches are represented, for example, by the products sold under the names C*AmilogelTM, Cargill GelTM, C* GelTM, Cargill GumTM, DryGelTM and C*Pharm GelTM by the company Cargill, under the name Corn Starch by the company Roquette, and under the name Tapioca Pure by the company National Starch.

Modified starches

The modified starches used in the composition of the invention may be modified via one or more of the following reactions: pregelatinization, degradation (acid hydrolysis, oxidation, dextrinization), substitution (esterification, etherification), crosslinking (esterification), bleaching. More particularly, these reactions can be carried out in the following way:

- pregelatinization by splitting the starch granules (for example drying and cooking in a drying drum);

- acid hydrolysis giving rise to very rapid retrogradation on cooling;

- oxidation with strong oxidizing agents (alkaline medium, in the presence of sodium hypochlorite NaOCl for example) leading to the depolymerization of the starch molecule and to the introduction of carboxyl groups into the starch molecule (mainly oxidation of the hydroxyl group at C6);

- dextrinization in acid medium at high temperature (hydrolysis followed by repolymerization);

- crosslinking with functional agents capable of reacting with the hydroxyl groups of the starch molecules, which will thus bond together (for example with glyceryl and/or phosphate groups);

- esterification in alkaline medium for the grafting of functional groups, in particular Ci-C₆ acyl (acetyl), Ci-C₆ hydroxyalkyl (hydroxyethyl or hydroxypropyl), carboxymethyl or octenylsuccinic.

Monostarch phosphates (of the type St-0-PO-(OX)₂), distarch phosphates (of the type St-O-PO-(OX)-O-St) or even tristarch phosphates (of the type St-0-PO-(0-St)₂) or mixtures thereof may especially be obtained by crosslinking with phosphorus compounds.

X especially denotes alkali metals (for example sodium or potassium), alkaline-earth metals (for example calcium or magnesium), ammonium salts, amine salts, for instance those of monoethanolamine, diethanolamine, triethanolamine, 3-amino-l,2- propanediol, or ammonium salts derived from basic amino acids such as lysine, arginine, sarcosine, ornithine or citrulline.

The phosphorus compounds can, for example, be sodium tripolyphosphate, sodium orthophosphate, phosphorus oxychloride or sodium trimetaphosphate.

The starch molecules may be derived from any plant source of starch, especially such as corn, potato, oat, rice, tapioca, sorghum, barley or wheat. It is also possible to use the starch hydrolysates mentioned above.

The modified starches are represented, for example, by the products sold under the names C*Tex-Instant (pregelatinized adipate), C*StabiT ex-Instant (pregelatinized phosphate), C*PolarT ex-Instant (pregelatinized hydroxypropyl), C*Set (acid hydrolysis, oxidation), C*size (oxidation), C*BatterCrisp (oxidation), C*DrySet (dextrinization), C*TexTM (acetyl distarch adipate), C*PolarTexTM (hydroxypropyl distarch phosphate), C* StabiTexTM (distarch phosphate, acetyl distarch phosphate) by the company Cargill, by distarch phosphates or compounds rich in distarch phosphate such as the product sold under the references Prejel VA-70-T AGGL (gelatinized hydroxypropyl cassava distarch phosphate) or Prejel TK1 (gelatinized cassava distarch phosphate) or Prejel 200 (gelatinized acetyl cassava distarch phosphate) by the company Avebe or Structure Zea from National Starch (gelatinized corn distarch phosphate).

As examples of oxidized starches, use will be made especially of those sold under the name C*size from the company Cargill.

Celluloses and derivatives thereof may be used among the polysaccharides and, preferentially, said celluloses will be porous.

The porosity of celluloses may be determined by their specific surface area ranging from 0.05 m²/g to 1500 m²/g, more preferentially from 0.1 m²/g to 1000 m²/g and even more preferentially from 0.2 m²/g to 500 m²/g according to the BET method.

According to a particular form of the invention, cellulose may be of the I type or of the II type or any equivalent. Celluloses of II type will preferentially be used.

According to a particular form of the invention, the cellulose derivatives may be chosen from cellulose esters and cellulose ethers. The term "cellulose ester" means a polymer formed from a(l-4) sequences of partially or totally esterified anhydroglucose rings, the esterification being obtained by reaction of one or all of the free hydroxyl functions of said anhydroglucose rings with a linear or branched carboxylic acid or a carboxylic acid derivative (acid chloride or acid anhydride) containing from 1 to 4 carbon atoms.

Preferably, the cellulose esters result from the reaction of a few free hydroxyl functions of said rings with a carboxylic acid containing from 1 to 4 carbon atoms.

Advantageously, the cellulose esters are chosen from cellulose acetates, cellulose propionates, cellulose butyrates, cellulose isobutyrates, cellulose acetobutyrates and cellulose acetopropionates, and mixtures thereof.

These cellulose esters may have a weight-average molecular weight ranging from 3000 to 1 000 000, preferably from 10 000 to 500 000 and more preferentially from 15 000 to 300 000.

The term "cellulose ether" means a polymer formed from a(l-4) sequences of partially or totally etherified anhydroglucose rings, some of the hydroxyl functions of said rings being substituted with a radical -OR, in which R is preferably a linear or branched alkyl radical containing from 1 to 4 carbon atoms.

The cellulose ethers are preferably chosen from cellulose alkyl ethers with a

C1 -C4 alkyl group such as cellulose methyl ether, cellulose propyl ether, cellulose isopropyl ether, cellulose butyl ether and cellulose isobutyl ether.

These cellulose ethers may have a weight-average molecular weight ranging from 3000 to 1 000 000, preferably from 10 000 to 500 000 and more preferentially from 15 000 to 300 000.

As core particles chosen from spherical cellulose particles, mention may be made of the following commercial products sold by the company Daito Kasei in Japan:

- Cellulobeads USF® with a particle size of 4 μιη (porous cellulose),

- Cellulobeads D-5® with a particle size of 10 μιη,

- Cellulobeads D-10® with a particle size of 15 μιη,

- Moiscell PW D-5 XP® with a particle size of 10 μιη (potassium cellulose succinate), and - Moiscell PW D-50 XP® with a particle size of 50 μηι (potassium cellulose succinate).

The products Cellulobeads USF® and Cellulobeads D-5® are preferential, more particularly the product Cellulobeads USF®.

(iv) polyamide particles.

The polyamide particles used in the invention may be those sold under the name Orgasol by the company Atochem. The process for obtaining these particles is the one described, for example, in document FR 2 619 385 or in document EP 303 530. These polyamide particles are moreover known according to their various physicochemical properties under the name polyamide 12 (INCI name: Nylon- 12) or polyamide 6 (INCI name: Nylon-6). The particles used in the invention may also be those sold under the name SP500® by the company Kobo.

(v) particles of copolymer of styrene and of (meth)acrylic acid or a (Ci- C₂o)alkyl ester thereof under the INCI name: Styrene/acrylates copolymer, for instance the product sold under the trade name Sunspheres Powder® by the company Rohm & Haas, such as those described in patent US 5 663 213 and patent application EP 1 092 421.

(vi) polymethylsilsesquioxanes which are obtained by hydrolysis and condensation of methyltrimethoxysilane such as the products sold under the trade names AEC Silicone Resin Spheres® (A & E Connock (Perfumery & Cosmetics) Ltd.), Belsil PMS MK® (Wacker Chemie AG), Granpowder BUI 9® (Grant Industries, Inc.), Gransil PSQ® (Grant Industries, Inc.), Gransil PSQ-W® (Grant Industries, Inc.), KMP-590® (Shin-Etsu Chemical Co.), KMP-599® (Shin-Etsu Chemical Co.), MSP-K050® (Nikko Rica Corporation), SilDerm SQ® (Active Concepts LLC), SilForm Flexible Resin® (Momentive Performance Materials), SilPearl 508® (Koda Corporation), Si-Tec PMS® (Ashland Inc.), Tospearl 2000® Tospearl 120A®, Tospearl 130A®, Tospearl 145A®, Tospearl 1 1 10A®, Tospearl 3000A®, Tospearl 2000B® and Tospearl 150KA® (Momentive Performance Materials). (vii) mineral particles, for instance:

- metal oxides such as zirconium oxides, cerium oxides, iron oxides and titanium oxides,

- alumina,

- silicates such as talc, clays and kaolin,

- glass particles,

- silica (silicon dioxide),

- calcium carbonate or magnesium carbonate,

- magnesium hydrogen carbonates,

- hydroxyapatite.

Among the silica particles, mention may be made of hollow spherical silica particles such as the products sold under the trade names Silica Beads SB 700® and Silica Beads SB 700 from the company Maprecos, and Sunspheres H-33® and Sunspheres H- 51® from the company Asahi Glass.

(vii) mixtures thereof. Among the materials constituting the envelope of the composite particles in accordance with the invention, mention may be made of:

(i) polymethylsilsesquioxanes such as those mentioned previously; (ii) crosslinked or non-crosslinked poly(meth)acrylate polymers such as those mentioned previously;

(iii) fumed silicas.

The fumed silicas may be hydrophilic or lipophilic. The hydrophilic fumed silicas are obtained by pyrolysis of silicon tetrachloride (SiC14) in a continuous flame at 1000°C in the presence of hydrogen and oxygen. Among the fumed silicas of hydrophilic nature that may be used according to the present invention, mention may especially be made of those sold by the company Degussa or Evonik Degussa under the trade names Aerosil® 90, 130, 150, 200, 300 and 380 or alternatively by the company Cabot under the name Carbosil H5.

The lipophilic fumed silicas may be hydrophobic-surface-treated fumed silicas. This is because it is possible to chemically modify the surface of the silica, by chemical reaction generating a reduction in the number of silanol groups present at the surface of the silica. It is especially possible to substitute silanol groups with hydrophobic groups: a hydrophobic silica is then obtained.

The hydrophobic groups may be:

- trimethylsiloxyl groups, which are obtained especially by treating fumed silica in the presence of hexamethyldisilazane. Silicas thus treated are named "silica silylate" according to the CTFA (8th edition, 2000). They are sold, for example, under the references Aerosil R812® by the company Degussa, and Cab-O-Sil TS-530® by the company Cabot;

- dimethylsilyloxyl or polydimethylsiloxane groups, which are obtained in particular by treating fumed silica in the presence of polydimethylsiloxane or dimethyldichlorosilane. Silicas thus treated are known as "silica dimethyl silylate" according to the CTFA (8th edition, 2000). They are sold, for example, under the references Aerosil R972® and Aerosil R974® by the company Degussa, and Cab-O-Sil TS-610® and Cab-O-Sil TS-720® by the company Cabot. (iv) hydroxyapatites (Calcium Phosphate Hydroxide) such as the commercial products sold under the names Apatite Powder AD-1® (Advance Company, Ltd.), Hydroxysomes® (Laboratory Skin Care (LSC), Inc.) and Pearl Apatite® (Mikimoto Pharmaceutical Co., Ltd.). (v) coated or uncoated metal oxide particles. They may be chosen especially from titanium oxide, zinc oxide, iron oxide, zirconium oxide and cerium oxide, or mixtures thereof. According to this variant of the invention, coated or uncoated titanium oxide particles are particularly preferred.

Such coated or uncoated metal oxide particles are described in particular in patent application EP-A-0 518 773. Commercial pigments that may be mentioned include the products sold by the companies Sachtleben Pigments, Tayca, Merck and Degussa.

The metal oxide particles may be coated or uncoated. They have a mean elementary particle size of less than or equal to 0.5 μιη, more preferentially between 0.005 and 0.5 μιη, even more preferentially between 0.01 and 0.2 μιη, better still between 0.01 and 0.1 μιη and more particularly between 0.015 and 0.05 μιη.

The coated particles are particles that have undergone one or more surface treatments of chemical, electronic, mechanochemical and/or mechanical nature with compounds such as amino acids, beeswax, fatty acids, fatty alcohols, anionic surfactants, lecithins, sodium, potassium, zinc, iron or aluminium salts of fatty acids, metal alkoxides (of titanium or aluminium), polyethylene, silicones, proteins (collagen, elastin), alkanolamines, silicon oxides, metal oxides or sodium hexametaphosphate.

The coated particles are more particularly titanium oxides that have been coated:

- with silica, such as the product Sunveil® from the company Ikeda, - with silica and iron oxide, such as the product Sunveil F® from the company

Ikeda,

- with silica and alumina, such as the products Microtitanium Dioxide MT 500 SA® and Microtitanium Dioxide MT 100 SA from the company Tayca and Tioveil from the company Tioxide,

- with alumina, such as the products Tipaque TTO-55 (B)® and Tipaque TTO-

55 (A)® from the company Ishihara and UVT 14/4 from the company Sachtleben Pigments,

- with alumina and aluminium stearate, such as the products Microtitanium Dioxide MT 100 T®, MT 100 TX®, MT 100 Z® and MT-01® from the company Tayca, the products Solaveil CT-10 W® and Solaveil CT 100® from the company Uniqema and the product Eusolex T-AVO® from the company Merck, - with silica, alumina and alginic acid, such as the product MT-100 AQ® from the company Tayca,

- with alumina and aluminium laurate, such as the product Microtitanium Dioxide MT 100 S® from the company Tayca,

- with iron oxide and iron stearate, such as the product Microtitanium Dioxide

MT 100 F® from the company Tayca,

- with zinc oxide and zinc stearate, such as the product BR 351® from the company Tayca,

- with silica and alumina and treated with a silicone, such as the products Microtitanium Dioxide MT 600 SAS®, Microtitanium Dioxide MT 500 SAS® or

Microtitanium Dioxide MT 100 SAS® from the company Tayca,

- with silica, alumina and aluminium stearate and treated with a silicone, such as the product STT-30-DS® from the company Titan Kogyo,

- with silica and treated with a silicone, such as the product UV-Titan X 195® from the company Sachtleben Pigments,

- with alumina and treated with a silicone, such as the products Tipaque TTO- 55 (S)® from the company Ishihara or UV Titan M 262® from the company Sachtleben Pigments,

- with triethanolamine, such as the product STT-65-S from the company Titan Kogyo,

- with stearic acid, such as the product Tipaque TTO-55 (C)® from the company Ishihara,

- with sodium hexametaphosphate, such as the product Microtitanium Dioxide MT 150 W® from the company Tayca,

- Ti02 treated with octyltrimethylsilane, sold under the trade name T 805® by the company Degussa Silices,

- Ti02 treated with a polydimethylsiloxane, sold under the trade name 70250 Cardre UF Ti02SI3® by the company Cardre,

- anatase/rutile Ti02 treated with a polydimethylhydrogenosiloxane, sold under the trade name Microtitanium Dioxide USP Grade Hydrophobic® by the company Color

Techniques. The uncoated titanium oxide particles are sold, for example, by the company Tayca under the trade names Microtitanium Dioxide MT 500 B or Microtitanium Dioxide MT 600 B®, by the company Degussa under the name P 25, by the company Wackherr under the name Transparent titanium oxide PW®, by the company Miyoshi Kasei under the name UFTR®, by the company Tomen under the name ITS® and by the company Tioxide under the name Tioveil AQ®.

(vi) mixtures thereof. Among the materials constituting the particles B, mention may also be made of poly-P-alanine powders, polyethylene powders; tetrafluoroethylene (Teflon®) powders, polyurea powders; polyurethane powders such as the copolymer of hexamethylene diisocyanate and of trimethylol sold under the name Plastic Powder D-400® by Toshiki; hollow expanded particles of vinylidene chloride and acrylonitrile polymer, such as the product sold under the name Expancel® by the company Expancel.

According to this particular variant of the invention, the composite particles are chosen from:

- composite particles whose core is formed from crosslinked polymethyl methacrylate and whose envelope is formed from hydroxyapatite, such as those sold under the name PAC-2® by the company Sekisui Plastics;

- composite particles whose core is formed from crosslinked polymethyl methacrylate and whose envelope is formed from fumed silica, such as the product sold under the trade name Micropearl M330® by the company Matsumoto Yushi;

- composite particles whose core is formed from organopolysiloxane elastomer and whose envelope is formed from fumed silica, such as the particles whose core is formed from dimethicone/vinyl dimethicone crosspolymer and whose envelope is formed from fumed silica, such as the product sold under the name DC 9701 Cosmetic Powder® by Dow Corning (INCI name: Dimethicone/vinyl dimethicone crosspolymer (and) silica);

- composite particles whose core is formed from crosslinked polymethyl methacrylate and whose envelope is formed from polymethylsilsesquioxane, such as the product sold under the name Silcrusta MK03® from Kobo (INCI name: Methyl Methacrylate Crosspolymer (and) Polymethylsilsesquioxane);

- composite particles whose core is formed from a polysaccharide, which is in particular natural or of natural origin, and whose envelope is formed from polymethyl methacrylate;

- composite particles whose core is formed from polymethyl methacrylate and whose envelope is formed from fumed silica;

- composite particles whose core is formed from polymethylsilsesquioxane and whose envelope is formed from fumed silica;

- composite particles whose core is formed from polymethyl methacrylate and whose envelope is formed from titanium oxide; in particular titanium oxide coated with silica, alumina and alginic acid, such as the product MT-100 AQ from the company Tayca.

According to a particular form of the invention, the composite particles in accordance with the invention are composite particles whose core is formed from a polysaccharide, which is in particular natural or of natural origin, and whose envelope is formed from polymethyl methacrylate.

Preparation processes

The composite particles in accordance with this variant of the invention may be manufactured according to the standard techniques for manufacturing core/shell composite particles.

According to a preferential manufacturing method, the composite particles in accordance with the invention will be synthesized according to a dry coating technique (without liquid medium), in particular according to the mechanochemical melting technique.

A mechanochemical melting process consists of a process in which mechanical power such as a compression force, a friction force or shear is exerted on a plurality of elements, bringing about the melting of said elements.

The mechanochemical melting process may be performed with a machine comprising a rotary chamber and an internal part attached to a scraper, such as the machine sold under the trade name Hosokawa Micron Corporation, Japan. A mechanochemical melting hybridizer process will preferably be used.

The hybridizer process was developed in the 1980s. The hybridizer process is a type of mechanochemical melting process in which strong mechanical power is applied to a plurality of particles in order to bring about a mechanochemical reaction so as to form composite particles.

According to the hybridizer process, the mechanical power is produced by a high-speed rotor which may have a diameter ranging from 10 cm to 1 m and which can rotate at a speed ranging from 1000 to 10 000 rpm. The hybridizer process may be performed in air or under a dry atmosphere. Specifically, high-speed rotation of the rotor can generate a flow of air at high speed in proximity to the rotor. Liquid materials may be subjected to the hybridizer process in the presence of solid materials.

The hybridizer process may be performed using a hybridization system sold under the trade name Nara Machinery, in which at least two types of particles, generally core particles and fine particles, are introduced into a hybridizer equipped with a high- speed rotor having a plurality of blades in a dry chamber, the particles are dispersed in the chamber and mechanical and thermal energy (compression, friction and shear) are exerted on the particles for a short period of time such as from 1 to 10 minutes and preferably from 1 to 5 minutes. As a result, particles of one type (fine particles) are integrated or fixed onto particles of another type (i.e. particles with a core) to form composite particles. It is preferable for the particles to be subjected to an electrostatic treatment, for example by shaking them to form an "ordered mixture" in which particles of one type are spread out to cover the other type of particles. The hybridizer process may be performed using a Theta composer sold by Tokuju Corporation.

The hybridizer process may be performed using a machine such as the Composi Hybrid or Mechano Hybrid machine sold by Nippon Coke.

The solid microparticles in accordance with the invention may be present at concentrations of less than 10% by weight relative to the total weight of the emulsion and preferably at concentrations ranging from 1% to 10% by weight relative to the total weight of the emulsion, in particular from 1% to 7% by weight. Preferably, the microparticles are chosen from compounds for which the materials that may form the core (or matrix) are chosen from:

(ii) crosslinked organopolysiloxane elastomers,

(iv) polyorganosilsesquioxanes, more particularly polymethyl-silsesquioxanes,

(v) mineral particles chosen more particularly from metal oxides, silicates, glass particles, silica, calcium carbonate, magnesium carbonate, magnesium hydrogen carbonate and hydroxyapatite, and

(vi) polyethylene; polyethylene (meth)acrylate, polypropylene, polytetrafluoroethylene (Teflon®), polyurethanes; expanded hollow particles of vinylidene chloride and acrylonitrile polymer, and

(vii) mixtures thereof

(viii) mixtures thereof.

Preferably, among the materials that can constitute the shell (or dispersed material) of the microparticles, mention may be made of:

(i) polyorganosilsesquioxanes, more particularly polymethylsilsesquioxanes,

(ii) crosslinked or non-crosslinked poly(meth)acrylate polymers,

(iii) cationic polymers,

(iv) silica, for example fumed silicas,

(v) coated or uncoated metal oxide particles, and

(vi) mixtures thereof.

According to a particular embodiment of the invention, the microparticles are chosen from:

(1) microspheres comprising a core comprising at least one polyorganosiloxane, especially a polymethylsilsesquioxane, said core being covered with a cationic polymer, especially a Polyquaternium, (2) multilayer composite spherical particles comprising:

ii) at least one layer covering said core, comprising at least one material B with a refractive index ranging from 1.9 to 3.1;

iii) preferably, at least a second layer covering the material B, comprising at least one material C with a refractive index ranging from 1.3 to 1.8,

(3) composite particles comprising a matrix that may comprise one or more organic and/or mineral materials and an additional mineral material different from the organic and/or mineral materials included in the matrix,

(4) powder of spherical or amorphous form, and preferably of spherical form, of elastomer coated with silicone resin,

(5) talc, mica or silica particles covered with at least one ethylene/methacrylate copolymer,

(6) composite particles whose core is formed from a polysaccharide, which is in particular natural or of natural origin, and whose envelope is formed from polymethyl methacrylate, and

(7) composite particles whose core is formed from crosslinked polymethyl methacrylate and whose envelope is formed from polymethylsilsesquioxane.

OILS

The emulsion according to the invention comprises two oily phases, a first oily phase comprising at least a first oil chosen from silicone oils, hydrocarbon-based oils and fluoro oils, and a second oily phase comprising at least a second oil that is immiscible with the first oil(s), at room temperature and at atmospheric pressure (760 mmHg/1.013^x 10⁵ Pa). For the purposes of the present invention, the term "immiscible oils" means that the mixing of these two oils does not lead to a homogeneous one-phase solution. Said mixing is performed with the same weight amount of each oil.

For the purposes of the invention, the term "oil" means a compound whose maximum viscosity is 200 000 cPs (200 Pa.s) at 25°C.

Also, and preferably, at least one of the oils is chosen from water-immiscible compounds (mixing performed with the same weight amount of water). In accordance with a particularly advantageous embodiment of the invention, the oil(s) are chosen from water- immiscible compounds.

It should be noted that the viscosities are measured according to the following protocol:

The viscosity is measured at 25°C ± 0.5°C using a Haake RS600 controlled- stress rheometer from the company Thermo Rheo equipped with a spindle of cone/plate geometry with a diameter of between 2 cm and 6 cm and an angle of between 1° and 2°, the choice of the spindle depending on the viscosity to be measured (the more fluid the formulation, the greater the diameter of the chosen cone and the smaller the angle).

The measurement is performed by applying on the oil sample a logarithmic ramp of shear gradient ε' ranging from 10^"3 s^"1 to 1000 s^"1 for a duration of 5 minutes.

The rheogram representing the change in viscosity as a function of the shear gradient ε' is then plotted.

The value under consideration is that of the viscosity at 500 s^"1, whether it is measured at this gradient or extrapolated by the plot if no experimental point corresponds to this value.

More particularly, the oils are said to be "immiscible" when mixing them leads to a separation of phases according to the following protocols:

For oils whose viscosity is less than 10 000 cPs (10 Pa.s) at 25°C, the two oils to be evaluated are introduced (5 g/5 g) at room temperature into a conical-tipped plastic centrifuge tube (ref. Corning® 15mL PET Centrifuge Tubes, Rack Packed with Plug Seal Cap, Sterile (Product #430055), which is placed in a Vortex Genie 2 machine. Stirring is performed at speed 10 for 10 seconds, followed by manual inversion of the tube before replacing it in the Vortex machine. This cycle is repeated three times in succession. The mixture is then left to stand at room temperature for 48 hours. If at least one of the oils has a viscosity of greater than or equal to 10 000 cPs (10 Pa.s) at 25°C, then the mixture of the two oils (5 g/5 g) is placed in an oven at 50°C for 30 minutes before performing the three stirring cycles described previously.

The mixture is then observed.

When the mixture is separated into two phases and the separation of the two phases is sharply delimited at the interface, the phases are said to be "separated" and the oils are consequently immiscible.

In the contrary case, the mixture is observed using a phase-contrast microscope, at room temperature (about 25°C). If a continuous phase and a dispersed phase in the form of drops are observed, the phases are said to be "separated" and the oils are considered as immiscible.

If the observation of the mixture reveals only a single phase, then the phases are said to be "non-separated" and the oils are considered as miscible.

This same protocol is used to check the miscibility of the oil with water.

More particularly, the O/O emulsion according to the invention comprises at least a first oily phase containing at least one non-volatile oil, and a second oily phase containing at least one volatile or non- volatile oil.

Preferably, the first and second oily phases each contain at least one nonvolatile oil.

The term "non- volatile" refers to an oil whose vapour pressure at room temperature (25°C) and atmospheric pressure is non-zero and is less than 10^"3 mmHg (0.13 Pa).

The term "volatile" refers to an oil that can evaporate on contact with the skin in less than one hour, at room temperature and atmospheric pressure.

More particularly, the term "volatile oil" means an oil which has a non-zero vapour pressure, at room temperature (25°C) and atmospheric pressure, in particular having a vapour pressure ranging from 0.13 Pa to 40 000 Pa, preferably ranging from 1.3 Pa to 13 000 Pa and preferentially ranging from 1.3 Pa to 1300 Pa.

A preferred embodiment of the invention concerns an oil/oil emulsion in which said first non-volatile oil or second oil, preferably said first oil, is chosen from silicone oils and fluoro oils, or mixtures thereof, and more particularly from non-volatile non-phenyl silicone oils; non-volatile phenyl silicone oils, optionally bearing at least one dimethicone fragment; fluoro oils; or mixtures thereof.

Another preferred embodiment of the invention relates to an oil/oil emulsion in which the first or the second non-volatile oil, preferably the second oil, is chosen from polar hydrocarbon-based non-volatile oils, in particular chosen from non-volatile oils comprising at least one free hydroxyl group or not comprising any, or from non- volatile oils comprising at least two free hydroxyl groups, or from non- volatile hydrocarbon-based apolar oils, or mixtures thereof. First oily phase

The first oily phase comprises at least a first non-volatile oil chosen from silicone oils, fluoro oils and hydrocarbon-based oils, or mixtures thereof, and more particularly, in accordance with a first embodiment, from non-phenyl non- volatile silicone oils; phenyl non-volatile silicone oils, optionally bearing at least one dimethicone fragment; fluoro oils; or mixtures thereof.

In accordance with a second embodiment, the first oily phase comprises at least a first hydrocarbon-based oil.

This first oily phase may be the continuous phase or the dispersed phase.

The term "silicone oil" means an oil containing at least one silicon atom, and in particular containing Si-0 groups.

The term "polar hydrocarbon-based oil" means an oil formed essentially from, or even constituted by, carbon and hydrogen atoms, and also heteroatoms such as oxygen and nitrogen atoms, and not containing any silicon or fluorine atoms.

The term "fluoro oil" means an oil containing at least one fluorine atom.

1. Silicone oils

Non-volatile non-phenyl silicone oils

The term "non-phenylated silicone oil" or "non-phenyl silicone oil" denotes a silicone oil which does not bear any phenyl substituents.

Representative examples of these non-volatile non-phenyl silicone oils which may be mentioned include polydimethylsiloxanes; alkyl dimethicones; vinylmethyl methicones; and also silicones modified with aliphatic groups and/or with functional groups such as hydroxyl, thiol and/or amine groups.

It should be noted that "dimethicone" (INCI name) corresponds to a polydimethylsiloxane (chemical name).

In particular, these oils may be chosen from the following non- volatile non- phenyl silicone oils:

- polydimethylsiloxanes (PDMSs),

- PDMSs comprising aliphatic groups, in particular alkyl or alkoxy groups, which are pendent and/or at the end of the silicone chain, these groups each comprising from 2 to 24 carbon atoms,

- PDMSs comprising at least one aliphatic group and/or at least one functional group such as hydroxyl, thiol and/or amine groups,

- polysiloxanes modified with fatty acids, fatty alcohols or polyoxyalkylenes, and mixtures thereof.

The non- volatile non-phenyl silicone oil is preferably chosen from non- volatile dimethicone oils.

Preferably, these non-volatile non-phenylated silicone oils are chosen from polydimethylsiloxanes; alkyl dimethicones and also PDMSs comprising at least one aliphatic group, in particular C2-C24 alkyl groups and/or at least one functional group such as hydroxyl, thiol and/or amine groups.

The non-phenyl silicone oil may be chosen in particular from silicones of formula (Γ):

(Γ)

in which:

Pvi , P 2, P 5 and Re are, together or separately, an alkyl radical containing from 1 to 6 carbon atoms, R₃ and R₄ are, together or separately, an alkyl radical containing from 1 to 6 carbon atoms, a vinyl radical, an amine radical or a hydroxyl radical,

X is an alkyl radical containing from 1 to 6 carbon atoms, a hydroxyl radical or an amine radical,

n and p are integers chosen so as to have a fluid compound, in particular whose viscosity at 25°C is between 9 centistokes (cSt) (9 x 10^"6 m²/s) and 800 000 cSt (i.e. between 8 mPa.s and 720 000 mPa.s).

As non-volatile non-phenyl silicone oils that may be used according to the invention, mention may be made of those for which:

- the substituents Ri to 5 and X represent a methyl group, and p and n are such that the viscosity is 500 000 cSt (i.e. 450 000 mPa.s), for example the product sold under the name SE30 by the company General Electric, the product sold under the name AK 500000 by the company Wacker, the product sold under the name Mirasil DM 500 000 by the company Bluestar, and the product sold under the name Dow Corning 200 Fluid 500 000 cSt (i.e. 450 000 mPa.s) by the company Dow Corning,

- the substituents Ri to 5 and X represent a methyl group, and p and n are such that the viscosity is 60 000 cSt (54 000 mPa.s), for example the product sold under the name Dow Corning 200 Fluid 60 000 CS by the company Dow Corning, and the product sold under the name Wacker Belsil DM 60 000 by the company Wacker,

- the substituents Ri to 5 and X represent a methyl group, and p and n are such that the viscosity is 100 cSt (i.e. 90 mPa.s) or 350 cSt (i.e. 315 mPa.s), for instance the products sold by the company Dow Corning under the name Dow Corning® 200 Fluid 100 cSt or Dow Corning® SH 200 Fluid 100 CS; or alternatively sold by the company Wacker under the name Belsil DM100 dimethicone,

- the substituents Ri to 5 represent a methyl group, the group X represents a hydroxyl group, and n and p are such that the viscosity is 700 cSt (630 mPa.s), for example the product sold under the name Baysilone Fluid TO.7 by the company Momentive. Non-volatile phenyl silicone oils

The expression "phenylated silicone oil" or "phenyl silicone oil" denotes a silicone oil bearing at least one phenyl substituent.

These phenyl silicone oils may be chosen from those which also bear at least one dimethicone fragment, or from those which do not bear any.

According to the invention, a dimethicone fragment corresponds to the following unit:

-Si(CH3)₂-0-, this fragment not being located at one end. The non- volatile phenyl silicone oil may thus be chosen from:

a) phenyl silicone oils optionally bearing a dimethicone fragment corresponding to formula (I) below:

R

I R R

R— Si O I

I I Si- -O Si-

R R

I R

R— Si O

I

R (I)

in which the groups R, which are monovalent or divalent, represent, independently of each other, a methyl or a phenyl, with the proviso that at least one group R represents a phenyl.

Preferably, in this formula, the phenyl silicone oil comprises at least three, for example at least four, at least five or at least six, phenyl groups. b) phenyl silicone oils optionally bearing a dimethicone fragment corresponding to formula (II) below:

R R R

I I I

R Si O Si O Si R

I I I

R R R (II)

in which the groups R represent, independently of each other, a methyl or a phenyl, with the proviso that at least one group R represents a phenyl.

Preferably, in this formula, the compound of formula (II) comprises at least three, for example at least four or at least five, phenyl groups. Mixtures of different phenylorganopolysiloxane compounds described above can be used.

Examples that may be mentioned include mixtures of triphenyl-, tetraphenyl- or pentaphenyl-organopolysiloxanes.

Among the compounds of formula (II), mention may more particularly be made of phenyl silicone oils which do not bear a dimethicone fragment, corresponding to formula (II) in which at least 4 or at least 5 radicals R represent a phenyl radical, the remaining radicals representing methyls.

Such non- volatile phenyl silicone oils are preferably trimethylpentaphenyltrisiloxane or tetramethyltetraphenyltrisiloxane. They are in particular sold by Dow Corning under the reference PH-1555 HRI or Dow Corning 555 Cosmetic Fluid (chemical name: l,3,5-trimethyl-l,l,3,5,5-pentaphenyltrisiloxane; INCI name: trimethylpentaphenyltrisiloxane), or the tetramethyltetraphenyltrisiloxane sold under the reference Dow Corning 554 Cosmetic Fluid by Dow Corning may also be used.

They correspond especially to formulae (III) and (ΙΙΓ) below:

Ph Ph Ph Me Ph Me

I I I I I I

Me-Si-O-Si-O— Si-Me Ph-Si-O-SrO— Si-Ph

\ \ \ \ \ \

Ph Me Ph ^JJJ^ Me Ph Me (ΠΓ) in which Me represents methyl, and Ph represents phenyl. c) phenyl silicone oils bearing at least one dimethicone fragment corresponding to formula (IV) below:

in which Me represents methyl, y is between 1 and 1000 and X represents -CH₂-CH(CH₃)(Ph). d) phenyl silicone oils corresponding to formula (V) below, and mixtures thereof:

in which:

- Ri to Rio, independently of each other, are saturated or unsaturated, linear, cyclic or branched, preferably saturated or unsaturated, linear or branched, C1-C30 hydrocarbon-based radicals,

- m, n, p and q are, independently of each other, integers between 0 and 900, with the proviso that the sum m+n+q is other than 0.

Preferably, the sum m+n+q is between 1 and 100. Preferably, the sum m+n+p+q is between 1 and 900 and preferably between 1 and 800. Preferably, q is equal to 0.

Preferably, Ri to Rio, independently of each other, represent a linear or branched C1-C30 alkyl radical, preferably C1-C20 and more particularly C1-C16 alkyl, or a monocyclic or polycyclic C₆-Ci4 and in particular C10-C13 aryl radical, or an aralkyl radical, the alkyl part of which is preferably C1-C3 alkyl.

Preferably, Ri to Rio may each represent a methyl, ethyl, propyl, butyl, isopropyl, decyl, dodecyl or octadecyl radical, or alternatively a phenyl, tolyl, benzyl or phenethyl radical. Ri to Rio may in particular be identical, and in addition may be a methyl radical.

According to a first more particular embodiment of formula (V), mention may be made of:

i) phenyl silicone oils optionally bearing at least one dimethicone fragment corresponding to formula (VI) below, and mixtures thereof:

in which:

- Ri to Re, independently of each other, are saturated or unsaturated, linear, cyclic or branched, preferably saturated or unsaturated, linear or branched, C1-C30 hydrocarbon-based radicals, a preferably C₆-Ci4 aryl radical or an aralkyl radical, the alkyl part of which is C1-C3 alkyl,

- m, n and p are, independently of each other, integers between 0 and 100, with the proviso that the sum n+m is between 1 and 100.

Preferably, Ri to R5, independently of each other, represent a C1-C30, preferably C1-C20 and in particular C1-C16, alkyl radical, or a C₆-Ci4 aryl radical which is monocyclic (preferably C₆) or polycyclic and in particular C10-C13, or an aralkyl radical (preferably the aryl part is C₆ aryl; the alkyl part is C1-C3 alkyl).

Preferably, Ri to 5 may each represent a methyl, ethyl, propyl, butyl, isopropyl, decyl, dodecyl or octadecyl radical, or alternatively a phenyl, tolyl, benzyl or phenethyl radical.

Ri to Re may in particular be identical, and in addition may be a methyl radical. Preferably, m = 1 or 2 or 3, and/or n = 0 and/or p = 0 or 1 can be applied, in formula (VI).

According to a particular embodiment, the non-volatile phenyl silicone oil is chosen from phenyl silicone oils bearing at least one dimethicone fragment.

Preferably, such oils correspond to compounds of formula (VI) in which:

A) m=0 and n and p are, independently of each other, integers between 1 and

100.

Preferably, Ri to Re are methyl radicals. According to this embodiment, the silicone oil is preferably chosen from a diphenyl dimethicone such as KF-54 from Shin-Etsu, KF54HV from Shin-Etsu, KF-50- 300CS from Shin-Etsu, KF-53 from Shin-Etsu or KF-50- lOOCS from Shin-Etsu.

B) p is between 1 and 100, the sum n+m is between 1 and 100, and n=0.

These phenyl silicone oils optionally bearing at least one dimethicone fragment correspond more particularly to formula (VII) below:

Me Me OR' Me

Me— Si- -O— Si- 0— Si- -O— Si-Me

P I m

Me Me Ph Me in which Me is methyl and Ph is phenyl, OR' represents a group -OSiMe3 and p is 0 or is between 1 and 1000, and m is between 1 and 1000. In particular, m and p are such that compound (VII) is a non- volatile oil.

According to a first embodiment of non- volatile phenyl silicone bearing at least one dimethicone fragment, p is between 1 and 1000 and m is more particularly such that compound (VII) is a non-volatile oil. Use may be made, for example, of trimethylsiloxyphenyl dimethicone, sold in particular under the reference Belsil PDM 1000 by the company Wacker.

According to a second embodiment of non-volatile phenyl silicone not bearing a dimethicone fragment, p is equal to 0 and m is between 1 and 1000, and in particular is such that compound (VII) is a non-volatile oil.

Phenyltrimethylsiloxytrisiloxane, sold in particular under the reference Dow Corning 556 Cosmetic Grade Fluid (DC556), may, for example, be used. ii) non-volatile phenyl silicone oils not bearing a dimethicone fragment corresponding to formula (VIII) below, and mixtures thereof:

in which:

- R, independently of each other, represent a saturated or unsaturated, linear, cyclic or branched, preferably saturated or unsaturated, linear or branched, C1-C30 hydrocarbon-based radical; more particularly, R represent a C1-C30 alkyl radical, an aryl radical, preferably a C₆-Ci4 aryl radical, or an aralkyl radical, the alkyl part of which is Ci- C₃ alkyl,

- m and n are, independently of each other, integers between 0 and 100, with the proviso that the sum n+m is between 1 and 100.

Preferably, R, independently of each other, represent a linear or branched Ci- C₃o and in particular a C1-C20, in particular C1-C16 alkyl radical, a monocyclic or polycyclic C₆-Ci4, and in particular Cio-Ci₃, aryl radical, or an aralkyl radical of which preferably the aryl part is C₆ aryl and the alkyl part is Ci-C₃ alkyl.

Preferably, the groups R may each represent a methyl, ethyl, propyl, butyl, isopropyl, decyl, dodecyl or octadecyl radical, or alternatively a phenyl, tolyl, benzyl or phenethyl radical.

The groups R may in particular be identical, and in addition may be a methyl radical.

Preferably, m = 1 or 2 or 3, and/or n = 0 and/or p = 0 or 1 can be applied, in formula (VIII).

According to a preferred embodiment, n is an integer between 0 and 100 and m is an integer between 1 and 100, with the proviso that the sum n+m is between 1 and 100, in formula (VIII). Preferably, R is a methyl radical.

According to one embodiment, a phenyl silicone oil of formula (VIII) with a viscosity at 25°C of between 5 and 1500 mm²/s (i.e. 5 to 1500 cSt), and preferably with a viscosity of between 5 and 1000 mm²/s (i.e. 5 to 1000 cSt), may be used. According to this embodiment, the non- volatile phenyl silicone oil is preferably chosen from phenyl trimethicones (when n=0) such as DC556 from Dow Corning (22.5 cSt), or else from diphenylsiloxyphenyl trimethicone oil (when m and n are between 1 and 100) such as KF56 A from Shin-Etsu, or the Silbione 70663 V30 oil from Rhone-Poulenc (28 cSt). The values in parentheses represent the viscosities at 25°C.

e) phenyl silicone oils optionally bearing at least one dimethicone fragment corresponding to the following formula, and mixtures thereof:

(IX)

in which:

Ri, R₂, Rs and Re, which may be identical or different, are an alkyl radical containing 1 to 6 carbon atoms,

R₃ and R₄, which may be identical or different, are an alkyl radical containing from 1 to 6 carbon atoms or an aryl radical (preferably C₆-Ci₄), with the proviso that at least one of R₃ and R₄ is a phenyl radical,

X is an alkyl radical containing from 1 to 6 carbon atoms, a hydroxyl radical or a vinyl radical,

n and p being an integer greater than or equal to 1 , chosen so as to give the oil a weight-average molecular weight of less than 200 000 g/mol, preferably less than 150 000 g/mol and more preferably less than 100 000 g/mol. f) and a mixture thereof.

2. Fluoro oils

According to another embodiment, the first non-volatile oil is chosen from fluoro oils. The fluoro oils that may be used according to the invention may be chosen from fluorosilicone oils, fluoro polyethers and fluorosilicones especially as described in document EP-A-847 752, and perfluoro compounds. According to the invention, the term "perfluoro compounds" means compounds in which all the hydrogen atoms have been replaced with fluorine atoms.

According to a preferred embodiment, the first fluoro oil according to the invention is chosen from perfluoro oils.

As examples of perfluoro oils that may be used in the invention, mention may be made of perfluorodecalins and perfluoroperhydrophenanthrenes.

According to one preferred embodiment, the fluoro oil is chosen from perfluoroperhydrophenanthrenes, and in particular the Fiflow^® products sold by the company Creations Couleurs. In particular, use may be made of the fluoro oil whose INCI name is perfluoroperhydrophenanthrene, sold under the reference Fiflow 220 by the company F2 Chemicals.

Preferably, the first oily phase comprises at least one first non- volatile oil chosen from the non-phenyl oils of formula (I), the phenyl oils of formula (II), especially (III), of formula (V), in particular (VI) or (VII), and also mixtures thereof.

3. Hydrocarbon-based oils

As indicated previously, a second embodiment consists in using, as first oil phase, at least one hydrocarbon-based oil, chosen in particular from non-volatile oils comprising not more than one free hydroxyl group or not comprising any, or from non- volatile oils comprising at least two free hydroxyl groups, or from apolar hydrocarbon- based non- volatile oils, or mixtures thereof.

These oils will be described in greater detail during the description of the second oily phase, and reference may be made thereto. Second oily phase

The second oily phase comprises at least one second non-volatile or volatile oil, which is immiscible with the first oil, at room temperature.

Preferably, the second oily phase comprises at least one second non-volatile oil, which is immiscible with the first oil(s), at room temperature.

This second oily phase may be the continuous phase or the dispersed phase.

The second oil(s) may advantageously be chosen from polar hydrocarbon- based non-volatile oils, in particular chosen from non-volatile oils comprising not more than one free hydroxyl group or not comprising any, or from non-volatile oils comprising at least two free hydroxyl groups, or from apolar hydrocarbon-based non-volatile oils, or mixtures thereof.

According to a second possibility, the second oil(s) are chosen from silicone oils that are immiscible with the first oil(s). The non-volatile silicone oils listed in the context of the definition of the first oily phase may be used as oil(s) of the second oily phase. Their description will not be repeated in this part of the text and reference may be made thereto, most particularly for the preferred silicones. 1. Polar non-volatile hydrocarbon-based oils

It may thus contain alcohol, ester, ether, carboxylic acid, amine and/or amide groups.

In particular, the hydrocarbon-based non-volatile polar oil may be chosen from the list of oils below, and mixtures thereof: a) non-volatile oils comprising not more than one free hydroxyl group or not comprising any

The second oil(s) may be chosen from non-volatile hydrocarbon-based oils comprising not more than one free hydroxyl group, or not comprising any. As examples of oils of this type, mention may be made of: i) Ester oils

* Hydrocarbon-based plant oils such as liquid triglycerides of fatty acids containing from 4 to 40 carbon atoms and more particularly from 4 to 24 carbon atoms.

Examples that may be mentioned include heptanoic or octanoic acid triglycerides, jojoba oil, sesame oil and ximenia seed oil, or mixtures thereof.

* Synthetic glycerides such as those of capric/caprylic acids, Cis-36 acid triglyceride (Dub TGI 24 from Stearinerie Dubois). * Monoesters or diesters obtained from a saturated or unsaturated, aromatic or non-aromatic mono carboxy lie or dicarboxylic fatty acid, in particular comprising from 4 to 40 and in particular from 4 to 24 carbon atoms, optionally comprising a free hydroxyl, on the one hand, and from a saturated or unsaturated, aromatic or non-aromatic monoalcohol or polyol, comprising from 2 to 40 and in particular from 3 to 24 carbon atoms, on the other hand; the number of carbon atoms (excluding the carbonyl group) being at least 12 and preferably at least 16, the ester comprising at most one free hydroxyl, if it contains any.

- As examples of monoesters or diesters, mention may be made of purcellin oil

(cetostearyl octanoate), isononyl isononanoate, C₁₂ to C₁₈ alkyl benzoate such as 2- octyldodecyl benzoate, 2-ethylhexyl palmitate, octyldodecyl neopentanoate, 2- octyldodecyl stearate, 2-octyldodecyl erucate, oleyl erucate, isostearyl isostearate, alcohol or polyalcohol, preferably diol, octanoates, decanoates or ricinoleates, isopropyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, 2-ethylhexyl palmitate, 2-hexyldecyl laurate, 2-octyldecyl palmitate, 2-octyldodecyl myristate and 2-diethylhexyl succinate; or mixtures thereof.

- Fatty acid monoesters and diesters, in particular of C4-C22 and preferably C₆- C22, and especially of octanoic acid, heptanoic acid, lanolic acid, oleic acid, lauric acid or stearic acid, and of C3-C6 glycol, for instance propylene glycol dioctanoate, propylene glycol monoisostearate or neopentyl glycol diheptanoate, are also suitable for use.

- Hydroxylated monoesters and diesters, preferably with a total carbon number ranging from 20 to 70, for instance isostearyl lactate, octyl hydroxystearate, octyldodecyl hydroxystearate or diisostearyl malate.

- C1-C4 monoesters of N-acylamino acids, for instance those of formula

R1CONR2CHR3 (CH₂)nCOOR₄ in which Rl represents a C5-C21 alkyl group, R₂, R3 and R₄, which may be identical or different, represent a C1-C4 alkyl group, R3 possibly being a hydrogen atom. For example, mention may be made of lauroyl isopropyl sarcosinate.

* Pentaerythritol esters of C6-C22 fatty monoacids or diacids, for instance the mixture of esters of pentaerythritol and of isostearic, capric, caprylic and adipic acids

(Supermol-L from Croda). * Polyesters comprising at least three ester functions, of saturated, unsaturated or aromatic, linear, branched or cyclic, optionally hydroxylated, C4-C40 monocarboxylic or polycarboxylic acids and, respectively, of C2-C40 and preferably C3-C40 polyols or monoalcohols; said polyester optionally comprising at least one free hydroxyl.

By way of example, mention may also be made of oils comprising three ester functions, of a monohydroxylated acid comprising three carboxylic functions, and of a C₂- C4 monoalcohol, in particular triethyl citrate.

By way of example, mention may be made of linear fatty acid esters with a total carbon number ranging from 35 to 70, for instance pentaerythrityl tetrapelargonate (MW = 697 g/mol).

Esters of branched fatty alcohols or of branched fatty acids, for instance, especially, triisoarachidyl citrate (MW = 1033.76 g/mol), pentaerythrityl tetraisononanoate (MW = 697 g/mol), glyceryl triisostearate (MM = 891 g/mol), pentaerythrityl tetraisostearate (MW = 1202 g/mol), poly(2-glyceryl) tetraisostearate (MW = 1232 g/mol), and also those described in patent application EP-A-0 955 039, for instance glyceryl tris(2- decyl)tetradecanoate (MW = 1143 g/mol) or pentaerythrityl tetrakis(2-decyl)tetradecanoate (MW = 1538 g/mol), are also suitable for use.

Mention may also be made of esters of aromatic acids and of alcohols comprising 4 to 22 atoms, such as tridecyl trimellitate (MW = 757 g/mol).

Use may also be made of polyesters resulting from the esterification of at least one hydroxylated carboxylic acid triglyceride with an aliphatic monocarboxylic acid and with an aliphatic dicarboxylic acid, which is optionally unsaturated, for instance the succinic acid and isostearic acid castor oil sold under the reference Zenigloss by Zenitech. ii) saturated or unsaturated, linear or branched monohydroxylated fatty alcohols containing from 8 to 30 carbon atoms and more advantageously from 12 to 26 carbon atoms, for instance octyldodecanol, 2-butyloctanol, 2-hexyldecanol, 2- undecylpentadecanol or oleyl alcohol; iii) saturated or unsaturated C12-C26 and preferably C12-C22 fatty acids, such as oleic acid, linoleic acid and linolenic acid, and also mixtures thereof; iv) dialkyl carbonates, the two alkyl chains possibly being identical or different, such as dicaprylyl carbonate sold under the name Cetiol CC® by Cognis; and v) vinylpyrrolidone copolymers such as the vinylpyrrolidone/l-hexadecene copolymer, Antaron V-216 sold or manufactured by the company ISP (MW = 7300 g/mol). b) Non- volatile oils comprising at least two free hydroxyl groups:

The second oil(s) may be chosen from non-volatile hydrocarbon-based oils comprising at least two free hydroxyl groups and preferably at least three free hydroxyl groups.

According to a first advantageous variant of the invention, the second oil(s) also comprise at least one ester function.

Examples of suitable oils that may be mentioned include:

* hydrocarbon-based plant oils such as liquid triglycerides of fatty acids containing from 4 to 40 carbon atoms and comprising at least two free hydroxyl groups and advantageously at least three free hydroxyl groups, for instance castor oil;

* hydroxylated esters, preferably with a total carbon number ranging from 35 to 70, for instance poly(2-glyceryl) triisostearate (MW = 965 g/mol), poly(2-glyceryl) isostearate; poly(2-glyceryl) diisostearate; poly(3 -glyceryl) diisostearate, glyceryl stearate; glyceryl isostearate; or mixtures thereof;

* esters of a diol dimer and of a diacid dimer of general formula HO-R^OCO-R^COO-P -VOH, in which:

R¹ represents a diol dimer residue obtained by hydrogenation of dilinoleic diacid,

R² represents a hydrogenated dilinoleic diacid residue, and

h represents an integer ranging from 1 to 9,

especially the esters of dilinoleic diacids and of dilinoleyl diol dimers sold by the company Nippon Fine Chemical under the trade names Lusplan DD-DA5® and DD- DA7®, and

* polyesters obtained by condensation of an unsaturated fatty acid dimer and/or trimer and of diol, in particular such as of dilinoleic acid and of 1,4-butanediol. Mention may especially be made in this respect of the polymer sold by Biosynthis under the name Viscoplast 14436H (INCI name: dilinoleic acid/butanediol copolymer), or else copolymers of polyols and of dimer diacids, and esters thereof, such as Hailucent ISDA. According to a second advantageous variant of the invention, the second hydrocarbon-based oil(s) are chosen from polyhydroxylated alcohols, preferably of C₂-Cs and more preferably of C3-C6, comprising two to three hydroxyl groups, such as glycerol, propylene glycol, pentylene glycol, 1,3-butylene glycol, dipropylene glycol or diglycerol, and a mixture thereof.

2. Apolar non-volatile hydrocarbon-based oils

The O/O emulsion according to the invention may also comprise, as oil(s) present in the second oily phase, at least one apolar non-volatile hydrocarbon-based oil.

These oils may be of plant, mineral or synthetic origin.

For the purposes of the present invention, the term "apolar oil" means an oil formed essentially from, or even constituted by, carbon and hydrogen atoms, and not containing any oxygen, nitrogen, silicon or fluorine atoms.

Advantageously, apolar oil, preferably a hydrogenated apolar oil contains only carbon atoms and hydrogen.

Preferably, the non-volatile apolar hydrocarbon-based oil may be chosen from linear or branched hydrocarbons of mineral or synthetic origin, such as:

- liquid paraffin or derivatives thereof,

- squalane,

- isoeicosane,

- naphthalene oil,

- polybutenes, for instance Indopol H-100 (molar mass or MW = 965 g/mol), Indopol H-300 (MW = 1340 g/mol) and Indopol H-1500 (MW = 2160 g/mol) sold or manufactured by the company Amoco,

- hydrogenated or non-hydrogenated polyisobutenes, for instance Parleam^® sold by the company Nippon Oil Fats, Panalane H-300 E sold or manufactured by the company Amoco (MW = 1340 g/mol), Viseal 20000 sold or manufactured by the company Synteal (MW = 6000 g/mol) and Rewopal PIB 1000 sold or manufactured by the company Witco (MW = 1000 g/mol), or alternatively Parleam Lite sold by NOF Corporation,

- decene/butene copolymers, polybutene/polyisobutene copolymers, especially Indopol L-14,

- polydecenes and hydrogenated polydecenes especially such as: Puresyn 10

(MW = 723 g/mol) and Puresyn 150 (MW = 9200 g/mol) sold or manufactured by the company Mobil Chemicals, or alternatively Puresyn 6 sold by ExxonMobil Chemical),

- and mixtures thereof. 3. Volatile silicone or hydrocarbon-based oils

The O/O emulsion according to the invention may also comprise, as oil(s) present in the second oily phase, at least one volatile silicone or hydrocarbon-based oil.

According to the invention, these volatile oils especially facilitate the application of the composition to the skin, the lips or the integuments.

These oils may be hydrocarbon-based oils or silicone oils optionally comprising alkyl or alkoxy groups that are pendent or at the end of the silicone chain, or a mixture of these oils.

As volatile silicone oils that may be used in the invention, mention may be made of linear or cyclic silicone oils with a viscosity at room temperature of less than 8 cSt and especially containing from 2 to 7 silicon atoms, these silicones optionally comprising alkyl or alkoxy groups containing from 1 to 10 carbon atoms. As volatile silicone oils that may be used in the invention, mention may be made especially of octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, heptamethylhexyltrisiloxane, heptamethyloctyltrisiloxane, hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane and dodecamethylpentasiloxane, and mixtures thereof.

As volatile hydrocarbon-based oils that may be used in the invention, mention may be made of volatile hydrocarbon-based oils containing from 8 to 16 carbon atoms, and mixtures thereof, especially branched Cs-Ci6 alkanes such as Cs-Ci6 isoalkanes (also known as isoparaffms), isododecane, isodecane, isohexadecane and, for example, the oils sold under the trade names Isopar or Permethyl, and mixtures thereof. Use is preferably made of isododecane (Permethyl 99 A), Cs-Ci6 isoparaffms such as Isopar L, E, G or H, or mixtures thereof, optionally combined with decamethyltetrasiloxane or with cyclop entasiloxane.

Use may also be made of volatile fluoro oils.

The emulsion according to the invention more particularly comprises from 5% to 95% by weight and preferably from 30%> to 70%> by weight of the oil(s) of the first oily phase, relative to the weight of the emulsion.

The emulsion according to the invention more particularly comprises from 5% to 95%o by weight and preferably from 30%> to 70%> by weight of the oil(s) of the second oily phase, relative to the weight of the emulsion.

Preferably, the second oily phase comprises at least one non- volatile oil.

According to this variant, the content of volatile oil of the second oily phase represents from 0.1% to 30% by weight relative to the weight of the emulsion.

In accordance with an advantageous embodiment of the invention, the weight ratio of the oil(s) of the first oily phase relative to the oil(s) of the second oily phase represents from 5/95 to 95/5 and preferably from 30/70 to 70/30. According to a first embodiment of the invention, the O/O emulsion comprises a first oily phase containing at least a first oil chosen from non-volatile silicone oils and a second oily phase containing at least a second oil chosen from non- volatile apolar hydrocarbon-based oils.

Preferably, the apolar oils are chosen from oils with a viscosity of at least 50 cPs, preferably of at least 60 cPs. According to a particularly advantageous embodiment of the invention, the apolar non-volatile oil(s) are chosen from hydrogenated or non- hydrogenated polydecenes and hydrogenated or non-hydrogenated polybutenes, or mixtures thereof. According to a second embodiment of the invention, the O/O emulsion comprises a first oily phase containing at least a first oil chosen from non-phenyl nonvolatile silicone oils or phenyl non-volatile silicone oils bearing at least one dimethicone fragment, and a second oily phase containing at least a second oil chosen from non- volatile hydrocarbon-based oils comprising not more than one free hydroxyl group or not comprising any.

As regards the non-phenyl non-volatile silicone oils, they may preferably be chosen from the silicone oils of formula (Γ).

As regards the non- volatile phenyl silicone oils comprising at least one dimethicone fragment, they may be chosen from the compounds of formula (I) with radicals R such that the silicone is phenylated and comprises at least one dimethicone fragment; (II) with radicals R such that the silicone is phenylated and comprises at least one dimethicone fragment; (IV); (V) with non-zero p, in particular (VI) with non-zero p and especially the variants (A) and (B); (VII) with non-zero p, (IX) with radicals R such that the silicone is phenylated and comprises at least one dimethicone fragment, or mixtures thereof.

More particularly, the second oil(s) are chosen from non-volatile ester oils i), fatty alcohols ii) and mixtures thereof.

According to a third embodiment of the invention, the O/O emulsion comprises a first oily phase containing at least a first oil chosen from non-volatile silicone oils and a second oily phase containing at least a second oil chosen from non- volatile hydrocarbon- based oils comprising at least two free hydroxyl groups and preferably at least three free hydroxyl groups. More particularly, said non-volatile hydrocarbon-based oils comprise at least one carboxylic ester group. Non-volatile hydrocarbon-based oils comprising three ester functions, of a monohydroxylated acid comprising three carboxylic functions and of a C2-C4 monoalcohol, are also suitable in this variant, as second oil(s).

According to a fourth preferred embodiment of the invention, the O/O emulsion comprises a first oily phase containing at least a first oil chosen from phenyl nonvolatile silicone oils not bearing a dimethicone fragment, and a second oily phase containing at least a second oil chosen from non-volatile hydrocarbon-based oils comprising at least two free hydroxyl groups and preferably at least three free hydroxyl groups, or from non-volatile apolar hydrocarbon-based oils and even more particularly at least a second oil chosen from non- volatile hydrocarbon-based oils comprising at least two free hydroxyl groups, and preferably at least three free hydroxyl groups.

As regards the non-volatile phenyl silicone oils not bearing a dimethicone fragment, they are more particularly chosen from (I), with radicals R such that the silicone has no dimethicone fragment; (II) with radicals R such that the silicone has no dimethicone fragment, in particular formulae (III) and (ΠΓ); (V) with p = 0; (VI) with p=0; (VII) with p=0; (VIII); (IX) with radicals R such that the silicone has no dimethicone fragment; or mixtures thereof.

According to a particular embodiment of the invention, the apolar non- volatile oil(s) are chosen from hydrogenated or non-hydrogenated polydecenes and hydrogenated or non-hydrogenated polybutenes, and mixtures thereof.

Preferably, the non- volatile apolar hydrocarbon-based oils are chosen from oils with a viscosity of at least 50 cPs, in particular of at least 60 cPs.

In accordance with a fifth embodiment of the invention, the O/O emulsion comprises at least a first polar non- volatile hydrocarbon-based oil and at least a second volatile or non-volatile oil, preferably from apolar non- volatile hydrocarbon-based oils.

Preferably, the first polar non-volatile hydrocarbon-based oil(s) are chosen from ester oils comprising not more than one free hydroxyl group or not comprising any, and preferably from oils also comprising at least three ester functions.

The first polar non-volatile hydrocarbon-based oil(s) may also be chosen from oils comprising at least two free hydroxyl groups and at least one ester function, or from polyhydroxylated alcohols, and also mixtures thereof.

The second non- volatile apolar oil(s) are preferably chosen from hydrogenated or non-hydrogenated polydecenes, hydrogenated or non-hydrogenated polybutenes and hydrogenated or non-hydrogenated polyisobutenes, or mixtures thereof.

In accordance with a sixth embodiment of the invention, the O/O emulsion comprises a first oily phase comprising at least one non-phenyl non- volatile silicone oil and a second oily phase containing at least one phenyl non-volatile silicone oil optionally bearing a dimethicone fragment, or at least one volatile silicone oil. In accordance with a final embodiment of the invention, the O/O emulsion comprises a first oily phase comprising at least one non-volatile phenyl silicone oil not bearing a dimethicone fragment, and a second oily phase containing at least one nonvolatile phenyl silicone oil bearing at least one dimethicone fragment, or at least one volatile silicone oil.

Preferably, the first non- volatile phenyl silicone oil(s) not bearing a dimethicone fragment are chosen from the compounds of formula (II). As regards the second non- volatile silicone oil(s) bearing at least one dimethicone fragment, they are advantageously chosen from the oils i) of formula (VI), more particularly B) with, for example, the silicones of formula (VII).

As indicated previously, the O/O emulsion may comprise at least one volatile oil. More particularly, the first oily phase and/or the second oily phase may comprise at least one volatile oil. It should be noted that the second oily phase may comprise only volatile oils. Reference may be made to that which has been detailed previously regarding the nature of these oils.

STRUCTURING AGENT

As indicated previously, the O/O emulsion according to the present invention comprises at least one structuring agent chosen from waxes, pasty compounds, polymeric thickeners and mineral thickeners, and mixtures thereof.

The structuring agent may be incorporated into one and/or the other of the oily phases of the O/O emulsion according to the invention. Preferably, the structuring agent is present in the continuous oily phase of the emulsion.

The structuring agent is more particularly chosen as a function of the oil(s) into which it is incorporated.

More particularly, the structuring agent is chosen such that it is compatible with the oil into which it is incorporated.

WAXES

The emulsion according to the invention may comprise at least one wax.

More particularly, the wax is chosen such that it is compatible with the oil into which it is incorporated. Thus, use is preferably made of at least one wax which, when it is mixed with at least one oil (first oil(s) or second oil(s)) (wax/oil proportion: 10/90; 10 g sample) at a temperature greater than or equal to the melting point of said wax, leads to the production of a homogeneous mixture.

The term "wax" is understood, within the meaning of the present invention, to mean a lipophilic compound, which is solid at room temperature (25°C), with a reversible solid/liquid change of state, which has a melting point of greater than or equal to 30°C, which may be up to 120°C.

The melting point of the wax may be measured using a differential scanning calorimeter (DSC), for example the calorimeter sold under the name DSC 30 by the company Mettler.

Preferably, the measuring protocol is as follows:

A sample of 5 mg of wax placed in a crucible is subjected to a first temperature rise ranging from -20°C to 100°C, at a heating rate of 10°C/minute, is then cooled from 100°C to -20°C at a cooling rate of 10°C/minute and is finally subjected to a second temperature rise ranging from -20°C to 100°C at a heating rate of 5°C/minute. During the second temperature rise, the variation in the difference in power absorbed by the empty crucible and by the crucible containing the sample of wax is measured as a function of the temperature. The melting point of the compound is the temperature value corresponding to the top of the peak of the curve representing the variation in the difference in power absorbed as a function of the temperature.

The wax may especially have a hardness ranging from 0.05 MPa to 15 MPa and preferably ranging from 6 MPa to 15 MPa. The hardness is determined by measuring the compressive force, measured at 20°C using the texture analyser sold under the name ΤΑ-ΤΧ2Ϊ by the company Rheo, equipped with a stainless-steel cylinder with a diameter of 2 mm, travelling at a measuring speed of 0.1 mm/second, and penetrating the wax to a penetration depth of 0.3 mm. The waxes may be hydrocarbon-based waxes, silicone waxes or fluoro waxes, and may be of plant, mineral, animal and/or synthetic origin. In particular, the waxes have a melting point of greater than 30°C and better still greater than 45°C.

Apolar wax

For the purposes of the present invention, the term "apolar wax" means a wax whose solubility parameter 5a at 25°C as defined below is equal to 0 (J/cm³)½.

The apolar waxes are in particular hydrocarbon-based waxes formed solely from carbon and hydrogen atoms, and free of heteroatoms such as N, O, Si and P.

In particular, the term "apolar wax" means a wax that is formed solely from apolar wax, rather than a mixture also comprising other types of waxes that are not apolar waxes.

As illustrations of apolar waxes that are suitable for use in the invention, mention may be made especially of hydrocarbon-based waxes, for instance microcrystalline waxes, paraffin waxes, ozokerite, polymethylene waxes, polyethylene waxes and microwaxes, especially polyethylene waxes.

Polyethylene waxes that may be mentioned include Performalene 500-L Polyethylene and Performalene 400 Polyethylene sold by New Phase Technologies, and Asensa SC 211 sold by Honeywell.

A polymethylene wax that may be mentioned is Cirebelle 108 sold by Cirebelle.

An ozokerite that may be mentioned is Ozokerite Wax SP 1020 P.

As microcrystalline waxes that may be used, mention may be made of Multiwax W 445® sold by the company Sonneborn, and Microwax HW® and Base Wax 30540® sold by the company Paramelt.

As microwaxes that may be used in the O/O emulsions according to the invention as apolar wax, mention may be made especially of polyethylene microwaxes such as those sold under the names Micropoly 200®, 220®, 220L® and 250S® by the company Micro Powders. Polar wax

For the purposes of the present invention, the term "polar wax" means a wax whose solubility parameter 5a at 25°C is other than 0 (J/cm³)½. In particular, the term "polar wax" means a wax whose chemical structure is formed essentially from, or even constituted by, carbon and hydrogen atoms, and comprising at least one highly electronegative heteroatom such as an oxygen, nitrogen, silicon or phosphorus atom.

The definition and calculation of the solubility parameters in the Hansen three- dimensional solubility space are described in the article by CM. Hansen: "The three dimensional solubility parameters", J. Paint Technol. 39, 105 (1967).

According to this Hansen space:

- 5D characterizes the London dispersion forces derived from the formation of dipoles induced during molecular impacts;

- δρ characterizes the Debye interaction forces between permanent dipoles and also the Keesom interaction forces between induced dipoles and permanent dipoles;

- 5h characterizes the specific interaction forces (such as hydrogen bonding, acid/base, donor/acceptor, etc.); and

- 5a is determined by the equation: 5a = (δρ² + 5h²)^½.

The parameters δρ, 5h, 5D and 5a are expressed in (J/cm³)^½.

The polar waxes may especially be hydrocarbon-based, fluoro or silicone waxes, and preferably hydrocarbon-based or silicone waxes.

The term "silicone wax" means an oil comprising at least one silicon atom, especially comprising Si-0 groups.

The term "hydrocarbon-based wax" means a wax formed essentially from, or even constituted by, carbon and hydrogen atoms, and optionally oxygen and nitrogen atoms, and that does not contain any silicon or fluorine atoms. It may contain alcohol, ester, ether, carboxylic acid, amine and/or amide groups.

Hydrocarbon-based waxes

According to a first preferred embodiment, the polar wax is a hydrocarbon- based wax.

As a hydrocarbon-based polar wax, a wax chosen from ester waxes and alcohol waxes is in particular preferred.

According to the invention, the term "ester wax" means a wax comprising at least one ester function. The ester oils may also be hydroxylated. According to the invention, the term "alcohol wax" means a wax comprising at least one alcohol function, i.e. comprising at least one free hydroxy 1 (OH) group.

The following may especially be used as ester wax:

- ester waxes such as those chosen from:

i) waxes of formula R1COOR2 in which Rl and R2 represent linear, branched or cyclic aliphatic chains, the number of atoms of which varies from 10 to 50, which may contain a heteroatom such as O, N or P and the melting point of which varies from 25 °C to 120°C. In particular, use may be made, as an ester wax, of a C20-C40 alkyl (hydroxystearyloxy)stearate (the alkyl group comprising from 20 to 40 carbon atoms), alone or as a mixture, or a C20-C40 alkyl stearate. Such waxes are especially sold under the names Kester Wax K 82 P®, Hydroxypoly ester K 82 P®, Kester Wax K 80 P® and Kester Wax K82H by the company Koster Keunen.

Use may also be made of a glycol and butylene glycol montanate (octacosanoate) such as the wax Licowax KPS Flakes (INCI name: glycol montanate) sold by the company Clariant.

ii) Bis(l,l,l-trimethylolpropane) tetrastearate, sold under the name Hest 2T- 4S® by the company Heterene.

iii) dicarboxylic acid diester waxes of general formula R3-(-OCO-R4-COO-R5), in which R3 and R5 are identical or different, preferably identical and represent a C4-C30 alkyl group (alkyl group comprising from 4 to 30 carbon atoms) and R4 represents a linear or branched C4-C30 aliphatic group (alkyl group comprising from 4 to 30 carbon atoms) which may or may not contain one or more unsaturated groups. Preferably, the C4-C30 aliphatic group is linear and unsaturated.

iv) Mention may also be made of the waxes obtained by catalytic hydrogenation of animal or plant oils having linear or branched C8-C32 fatty chains, for example such as hydrogenated jojoba oil, hydrogenated sunflower oil, hydrogenated castor oil, hydrogenated coconut oil, and also the waxes obtained by hydrogenation of castor oil esterified with cetyl alcohol, such as those sold under the names Phytowax ricin 16L64® and 22L73® by the company Sophim. Such waxes are described in patent application FR- A-2 792 190. Mention may be made, as waxes obtained by hydrogenation of olive oil esterified with stearyl alcohol, of those sold under the name Phytowax Olive 18 L 57. v) Waxes corresponding to the partial or total esters, preferably total esters, of a saturated, optionally hydroxylated C16-C30 carboxylic acid with glycerol. The term "total esters" means that all the hydroxyl functions of glycerol are esterified.

Examples that may be mentioned include trihydroxystearine (or glyceryl trihydroxystearate), tristearine (or glyceryl tristearate) and tribehenine (or glyceryl tribehenate), alone or as a mixture. Among the suitable compounds, mention may be made of triesters of glycerol and of 12-hydroxystearic acid, or hydrogenated castor oil, for instance Thixcin R and Thixcin E sold by Elementis Specialties.

vi) Mention may also be made of beeswax, synthetic beeswax, polyglycerolated beeswax, carnauba wax, candelilla wax, oxypropylenated lanolin wax, rice bran wax, ouricury wax, esparto grass wax, cork fibre wax, sugar cane wax, Japan wax, sumac wax, montan wax, orange wax, laurel wax and hydrogenated jojoba wax, and mixtures thereof.

According to another embodiment, the polar wax may be an alcohol wax.

Alcohol waxes that may be mentioned include alcohols, which are preferably linear and preferably saturated, comprising from 16 to 60 carbon atoms, with a melting point of between 25 and 120°C. Examples that may be mentioned include the wax Performacol 550-L Alcohol from New Phase Technologies, stearyl alcohol, cetyl alcohol, myristyl alcohol, palmityl alcohol, behenyl alcohol, erucyl alcohol or arachidyl alcohol, or mixtures thereof.

Silicone waxes

The term "silicone wax" means an oil comprising at least one silicon atom, and in particular comprising Si-0 groups.

Among the commercial silicone waxes of this type, mention may be made especially of those sold under the names Abilwax 9810 (Goldschmidt), KF910 and KF7002 (Shin-Etsu), or 176-11481 (General Electric).

The silicone waxes that may be used may also be alkyl or alkoxy dimethicones, and also (C2o-C₆o)alkyl dimethicones, in particular (C3o-C4₅)alkyl dimethicones, such as the silicone wax sold under the name SF-1642 by the company GE-Bayer Silicones or C30-45 alkyldimethylsilyl polypropylsilsesquioxane under the name SW-8005^® C30 Resin Wax sold by the company Dow Corning. Mention may also be made of silicone waxes obtained by esterification with a (poly)alkoxylated silicone, such as silicone beeswax, silicone candelilla wax or silicone carnauba wax.

When the emulsion comprises any, the content of wax(es) is preferably between 0.1% and 20%, preferentially 0.5% and 15% and more particularly 1% and 10% by weight relative to the total weight of the oil(s) into which they are incorporated.

PASTY COMPOUNDS

The emulsion according to the invention may comprise at least one compound that is pasty at 25°C and atmospheric pressure.

More particularly, the pasty compound is chosen such that it is compatible with the oil into which it is incorporated.

Thus, use is preferably made of at least one pasty compound which, when it is mixed with at least one oil (first oil(s) or second oil(s)) (pasty compound/oil proportion: 10/90; 10 g sample) at a temperature greater than or equal to the melting point of said pasty compound, leads to the production of a homogeneous mixture.

It should be noted that this pasty compound is water-immiscible.

For the purposes of the present invention, the term "pasty" refers to a compound that undergoes a reversible solid/liquid change of state, having anisotropic crystalline organization in the solid state, and comprising, at a temperature of 23°C, a liquid fraction and a solid fraction.

In other words, the starting melting point of the pasty compound can be less than 23°C. The liquid fraction of the pasty compound, measured at 23°C, can represent from 9% to 97% by weight of the pasty compound. This liquid fraction at 23 °C preferably represents between 15% and 85% and more preferably between 40% and 85% by weight.

Within the context of the invention, the melting point corresponds to the temperature of the most endothermic peak observed in thermal analysis (DSC) as described in the standard ISO 11357-3; 1999. The melting point of a pasty compound may be measured using a differential scanning calorimeter (DSC), for example the calorimeter sold under the name MDSC 2920 by the company TA Instruments.

The measuring protocol is as follows: A sample of 5 mg of pasty compound placed in a crucible is subjected to a first temperature rise ranging from -20°C to 100°C, at a heating rate of 10°C/minute, is then cooled from 100°C to -20°C at a cooling rate of 10°C/minute and is finally subjected to a second temperature rise ranging from -20°C to 100°C at a heating rate of 5°C/minute. During the second temperature rise, the variation in the difference in power absorbed by the empty crucible and by the crucible containing the sample of pasty fatty substance is measured as a function of the temperature. The melting point of the pasty compound is the temperature value corresponding to the top of the peak of the curve representing the variation in the difference in power absorbed as a function of the temperature.

The liquid fraction by weight of the pasty compound at 23°C is equal to the ratio of the heat of fusion consumed at 23°C to the heat of fusion of the pasty compound.

The heat of fusion of the pasty compound is the heat consumed by the compound in order to pass from the solid state to the liquid state. The pasty compound is said to be in the solid state when all of its mass is in crystalline solid form. The pasty compound is said to be in the liquid state when all of its mass is in liquid form.

The heat of fusion of the pasty compound is equal to the area under the curve of the thermogram obtained using a differential scanning calorimeter (DSC), such as the calorimeter sold under the name MDSC 2920 by the company TA Instrument, with a temperature rise of 5°C or 10°C per minute, according to the standard ISO 1 1357-3; 1999.

The heat of fusion of the pasty compound is the amount of energy required to make the pasty compound change from the solid state to the liquid state. It is expressed in J/g.

The heat of fusion consumed at 23°C is the amount of energy absorbed by the sample to change from the solid state to the state that it has at 2°C, formed from a liquid fraction and a solid fraction.

The liquid fraction of the pasty compound measured at 32°C preferably represents from 30% to 100% by weight of the pasty compound, preferably from 50%> to 100% and more preferably from 60% to 100% by weight of the pasty compound. When the liquid fraction of the pasty compound measured at 32°C is equal to 100%, the temperature of the end of the melting range of the pasty compound is less than or equal to 32°C.

The liquid fraction of the pasty compound measured at 32°C is equal to the ratio of the heat of fusion consumed at 32°C to the heat of fusion of the pasty compound. The heat of fusion consumed at 32°C is calculated in the same way as the heat of fusion consumed at 23°C.

The pasty compound is more particularly chosen as a function of the oil(s) into which it is incorporated.

Thus, use is preferably made of at least one pasty compound which, when it is mixed with at least one oil (first oil(s) or second oil(s)) (pasty compound/oil proportion: 25/75; 10 g sample) at a temperature greater than or equal to the melting point of said wax until a homogeneous mixture is obtained, which is then allowed to cool to 20°C, does not reveal any oil phase separation greater than 20% by volume, more particularly 10% by volume.

The pasty compound may in particular be chosen from synthetic pasty compounds and fatty substances of plant origin. The pasty compound(s) may be chosen in particular from:

lanolin and derivatives thereof, such as lanolin alcohol, oxyethylenated lanolins, acetylated lanolin, lanolin esters such as isopropyl lanolate, and oxypropylenated lanolins;

- petroleum jelly (also known as petrolatum);

- polyol ethers chosen from C2-C4 polyalkylene glycol pentaerythrityl ethers, fatty alcohol ethers of sugars, and mixtures thereof. For example, mention may be made of polyethylene glycol pentaerythrityl ether comprising 5 oxy ethylene units (5 OE) (CTFA name: PEG-5 Pentaerythrityl Ether), polypropylene glycol pentaerythrityl ether comprising five oxypropylene (5 OP) units (CTFA name: PPG-5 Pentaerythrityl Ether) and mixtures thereof, and more especially the mixture PEG-5 Pentaerythrityl Ether, PPG-5 Pentaerythrityl Ether and soybean oil, sold under the name Lanolide by the company Vevy, which is a mixture in which the constituents are in a 46/46/8 weight ratio: 46% PEG-5 pentaerythrityl ether, 46% PPG-5 pentaerythrityl ether and 8% soybean oil,

- polymeric or non-polymeric silicone compounds,

- polymeric or non-polymeric fluoro compounds,

- vinyl polymers, especially:

- olefin homopolymers and copolymers, - hydrogenated diene homopolymers and copolymers,

linear or branched oligomers, which are homopolymers or copolymers of alkyl (meth)acrylates preferably containing a C8-C30 alkyl group,

- oligomers, which are homopolymers and copolymers of vinyl esters containing C8-C30 alkyl groups, and

- oligomers, which are homopolymers and copolymers of vinyl ethers containing C8-C30 alkyl groups,

liposoluble poly ethers resulting from polyetherification between one or more C2-C100 and preferably C2-C50 diols,

Among the liposoluble polyethers that are particularly considered are copolymers of ethylene oxide and/or of propylene oxide with C6-C30 long-chain alkylene oxides, more preferably such that the weight ratio of the ethylene oxide and/or of the propylene oxide to the alkylene oxides in the copolymer is from 5:95 to 70:30. In this family, mention will be made especially of copolymers such as long-chain alkylene oxides arranged in blocks with an average molecular weight from 1000 to 10 000, for example a polyoxyethylene/polydodecyl glycol block copolymer such as the ethers of dodecanediol (22 mol) and of polyethylene glycol (45 OE) sold under the brand name Elfacos ST9 by Akzo Nobel,

- esters and polyesters,

Among the esters, the following are especially considered:

- esters of a glycerol oligomer, especially diglycerol esters, in particular condensates of adipic acid and of diglycerol, for which some of the hydroxyl groups of the glycerols have reacted with a mixture of fatty acids such as stearic acid, capric acid, isostearic acid and 12-hydroxystearic acid, for instance bis-diglyceryl polyacyladipate-2 sold under the reference Softisan^® 649 by the company Cremer Oleo,

- vinyl ester homopolymers bearing C8-C30 alkyl groups, such as polyvinyl laurate (sold especially under the reference Mexomer PP by the company Chimex),

- the arachidyl propionate sold under the brand name Waxenol 801 by Alzo,

- phytosterol esters,

- fatty acid triglycerides and derivatives thereof,

- pentaerythritol esters, esters of diol dimer and of diacid dimer, where appropriate esterified on the free alcohol or acid function(s) thereof with acid or alcohol radicals, especially dimer dilinoleate esters; such esters may be chosen especially from the esters having the following INCI nomenclature: bis-behenyl/isostearyl/phytosteryl dimer dilinoleyl dimer dilinoleate (Plandool G), phytosteryl/isostearyl/cetyl/stearyl/behenyl dimer dilinoleate (Plandool H or Plandool S), and mixtures thereof,

- butters of plant origin, such as mango butter, such as the product sold under the reference Lipex 203 by the company Aarhuskarlshamn, shea butter, in particular the product whose INCI name is Butyrospermum Parkii Butter, such as the product sold under the reference Sheasoft® by the company Aarhuskarlshamn, cupuacu butter (Rain Forest RF3410 from the company Beraca Sahara), murumuru butter (Rain Forest RF3710 from the company Beraca Sahara), cocoa butter; and also orange wax, for instance the product sold under the reference Orange Peel Wax by the company Koster Keunen,

- totally or partially hydrogenated plant oils, for instance hydrogenated soybean oil, hydrogenated coconut oil, hydrogenated rapeseed oil, mixtures of hydrogenated plant oils such as the mixture of hydrogenated soybean, coconut, palm and rapeseed plant oil, for example the mixture sold under the reference Akogel® by the company Aarhuskarlshamn (INCI name: Hydrogenated Vegetable Oil), the product sold under the reference Cegesoft® HF 52 from BASF (INCI name Hydrogenated Vegetable Oil), the trans-isomerized partially hydrogenated jojoba oil manufactured or sold by the company Desert Whale under the commercial reference Iso-Jojoba-50®, partially hydrogenated olive oil, for instance the compound sold under the reference Beurrolive by the company Soliance,

- hydrogenated castor oil esters, such as hydrogenated castor oil dimer dilinoleate, for example Risocast-DA-L sold by Kokyu Alcohol Kogyo, and hydrogenated castor oil isostearate, for example Salacos HCISV-L sold by Nisshin Oillio,

and mixtures thereof.

Preferably, the pasty compounds that are suitable for use in the invention are chosen from hydrocarbon-based compounds and comprise, besides carbon and hydrogen atoms, at least oxygen atoms. Thus, preferably, the pasty compounds therefore do not comprise any silicon atoms or any fluorine atoms. According to a preferred embodiment, the pasty compound(s) are chosen from lanolin and derivatives thereof, esters of glycerol oligomers, butters of plant origin, totally or partially hydrogenated plant oils, and hydrogenated castor oil esters, or mixtures thereof. When the emulsion comprises at least one pasty compound, the content of pasty compound(s) is preferably between 0.1% and 30%> by weight, preferentially 0.5%> and 20% by weight and more particularly 1% and 10% by weight relative to the total weight of the oil(s) into which they are incorporated. POLYMERIC THICKENERS

Among the polymeric thickeners that are suitable for use, mention may be made of organopolysiloxane elastomers, semi-crystalline polymers, hydrocarbon-based polyamides, silicone polyamides and dextrin esters, and also mixtures thereof.

More particularly, the polymeric thickener is chosen such that it is compatible with the oil into which it is incorporated.

Thus, use is preferably made of at least one polymeric thickener which, when it is mixed with at least one oil (first oil(s) or second oil(s)) (polymeric thickener/oil proportion: 10/90; 10 g sample) at a temperature greater than or equal to the melting point of said polymeric thickener, leads to the production of a homogeneous mixture.

The choice of the polymeric thickener may advantageously be made as a function of the nature of the oils present. For example, if the oil is hydrocarbon-based, it may be advantageous to choose a hydrocarbon-based polymeric thickener, and if the oil is silicone-based, it may be advantageous to choose a silicone polymeric thickener.

If the O/O emulsion comprises any, the content of polymeric thickener(s), expressed as solids, more particularly ranges from 0.1% to 40%> by weight, preferably from 0.1% to 20% by weight and even more preferentially from 0.1% to 10% by weight relative to the total weight of the oil(s) into which they are incorporated.

Organopolysiloxane elastomer

The organopolysiloxane elastomer that may be used as polymeric thickener also has the advantage of giving the composition according to the invention good application properties. It affords a very soft feel and a matt effect after application, which is advantageous especially for application to the skin, in particular for foundation compositions. It may also allow efficient filling of the hollows present on keratin materials.

The term "organopolysiloxane elastomer" or "silicone elastomer" means a supple, deformable organopolysiloxane with viscoelastic properties and especially with the consistency of a sponge or a supple sphere. Its modulus of elasticity is such that this material withstands deformation and has limited stretchability and contractability. This material is capable of regaining its original shape after stretching.

It is more particularly a crosslinked organopolysiloxane elastomer.

Thus, the organopolysiloxane elastomer may be obtained by crosslinking addition reaction of diorganopolysiloxane containing at least one hydrogen bonded to silicon and of diorganopolysiloxane containing ethylenically unsaturated groups bonded to silicon, especially in the presence of a platinum catalyst; or by dehydrogenation crosslinking condensation reaction between a diorganopolysiloxane containing hydroxyl end groups and a diorganopolysiloxane containing at least one hydrogen bonded to silicon, especially in the presence of an organotin; or by crosslinking condensation reaction of a diorganopolysiloxane containing hydroxyl end groups and of a hydrolysable organopolysilane; or by thermal crosslinking of organopolysiloxane, especially in the presence of an organoperoxide catalyst; or by crosslinking of organopolysiloxane via high- energy radiation such as gamma rays, ultraviolet rays or an electron beam.

Preferably, the organopolysiloxane elastomer is obtained by crosslinking addition reaction (A) of diorganopolysiloxane containing at least two hydrogens each bonded to a silicon, and (B) of diorganopolysiloxane containing at least two ethylenically unsaturated groups bonded to silicon, especially in the presence (C) of a platinum catalyst, as described, for instance, in patent application EP-A-295 886.

In particular, the organopolysiloxane elastomer may be obtained by reaction of dimethylpolysiloxane bearing dimethylvinylsiloxy end groups and of methylhydrogenopolysiloxane bearing trimethylsiloxy end groups, in the presence of a platinum catalyst.

Compound (A) is the base reagent for the formation of organopolysiloxane elastomer, and the crosslinking is performed by addition reaction of compound (A) with compound (B) in the presence of the catalyst (C). Compound (A) is in particular an organopolysiloxane containing at least two hydrogen atoms bonded to different silicon atoms in each molecule.

Compound (A) may have any molecular structure, in particular a linear-chain or branched-chain structure or a cyclic structure.

Compound (A) may have a viscosity at 25°C ranging from 1 to 50 000 centistokes, especially so as to be readily miscible with compound (B).

The organic groups bonded to the silicon atoms of compound (A) may be alkyl groups such as methyl, ethyl, propyl, butyl, octyl; substituted alkyl groups such as 2- phenylethyl, 2-phenylpropyl or 3,3,3-trifluoropropyl; aryl groups such as phenyl, tolyl, xylyl; substituted aryl groups such as phenylethyl; and substituted monovalent hydrocarbon-based groups such as an epoxy group, a carboxylate ester group or a mercapto group.

Compound (A) may thus be chosen from trimethylsiloxy-terminated methylhydrogenopolysiloxanes, trimethylsiloxy-terminated dimethylsiloxane/methyl- hydrogenosiloxane copolymers, and dimethylsiloxane/methylhydrogenosiloxane cyclic copolymers.

Compound (B) is advantageously a diorganopolysiloxane containing at least two lower alkenyl groups (for example C2-C4); the lower alkenyl group may be chosen from vinyl, allyl and propenyl groups. These lower alkenyl groups may be located at any position on the organopolysiloxane molecule but are preferably located at the ends of the organopolysiloxane molecule. The organopolysiloxane (B) may have a branched-chain, linear-chain, cyclic or network structure but the linear-chain structure is preferred. Compound (B) may have a viscosity ranging from the liquid state to the gum state. Preferably, compound (B) has a viscosity of at least 100 centistokes at 25°C.

Besides the abovementioned alkenyl groups, the other organic groups bonded to the silicon atoms in compound (B) may be alkyl groups such as methyl, ethyl, propyl, butyl or octyl; substituted alkyl groups such as 2-phenylethyl, 2-phenylpropyl or 3,3,3- trifluoropropyl; aryl groups such as phenyl, tolyl or xylyl; substituted aryl groups such as phenylethyl; and substituted monovalent hydrocarbon-based groups such as an epoxy group, a carboxylate ester group or a mercapto group.

The organopolysiloxanes (B) may be chosen from methylvinylpolysiloxanes, methylvinylsiloxane-dimethylsiloxane copolymers, dimethylpolysiloxanes bearing dimethylvinylsiloxy end groups, dimethylsiloxane-methylphenylsiloxane copolymers bearing dimethylvinylsiloxy end groups, dimethylsiloxane-diphenylsiloxane- methylvinylsiloxane copolymers bearing dimethylvinylsiloxy end groups, dimethylsiloxane-methylvinylsiloxane copolymers bearing trimethylsiloxy end groups, dimethylsiloxane-methylphenylsiloxane-methylvinylsiloxane copolymers bearing trimethylsiloxy end groups, methyl(3,3,3-trifluoropropyl)polysiloxanes bearing dimethylvinylsiloxy end groups, and dimethylsiloxane-methyl(3,3,3- trifluoropropyl)siloxane copolymers bearing dimethylvinylsiloxy end groups.

In particular, the elastomeric organopolysiloxane may be obtained via reaction of dimethylvinylsiloxy-terminated dimethylpolysiloxane and of trimethylsiloxy-terminated methylhydrogenopolysiloxane, in the presence of a platinum catalyst.

Advantageously, the sum of the number of ethylenic groups per molecule of compound (B) and of the number of hydrogen atoms bonded to silicon atoms per molecule of compound (A) is at least 5.

It is advantageous for compound (A) to be added in an amount such that the molecular ratio of the total amount of hydrogen atoms bonded to silicon atoms in compound (A) to the total amount of all the ethylenically unsaturated groups in compound (B) is within the range from 1.5/1 to 20/1.

Compound (C) is the catalyst for the crosslinking reaction, and is especially chloroplatinic acid, chloroplatinic acid-olefin complexes, chloroplatinic acid- alkenylsiloxane complexes, chloroplatinic acid-diketone complexes, platinum black and platinum on a support.

Catalyst (C) is preferably added in an amount of from 0.1 to 1000 parts by weight and better still from 1 to 100 parts by weight, as clean platinum metal, per 1000 parts by weight of the total amount of compounds (A) and (B).

The elastomer is advantageously a non-emulsifying elastomer.

The term "non-emulsifying" defines organopolysiloxane elastomers not containing any hydrophilic chains, and in particular not containing any polyoxyalkylene units (especially polyoxy ethylene or polyoxypropylene) or any polyglyceryl units. Thus, according to a particular mode of the invention, the O/O emulsion comprises an organopolysiloxane elastomer free of polyoxyalkylene units and of polyglyceryl units. In particular, the silicone elastomer used in the present invention is chosen from Dimethicone Crosspolymer (INCI name), Vinyl Dimethicone Crosspolymer (INCI name), Dimethicone /Vinyl Dimethicone Crosspolymer (INCI name), Dimethicone Crosspolymer-3 (INCI name).

The organopolysiloxane elastomer particles may be conveyed in the form of a gel formed from an elastomeric organopolysiloxane included in at least one hydrocarbon- based oil and/or one silicone oil. In these gels, the organopolysiloxane particles are often non-spherical particles.

Non-emulsifying elastomers are described especially in patents EP 242 219, EP 285 886 and EP 765 656 and in patent application JP-A-61-194009, the content of which is incorporated by way of reference.

The silicone elastomer is generally in the form of a gel, a paste or a powder, but advantageously in the form of a gel in which the silicone elastomer is dispersed in a linear silicone oil (dimethicone) or cyclic silicone oil (e.g.: cyclopentasiloxane), advantageously in a linear silicone oil.

Non-emulsifying elastomers that may be used more particularly include those sold under the names KSG-6, KSG-15, KSG-16, KSG-18, KSG-41, KSG-42, KSG-43 and KSG-44 by the company Shin-Etsu, DC9040 and DC9041 by the company Dow Corning, and SFE 839 by the company General Electric.

According to a particular mode, use is made of a gel of silicone elastomer dispersed in a silicone oil chosen from a non-exhaustive list comprising cyclopentadimethylsiloxane, dimethicones, dimethylsiloxanes, methyl trimethicone, phenyl methicone, phenyl dimethicone, phenyl trimethicone and cyclomethicone, preferably a linear silicone oil chosen from polydimethylsiloxanes (PDMSs) or dimethicones with a viscosity at 25°C ranging from 1 to 500 cSt, optionally modified with optionally fluorinated aliphatic groups, or with functional groups such as hydroxyl, thiol and/or amine groups.

Mention may be made especially of the compounds having the following INCI names:

- dimethicone/vinyl dimethicone crosspolymer, such as USG-105 and USG-

107A from the company Shin-Etsu; DC9506 and DC9701 from the company Dow Corning; - dimethicone/vinyl dimethicone crosspolymer (and) dimethicone, such as KSG-6 and KSG-16 from the company Shin-Etsu;

- dimethicone/vinyl dimethicone crosspolymer (and) cyclopentasiloxane, such as KSG-15;

- cyclopentasiloxane (and) dimethicone crosspolymer, such as DC9040,

DC9045 and DC5930 from the company Dow Corning;

- dimethicone (and) dimethicone crosspolymer, such as DC9041 from the company Dow Corning;

- C4-24 alkyl dimethicone/di vinyl dimethicone crosspolymer, such as NuLastic Silk MA from the company Alzo.

As examples of silicone elastomers dispersed in a linear silicone oil that may advantageously be used according to the invention, mention may especially be made of the following references:

- dimethicone/vinyl dimethicone crosspolymer (and) dimethicone, such as

KSG-6 and KSG-16 from the company Shin-Etsu;

- dimethicone (and) dimethicone crosspolymer, such as DC9041 from the company Dow Corning. According to a particularly preferred embodiment, the O/O emulsion according to the invention comprises at least one crosslinked silicone elastomer having the INCI name "dimethicone (and) dimethicone crosspolymer", preferably with a dimethicone having a viscosity ranging from 1 to 100 cSt, in particular from 1 to 10 cSt at 25°C, such as the mixture of polydimethylsiloxane crosslinked with hexadiene/polydimethylsiloxane (5 cSt) sold under the name DC 9041 by the company Dow Corning.

The organopolysiloxane elastomer particles may also be used in powder form: mention may be made of the powders sold under the names Dow Corning 9505 Powder and Dow Corning 9506 Powder by the company Dow Corning, these powders having the INCI name: dimethicone/vinyl dimethicone crosspolymer.

The organopolysiloxane powder may also be coated with silsesquioxane resin, as described, for example, in patent US 5 538 793. Such elastomeric powders are sold under the names KSP-lOO, KSP-101, KSP-102, KSP-103, KSP-104 and KSP-105 by the company Shin-Etsu, and have the INCI name: vinyl dimethicone/methicone silsesquioxane crosspolymer. Semi- crystalline polymers

The O/O emulsion according to the invention may comprise at least one semi- crystalline polymer. Preferably, the semi-crystalline polymer has an organic structure, and a melting point of greater than or equal to 30°C.

For the purposes of the invention, the term "semi-crystalline polymer" means polymers comprising a crystallizable portion and an amorphous portion and having a first- order reversible change of phase temperature, in particular of melting point (solid-liquid transition). The crystallizable part is either a side chain (or pendent chain) or a block in the backbone.

When the crystallizable portion of the semi-crystalline polymer is a block of the polymer backbone, this crystallizable block has a chemical nature different than that of the amorphous blocks; in this case, the semi-crystalline polymer is a block copolymer, for example of the diblock, triblock or multiblock type. When the crystallizable portion is a chain that is pendent on the backbone, the semicrystalline polymer may be a homopolymer or a copolymer.

The melting point of the semicrystalline polymer is preferably less than 150°C.

The melting point of the semi-crystalline polymer is preferably greater than or equal to 30°C and less than 100°C. More preferably, the melting point of the semi- crystalline polymer is preferably greater than or equal to 30°C and less than 70°C.

The semi-crystalline polymer(s) according to the invention are solid at room temperature (25°C) and atmospheric pressure (760 mmHg), with a melting point of greater than or equal to 30°C. The melting point values correspond to the melting point measured using a differential scanning calorimeter (DSC), such as the calorimeter sold under the name DSC 30 by the company Mettler, with a temperature rise of 5°C or 10°C per minute. (The melting point under consideration is the point corresponding to the temperature of the most endothermic peak of the thermogram). The semi-crystalline polymer(s) according to the invention preferably have a melting point that is higher than the temperature of the keratin support intended to receive said composition, in particular the skin or the lips.

For the purposes of the invention, the term "crystallizable chain or block" means a chain or block which, if it were alone, would change from the amorphous state to the crystalline state reversibly, depending on whether the temperature is above or below the melting point. For the purposes of the invention, a chain is a group of atoms, which are pendent or lateral relative to the polymer backbone. A "block" is a group of atoms belonging to the backbone, this group constituting one of the repeating units of the polymer.

Preferably, the polymer backbone of the semi-crystalline polymers is soluble in the oily phase at a temperature above their melting point.

Preferably, the crystallizable blocks or chains of the semi-crystalline polymers represent at least 30% of the total weight of each polymer and better still at least 40%. The semi-crystalline polymers containing crystallizable side chains are homopolymers or copolymers. The semi-crystalline polymers of the invention bearing crystallizable blocks are block or multiblock copolymers. They may be obtained by polymerizing a monomer bearing reactive (or ethylenic) double bonds or by polycondensation. When the polymers of the invention are polymers bearing crystallizable side chains, these side chains are advantageously in random or statistical form.

Preferably, the semicrystalline polymers of the invention are of synthetic origin.

According to a preferred embodiment, the semi-crystalline polymer is chosen from:

- homopolymers and copolymers comprising units resulting from the polymerization of one or more monomers bearing crystallizable hydrophobic side chain(s),

- polymers bearing in the backbone at least one crystallizable block,

- poly condensates of aliphatic or aromatic or aliphatic/aromatic polyester type,

- copolymers of ethylene and propylene prepared via metallocene catalysis, and - acrylate/silicone copolymers.

The semi-crystalline polymers that may be used in the invention may be chosen in particular from: - block copolymers of polyolefms of controlled crystallization, the monomers of which are described in EP-A-0 951 897,

- poly condensates, especially of aliphatic or aromatic or aliphatic/aromatic polyester type,

- copolymers of ethylene and propylene prepared via metallocene catalysis,

- homopolymers or copolymers bearing at least one crystallizable side chain and homopolymers or copolymers bearing in the backbone at least one crystallizable block, such as those described in document US-A-5 156 911, such as the (Cio-C3o)alkyl polyacrylates corresponding to the Intelimer^® products from the company Landec described in the brochure Intelimer^® Polymers, Landec IP22 (Rev. 4-97), for example the product Intelimer^® IP A 13-1 from the company Landec, which is a polystearyl acrylate with a molecular weight of about 145 000 and a melting point of 49°C,

- homopolymers or copolymers bearing at least one crystallizable side chain, in particular bearing fluoro group(s), as described in document WO-A-01/19333,

- acrylate/silicone copolymers, such as copolymers of acrylic acid and of stearyl acrylate bearing polydimethylsiloxane grafts, copolymers of stearyl methacrylate bearing polydimethylsiloxane grafts, copolymers of acrylic acid and of stearyl methacrylate bearing polydimethylsiloxane grafts, copolymers of methyl methacrylate, butyl methacrylate, 2-ethylhexyl acrylate and stearyl methacrylate bearing polydimethylsiloxane grafts. Mention may be made in particular of the copolymers sold by the company Shin-Etsu under the names KP-561 (CTFA name: acrylates/dimethicone),

- and mixtures thereof.

Hydrocarbon-based polyamide

For the purposes of the invention, the term "polymer" means a compound containing at least two repeating units, preferably at least three repeating units and better still ten repeating units.

For the purposes of the invention, the term "polyamide" means a compound containing at least two, preferably at least three and better still ten amide repeating units.

The term "hydrocarbon-based polyamide" means a polyamide formed essentially of, indeed even constituted by, carbon and hydrogen atoms, and optionally of oxygen or nitrogen atoms, and not comprising any silicon or fluorine atoms. It may contain alcohol, ester, ether, carboxylic acid, amine and/or amide groups.

For the purposes of the invention, the term "functionalized chain" means an alkyl chain comprising one or more functional groups or reagents chosen especially from hydroxyl, ether, ester, oxyalkylene and polyoxyalkylene groups.

Advantageously, this polyamide of the emulsion according to the invention has a weight-average molecular mass of less than 100 000 g/mol, especially ranging from 1000 to 100 000 g/mol, in particular ranging from 1000 to 50 000 g/mol, more particularly ranging from 1000 to 30 000 g/mol, preferably from 2000 to 20 000 g/mol and better still from 2000 to 10 000 g/mol.

This polyamide is insoluble in water, especially at 25°C.

According to a first embodiment of the invention, the polyamide is a compound (i), namely a hydrocarbon-based polyamide, in particular a non-silicone polyamide, of formula (la) below:

in which n denotes a whole number of amide units such that the number of ester groups represents from 10% to 50% of the total number of ester and amide groups; Ri is, independently in each case, an alkyl or alkenyl group containing at least 4 carbon atoms and in particular from 4 to 24 carbon atoms; R₂ represents, independently in each case, a C₄ to C₄₂ hydrocarbon-based group, on condition that 50%> of the groups R₂ represent a C30 to C₄₂ hydrocarbon-based group; R3 represents, independently in each case, an organic group containing at least 2 carbon atoms, hydrogen atoms and optionally one or more oxygen or nitrogen atoms; and R₄ represents, independently in each case, a hydrogen atom, a Ci to Cio alkyl group or a direct bond to R3 or to another R₄, such that the nitrogen atom to which R3 and R₄ are both attached forms part of a heterocyclic structure defined by R4NR3, with at least 50%> of the groups R₄ representing a hydrogen atom.

In the particular case of formula (la), the optionally functionalized terminal fatty chains are terminal chains linked to the last heteroatom, in this case nitrogen, of the polyamide backbone. In particular, the ester groups of formula (I), which form part of the terminal and/or pendent fatty chains, represent from 15% to 40% of the total number of ester and amide groups and better still from 20%> to 35%. Furthermore, n advantageously represents an integer ranging from 1 to 5 and better still greater than 2. Preferably, Ri is a C₁₂ to C22 and preferably C₁₆ to C22 alkyl group. Advantageously, R2 may be a C10 to C42 hydrocarbon-based, preferably alkylene, group. Preferably, R2 is a divalent radical derived from acid dimer. Preferably, at least 50% and better still at least 75% of the groups R2 are groups containing from 30 to 42 carbon atoms. The other groups R2 are C₄ to C19 and even C₄ to C12 hydrogen-containing groups. Preferably, R3 represents a C2 to C36 hydrocarbon- based group or a polyoxyalkylene group and R₄ represents a hydrogen atom. Preferably, R3 represents a C2 to C12, preferably C₂, hydrocarbon-based group.

The hydrocarbon-based groups may be linear, cyclic or branched, and saturated or unsaturated groups. Moreover, the alkyl and alkylene groups may be linear or branched, and saturated or unsaturated groups.

Preferably, the hydrocarbon-based polyamide of formula (la) is such that n is an integer ranging from 1 to 5, preferably greater than 2, Ri is a C12 to C22 and preferably Ci6 to C22 alkyl group, R2 is a C10 to C42 hydrocarbon-based group, preferably a divalent radical derived from acid dimer, R3 represents a C2 to C12, preferably C₂, hydrocarbon- based group, and R₄ represents a hydrogen atom.

In general, the polyamides of formula (la) are in the form of mixtures of polyamides, these mixtures also possibly containing a synthetic product corresponding to a compound of formula (la) in which n is 0, i.e. a diester.

As examples of hydrocarbon-based polyamides of formula (la) that may be used in the emulsions according to the invention, mention may be made of the commercial products sold by the company Arizona Chemical under the names Uniclear 80 and Uniclear 100, the INCI name of which is ethylenediamine/stearyl dimer dilinoleate copolymer, or Uniclear 80 V, Uniclear 100 V and Uniclear 100 VG, the INCI name of which is ethylenediamine/stearyl dimer tallate copolymer. They are sold, respectively, in the form of a gel at 80% active material in a mineral oil and at 100% active material. They have a softening point of from 88 to 94°C. These commercial products are a mixture of copolymers of a C36 diacid coupled with ethylenediamine, having a weight-average molecular mass of about 6000 g/mol. The terminal ester groups result from the esterification of the remaining acid end groups with cetyl alcohol, stearyl alcohol or mixtures thereof (also known as cetylstearyl alcohol).

Hydrocarbon-based polyamides that may also be mentioned include polyamide resins resulting from the condensation of an aliphatic dicarboxylic acid and a diamine, including compounds containing more than two carbonyl groups and two amine groups, the carbonyl and amine groups of adjacent individual units being condensed in the form of an amide bond. These polyamide resins are especially the products sold under the brand name Versamid® by the companies General Mills, Inc. and Henkel Corp., (Versamid 930, 744 or 1655) or by the company Olin Mathieson Chemical Corp., under the brand name Onamid®, especially Onamid S or C. These resins have a weight-average molecular mass ranging from 6000 to 9000 g/mol. For further information regarding these polyamides, reference may be made to documents US-A-3 645 705 and US-A-3 148 125. Use is made more especially of Versamid® 930 or 744.

It is also possible to use the polyamides sold by the company Arizona Chemical under the references Uni-Rez (2658, 2931 , 2970, 2621, 2613, 2624, 2665, 1554, 2623 and 2662) and the product sold under the reference Macromelt 6212 by the company Henkel. For further information regarding these polyamides, reference may be made to document US-A-5 500 209.

It is also possible to use polyamide resins, such as those disclosed in patents US-A-5 783 657 and US-A-5 998 570.

The polyamide advantageously has a softening point of greater than 65°C, which may be up to 190°C. It preferably has a softening point ranging from 70°C to 130°C and better still from 80°C to 105°C.

Particularly preferably, the polyamide used is Uniclear 100 VG, the INCI name of which is ethylenediamine/stearyl dimer tallate copolymer.

Silicone polyamide

The silicone polyamides are preferably solid at room temperature (25°C) and atmospheric pressure (760 mrnHg).

The silicone polyamides may be more particularly polymers comprising at least one unit corresponding to the general formula I:

1) in which: G' represents C(O) when G represents -C(0)-NH-Y-NH-, and G' represents -NH- when G represents -NH-C(0)-Y-C(0)-,

2) R⁴, R⁵, R⁶ and R⁷, which may be identical or different, represent a group chosen from:

- linear, branched or cyclic, saturated or unsaturated, Ci to C₄o hydrocarbon- based groups, possibly containing in their chain one or more oxygen, sulfur and/or nitrogen atoms, and which may be partially or totally substituted with fluorine atoms,

- C₆ to Cio aryl groups, optionally substituted with one or more Ci to C₄ alkyl groups,

- polyorganosiloxane chains possibly containing one or more oxygen, sulfur and/or nitrogen atoms,

3) the groups X, which may be identical or different, represent a linear or branched Ci to C30 alkylenediyl group, possibly containing in its chain one or more oxygen and/or nitrogen atoms,

4) Y is a saturated or unsaturated Ci to C50 linear or branched alkylene, arylene, cycloalkylene, alkylarylene or arylalkylene divalent group, which may comprise one or more oxygen, sulfur and/or nitrogen atoms, and/or may bear as substituent one of the following atoms or groups of atoms: fluorine, hydroxyl, C3 to Cs cycloalkyl, Ci to C₄o alkyl, C5 to Cio aryl, phenyl optionally substituted with one to three Ci to C3 alkyl, Ci to C3 hydroxyalkyl and Ci to C₆ aminoalkyl groups, or

Y represents a group corresponding to the formula:

R° in which

- T represents a linear or branched, saturated or unsaturated, C3 to C₂₄ trivalent tetravalent hydrocarbon-based group optionally substituted with a polyorganosiloxane chain, and possibly containing one or more atoms chosen from O, N and S, or T represents a trivalent atom chosen from N, P and Al, and

- R⁸ represents a linear or branched C1-C50 alkyl group or a polyorganosiloxane chain, possibly comprising one or more ester, amide, urethane, thiocarbamate, urea, thiourea and/or sulfonamide groups, which may possibly be linked to another chain of the polymer;

- n is an integer ranging from 2 to 500 and preferably from 2 to 200, and m is an integer ranging from 1 to 1000, preferably from 1 to 700 and better still from 6 to 200.

According to one embodiment of the invention, 80% of the groups R⁴, R⁵, R⁶ and R⁷ of the polymer are preferably chosen from methyl, ethyl, phenyl and 3,3,3- trifluoropropyl groups. According to another embodiment, 80% of the groups R⁴, R⁵, R⁶ and R⁷ of the polymer are methyl groups.

According to the invention, Y may represent various divalent groups, furthermore optionally comprising one or two free valencies to establish bonds with other units of the polymer or copolymer. Preferably, Y represents a group chosen from:

a) linear Ci to C20 and preferably Ci to C10 alkylene groups,

b) C30 to C50 branched alkylene groups possibly comprising rings and unconjugated unsaturations,

c) C5-C6 cycloalkylene groups,

d) phenylene groups optionally substituted with one or more Ci to C40 alkyl groups,

e) Ci to C20 alkylene groups comprising from 1 to 5 amide groups, f) Ci to C20 alkylene groups comprising one or more substituents chosen from hydroxyl, C3 to Cs cycloalkane, Ci to C3 hydroxyalkyl and Ci to C₆ aminoalkyl groups,

g) polyorganosiloxane chains of formula:

or

m in which R⁴, R⁵, R⁶, R⁷, T and m are as defined above.

According to the invention, the silicone polymer may be a homopolymer, i.e. a polymer comprising several identical units, of formula (I).

According to the invention, it is also possible to use a polymer consisting of a copolymer comprising several different units of formula (I), i.e. a polymer in which at least one of the groups R⁴, R⁵, R⁶, R⁷, X, G, G', Y, m and n is different in one of the units.

According to one variant of the invention, it is also possible to use a silicone polyamide furthermore comprising at least one hydrocarbon-based unit comprising two groups capable of establishing hydrogen interactions, chosen from ester, amide, sulfonamide, carbamate, thiocarbamate, urea, urethane, thiourea, oxamido, guanidino and biguanidino groups, and combinations thereof.

These copolymers may be block polymers or grafted polymers.

In formula (I), the alkylene group representing X or Y may optionally contain in its alkylene part at least one of the following components:

1) one to five amide, urea, urethane or carbamate groups,

2) a C₅ or C₆ cycloalkyl group, and

3) a phenylene group optionally substituted with 1 to 3 identical or different Ci to C₃ alkyl groups.

In formula (I), the alkylene groups may also be substituted with at least one component chosen from the group formed by:

- a hydroxy 1 group,

- a C₃ to C8 cycloalkyl group,

- one to three Ci to C₄o alkyl groups,

- a phenyl group optionally substituted with one to three Ci to C₃ alkyl groups,

- a Ci to C₃ hydroxy alkyl group, and

- a Ci to C₆ aminoalkyl group. In this formula (I), Y may also represent:

ΪΓ T in which R represents a polyorganosiloxane chain and T represents a group of formula:

R

.(CH₂)_a C (CH₂)_b or - (CH₂)_a _N . (CH₂)_b _

(CH₂)_C (CH₂)_C

in which a, b and c are, independently, integers ranging from 1 to 10, and R¹³ is a hydrogen atom or a group such as those defined for R⁴, R⁵, R⁶ and R⁷.

In formula (I), R⁴, R⁵, R⁶ and R⁷ preferably represent, independently, a linear or branched Ci to C₄o alkyl group, preferably a CH₃, C2H5, n-C₃H₇ or isopropyl group, a polyorganosiloxane chain or a phenyl group optionally substituted with one to three methyl or ethyl groups.

According to an advantageous embodiment of the invention, the silicone polyamide com rises at least one unit of formula (III) or (IV):

in which R , R , R , R , X, Y, m and n are as defined above. In these silicone polyamides of formula (III) or (IV), m ranges from 1 to 700, in particular from 15 to 500 and especially from 50 to 200, and n ranges in particular from 1 to 500, preferably from 1 to 100 and better still from 4 to 25,

- X is preferably a linear or branched alkylene chain containing from 1 to 30 carbon atoms, in particular 1 to 20 carbon atoms, especially from 5 to 15 carbon atoms and more particularly 10 carbon atoms, and

- Y is preferably an alkylene chain that is linear or branched, or which may comprise rings and/or unsaturations, containing from 1 to 40 carbon atoms, in particular 1 to 20 carbon atoms and better still from 2 to 6 carbon atoms, in particular 6 carbon atoms.

In formulae (III) and (IV), the alkylene group representing X or Y may optionally contain in its alkylene portion at least one of the following components:

• one to five amide, urea, urethane or carbamate groups,

· a C₅ or C₆ cycloalkyl group, and

• a phenylene group optionally substituted with 1 to 3 identical or different Ci to C₃ alkyl groups.

In formulae (III) and (IV), the alkylene groups may also be substituted with at least one component chosen from the group consisting of:

- a hydroxyl group,

- a C₃ to C8 cycloalkyl group,

- one to three Ci to C₄o alkyl groups,

- a Ci to C₃ hydroxy alkyl group, and

- a Ci to C₆ aminoalkyl group.

In these formulae (III) and IV), Y may also represent:

in which R represents a polyorganosiloxane chain and T represents a group of formula: 13

R

_(CH₂)_a C (CH₂)_b or (_CH₂)_a N (CH₂)_b _-

(CH₂)_C (CH₂)_C

In formulae (III) and (IV), R⁴, R⁵, R⁶ and R⁷ preferably represent, independently, a linear or branched Ci to C₄o alkyl group, preferably a CH₃, C2H5, n-C₃H7 or isopropyl group, a polyorganosiloxane chain or a phenyl group optionally substituted with one to three methyl or ethyl groups.

As has been seen previously, the polymer may comprise identical or different units of formula (III) or (IV).

Thus, the polymer may be a polyamide containing several units of formula (III) or (IV) of different lengths, i.e. a polyamide corresponding to formula (V):

in which X, Y, n and R⁴ to R⁷ have the meanings given above, mi and m₂, which are different, are chosen in the range from 1 to 1000, and p is an integer ranging from 2 to 300.

In this formula, the units may be structured to form either a block copolymer, or a random copolymer or an alternating copolymer. In this copolymer, the units may be not only of different lengths, but also of different chemical structures, for example containing different groups Y. In this case, the polymer may correspond to formula VI:

R⁴ R R⁴ R

I I

C(O)— x- -SiO- -Si- -C(O)- NH— Y- NH- C(O)— x- -SiO -Si- -C(O)- NH— Y- ^■ NH4

R« R«

in which R⁴ to R⁷, X, Y, mi, m₂, n and p have the meanings given above and Y¹ is different from Y but chosen from the groups defined for Y. As previously, the various units may be structured to form either a block copolymer, or a random copolymer or an alternating copolymer. In this first embodiment of the invention, the silicone polyamide may also be formed from a grafted copolymer. Thus, the polyamide containing silicone units may be grafted and optionally crosslinked with silicone chains containing amide groups. Such polymers may be synthesized with trifunctional amines.

In this case, the polymer may comprise at least one unit of formula (VII):

in which X¹ and X², which are identical or different, have the meaning given for X in formula (I), n is as defined in formula (I), Y and T are as defined in formula (I), R¹⁴ to R²¹ are groups chosen from the same group as R⁴ to R⁷, mi and m₂ are numbers in the range from 1 to 1000, and p is an integer ranging from 2 to 500.

In formula (VII), it is preferred that:

- p be in the range from 1 to 25 and better still from 1 to 7,

- R¹⁴ to R²¹ be methyl groups,

- T correspond to one of the following formulae:

,23 . Al in which R is a hydrogen atom or a group chosen from the groups defined for R⁴ to R⁷, and R²³, R²⁴ and R²⁵ are, independently, linear or branched alkylene groups, and more preferably correspond to the formula:

23

R 24

- . R

in particular with R , R and R representing -CH2-CH2-,

- mi and m2 be in the range from 15 to 500 and better still from 15 to 45,

- Xi and X2 represent -(CH₂)₁₀-, and

- Y represent -CH2-.

These polyamides containing a grafted silicone unit of formula (VII) may be copolymerized with polyamide-silicones of formula (II) to form block copolymers, alternating copolymers or random copolymers. The weight percentage of grafted silicone units (VII) in the copolymer may range from 0.5% to 30% by weight.

As has been seen previously, the siloxane units may be in the main chain or backbone of the polymer, but they may also be present in grafted or pendent chains. In the main chain, the siloxane units may be in the form of segments as described above. In the pendent or grafted chains, the siloxane units may appear individually or in segments.

According to a preferred embodiment variant of the invention, use may be made of a copolymer comprising units of formula (III) or (IV) and hydrocarbon-based polyamide units. In this case, the polyamide-silicone units may be located at the ends of the hydrocarbon-based polyamide.

According to a preferred embodiment, the silicone polyamide comprises units of formula III.

Preferably, according to this embodiment, the groups R⁴, R⁵, R⁶ and R⁷ represent methyl groups, one from among X and Y represents an alkylene group containing 6 carbon atoms and the other represents an alkylene group containing 11 carbon atoms. n is an integer ranging from 2 to 500; n represents the degree of polymerization DP of the polymer.

Examples of such silicone polyamides that may be mentioned include the compounds sold by the company Dow Corning under the names DC 2-8179 (DP 100) and DC 2-8178 (DP 15), the INCI name of which is Nylon-61 1/dimethicone copolymer, i.e. Nylon-61 1/dimethicone copolymers.

Advantageously, the emulsion used according to the invention comprises at least one polydimethylsiloxane block polymer of general formula (I) with an m value of about 100.

The value "m" corresponds to the degree of polymerization of the silicone portion of the polymer.

More preferably, the emulsion according to the invention comprises at least one polymer comprising at least one unit of formula (III) in which m ranges from 50 to 200, in particular from 75 to 150 and is preferably about 100.

More preferably, R⁴, R⁵, R⁶ and R⁷ independently represent a linear or branched Ci to C₄o alkyl group, preferably a group CH₃, C2H5, n-C₃H₇ or an isopropyl group in formula (III).

As examples of silicone polymers that may be used, mention may be made of one of the silicone polyamides obtained in accordance with Examples 1 to 3 of document US-A-5 981 680.

According to a preferred mode, use is made of the polyamide silicone polymer sold by the company Dow Corning under the name DC 2-8179 (DP 100).

The silicone polymers and/or copolymers used in the emulsion of the invention advantageously have a temperature of transition from the solid state to the liquid state ranging from 45°C to 190°C. Preferably, they have a temperature of transition from the solid state to the liquid state ranging from 70 to 130°C and better still from 80°C to 105°C.

Dextrin esters The 0/0 emulsion according to the invention may comprise as polymeric thickener at least one dextrin ester.

In particular, the 0/0 emulsion preferably comprises at least one preferably C12-C24 and in particular C₁₄-C₁₈ fatty acid ester of dextrin, or mixtures thereof.

Preferably, the dextrin ester is an ester of dextrin and of a C₁₂-C₁₈ and in particular C₁₄-C₁₈ fatty acid.

Preferably, the dextrin ester is chosen from dextrin myristate and/or dextrin palmitate, and mixtures thereof.

According to a particular embodiment, the dextrin ester is dextrin myristate, such as the product sold especially under the name Rheopearl MKL-2 by the company Chiba Flour Milling.

According to a preferred embodiment, the dextrin ester is dextrin palmitate. This product may be chosen, for example, from those sold under the names Rheopearl TL^®, Rheopearl KL^® and Rheopearl^® KL2 by the company Chiba Flour Milling.

MINERAL THICKENERS

Among the mineral thickeners that are suitable for use in the present invention, mention may be made of modified clays, and silicas, alone or as a mixture. When the 0/0 emulsion comprises any, the content of mineral thickener is advantageously between 0.1% and 20%> and preferably from 0.1 % to 10% by weight relative to the total weight of the oil(s) into which they are incorporated.

Modified clays

The 0/0 emulsion according to the invention may comprise at least one lipophilic clay.

The clays may be natural or synthetic, and they are made lipophilic by treatment with an alkylammonium salt such as a C10 to C22 ammonium chloride, for example distearyldimethylammonium chloride.

They may be chosen from bentonites, in particular hectorites and montmorillonites, beidellites, saponites, nontronites, sepiolites, biotites, attapulgites and vermiculites. They are preferably chosen from hectorites.

Hectorites modified with a Cio to C22 ammonium chloride, such as hectorite modified with distearyldimethylammonium chloride, for instance the product sold under the name Bentone 38V^® by the company Elementis or bentone gel in isododecane sold under the name Bentone Gel ISD V^® (87% isododecane/ 10% disteardimonium hectorite/3% propylene carbonate) by the company Elementis, are preferably used as lipophilic clays.

Lipophilic clay may especially be present in a content ranging from 0.1% to 15% by weight, in particular from 0.5% to 10% and more particularly from 1% to 10% by weight relative to the total weight of the oil(s) into which they are incorporated.

Silicas

The O/O emulsion according to the invention may also comprise, as thickener, a fumed silica or silica aerogel particles. a) Fumed silica

Fumed silica which has undergone a hydrophobic surface treatment is most particularly suitable for use in the invention. This is because it is possible to chemically modify the surface of the silica, by chemical reaction generating a reduction in the number of silanol groups present at the surface of the silica. It is especially possible to substitute silanol groups with hydrophobic groups: a hydrophobic silica is then obtained.

The hydrophobic groups may be:

- trimethylsiloxyl groups, which are obtained especially by treating fumed silica in the presence of hexamethyldisilazane. Silicas thus treated are known as "Silica silylate" according to the CTFA (8th edition, 2000). They are sold, for example, under the references Aerosil R812^® by the company Degussa, and Cab-O-Sil TS-530^® by the company Cabot;

- dimethylsilyloxyl or polydimethylsiloxane groups, which are obtained in particular by treating fumed silica in the presence of polydimethylsiloxane or dimethyldichlorosilane. Silicas thus treated are known as "silica dimethyl silylate" according to the CTFA (8th edition, 2000). They are sold, for example, under the references Aerosil R972^® and Aerosil R974^® by the company Degussa, and Cab-O-Sil TS- 610^® and Cab-O-Sil TS-720^® by the company Cabot.

The fumed silicas may be present in an O/O emulsion according to the present invention in a content of between 0.1% and 40% by weight, more particularly between 1% and 15% by weight and even more particularly between 2% and 10% by weight relative to the total weight of the oil(s) into which they are incorporated. b) Hydrophobic silica aerogels

The O/O emulsion according to the invention may also comprise, as mineral thickener, at least silica aerogel particles.

Silica aerogels are porous materials obtained by replacing (by drying) the liquid component of a silica gel with air.

They are generally synthesized via a sol-gel process in a liquid medium and then dried, usually by extraction with a supercritical fluid, the one most commonly used being supercritical C0₂. This type of drying makes it possible to avoid shrinkage of the pores and of the material. The sol-gel process and the various drying processes are described in detail in Brinker CJ., and Scherer G.W., Sol-Gel Science: New York: Academic Press, 1990.

The hydrophobic silica aerogel particles used in the present invention have a specific surface area per unit mass (SM) ranging from 500 to 1500 m²/g, preferably from 600 to 1200 m²/g and better still from 600 to 800 m²/g, and a size expressed as the volume- mean diameter (D[0.5]) ranging from 1 to 1500 μιη, better still from 1 to 1000 μιη, preferably from 1 to 100 μιη, in particular from 1 to 30 μιη, more preferably from 5 to 25 μιη, better still from 5 to 20 μιη and even better still from 5 to 15 μιη.

According to one embodiment, the hydrophobic silica aerogel particles used in the present invention have a size expressed as volume-mean diameter (D[0.5]) ranging from 1 to 30 μιη, preferably from 5 to 25 μιη, better still from 5 to 20 μιη and even better still from 5 to 15 μιη.

The specific surface area per unit mass may be determined by the nitrogen absorption method, known as the BET (Brunauer-Emmett-Teller) method, described in The Journal of the American Chemical Society, vol. 60, page 309, February 1938 and corresponding to international standard ISO 5794/1 (appendix D). The BET specific surface area corresponds to the total specific surface area of the particles under consideration.

The sizes of the silica aerogel particles may be measured by static light scattering using a commercial particle size analyser such as the MasterSizer 2000 machine from Malvern. The data are processed on the basis of the Mie scattering theory. This theory, which is exact for isotropic particles, makes it possible to determine, in the case of non-spherical particles, an "effective" particle diameter. This theory is especially described in the publication by Van de Hulst, H.C., Light Scattering by Small Particles, Chapters 9 and 10, Wiley, New York, 1957.

According to an advantageous embodiment, the hydrophobic silica aerogel particles used in the present invention have a specific surface area per unit of mass (SM) ranging from 600 to 800 m²/g.

The silica aerogel particles used in the present invention may advantageously have a tapped density p ranging from 0.02 g/cm³ to 0.10 g/cm³, preferably from 0.03 g/cm³ to 0.08 g/cm³ and in particular ranging from 0.05 g/cm³ to 0.08 g/cm³.

In the context of the present invention, this density, known as the tapped density, may be assessed according to the following protocol:

40 g of powder are poured into a measuring cylinder; the measuring cylinder is then placed on a Stav 2003 machine from Stampf Volumeter; the measuring cylinder is then subjected to a series of 2500 tapping actions (this operation is repeated until the difference in volume between two consecutive tests is less than 2%); the final volume Vf of tapped powder is then measured directly on the measuring cylinder. The tapped density is determined by the ratio m/V f, in this instance 40/V f (Vf being expressed in cm³ and m in g).

According to a preferred embodiment, the hydrophobic silica aerogel particles used in the present invention have a specific surface area per unit of volume SV ranging from 5 to 60 m²/cm³, preferably from 10 to 50 m²/cm³ and better still from 15 to 40 m²/cm³.

The specific surface area per unit of volume is given by the relationship: Sv = SM X p; where p is the tapped density, expressed in g/cm³, and SM is the specific surface area per unit of mass, expressed in m²/g, as defined above. Preferably, the hydrophobic silica aerogel particles according to the invention have an oil-absorbing capacity, measured at the wet point, ranging from 5 to 18 ml/g, preferably from 6 to 15 ml/g and better still from 8 to 12 ml/g.

The absorbing capacity measured at the wet point, noted Wp, corresponds to the amount of oil that needs to be added to 100 g of particles in order to obtain a homogeneous paste.

It is measured according to what is known as the wet point method or the method for determining the oil uptake of a powder described in standard NF T 30-022. It corresponds to the amount of oil adsorbed onto the available surface of the powder and/or absorbed by the powder by measurement of the wet point, described below:

An amount m = 2 g of powder is placed on a glass plate, and the oil (isononyl isononanoate) is then added dropwise. After addition of 4 to 5 drops of oil to the powder, mixing is carried out using a spatula, and addition of oil is continued until conglomerates of oil and powder have formed. From this point, the oil is added at the rate of one drop at a time and the mixture is subsequently triturated with the spatula. The addition of oil is stopped when a firm, smooth paste is obtained. This paste must be able to be spread on the glass plate without cracking or forming lumps. The volume Vs (expressed in ml) of oil used is then noted.

The oil uptake corresponds to the ratio Vs/m.

The aerogels used according to the present invention are hydrophobic silica aerogels, preferably of silyl silica (INCI name: silica silylate).

The term "hydrophobic silica" means any silica whose surface is treated with silylating agents, for example halogenated silanes such as alkylchlorosilanes, siloxanes, in particular dimethylsiloxanes such as hexamethyldisiloxane, or silazanes, so as to functionalize the OH groups with silyl groups Si-Rn, for example trimethylsilyl groups.

As regards the preparation of hydrophobic silica aerogel particles that have been surface-modified by silylation, reference may be made to document US 7 470 725.

Use will preferably be made of hydrophobic silica aerogel particles surface- modified with trimethylsilyl groups, preferably of the INCI name Silica silylate.

As hydrophobic silica aerogels that may be used in the invention, examples that may be mentioned include the aerogel sold under the name VM-2260 or VM-2270 (INCI name: Silica silylate), by the company Dow Corning, the particles of which have a mean size of about 1000 microns and a specific surface area per unit of mass ranging from 600 to 800 m²/g.

Mention may also be made of the aerogels sold by the company Cabot under the references Aerogel TLD 201, Aerogel OGD 201 and Aerogel TLD 203, Enova^® Aerogel MT 1100 and Enova Aerogel MT 1200.

Use will preferably be made of the aerogel sold under the name VM-2270 (INCI name: Silica silylate) by the company Dow Corning, the particles of which have an average size ranging from 5-15 microns and a specific surface area per unit of mass ranging from 600 to 800 m²/g.

Preferably, the hydrophobic silica aerogel particles are present in the O/O emulsion according to the invention in a solids content ranging from 0.1% to 8% by weight, preferably from 0.2%> to 5% by weight and preferably from 0.2%> to 3% by weight relative to the total weight of the oil(s) into which they are incorporated.

According to a particularly preferred embodiment of the invention, the emulsion comprises at least one structuring agent chosen from waxes and pasty compounds, and mixtures thereof.

According to an advantageous embodiment of the invention, the O/O emulsion comprises:

- a first oily phase containing at least a first oil chosen from non- volatile phenyl or non-phenyl silicone oils,

- a second oily phase containing at least a second oil chosen from non-volatile hydrocarbon-based oils, in particular comprising at least two free hydroxyl groups, preferably at least three free hydroxyl groups, and

- a pasty compound chosen from lanolin and derivatives thereof, esters of glycerol oligomers, butters of plant origin, totally or partially hydrogenated plant oils, and hydrogenated castor oil esters, or mixtures thereof, and more particularly castor oil esters.

Processes

The present invention is also directed towards processes for preparing the emulsion according to the invention. The first oily phase is prepared in a first stage, and the second oily phase is prepared in a second stage.

Next, the process for preparing the emulsion may be continued, for example, according to the variants described below.

According to a first variant, the process for preparing the emulsion comprises the following steps, in this order:

- mixing of the first oily phase and of the second oily phase,

- emulsification of the mixture,

- introduction of the solid microparticles into the emulsion.

The first oily phase and the second oily phase are mixed together. The emulsification of these two oily phases leads to the creation of an interface, and more particularly a dispersion of one of the oily phases in the other oily phase.

In a second stage, the solid microparticles are added to the emulsion formed and the mixture is then agitated, either by means of a combination of shear forces or by ultrasonication.

According to a second variant, the process for preparing the emulsion is such that the solid microparticles are introduced into the first oily phase or into the second oily phase.

In this case, the process comprises the following steps, in this order:

- introduction of the solid microparticles into the first oily phase or into the second oily phase, respectively,

- introduction of the second oily phase or of the first oily phase, respectively, - emulsification of the mixture.

According to this second variant, the microparticles are first introduced into one of the two oily phases, and a combination of shear forces or ultrasonication is then applied, so as to obtain a homogeneous dispersion of said microparticles in said oily phase. The other oily phase is then added.

According to a third variant, the process for preparing the emulsion comprises the following steps, in this order: - simultaneous introduction of the solid microparticles, the first oily phase and the second oily phase,

- emulsification of the mixture.

According to this variant, the emulsion is obtained by mixing the solid microparticles and the two oily phases with vigorous stirring.

Irrespective of the process used, when one or both the oily phases comprise at least one structuring agent and/or at least one thickener, these agents are added to the oily phase into which each must be incorporated before the actual emulsification. The mixing preferably takes place at a temperature greater than or equal to the melting point of the structuring compound if it is present and the homogenization is advantageously performed at a temperature greater than or equal to this melting point.

Emulsification takes place by subjecting the mixture of the two oily phases and the solid microparticles to a combination of shear forces or ultrasonication, to obtain homogeneity thereof.

The term "homogeneity" of an emulsion is intended to denote an emulsion in which the drops of inner phases are uniformly dispersed in the continuous or outer oily phase.

The drops of dispersed phases in the emulsion may be very fine, in particular ranging from 0.1 to 10 μιη, or may be coarser, in particular ranging from 10 μιη to 1 cm.

A person skilled in the art may choose the conditions and the device that are the best suited for obtaining the combination of forces necessary for obtaining the targeted type of emulsion, especially for obtaining the targeted droplet size.

This combination of forces may be obtained by subjecting the first and second oily phases or the emulsion to manual shaking or to mechanical stirring with a blender such as a Moritz, Rayneri or Ultra-Turrax blender, or alternatively by ultrasonic homogenization.

The speed of blending or stirring for obtaining a homogeneous phase or emulsion may depend on various factors such as its composition or its volume. The various stirring parameters, especially the speed, may be determined by a person skilled in the art on the basis of his general knowledge and, where appropriate, by means of a few routine tests.

Usually, this operation is performed at a temperature between 10 and 50°C;

5 advantageously at a temperature between 15 and 30°C.

In the description and in the examples that follow, unless otherwise mentioned, the percentages are weight percentages and the ranges of values written in the form "between ... and ..." include the stated lower and upper limits.

The examples below are presented as nonlimiting illustrations of the field of the invention.

EXAMPLES

15 EXAMPLES OF FORMULATION VIA ULTRASONICATION

Sonicator XL machine from Misonix Incorporated for 1 minute to 1 minute 5 seconds with a power of 165 W.

Preparation protocol:

The emulsions are prepared by ultrasonication in two steps:

20 - "initiation" phase for 35 s to create interfaces,

- then "end of step" phase with addition of the particles for 30 s.

The power applied is that specified in the table below for each emulsion.

Example 1: Emulsions prepared using methylsilsesquioxane resin microbead particles

The microbeads used are sold under the name Tospearl AQ by the company Momentive. They have a mean diameter of 5 μιη.

Example Exampl Example Example Example Example Example

Starting materials

1.1 e l.2 1.3 1.4 1.5 1.6 1.7

PDMS oil 100 cSt (g/100 g)

47.5 47.5 47.5 (Belsil DM 100 sold by Wacker)

Castor oil (g/100 g) 47.5 47.5 47.5 47.5 (Codex sold by Interchimie)

Triethyl citrate (g/100 g)

47.5 47.5

(Citrofol AI sold by Jungbunzlauer)

Hydrogenated polyisobutene (g/lOOg)

47.5 47.5

(Parleam sold by NOF Corporation)

Isododecane (g/lOOg)

47.5

(sold by Ineos)

Polyphenyltrimethylsiloxydimethylsiloxane

47.5

(g/lOOg) (Belsil PDM 1000 sold by Wacker)

Pentaerythrityl tetraisostearate (g/lOOg)

47.5 (Crodamol PTIS-LQ-(MH) sold by Croda)

Solid particles (g/lOOg) 5 5 5 5 5 5 5

Total 100 100 100 100 100 100 100

Ultrasonication power (watts)/ 165W 165W 165W 165W 165W 165W 165W time (seconds) (35s+30s) (35s+30s) (35s+30s) (35s+30s) (35s+30s) (35s+30s) (35s+30s)

Example 2: Emulsions prepared using titanium oxide particles encapsulated in silica microspheres

5 The particles used are sold under the name Sunsil Tin 50 by the company

Sunjin Chemical. They have a mean diameter of between 2 and 7 μιη.

Example Example Example Example

Starting materials

2.1 2.2 2.3 2.4

PDMS oil 100 cSt (g/100 g)

47.5 47.5 47.5

(Belsil DM 100 sold by Wacker)

Castor oil (g/100 g)

47.5 47.5

(Codex sold by Interchimie)

Triethyl citrate (g/100 g)

47.5

( Citrofol AI sold by Jungbunzlauer)

Hydrogenated polyisobutene (g/lOOg) (Parleam

sold by NOF Corporation)

Pentaerythrityl tetraisostearate (g/lOOg)

47.5

(Crodamol PTIS-LQ-(MH) sold by Croda)

Polyphenyltrimethylsiloxydimethylsiloxane

47.5

(g/1 OOg) (Belsil PDM 1000 sold by Wacker) Trimethyl pentaphenyl trisiloxane

Solid particles (g/WOg) 5 5 5 5

Total 100 100 100 100

165W 165W 165W 165W

Ultrasonic ation power (watts)/time (seconds)

(35s+30s) (35s+30s) (35s+30s) (35s+30s)

Example 3: Emulsions prepared using crosslinked polydimethylsiloxane gum particles coated with silsesquioxane resin

5 The particles used are sold under the name KSP 100 by the company Shin-

Etsu. They have a mean diameter of 5 μιη.

Example Example Example Example Example Example

Starting materials

3.1 3.2 3.3 3.4 3.5 3.6

PDMS oil 100 cSt (g/100 g)

47.5 47.5 47.5

(Betel DM 100 sold by Wacker)

Castor oil (g/100 g)

47.5 47.5 47.5 (Codex sold by Interchimie)

Triethyl citrate (g/100 g)

47.5

( Citrofol AI sold by Jungbunzlauer)

Hydrogenated polyisobutene (g/lOOg)

47.5

(Parleam sold by NOF Corporation)

Pentaerythrityl tetraisostearate (g/lOOg)

47.5

(Crodamol PTIS-LQ-(MH) sold by Croda)

Polyphenyltrimethylsiloxydimethylsiloxane

47.5 (g/1 OOg) (Betel PDM 1000 sold by Wacker)

PDMS oil 350 cSt (g/lOOg) (Betel DM 350

47.5

sold by Wacker)

Trimethyl pentaphenyl trisiloxane (Dow

Corning PH-1555 HRI Cosmetic Fluid sold 47.5

by Dow Corning)

Solid microparticles 5 5 5 5 5 5

Total 100 100 100 100 100 100

165W 165W 165W 165W 165W 165W

Ultrasonic ation power (watts)/time (seconds)

(35s+30s) (35s+30s) (35s+30s) (35s+30s) (35s+30s) (35s+30s) Example 4: Emulsions prepared using a talc/ethylene-methacrylate copolymer mixture coated with isopropyl triisostearyl titanate

The particles used are sold under the name SPCAT-12 by the company Kobo. They have a mean diameter of 5 μιη.

EXAMPLE OF FORMULATION USING A RAYNERI BLENDER

Preparation protocol:

The emulsion is prepared in two steps:

- A mixture of the two oils is placed in a beaker, at 25°C. This mixture is stirred for 5 minutes at 1150 rpm.

- The fillers are then added. This mixture is stirred for 5 minutes at 1150 rpm. A Pickering emulsion is obtained.

Example 5: Emulsions prepared using methylsilsesquioxane resin microbeads

The microbeads used are sold under the name Tospearl AQ by the company Momentive. They have a mean diameter of 5 μιη. Starting materials Example 5.1 Example 5.2 Example 5.3

PDMS oil 100 cSt (g/100

g)

47.5

(Belsil DM 100 sold by

Wacker)

Castor oil (g/100 g)

(Codex sold by 47.5

Interchimie)

Triethyl citrate (g/100 g)

(Citrofol AI sold by 47.5 47.5

Jungbunzlauer)

Hydrogenated

polyisobutene (g/100 g)

47.5

(Parleam sold by NOF

Corporation)

Polyphenyltrimethylsiloxy

dimethylsiloxane (g/lOOg)

47.5

(Belsil PDM 1000 sold by

Wacker)

Methylsilsesquioxane

5 5 5

resin microbeads (g/lOOg)

Total 100 100 100

Example 6: Emulsions prepared using titanium oxide particles encapsulated in silica microspheres

The particles used are sold under the name Sunsil Tin 50 by the company Sunjin Chemical. They have a mean diameter of between 2 and 7 μιη.

Example Example

Starting materials

6.1 6.2

PDMS oil 100 cSt (g/100 g)

47.5

(Belsil DM 100 sold by Wacker)

Triethyl citrate (g/100 g)

47.5

( Citrofol AI sold by Jungbunzlauer) Castor oil (g/100 g)

47.5

(Codex sold by Interchimie)

Polyphenyltrimethylsiloxydimethylsiloxane

(g/lOOg) (Belsil PDM 1000 sold by 47.5

Wacker)

Solid particles (g/WOg) 5 5

Total 100 100

Example 7: Emulsions prepared using crosslinked polydimethylsiloxane gum beads coated with silsesquioxane resin

The particles used are sold under the name KSP 100 by the company Shin- Etsu. They have a mean diameter of 5 μιη.

Example 8: Emulsions prepared using crosslinked polydimethylsiloxane gum beads coated with silsesquioxane resin and using a pasty compound

The particles used are sold under the name KSP 100 by the company Shin- Etsu. They have a mean diameter of 5 μιη. Preparation protocol:

- The pasty compound is incorporated into the castor oil. The mixture is heated at 50°C with slow stirring using a Rayneri blender until the pasty compound has melted: about 15 minutes.

- The resulting mixture is stirred at 1100 rpm and the silicone oil is then added slowly. The mixture is stirred for a further 5 minutes after the incorporation of the oil.

- Solid particles are added and the mixture is stirred for 5 minutes.

- The heating is switched off and the mixture is allowed to cool to room temperature (about 22°C).

Example 9: Emulsions prepared using composite particles whose core is formed from crosslinked polymethyl methacrylate and whose envelope is formed from polymethylsilsesquioxane and using a pasty compound

The procedure is performed as described in Example 8. The particles used are sold under the name Silcrusta MK03® by the company Kobo (INCI name: Methyl methacrylate crosspolymer (and) polymethylsilsesquioxane).

Example 10: Emulsions prepared using crosslinked polydimethylsiloxane gum beads coated with silsesquioxane resin and using a wax

Preparation protocol:

- The wax is incorporated into the castor oil. The carnauba wax is heated to 90°C-92°C or the mixture of long-chain fatty alcohols and hydrocarbon wax is heated to 105°C with slow stirring using a Rayneri blender until the wax has melted, and the mixture is then stirred for 15 minutes.

- The resulting mixture is stirred at 1100 rpm and the silicone oil is then added slowly. The mixture is stirred for 10-15 minutes after the incorporation of the oil.

- Solid particles are added and the mixture is stirred for 15 minutes. - The heating is switched off and the mixture is allowed to cool to room temperature (about 22°C).

Example 11: Emulsions prepared using crosslinked polydimethylsiloxane gum beads coated with silsesquioxane resin and using a gelling agent

Preparation protocol:

- Gelling agent is incorporated into the castor oil. The mixture is heated at 75°C with slow stirring using a Rayneri blender until the gelling agent has melted, followed by stirring for 15 minutes.

- The resulting mixture is stirred at 1100 rpm and the silicone oil is then added slowly. The mixture is stirred for 10-15 minutes after the incorporation of the oil. - Solid particles are added and the mixture is stirred for 15 minutes.

Example 12: Emulsions prepared using spherical cellulose particles

The particles used were prepared from microparticles sold under the Cellulobeads D-5® by the company Daito Kasei.

Process for preparing the particles:

Procedure

The components indicated in the above table were mixed, in the weight ratio indicated in the table, in a plastic bag which was shaken for a few minutes. The mixture was then placed in a hybridizer machine sold under the trade name Nara Machinery® with a rotor spinning at 8000 rpm (linear speed of 100 m/s) for 3 minutes to obtain the composite pigments.

The emulsion was prepared according to the ultrasonication process described above.

The emulsions obtained in Examples 1 to 12 above have suitable stability properties.

Thus, the production of Pickering O/O emulsions was confirmed by microscope.

Moreover, all the emulsions obtained in Examples 1 to 12 were subjected to the stability test as described earlier in the description. It was thus observed that, for all the emulsions prepared, at least 50% by volume of dispersed phase remains in the form of drops after 24 hours at 20°C and atmospheric pressure.

Claims

1. Oil/oil (O/O) emulsion comprising at least:

2. Oil/oil (O/O) emulsion according to the preceding claim, in which the solid microparticles are spherical.

3. Oil/oil (O/O) emulsion according to either of the preceding claims, in which the solid microparticles are such that their largest dimension ranges from 0.15 to 100 μιη, more particularly between 0.2 and 50 μιη, in particular from 0.4 to 30 μιη, even more particularly from 0.5 to 20 μιη, preferably from 1 to 10 μιη and more preferably from 2 to 7 μιη.

4. Oil/oil (O/O) emulsion according to any one of the preceding claims, in which (i) the microparticles comprise a core comprising at least a first material; said core being covered at the surface, continuously or discontinuously, with an envelope comprising at least a second material different from the first, or alternatively (ii) at least a second material is dispersed in a matrix of at least a first material different from the second material(s).

5. Oil/oil (O/O) emulsion according to any one of the preceding claims, in which the solid microparticles in accordance with the invention are present at concentrations of less than 10% by weight relative to the total weight of the emulsion and preferably at concentrations ranging from 1% to 10% by weight relative to the total weight of the emulsion, in particular from 1% to 7% by weight.

6. Oil/oil (O/O) emulsion according to any one of the preceding claims, in which the materials included in the composition of the microparticles are chosen from the following compounds: (i) crosslinked or non-crosslinked poly(meth)acrylate and polyalkyl (meth)acrylate (co)polymers,

(ii) crosslinked organopolysiloxane elastomers,

(iv) polyamides,

(v) copolymers of styrene and of (meth)acrylic acid or a (Ci-C₂o)alkyl ester thereof under the INCI name: Styrene/ Acrylates Copolymer, polystyrene,

(vi) polyorganosilsesquioxanes, more particularly polymethyl-silsesquioxanes, (vii) mineral particles chosen more particularly from metal oxides, silicates, glass particles, silica, calcium carbonate, magnesium carbonate, magnesium hydrogen carbonate, hydroxyapatite, boron nitride, and alkali metal sulfates and phosphates; bismuth oxychloride,

(viii) cationic polymers,

(ix) poly-P-alanine, polyurea,

(x) polyethylene; polyethylene (meth)acrylate, polypropylene, polytetrafluoroethylene, polyurethanes; expanded hollow particles of vinylidene chloride and acrylonitrile polymer, and

(xi) mixtures thereof.

7. Oil/oil (O/O) emulsion according to Claim 4, the microparticles comprising a core and an envelope, in which the materials that can constitute the core of the microparticles are chosen from the materials (i), (ii), (iii), (iv), (v), (vi) and (x) according to the preceding claim, metal oxides, silicates, glass particles, silica, calcium carbonate or magnesium carbonate, magnesium hydrogen carbonate and hydroxyapatite, and mixtures thereof, and the materials that can constitute the envelope are chosen from the materials (vi) according to the preceding claim, crosslinked or non-crosslinked poly(meth) acrylate polymers, (viii), (ix), polyethylene; polytetrafluoroethylene, polyurethanes; expanded hollow particles of polymer of vinylidene chloride and of acrylonitrile, silica, for example fumed silicas, hydroxyapatites, coated or uncoated metal oxide particles, and mixtures thereof.

8. Oil/oil (O/O) emulsion according to any one of the preceding claims, in which the microparticles are chosen from: (1) microspheres comprising a core comprising at least one polyorganosiloxane, especially a polymethylsilsesquioxane, said core being covered with a cationic polymer, especially a Polyquaternium,

(2) multilayer composite spherical particles comprising:

9. Oil/oil emulsion according to any one of the preceding claims, in which said non- volatile first oil or second oil, preferably said first oil, is chosen from silicone oils and fluoro oils, or mixtures thereof, and more particularly from non-phenyl non-volatile silicone oils; phenyl non-volatile silicone oils, optionally bearing at least one dimethicone fragment; fluoro oils; or mixtures thereof.

10. Oil/oil emulsion according to any one of the preceding claims, in which the non-volatile first or second oil, preferably the second oil, is chosen from polar hydrocarbon-based non-volatile oils, in particular chosen from non-volatile oils comprising not more than one free hydroxyl group or not comprising any, or from non-volatile oils comprising at least two free hydroxyl groups, or from apolar hydrocarbon-based nonvolatile oils, or mixtures thereof.

11. Oil/oil emulsion according to any one of the preceding claims, in which the first oily phase contains at least a first oil chosen from non-volatile silicone oils and the second oily phase contains at least a second oil chosen from non-volatile apolar hydrocarbon-based oils.

12. Oil/oil emulsion according to any one of Claims 1 to 10, in which the first oily phase contains at least a first oil chosen from non-phenyl non-volatile silicone oils or phenyl non- volatile silicone oils bearing at least one dimethicone fragment, and the second oily phase contains at least a second oil chosen from non- volatile hydrocarbon-based oils comprising not more than one free hydroxyl group or not comprising any.

13. Oil/oil emulsion according to any one of Claims 1 to 10, in which the first oily phase contains at least a first oil chosen from non- volatile silicone oils and the second oily phase contains at least a second oil chosen from non-volatile hydrocarbon-based oils comprising at least two free hydroxyl groups and preferably at least three free hydroxyl groups.

14. Oil/oil emulsion according to any one of Claims 1 to 10, in which the first oily phase contains at least a first oil chosen from phenyl non-volatile silicone oils not bearing a dimethicone fragment, and the second oily phase contains at least a second oil chosen from non-volatile hydrocarbon-based oils comprising at least two free hydroxyl groups and preferably at least three free hydroxyl groups, or from non-volatile apolar hydrocarbon-based oils.

15. Oil/oil emulsion according to any one of Claims 1 to 10, in which the first oily phase contains at least a first oil chosen from non-volatile polar hydrocarbon-based oils and the second oily phase contains at least a second oil chosen from non-volatile apolar hydrocarbon-based oils.

16. Oil/oil emulsion according to any one of Claims 1 to 10, in which the first oily phase contains at least a first oil chosen from non-phenyl non-volatile silicone oils and the second oily phase contains at least a second oil chosen from phenyl non-volatile silicone oils optionally bearing at least one dimethicone fragment, or at least one volatile silicone oil.

17. Oil/oil emulsion according to any one of Claims 1 to 10, in which the first oily phase contains at least a first oil chosen from phenyl non-volatile silicone oils not bearing a dimethicone fragment, and the second oily phase contains at least a second oil chosen from phenyl non- volatile silicone oils bearing at least one dimethicone fragment, or at least one volatile silicone oil.

18. Oil/oil emulsion according to any one of the preceding claims, in which the oil content of the first oily phase represents from 5% to 95% by weight and preferably from 30% to 70% by weight, relative to the weight of the emulsion.

19. Oil/oil emulsion according to any one of the preceding claims, in which the oil content of the second oily phase represents from 5% to 95% by weight and preferably from 30% to 70% by weight, relative to the weight of the emulsion.

20. Oil/oil emulsion according to any one of the preceding claims, in which the weight ratio of the oil(s) of the first oily phase relative to the oil(s) of the second oily phase represents from 5/95 to 95/5 and preferably from 30/70 to 70/30.

21. Oil/oil emulsion according to any one of the preceding claims, also comprising at least one structuring agent chosen from waxes, pasty compounds, polymeric thickeners and mineral thickeners, and mixtures thereof.

22. Cosmetic composition comprising, in a physiologically acceptable medium, at least one oil/oil emulsion according to any one of the preceding claims.

23. Use of solid microparticles having at least one curved part whose radius of curvature is not infinite, the largest dimension of which is at least 0.15 μιη and comprising at least two different materials, each mineral or organic, for stabilizing an O/O emulsion comprising at least a first oily phase comprising at least a first non-volatile oil chosen from silicone oils, hydrocarbon-based oils and fluoro oils, and at least a second oily phase comprising at least a second volatile or non-volatile oil that is immiscible with the first oil(s) at 25°C.