WO2002055649A1

WO2002055649A1 - Micro-capsules containing washing and cleaning substances

Info

Publication number: WO2002055649A1
Application number: PCT/EP2001/014782
Authority: WO
Inventors: Ute Krupp; Wolfgang Von Rybinski; Dieter Nickel; Michael Dreja
Original assignee: Henkel Kommanditgesellschaft Auf Aktien
Priority date: 2001-01-09
Filing date: 2001-12-14
Publication date: 2002-07-18
Also published as: EP1349913A1; DE10100689A1

Abstract

A method for the production of micro-capsules containing washing and/or cleaning substances with semi-permeable capsule shells (membranes) by means of complexing suitable polyelectrolytes is disclosed. Microcapsules produced thus are suitable, for example, for application in washing and cleaning agents.

Description

"Microcapsules containing washing and cleaning-active substances"

The present invention relates to a process for the production of microcapsules containing detergent and / or cleaning agents with a semipermeable capsule shell (membrane) by complexing suitable polyelectrolytes, and to the microcapsules produced in this way containing detergent and cleaning agents and their use, in particular in washing and Detergents, cosmetic products and personal care products.

In addition to surfactants, detergents and cleaning agents contain additional active ingredients and auxiliaries that are active in washing and cleaning, which are incorporated into the formulation. However, it is not uncommon for problems to arise in the formulation as a result of the chemical properties of the active ingredients. Negative interactions can be in particular: destabilization of emulsions (e.g. BAC in fabric softener), decomposition of the active ingredients after prolonged storage (e.g. amino-functional silicone oils in acid detergents), general incompatibility of individual ingredients (e.g. complexation of QAVs with anionic surfactants).

Microcapsules or particles are used in particular in pharmacy, e.g. B. to increase the stability of the active ingredients, to cover taste, for targeted organ-specific release of active ingredients and also to avoid incompatibilities with other auxiliaries and active ingredients. Microcapsules are also used in adhesive technology. Also known are fragrance capsules with gelatin as wall material, from which perfume oils are released by mechanical destruction. In general, these microcapsules are particles with diameters _ 1 mm.

In addition to "real" microcapsules, which have a shell / core structure, there are spherical carrier particles z. B. from alginate, gelatin or polyvinyl alcohol (PVAI), in which an active ingredient, living cells or enzymes can be embedded. These capsules can e.g. B. be produced by a dripping process, wherein to increase the mechanical stability, the carrier material is crosslinked physically or chemically.

Mechanical destruction is the most common release mechanism for capsule ingredients in non-pharmaceutical applications (e.g., when a screw is screwed into a thread that has previously been applied with an adhesive that contains encapsulated components). The forces required for this are great. However, such forces do not occur reliably when using detergents and cleaning agents, so that such capsule systems are unsuitable for these applications.

In cosmetic products, e.g. B. shampoos, macro balls made of gelatin or alginate, which are loaded with a hydrophobic active ingredient, are used. Since the carrier material is not soluble under the conditions of use, the active ingredient is also released here by mechanical destruction of the capsules. However, the forces to be used for this must be relatively high, and often undesirable residues remain.

Conventional alginate macrospheres which are produced by complexing with calcium ions also have the disadvantage that they cannot be used in compositions which contain a complexing agent, since the complexing agent leads to the capsules being dissolved in the long term. This limitation applies in particular to liquid detergents.

EP 0 782 853 A2 and the corresponding DE 195 19 804 A1 describe bioactive capsules with a variable shell, in particular for use in living tissue or in biotechnological applications, with a core containing living cells and / or enzymes and a shell consisting of several , the core is built up completely surrounding individual layers, which consist of a porous network of intertwined macromolecules, at least one of the layers consisting of a material that changes or dissolves the structure as a function of an ion concentration and / or physical quantities and / or by reagents , WO 99/02252 describes a process for the production of high-strength capsules which have a core made of a polyanionic polysaccharide, which is coated with a polycationic polysaccharide membrane. The capsules described there are used in particular in the field of pharmacy, but also in the field of catalysis, biology, pesticides and herbicides, agriculture, cosmetics and the food industry.

US-A-4,352,883 describes a method for encapsulating living tissue, single cells, hormones, enzymes or antibodies in a semi-permeable membrane which is permeable to small molecules but is impermeable to potentially harmful large molecules. The semipermeable membrane is applied to discrete, temporary capsules or gel droplets that retain their shape, the gel then being liquefied again.

US-A-4 690 682 describes a dosing system for the controlled release of substances with a substantially constant delivery quantity. These are capsules with a semipermeable membrane, which contain a material to be released in encapsulated form. The release genetics should be controllable via the pore size of the membranes.

WO 91/15196 describes an osmotic dosing system for active pharmaceutical ingredients, which consists of an outer semipermeable membrane, an osmotically active middle layer and an inner capsule, which comprises a liquid formulation with the active pharmaceutical ingredient.

DE 197 12 978 A1 describes chitosan microspheres which are obtained by mixing chitosans and / or chitosan derivatives with oil bodies and then introducing the mixture into alkaline surfactant solutions, so that microcapsules filled with oil bodies are formed. In this way, lipophilic phases can be encapsulated and can then be incorporated as active substance depots in formulations containing surfactants. WO 00/46337 describes a liquid cleaning composition which comprises more than 5% by weight of a surfactant and more than 10% by weight of an encapsulated active substance and a crosslinked anionic rubber material. The active ingredient is in particular a fragrance.

EP 0 280 155 B1 describes the microencapsulation of biologically active material by producing a semipermeable membrane which consists of a biocompatible, non-toxic polyacid and a polybase, the polybase being formed from a special polymer with special, defined, repeating monomer units.

Denkbas et al., "Chitosan Microspheres and Sponges: Preparation and Characterization" in Journal of Applied Polymer Science, Volume 76, pages 1637-1643 (2000) describe studies on the formation of chitosan microcapsules and networks for various biomedical applications. Chitosan microcapsules and networks are formed in a suspension medium which contains chitosan, acetic acid, an emulsifier and a crosslinking agent, namely glutaraldehyde.

Bartkowiak et al., "Alginate-Oligochitosan Microcapsules: A Mechanistic Study Relating Membrane and Capsule Properties to Reaction Conditions" in Chem. Mater. 1999, 11, pages 2486-2492 examine the mechanism of microcapsule production by polyelectrolyte complexation reactions between oppositely charged polysaccharides, one of which is an oligomer. The ionic strength and the pH of the solution used in the capsule formation influence the structure of the membrane. The investigations are carried out on an alginate-oligochitosan system.

Extra wide, "Self-organized, semi-permeable capsules with diameters in the sub-micrometer range" in Angew. Chem. 1999, 111, No. 19, pages 3044-3046 describes the self-assembly of ions for the formation of semipermeable capsules for the design of new materials which are relevant to questions of catalysis, of Sensor designs, biochemistry and materials science should be relevant.

Yamamoto et al., "Polyion complex fiber and capsule formed by self-assembly of chitosan and gellan at solution interfaces" in Macromol. Chem. Phys. 201, No. 1, pages 84-92 describe the formation of polyionic complexes (PIC) by reaction of a polyelectrolyte with an oppositely charged polyelectrolyte in aqueous solution. To ensure that the encapsulated material is securely enclosed, the authors recommend subsequent coating of the microcapsule with another polymer.

Dautzenberg et al., "Polyelectrolyte complex formation at the interface of solutions" in Progr. Colloid. Polym. Be. (1996) 101: pages 149-156, Steinkopff-Verlag, investigate the kinetics of the reaction between oppositely charged polyelectrolytes at the interface of their aqueous solutions, thereby forming microcapsule membranes which are formed from the reaction components sodium cellulose sulfate and poly (diallyldimetylammonium chloride) , The authors investigate the kinetics of membrane formation.

Kokufuta, "Polyelectrolyte-coated microcapsules and their potential applications to biotechnology" in Bioseperation 7: Pages 241-252 (1999) describe polyelectrolyte-coated microcapsules which are produced by adsorption of polyions on microcapsule surfaces in aqueous solution under suitable pH values and ionic conditions can be. The authors investigate the pH-dependent control of the permeability of the capsule walls as a function of changes in the adsorbed polyion layer.

In the previously discussed prior art, no suitable capsule systems have been described so far, which can also be used in detergents and cleaning agents.

The present invention is therefore based on the object of providing a capsule system which enables a wide range of applications. On such a system should be usable in particular in detergents and cleaning agents, preferably liquid detergents and cleaning agents, fabric softeners and laundry aftertreatment agents, but also in other products, such as cosmetic products and personal care products. In particular, such a capsule system should have a relatively large storage stability even in water-containing products, but nevertheless enable a quick, easily inducible release of the ingredients during use and be able to be dissolved or removed without residue after use.

The applicant has now surprisingly found that the object on which the invention is based is achieved by a capsule system which opens because of osmotic effects. This is accomplished by providing capsules with a semi-permeable polymer membrane that is permeable to small molecules such as solvent and water molecules, but is impermeable or substantially impermeable to the encapsulated ingredients (e.g. enzymes), i.e. H. at least of the encapsulated ingredients is considerably slower than what happens to the solvent and water molecules. If the concentration of the substances dissolved in the capsules is adapted to the concentration of the substances in the surrounding medium (e.g. FWM), the capsules are stable. Do the concentrations change in the continuous phase, e.g. B. by dilution with water, there is a high osmotic pressure in the capsules, which causes them to burst or swell and thus to release the ingredients.

The present invention thus relates to a process for the preparation of microcapsules containing detergent and / or cleaning substances with a semipermeable capsule shell (membrane), which is characterized by an in-situ complexation of suitable polyelectrolytes or polyelectrolyte mixtures in the presence of an aqueous solution or dispersion

- at least one active washing and / or cleaning substance,

- if necessary, at least one further ingredient and

- If necessary, at least one matrix-forming material, so that a semipermeable capsule shell (membrane) comprising the complexed polyelectrolytes (mixtures) is formed, which covers the washable and / or cleaning-active substance, completely encloses the optionally present further ingredient and the optionally present matrix-forming material.

The complexation reaction can be followed, if appropriate after a curing step, by removing the microcapsules. Methods which are known per se and are familiar to the person skilled in the art are used here, such as in particular filtration, freeze-drying (lyophilization) or spray drying, preferably filtration. Here, excessive shear forces should not be exerted on the microcapsules so that they are not damaged.

The optionally carried out separation step can then optionally be followed by a method step in which at least one further semipermeable membrane layer is applied to the previously produced inner semipermeable capsule shell, wherein the additional membrane layer (s) can be constructed from the same or different material as the innermost capsule shell. In this way, microcapsules with a multilayer semipermeable capsule shell are produced. Multi-layer casings can be produced, for example, by repeated dipping in suitable polymer solutions.

In particular, the method according to the invention comprises the following method steps:

Provision of a first solution or dispersion which contains at least one polyelectrolyte, at least one washing and / or cleaning substance and optionally at least one further ingredient, - Provision of a second solution or dispersion which contains at least one oppositely charged electrolyte or polyelectrolyte or at least one oppositely charged Contains surfactant or a mixture of electrolytes, polyelectrolytes or surfactants in the same or opposite positions, - Complexation of the polyelectrolyte by combining or bringing the two solutions or suspensions into contact, in particular by dropping one solution or dispersion into the other, preferably by dropping the first solution or dispersion into the second solution or dispersion, so that a semipermeable capsule shell (membrane) trains which completely surrounds the ingredients to be included,

- If necessary, curing of the capsule shell (membrane) formed in this way and finally

- If necessary, separation of the microcapsules obtained in this way and

optionally applying at least one further semipermeable membrane layer made of identical or different membrane material to the innermost capsule shell, optionally followed by a separation step,

wherein the first solution or dispersion can optionally also contain at least one matrix-forming material and the second solution or dispersion in this case can optionally also contain polyvalent metal ions (e.g. alkaline earth metal ions). Such multivalent metal ions can cause additional crosslinking of the matrix-forming material.

The concentrations of the various starting materials in the first and second solution or dispersion can vary within a wide range. For example, the concentration of polyelectrolyte in the first solution or dispersion can be 0.001 to 100 g / l, in particular 0.01 to 50 g / l. The concentration of any further ingredient (for example salts such as NaCl) in the first solution or dispersion can be, for example, 0.1 to 500 g / l, in particular 1 to 500 g / l.

The concentration of oppositely charged electrolyte or polyelectrolyte or of oppositely charged surfactant or of a mixture of electrolytes, polyelectrolytes or surfactants in the same or opposite positions can, for example, be equally 0.001-100 g / l, in particular 0.01-50 g / l. If a mixture of electrolytes, polyelectrolytes or surfactants with the same or opposite charge is used in the second solution or dispersion, For example, the mixing ratio of substances stored in the same or opposite directions can be between 1:99 and 99: 1, in particular between 15:85 and 85:15.

If the method according to the invention is carried out in the absence of a matrix-forming material, coreless capsules are formed, i. H. Capsules without a matrix core, which contain at least one washing and / or cleaning active substance and optionally at least one further ingredient, encased by the semipermeable membrane.

If the method according to the invention is carried out in the presence of a matrix-forming material, nucleated capsules are formed, i. H. Capsules with a matrix core, which is completely enclosed by the semipermeable capsule shell (membrane) and in which the washing and / or cleaning substance and optionally the further ingredient is embedded or embedded. This increases the stability of the capsules.

The semipermeable capsule shell (membrane) is formed in that a polyelectrolyte undergoes a complexation reaction with an oppositely charged electrolyte or polyelectrolyte or with an oppositely charged surfactant or with a mixture of equally and oppositely charged electrolytes, polyelectrolytes or surfactants.

Suitable surfactants according to the invention are all anionic or cationic surfactants known per se, provided that they form a stable complex with the polyelectrolyte and are in particular compatible with the capsule shell material formed in this way, in particular do not dissolve it.

Polyelectrolytes suitable according to the invention can be synthetic and natural polyelectrolytes.

Anionic synthetic polyelectrolytes suitable according to the invention can in particular be selected from the group of polyacrylates and methacrylates, polyvinyl sulfates, polystyrene sulfonates and polyphosphates. Cationic synthetic polyelectrolytes suitable according to the invention can in particular be selected from the group of poly (N, N, N-trialkylammonium alkyl acrylate) cations, poly (N-alkylpyridinium) cations, cations of linear polyethyleneimines, cations of aliphatic ions and poly ( dimethyldiallylammonium) ammonium cations.

Anionic polyelectrolytes of natural origin which are suitable according to the invention can in particular be selected from the group of alkali metal and alkaline earth metal carboxymethyl celluloses, alkali metal and alkaline earth metal cellulose sulfates, alkali metal and alkaline earth metal celluronates, alkali metal and alkaline earth metal carrageenans, alkali metal and alkaline earth metal hyaluronates, and alkali metal and alkaline earth metal - lignosulfonates and alkali and alkaline earth polyribonucleates. Cationic polyelectrolytes of natural origin suitable according to the invention can in particular be selected from the group of chitosans and chitosan derivatives such as quaternized chitosans, aminoalkylated and subsequently quaternized celluloses and poly-L-lysine.

Polyelectrolytes suitable according to the invention can also be polyampholytes, in particular polyampholytes on a natural basis, preferably on the basis of natural polypeptides.

In particular, the semipermeable capsule shell (membrane) can be formed by complexing reaction of at least one of the following polyelectrolyte complexing pairs:

Polyvinylamine / polyvinyl sulfate,

Polyvinylamine / dextran sulfate,

- polyethyleneimine / polyvinyl sulfate,

- polyethyleneimine / cellulose sulfate, polyethyleneimine / chitosan sulfate,

Polyethyleneimine / polyacrylic acid or polyacrylic acid copolymer (s), poly (allylamine hydrochloride) / dextran sulfate,

- poly-L-lysine / polyacrylic acid, chitosan / dextran sulfate, chitosan / cellulose sulfate, chitosan / chitosan sulfate, - chitosan / polyacrylic acid,

- chitosan / carboxymethyl cellulose,

- poly (4-vinylpyridine) / sodium polystyrene sulfonate, poly (4-vinylpyridine) / cellulose sulfate,

Poly (diallyldimethylammonium chloride) / sulfoethyl cellulose or cellulose sulfate,

- poly (diallyldimethylammonium chloride) / dextran sulfate,

- poly (diallyldimethylammonium chloride) / polyacrylic acid.

The semipermeable capsule shell (membrane) can also be formed, for example, by complexing reaction of at least one polyelectrolyte with at least one surfactant, in particular cellulose sulfate / N-dodecylpyridinium chloride.

Furthermore, the semipermeable capsule shell (membrane) can also be formed by complexing reaction of at least one cationic polyelectrolyte with at least one anionic layered silicate, in particular poly (diallyldimethylammonium chloride) / montmorillonite.

The wash- and / or cleaning-active substance is selected in particular in such a way that it cannot or essentially cannot pass through the semipermeable membrane. At least the washing and / or cleaning active substance should diffuse through the semipermeable capsule shell (membrane) considerably more slowly, preferably by at least an order of magnitude, than water molecules.

The washing and / or cleaning active substance can in particular be selected from the group of washing and / or cleaning active inorganic and organic acids, in particular carboxylic acids, soil repellent and soil release active ingredients, bleaching agents such as hypochlorites, washing and cleaning active enzymatic Systems and enzymes such as amylases, cellulases, lipases and proteases, fragrances, in particular perfume oils, antimicrobial agents, in particular antibacterial, antiviral and / or fungicidal agents, graying and discoloration inhibitors, active substances for color protection, substances and additives for laundry care, surfactants, especially surfactants with fabric softener properties, as well as pH adjusting agents and pH buffer substances.

In particular, the washing and / or cleaning-active substance is selected such that it is compatible with the capsule shell, preferably inert towards the capsule shell material. Furthermore, it should also be compatible with the other capsule ingredients.

The additional ingredient which may be present is selected in particular in such a way that it too cannot or essentially cannot pass through the semipermeable capsule shell (membrane) or at least diffuses considerably more slowly, preferably at least one order of magnitude slower, than water molecules through the semipermeable capsule shell (membrane) , Furthermore, it should be inert to the capsule shell material and / or should preferably have no surfactant properties. The further ingredient is selected in particular in such a way that, when diluted, in particular with water, it builds up an osmotic pressure in the interior of the capsule which can explode the capsule. Other ingredients suitable according to the invention can in particular be selected from the group of alcohols, glycols, in particular polyethylene and polypropylene glycols, ionic and polar compounds, inorganic and organic salts and sugars of all kinds.

According to the invention, if present, the matrix-forming material can be selected in particular from the group of pectins, agar-agar, xanthanes, guar gum, gelatins, gel formers, polyvinyl alcohols (PVAI), gellan gum, carrageenan, starch derivatives and polysaccharides.

The reaction time for the process according to the invention can vary within wide ranges. In particular, the complexation reaction proceeds spontaneously.

The temperatures at which the process according to the invention is carried out can vary within wide limits. In general, the invention Process at temperatures from 0 to 100 ° C, in particular 20 to 60 ° C, preferably at room temperature.

The pH values at which the process according to the invention is carried out can vary within wide ranges. In general, the process according to the invention is carried out at pH values from 0 to 10, in particular from 1 to 6.

The pressures at which the process according to the invention is carried out can vary within a wide range. In general, the process according to the invention is carried out under reduced, elevated or normal pressure, preferably under normal pressure.

As described above, the stability of the capsules according to the invention can be increased by applying a polymer membrane to a solid core in which the ingredients are embedded. The membrane can be constructed, for example, from one or more layers of oppositely charged polyelectrolytes, which are held together due to electrostatic interactions, or other (bio) polymers. Multi-layer casings can be produced, for example, by repeated dipping in polymer solutions or by methods such as spray drying.

As described above, in the case of capsules containing matrix kernels, the core of the capsules can e.g. B. consist of polyvinyl alcohols, starch derivatives, gelatin, etc. In addition, however, carrier materials made of other polymers are also conceivable, which can form a matrix for encapsulating active ingredients. It is particularly advantageous if the matrix formation is reversible, for example in the case of certain starches which are physically crosslinked by polyvalent ions. This means that any stabilities can be set.

An important aspect in the production of the capsules according to the invention, which are intended to burst due to osmotic effects during use, is the fact that the concentrations of the auxiliaries are already at the level of the core prevailing concentrations in the later storage medium can be adjusted.

As explained above, the microcapsules according to the invention with a semipermeable wall membrane are produced, for example, by complexing a polyelectrolyte, such as, for. B. chitosan, with vesicles from a complex mixture of cationic and anionic, d. H. equally charged and oppositely charged surfactants. Alternatively, for example, two oppositely charged polyelectrolytes or a polyelectrolyte and an oppositely charged surfactant can also be complexed together. For this purpose, for example, appropriately concentrated solutions of the polymers or of surfactant (s) and polymer can be combined, in particular by dropping. In general, capsules spontaneously form which have a semipermeable membrane shell. This shell is generally permeable to the diffusion of water, but impermeable to ingredients dissolved therein, or only significantly slower, preferably at least an order of magnitude slower, can be passed through diffusion than in the case of water molecules.

The present invention also relates to the microcapsules obtainable by the process according to the invention. These are, in particular, microcapsules with a semipermeable capsule shell (membrane) which, in addition to water, contain at least one washing and / or cleaning active substance and optionally at least one further ingredient in the interior of the capsule, the washing and / or cleaning active substance and optionally the further ingredient can be embedded in a matrix-forming material, the semipermeable capsule shell (membrane) comprising a polyelectrolyte complex and the shell consisting of at least one layer of such polyelectrolyte complexes and the semipermeable membrane being permeable to water molecules and to the encapsulated washing and / or cleaning-active substances and preferably also is impermeable to the further ingredient and the matrix-forming material or at least one order of magnitude slower than can be passed to water moles, so that when the microcapsules are introduced into an aqueous phase, an osmotic pressure can build up inside the capsule, causing the capsules to burst.

The semipermeable capsule shell (membrane) of the capsules according to the invention is therefore generally permeable to water molecules, but impermeable or - in comparison to water molecules - at least only passable much more slowly to the detergent and / or cleaning substance and preferably also impermeable or - in comparison to water molecules - at least passable only much more slowly for the possibly present further ingredient and the possibly existing matrix material. The term "considerably slower" in the present case means in particular "at least one order of magnitude slower", based on the rate of diffusion at which the molecules diffuse through the semipermeable capsule shell (membrane).

In general, the microcapsules according to the invention have average diameters of 1 to 5,000 μm, in particular 50 to 3,000 μm, preferably 100 to 2,000 μm.

The content of encapsulated ingredients can - depending on the desired properties of the capsules and properties of the starting materials - vary within a wide range. The desired content in the end product (= capsule) can then be set by measuring the amounts of the starting materials.

In general, the microcapsules according to the invention contain 1 to 99% by weight, in particular 1 to 60% by weight, preferably 2 to 50% by weight, of the detergent and / or cleaning agent, based on the total weight of the microcapsules.

In general, the microcapsules according to the invention contain 1 to 99% by weight, in particular 1 to 60% by weight, preferably 2 to 50% by weight, of the further ingredient, based on the total weight of the microcapsules. In general, in the case of capsule-containing capsules, the microcapsules according to the invention can contain 0.1 to 50% by weight, in particular 0.5 to 30% by weight, preferably 0.5 to 10% by weight, of the matrix-forming material included, based on the total weight of the microcapsules. The microcapsules according to the invention have a wide range of applications. They can be used in particular in washing and cleaning agents, preferably liquid washing and cleaning agents, fabric softeners, post-washing agents and the like, in cosmetic products and in products for personal care. They are suitable as an osmosis-controlled metering system, in particular for use in detergents and cleaning agents, preferably liquid detergents and cleaning agents, fabric softeners, laundry aftertreatment agents and the like.

The present invention thus also relates to detergents and cleaning agents, in particular liquid detergents and cleaning agents, fabric softeners, laundry aftertreatment agents and the like, which contain the microcapsules according to the invention. The content of the microcapsules according to the invention can vary within wide limits. In general, the microcapsules according to the invention are used in amounts of 0.01 to 30% by weight, in particular 0.1 to 20% by weight, preferably 1 to 10% by weight, based on the detergent and cleaning agent.

As described above, it is therefore possible to use the effect of an osmotic pressure difference as the opening mechanism of the capsules according to the invention. Such osmotic pressure can e.g. B. generated by different concentrations of salt in the capsule and the surrounding outer phase, as they usually occur with dilutions. By using the capsules according to the invention with a membrane-like coating, which is impermeable to salts or at least only diffuses more slowly than water molecules, but is designed to be permeable to water molecules, this effect can be exploited by, for example, either including salt in the interior of the capsule or but the capsules can also be placed in a saline solution without the inclusion of salt.

Are the capsules according to the invention with a semipermeable membrane shell, for example with a solution in the interior of the capsule, with a content of approx. 10% NaCI or filled with an alcoholic solution and these capsules are brought into an essentially salt-free environment, for example by dilution, so water diffuses into the interior of the capsule. This creates a positive pressure difference between the interior of the capsule and the environment, which ultimately leads to the capsule being blown up. The further content of the capsule is released.

The present invention has a number of advantages over the known prior art:

The encapsulated ingredients are released regardless of the temperature by a dilution step. When using z. B. in liquid detergents used in washing machines, the capsules according to the invention can consequently be used in all temperature programs. The action of mechanical forces is also not necessary.

In general, very thin membrane layers are sufficient to enclose the ingredients. If the ingredients are additionally embedded in a (initially) solid matrix core which is enveloped by the membrane, additional stabilization of the capsules according to the invention is achieved. The “mesh size” or pore size of the semipermeable membrane can be set in a targeted manner, inter alia, by the choice of the polymers or the number of the individual layers. The stability of the membrane can also be increased by chemical cross-linking. In addition, it is possible to change the membrane structure in pH- and / or temperature-sensitive polymers by changing the external environmental conditions so that the permeability for individual substances changes selectively.

The semipermeable polymer membrane also allows the use of such polysaccharides as carrier matrix (= matrix core) which would otherwise not be stable in a medium which contains complexing agents. Due to the semi-permeable protective cover, the enclosed substance (e.g. a detergent enzyme) "held" even if the matrix core is subsequently liquefied. This has the advantage that no residues remain.

Furthermore, the capsule systems according to the invention have the advantage that they are stable in storage even in water-containing products, that they enable quick, easily inducible release of the ingredients during use and that they can be dissolved or removed without residue after use.

Further configurations and variations of the present invention are readily recognizable and realizable for the person skilled in the art on reading the description, without thereby leaving the scope of the present invention.

The present invention is illustrated by means of the following exemplary embodiments, which, however, in no way limit the invention.

EMBODIMENTS:

EXAMPLE 1 Production of Capsules According to the Invention With a Matrix Core A 0.1 N NaCl solution with 2% pectin is mixed with 2 ml of perfume oil and with 5% glucose and with a dropping apparatus (such as from Brace, for example) in a precipitation bath dripped with 1.5% CaCl2, which also contains chitosan and citric acid. After a curing time of at least 10 minutes, the resulting balls can be filtered off.

Example 2: Use of the capsules from example 1 in a liquid detergent

3% of the capsules produced in Example 1 are stirred into a gel-form liquid detergent (see below for frame formulation). After a few days, the pectin core becomes due to the interaction of the complexing agents with the calcium ions partially re-liquefied from the pectin matrix. However, the active cleaning ingredient remains enclosed in the capsule by the membrane.

The contents are released by diluting the detergent (e.g. by a factor of 1: 100). A high osmotic pressure develops in the capsules, which leads to the membrane bursting and the contents being released.

Recipe example liquid detergent

Component share (%)

APG (alkyl polyglycosides) 1-5

Glycerin 5-10

Fatty alcohol ether sulfate 2-10

Fatty alcohol ethoxylate 15-28

Sodium citrate 0.5-5

NaOH 2-5

Sokalan HP 56 0.1-1

Soap 5-18

Perfume 0.2-2

Enzymes 0.01-2

Glucose 1-8

Water rest

Example 3: Production of capsules according to the invention without a matrix core. Capsules were prepared by complexing polyelectrolytes with surfactant mixtures with salt content, which show an osmotic switching effect, according to the following recipe:

A solution of 2 g of chitosan (Hydagen CMF) and 10 g of NaCl in 100 ml of water was acidified with 2 g of citric acid and dissolved with heating. The solution was added dropwise to a 0.8% by weight solution of Texapon K1298 (sodium lauryl sulfate) and Dehyquart LDB 50 (lauryldimethylbenzylammonium chloride) (mixing ratio 74:26) using a syringe at 30 ° C. Capsules of a few millimeters in diameter spontaneously formed which could be filtered off. When these capsules were transferred to demineralized water, they burst within a few minutes and released citric acid so that the pH of the solution dropped. The capsules according to the invention act as an osmosis switch. Corresponding capsules without a semipermeable wall membrane do not have the described effect.

Likewise, it is possible to produce capsules without salt content, which then contract when transferred to a salt solution (e.g. a 10% by weight NaCl solution), i. H. show an inverse osmosis effect and thus release citric acid.

Claims

claims:

1. A process for the preparation of microcapsules containing detergent and / or cleaning substances with a semipermeable capsule shell (membrane), characterized by an in-situ complexation of suitable polyelectrolytes or polyelectrolyte mixtures in the presence of an aqueous solution or dispersion

- at least one active washing and / or cleaning substance,

- if necessary, at least one further ingredient and

- If necessary, at least one matrix-forming material, so that a semipermeable capsule shell (membrane) comprising the complexed polyelectrolytes (mixtures) is formed, which completely encloses the washing and / or cleaning-active substance, the optionally present further ingredient and the optionally present matrix-forming material.

2. The method according to claim 1, characterized in that the complexation reaction, optionally after a curing step, is followed by a separation of the microcapsules.

3. The method according to claim 2, characterized in that after the separation of the microcapsules at least one further semipermeable membrane layer is applied to the capsule shell, the material from which the further membrane layer consists may or may not be identical to the capsule shell material of the inner layer.

4. The method according to any one of claims 1 to 3, characterized by the following process steps:

Provision of a first solution or dispersion which contains at least one polyelectrolyte, at least one washing- and / or cleaning-active substance and optionally at least one further ingredient, Provision of a second solution or dispersion which contains at least one oppositely charged electrolyte or polyelectrolyte or at least one oppositely charged surfactant or a mixture of electrolytes, polyelectrolytes or surfactants in the same or opposite positions,

- Complexation of the polyelectrolyte by combining or bringing the two solutions or suspensions into contact, in particular by dropping one solution or dispersion into the other, preferably by dropping the first solution or dispersion into the second solution or dispersion, so that a semipermeable capsule shell ( Membrane) which completely surrounds the ingredients to be enclosed,

- If necessary, separation of the microcapsules obtained in this way and

if appropriate, applying at least one further semipermeable membrane layer made of identical or different membrane material to the innermost capsule shell, optionally followed by a separation step.

5. The method of claim 4, wherein the first solution or dispersion also contains at least one matrix-forming material and the second solution or dispersion optionally also contains polyvalent metal ions.

6. The method according to any one of claims 1 to 5, characterized in that the formation of the semipermeable capsule shell (membrane) takes place in that a polyelectrolyte undergoes a complexation reaction with an oppositely charged electrolyte or polyelectrolyte or with an oppositely charged surfactant or with a mixture of the same - And received oppositely charged electrolytes, polyelectrolytes or surfactants.

Method according to one of claims 1 to 6, characterized in that the polyelectrolytes are selected from the group of synthetic and natural polyelectrolytes.

8. The method according to any one of claims 1 to 7, characterized in that at least one of the polyelectrolytes is an anionic or cationic synthetic polyelectrolyte.

9. The method according to claim 8, characterized in that the anionic synthetic polyelectrolyte is selected from the group of polyacrylates and methacrylates, polyvinyl sulfates, polystyrene sulfonates and poly-phosphates.

10. The method according to claims, characterized in that the cationic synthetic polyelectrolyte is selected from the group of poly (N, N, N-trialkylamonium alkyl acrylate) cations, poly (N-alkyl pyridinium) cations, cations of linear polyethyleneimines, cations aliphatic ions and poly (dimethyldiallyl) ammonium cations.

11. The method according to any one of claims 1 to 10, characterized in that at least one of the polyelectrolytes is an anionic or cationic natural polyelectrolyte.

12. The method according to claim 11, characterized in that the anionic natural polyelectrolyte is selected from the group of alkali and alkaline earth carboxymethyl celluloses, alkali and alkaline earth cellulose sulfates, alkali and alkaline earth cellulose uronates, alkali and alkaline earth carrageenans, alkali and alkaline earth alkali paralins and alkali paraline , Alkali and alkaline earth lignosulfonates as well as alkali and alkaline earth polyribonucleates.

13. The method according to claim 11, characterized in that the cationic natural polyelectrolyte is selected from the group of chitosans and chitosan derivatives such as quaternized chitosans, aminoalkylated and then quaternized celluloses and poly-L-lysine.

14. The method according to any one of claims 1 to 13, characterized in that at least one of the polyelectrolytes is a polyampholyte, in particular a natural polyampholyte, preferably based on natural polypeptides.

15. The method according to any one of claims 1 to 14, characterized in that the formation of the semipermeable capsule shell (membrane) is carried out by complexing reaction of at least one of the following polyelectrolyte complexing pairs:

- polyvinylamine / polyvinyl sulfate,

- polyvinylamine / dextran sulfate,

- polyethyleneimine / polyvinyl sulfate,

- polyethyleneimine / cellulose sulfate,

- polyethyleneimine / chitosan sulfate,

- polyethyleneimine / polyacrylic acid or polyacrylic acid copolymer (s),

- poly (allylamine hydrochloride) / dextran sulfate,

- poly-L-lysine / polyacrylic acid,

- chitosan / dextran sulfate,

- chitosan / cellulose sulfate,

- chitosan / chitosan sulfate,

- chitosan / polyacrylic acid,

- chitosan / carboxymethyl cellulose,

Poly (4-vinylpyridine) / sodium polystyrene sulfonate,

Poly (4-vinylpyridine) / cellulose sulfate,

- poly (diallyldimethylammonium chloride) / dextran sulfate,

- poly (diallyldimethylammonium chloride) / polyacrylic acid.

16. The method according to any one of claims 1 to 14, characterized in that the formation of the semipermeable capsule shell (membrane) by complexing reaction of at least one polyelectrolyte with at least one surfactant, in particular cellulose sulfate / N-dodecylpyridinium chloride, takes place.

17. The method according to any one of claims 1 to 14, characterized in that the formation of the semipermeable capsule shell (membrane) by complexing reaction of at least one cationic polyelectrolyte with at least one anionic layered silicate, in particular poly (diallyldimethylammonium chloride) / montmorillonite.

18. The method according to any one of claims 1 to 17, characterized in that the washing and / or cleaning active substance cannot pass through the semipermeable membrane or at least diffuses through the semipermeable membrane by at least an order of magnitude slower than water molecules.

19. The method according to any one of claims 1 to 18, characterized in that the washing and / or cleaning active substance is selected from the group of washing and / or cleaning active inorganic and organic acids, in particular carboxylic acids, soil repellent and soil Release agents, bleaching agents such as hypochlorites, washing and cleaning-active enzymatic systems and enzymes such as amylases, cellulases, lipases and proteases, fragrances, in particular perfume oils, antimicrobial agents, in particular antibacterial, antiviral and / or fungicidal agents, graying and discoloration inhibitors, active substances Color protection, substances and additives for laundry care, surfactants, in particular surfactants with fabric softener properties, as well as pH adjusting agents and pH buffer substances.

20. The method according to any one of claims 1 to 19, characterized in that the washing and / or cleaning active substance is inert to the capsule shell material.

21. The method according to any one of claims 1 to 20, characterized in that the further ingredient cannot pass through the semipermeable capsule shell (membrane) or at least diffuses through the semipermeable membrane by at least an order of magnitude slower than water molecules.

22. The method according to any one of claims 1 to 21, characterized in that the further ingredient is inert to the capsule shell material and preferably has no surfactant properties.

23. The method according to any one of claims 1 to 22, characterized in that the further ingredient builds up an osmotic pressure inside the capsule when diluted, in particular with water.

24. The method according to any one of claims 1 to 23, characterized in that the further ingredient is selected in particular from the group of alcohols, glycols, in particular polyethylene and polypropylene glycols, ionic and polar compounds, inorganic and organic salts and sugars of all kinds.

25. The method according to any one of claims 1 to 24, characterized in that the washing and / or cleaning active substance and / or the further ingredient are embedded or embedded in a matrix-forming material which is completely enclosed by the semipermeable capsule shell (membrane).

26. The method according to any one of claims 1 to 25, characterized in that the matrix-forming material is selected from the group of pectins, agar agar, xanthan gum, guar gum, gelatins, gel formers, polyvinyl alcohols (PVAI), gellan gum, carrageenan , Starch derivatives and polysaccharides.

27. The method according to any one of claims 1 to 26, characterized in that the matrix-forming material is additionally crosslinked, in particular by polyvalent metal ions such as alkaline earth metal ions or else by boric acid or glutaraldehyde.

28. The method according to any one of claims 1 to 27, characterized in that the semipermeable capsule shell (membrane) permeable to water molecules is impermeable or at least one order of magnitude slower than diffusion of water molecules for the wash and / or cleaning active substance and preferably also impermeable or at least one order of magnitude slower compared to water molecules can be passed through diffusion for the possibly present further ingredient and any matrix-forming material present.

29. The method according to any one of claims 1 to 28, characterized in that the microcapsules have average diameters of 1 to 5,000 microns, in particular 50 to 3,000 microns, preferably 100 to 2,000 microns.

30. The method according to any one of claims 1 to 29, characterized in that the complexation reaction preferably proceeds spontaneously.

31. The method according to any one of claims 1 to 30, characterized in that the method is carried out at temperatures from 0 to 100 ° C, in particular 20 to 60 ° C, preferably at room temperature.

32. The method according to any one of claims 1 to 31, characterized in that the method is carried out at reduced, elevated or normal pressure, preferably at normal pressure.

33. The method according to any one of claims 1 to 32, characterized in that the method is carried out at pH values from 0 to 10, in particular from 1 to 6.

34. The method according to any one of claims 1 to 33, characterized in that the microcapsules 1 to 99 wt .-%, in particular 1 to 60 wt .-%, preferably 2 to 50 wt .-%, the washing and / or cleaning active Contain substance, based on the total weight of the microcapsules.

35. The method according to any one of claims 1 to 34, characterized in that the microcapsules contain 1 to 99% by weight, in particular 1 to 60% by weight, preferably 2 to 50% by weight, of the further ingredient, based on the total weight of the microcapsules.

36. The method according to any one of claims 1 to 35, characterized in that the microcapsules 0.1 to 50 wt .-%, in particular 0.5 to 30 wt .-%, preferably 0.5 to 10 wt .-%, of Contain matrix-forming material, based on the total weight of the microcapsules.

37. Microcapsules obtainable by the process according to one of claims 1 to 36.

38. Microcapsules with a semipermeable capsule shell (membrane) which, in addition to water, contain at least one washing and / or cleaning active substance and optionally at least one further ingredient in the interior of the capsule, the washing and / or cleaning active substance and optionally the further ingredient in a matrix-forming material can be stored, characterized in that the semipermeable capsule shell (membrane) comprises a polyelectrolyte complex and the shell consists of at least one layer of such polyelectrolyte complexes, the semipermeable membrane being permeable to water molecules and to the encapsulated detergent and / or cleaning substances and preferably also impermeable to the other ingredient and the matrix-forming material or at least one order of magnitude slower than water molecules can be passed through diffusion, so that when the microcapsules are introduced into egg ne aqueous phase inside the capsule can build up an osmotic pressure which causes the capsules to burst.

39. Microcapsules according to claim 37 or 38, characterized by an average capsule diameter of 1 to 5,000 microns, in particular 50 to 3,000 microns, preferably 100 to 2,000 microns.

40. Microcapsules according to one of claims 37 to 39, characterized in that the microcapsules 1 to 99 wt .-%, in particular 1 to 60 wt .-%, preferably 2 to 50 wt .-%, of the washing and / or cleaning active Contain substance, based on the total weight of the microcapsules.

41. Microcapsules according to one of claims 37 to 40, characterized in that the microcapsules contain 1 to 99% by weight, in particular 1 to 60% by weight, preferably 2 to 50% by weight, of the further ingredient, based on the total weight of the microcapsules.

42. Microcapsules according to one of claims 37 to 41, characterized in that the microcapsules 0.1 to 50 wt .-%, in particular 0.5 to 30 wt .-%, preferably 0.5 to 10 wt .-%, of Contain matrix-forming material, based on the total weight of the microcapsules.

43. Use of the microcapsules according to claims 37 to 42 as constituents of washing and cleaning agents, in particular liquid washing and cleaning agents, fabric softeners and post-washing agents, cosmetic products and products for personal care.

44. Use of the microcapsules according to claims 37 to 42 as an osmosis-controlled metering system, in particular for use in detergents and cleaning agents, in particular liquid detergents and cleaning agents, fabric softeners and laundry aftertreatment agents.

45. Washing and cleaning agents, in particular liquid washing and cleaning agents, fabric softeners or laundry aftertreatment agents, containing microcapsules according to claims 37 to 42.

46. Detergent and cleaning agent according to claim 44, containing microcapsules according to claims 37 to 42 in amounts of 0.01 to 30% by weight, in particular 0.1 to 20% by weight, preferably 1 to 10% by weight.