CA1266003A - Stick antiperspirants - Google Patents

Abstract

ABSTRACT

STICK ANTIPERSPIRANTS

Antiperspirant stick compositions comprising:
(a) from about 35% to about 60% of a volatile silicone oil:
(b) from about 1% to about 10% of a non-volatile emollient;
(c) from about 3% to about 5% of a high melting point wax;
(d) from about 10% to about 18% of a low melting point wax:
(e) from about 0.3% to about 3.0% of a colloidal silica mate-rial; and (f) from about 15% to about 50% of a particulate antiper-spirant material;
wherein the composition contains no more than about 2% of particulate materials other than the colloidal silica material and the particulate antiperspirant material.

Description

STICK ANTIPERSPIRANTS
John Paul Luebbe BACKGF<OUND OF THE INVENTION
The present invention relates to antiperspirant compositions in solid stick form. More particularly, it relates to antiperspirant sticks with improved cosmetic characteristics.
Many solid antiperspirant compositions are described in the chemical and cosmetic literature. In ~eneral, there are three types of such antiperspirant stick formulations: compressed powder sticks, gel sticks and wax sticks. While each of these formulation types may have advantages in certain situations, each also has disadvantages. For example, compressed powder sticks are often brittle and hard, and leave a cosmetically-unacceptable dust upon application. Gels may be unstable due to evaporation of alcohol and ~more importantly) due to interaction of astringent metal salts with the soaps used in the sticks. Wax-based formu-lations can also yield cosmetically-unacceptable products due to such factors as hardness, greasiness and stickir,ess.
Nevertheless, the increased stability and antiperspirant efficacy afforded by wax-based formulations has resulted in such sticks being generally preferred for antiperspirant stick products.
The use of a wide variety of materials is described in the literature in order to optimize the cosmetic characteristics of antiperspirant wax-based sticks . For example, U . S. Patent 4,126,S79, Davy, et al., issued November 21, 1978, describes antiperspirant sticks containing volatile silicone oils, long-chain fatty alcohols, and a powdered material (such as an antiperspirant active, fumed silica, talc or sodium bicarbonate~ for stable sticks with good glide properties. U.S. Patent 4,280,994, Turney, issued July 28, 1981, claims antiperspirant sticks containing volatile silicone, a waxy material and polyethylene glycol, in order to ease application of the composition. British Patent Application

2,139,496, Geria, published November 14, 1984, describes the use of a water-soluble emollient in order to avoid the waxy feel of a wax-based antiperspirant stick. European Patent Publication 117,070, May, published August 29, 1984, describes wax-based antiperspirant sticks containing certain fatty alcohols in order to increase produc~ stability.
While many stick formulations described in the literature may have certain desirable characteristics, such as acceptable product 5 hardness and stability, or pleasing aesthetics or application characteristics, or good in-use characteristics, these formulations ~o npt provide optimal overall performance. Thus, sticks that have good "glide" or other good application characteristics may, however, have poor stability and may be too s~ft. Conversely, 10 sticks which are dimensionally stable and of adequate hardness may impart a waxy feel and have poor application cosmetics.
Furthermore, tt e wax-based sticks described in the literature typically produce high levels of visible residue which is aesthetically unappealing and may leave visible soil on clothin~.
It is now been discovered that wax-based antiperspirant sticks contair~ing selected emollients, fillers, and waxes have ~ood compositional stability as well as good application and in-use cosmetic characteristics. In partic~lar, the compositions of the present invention leave lower levels o~ visible residue, and have 20 improved "glide" and other application cosmetics, while main-taining good product stability and hardness.
SUMlvIARY OF THE INVENTION
. .
The present invention provides antiperspirant stick 25 compositions comprising: (a) from about 35% to about 60%
of a volatile silicone oil; (b) from about 1% to about 10% of a non-volatile emollient selected from the group consisting of water-insoluble ethers, polyoranosiloxanes, and mixtures thereof; (c) from about 3~ to about 5% of a high melting point wax; (d) from about 10% to about 18% of a low melting point wax selected from the group consisting of stearyl alcohol, cetyl alcohol, and mixtures thereof;
(e) from about ~.3~ to about 1.5% of a fumed colloidal silica material; and (f) from about 15~ to about 50% of a particulate antiperspirant active; wherein said compo-sition is essentially free of particulate materials other than said fumed colloidal silica material and said particulate antiperspirant material.

6~

DESCRIPTION OF THE iNVENTlON
The antiperspirant sticks of this invention contain five essential ingredients: a volatile silicone oil, a non-volatile emollient, a high melting point wax, a low melting point wax, a colloidal silica material, and an antiperspirant active. These compositions (herein "antiperspirant sticks") encompass any solid ~or semi-solid) composition intended for human use in order to deposit an~iperspirant material on human ~issue. The essential and optional components to be included in the present 10 antiperspirant sticks must be "cosmetically-acceptable", i.e., safe for human use and aesthetically acceptable as the levels at which such materials are used in the present compositions, at a reason-able ri~k/benefit ratio.
Specifically, the antiperspirant sticks of the present 15 invention comprise:
(a) from about 359~ to about 60% of a volatile silicone oil;
(b) from about 1~ to about 10% of a non-volatile emollient;
lc) from about 3~ to about 5~ of a hi~h melting point wax;
(d) from about 10% to about lS% of a low melting point wax;
(e) from about 0.3~ to about 3.û% of a colloidal silica material: and (f) from about 15g6 to about 50% of a particulate antiper-spirant material;
wherein said composition contains no more than about 2~ of 25 particulate materials other than said colloidal silica material and said particulate antiperspirant material. ~AII percentages herein are by weight of total composition. ) Preferably, the present antiperspirant sticks contain from about 40% to about 55~ of the volatile silicone oils. The - 30 non-volatile emollients are preferably present at a level of from about 1 . 54 to about 8%, more preferably from about 2 . 5~ to about 6.5~. The high melting point wax is preferably present at a level of about 4%, and the low melting point wax preferably present at a level of from about 11~ to about 15~. Preferably, the colloidal 35 silica material is present at a level of from about 0. 4~ to about 1.0%, more preferably from about 0.4~ to about 0.8~. The antiperspirant material is preferably incorporated a~ a level of from about 15~ to about 40%, more preferably from about 20~ to about 40%. Also preferably, the present compositions ere substantially anhycirous, i.e., containing less than about 2~ of free lchemically unboundl water.
The compositions of this invention are made by well-established methods that are known in the art. Care should be taken in the processes of making these compositions so as to maintain uniform distribution of particulate materials throughout the antiperspirant sticks. Specific essential and non-essential materials to be included, and their levels, are selected in order to produce a stick of desired hardness, so as to maintain dimensional stability while depositing a suitable amount of antiperspirant material on ~he skin during normal use. Hardness of sticks can be determineci by a variety of methods, including American Society for T~sting and Materials (ASTM) Method D-5.
This method involves the use of a needle or polished cone of particular weight and dimension, which is allowed to travel downward through the stick material for a pre-determined period of time. The distance traveled by the needle or cone is a rela-tive measure of the stick hardness. Utilizing Method D-5, with a #1554 penetration needle (manufactured by Sergeant-Welch Scientific Company) weighing 50 grams, and a Precision Model 73515 Penetrometer (manufactureci by Precision Scientific, subsidiary of GCA Corporation), the antiperspirant sticks of the present invention preferably yleld a penetration of from about 60 to about 150 niilimeters, more preferably from about 80 to about 150 millimeters, over a period of 5 seconds.
Essential Components Volatile Silicone Oil:
The antiperspirant sticks of this invention contain a volatile polyorganosiloxane, which mày function as a liquid emollient. lAs used herein, "volatile" refers to those materials which have a measuralle vapor pressure at ambient conditions. ~ The volatile polyorganosiloxanes useful herein may be cyclic or linear. A
description of various volatile silicones is found in Todd, et ai., "Volatile Silicone Fluids for Cosmetics", Cosmetics and Toiletries, ~6~

91, 27 - 32 (1976), Preferred cyclic silicones include polydimethylsiloxanes containing from about

3 to about 9 silicon atoms, preferably containing from about 4 to about 5 silicon atoms. Preferred linear silicone oils include the 5 polydimethylsiloxanes containing from about 3 to about 9 silicon atoms. The linear volatile silicones generally have viscosities of less than about 5 centistokes at 25C., while the cyclic materials have viscosities of less than about l O centistokes . Examples of silicone oils useful in the present invention include: Dow Corning l O 344, Dow Corning 345, and Dow Cornin~ 200 (manufactured by the Dow Corning Corporation); Silicone 7207 and Silicone 7158 (manufactured by the Union Carbide Corporatlon); SF1202 (manufactured by General Electric); and SWS-03314 (manufactured by Stouffer Chemicat).
15 Non-voiati le Emol I ient:
The present antiperspirant sticks contain one or more non-volatile emollients. Such materials include fatty acid and fatty alcohol esters, water-insoluble ethers and alcohols, polyorgano-siloxanes, and mixtures thereof. Water-insoluble ethers are 20 particularly preferred non-volatile emollient materials, including polypropylene glycol and the eondensation products of an alkylene oxide with an alcohol. A particularly preferred water-insoluble ether is the condensation product of about 14 moles of propylene oxide with one mole of butyi alcohol, sold as Fluid APR by Union 25 Carbide C:orporation. Emollients among those useful herein are described in 1 Cosmetics, Science and Techno!ogy 27-104 ~M.
Balsam and E. Sagarin ed. 1972~, and U.S. Patent 4,202,879, Shelton, issued May 13, 1980, The present compositions also preferably contain a non-30 volatile slticone oil as an emollient material. Such silicone oils include polyalkysiloxanes, polyalkyarylsiloxanes, and polyether-siloxane copolymers. The essentially non-volatile polyalkyl siloxanes useful herein include, for example, polydimethyl siloxanes with viscosities of from about 5 to about 100, 000 35 centistokes at 25C. Among the preferred non-volatile emollients useful in the present composition are the polydimethyl siloxanes ;~

having viscosities from about 10 to about 400 centistokes at 25C.
Such polyalkyl siloxanes include the Vicasil series (sold by General Electric Company) and the Dow Corning 200 series (sold by Dow Corning Corporation ) . Polyalkylaryl siloxanes include poly methylphenyl siloxanes having viscosities of from about 15 to about 65 centistokes at 25C. These are available, for example, as SF 1075 methylphenyl fluid (sold by General Electric Company) and 556 Cosmetic Grade Fluid (sold by Dow Corning Corporation).
Useful polyether siloxane copolymers include, for example, a l O polyoxyalkylene ether copolymer having a viscosity of about 1200 to 1500 centistokes at 25C. Such a fluid is available as SF-1066 organosilicone surfactant (sold by General Electric Companyl.
Polysiloxane ethylene glycol ether copolymers are preferred copolymers for use in the present compositions.
Hiclh Meltin~ Point Wax:
The antiperspirant sticks of the present invention contain one or more materials having wax-like characteristics and having a melting point of from about 65C to about 1 02C . Such waxes include beeswax, spermaceti, carnauba, baysberry, candelilla, montan, ozokerite, ceresin, paraffin, hydrogenated castor oil (castor wax), synthetic ~axes such as Fisher-Tropsch waxes, microcrystalline wax, and mixtures thereof. Castor wax is a preferred high-melting point wax useful herein. Such high-melting point waxes among those useful herein are disclosed in U.S. Pa~ent 4,049,792, Elsnau, issued Sep~ember 20, 1977 Low Meltina Point Wax:
The present antiperspirant sticks contain ~ax-like materials having a low melting point, i.e., having a melting point of from about 37C to about 75C. Such materials include fatty acids, fatty alcohols, fatty acid esters and fatty acid amides, having fatty chains of from about 8 to about 30 carbon atoms, preferably from about 12 to about 18 carbon atoms, and mixtures thereof.
Preferred low melting point waxes include cetyl alcohol, palmitic acid, myristyl a/cohol, stearyl alcohol, paraffin, and mixtures ,~ , ~3 thereof. Stearyl alcohol, cetyl alcohol, and mixtures thereof are particularly preferred.
Colloidal Silica Material:
.
The present antiperspirant sticks contain a finely divided 5 silica material. Preferably, the silica material used in the present cornpositions is a fumed silica, present at a level of from about 0.3~ to about 1.5~. Fumed silicas can generally be described as fluffy, white, superfine powders of extremely low bulk density but having high surface areas. These fumed silicas are typically 10 made by a vapor phase process that produces colloidal silica by the hydrolysis of silicon tetrachloride at a very high temperature.
These materials consist of about 99. 8~ silicon dioxide by weight (on a moisture free basis), existing in three dimensional branched chain aggregates, with a surface that is hydrophilic and capable 15 of hydrogen bonding. Such siilcas have surface areas ranging from about 2.5 to about 1,200 square meters per gram. Colloidal silica materials are described in Hardy, et al., "The Use of Fumed Silica in Cosmetics", 2 Cosmetic Technolo~y 35 ( 1980) _ _ and R. Iler, The ~f 20 Siiica (1979).
Colloidal silica materials useful herein are available from a variety of sources, including Syloid silicas (manufactured by Davison Chemical Division of W. F~o Grace), Cab-O-Sil (manufac-tured by Cabot Corporation), and Aerosil (manufactured by 25 Degussa A.G. ) . Cab-O-Sil is a particularly preferred commercially available colloidal silica useful herein, with surface areas ranging from about 200 to about 400 square meters per gram.
P iculate AntieersE~rant Materia!:
The particulate antiperspirant materials of this invention comprise any compound or compositlon having antiperspirant actlvity. Astringent metallic salts are preferrPd antiperspirant materials for use herein, particularly including the inorganic and organic salts of aluminum, zirconium and ~inc, and mixtures 35 thereof. Particularly preferred are the aluminum and zirconium salts such as aluminum halides, aluminum hydroxide halides, .~ ' .

~_ - R -zirconyl oxide halides, zirconyl hydroxy halides, and mixtures thereof .
Preferred aluminum salts include those of the formula A12 ( OH )aCIb Xt~2 s wherein a is from about 2 to about 5; a~b = 6; x is from about 1 to about 6; and wherein a, b, and x may have non-integer values. Particularly preferred are aluminum chlorhydroxides referred to as "5/6 basic chlorhydroxide", wherein a = 5, and "2/3 basic chlorhydroxide, " wherein a = 4. Processes for prepar-10 ing aluminum salts are disclosed in the following documents:
U . S . Patent 3, 887, 692, Gilman, issued June 3, 1975; U.S. Patent 3,904,741, Jones et al., issued September 9, 1975; U.S. Patent 4,359,456, Cosling, et al., issued November 16, 1982; and British Patent Specification 2,048,229, Fitzgerald, et al., published December 10, 1980.
Mlxtures of aluminum salts are described in British Pa~ent Specification 1,347,950, Shin, et al., published February 27, 1974 Zirconium salts are also preferred for use in antiperspirant sticks of the present invention. Such salts are of the general 20 formula ZrO(OH )2_aCla xH2O
wherein a is from about 1. 5 to about 1 . 87; x is frorr, about 1 to about 7; and wherein a and n may have non-inte~er values.
These zirconium salts are disclosed in Belgium Patent 825,146, 25 Schmitz, issued August 4, 1975.
Particularly preferred zirconium salts are those complexes also containing aluminum and glycine, commonly known as "ZAG complexes". Such ZAG complexes contain aluminum chlorhydroxide and zirconyl hydroxychloride of the formulae d~tailed above. These compounds in ZAC complexes are disclosed in U.S. Pa~ent 3,679,068, Luedders, et al., issued February 12, 1974, and U.S. Patent 4,120,948, Shelton, issued October 17, 1978.

;
i )3 g Partic~1ar1y preferred antiperspirant materia1s are described in concurrently f iled Canadian Patent Application Seria1 No. 505,640. Such particulate antiperspirant actives, yièlding lower levels of visible residue, contain at least 80% of the particles with a diameter ~reater than about 10 microns, and at least about 75%
of the antlperspIrant materlal partlcles wlth a dlameter yreater than abou. 16 microns. Preferably, at least about 80~, more preferably at least about g0% of the antiperspirant particles, have a diameter greater than about 16 microns.
~e~
The compositions of the present invention may also contain optional components which modify the physical characteristics of the vehicles or serve as "active" components when deposited on the sk~n in additlon ~o the particulate antiperspirant material.
Additional active components include bacteriostats and fungistats.
Optional components useful herein are described in thP following documents: U.S. Patent 4,049,792, Elsnau, issued September 20, 1~77; Canadian Patent 1,164,347, Beckmeyer, et al., issued March 27, 1984; European Patent SpeciEication 117,070, May, published August 29, 1985;
Canadian Patent Application Serial Number 497,958, McCall, filed December 18, 1985; and Geria, "Formulatic,n of Stick Antiperspirants and Deodorants, " 99 Cosmet1cs & To11etrles 55-60 (1984) .
The particuIar non-active components that may be useful will depend upon the form of application that is desired. 5uch com-ponents include, for example, emollients, colorants, perfumes, and emulsifiers. Althou~h the present compositions may also contain fillers and other particulate materials other than the particulate active and colloidal silica materials described above, such particulates may adversely affect the perceived residue benefits of the present Invention. (As used herein, "particulate materials" are those materials that neither dissolve in the composition components, nor melt during manufacture of the stick. ) Preferably, then, the present compositions contain a total 6~

level of particulate materials, other than the particulate antiperspirant materials and the colioidal silica materials, less than about 2~. More preferably, the present compositions are essentially free from particulate materials other than the 5 particulate antiperspirant active and the colloidal silica material.
The following non-limitiny examples illustrate the composi-tions, processes and uses of the present invention.
EXAMPLE I
A stick antiperspirant composition, accordiny to the present 10 invention, was made with the following components:
Components % by weight cyclomethicone 45. 75 MacrosphericalTM - RE5011 30,50 stearyl alcohol 12 . ûO
15 Fluid Ap2 5.00 dimethicone (350 cs viscosity) 1.50 castor wax 4.00 Cab-O-Sil H S-53 û . 75 PEG-8 distearate 0.50 1: 5/5 basic aluminum chlorhydroxide particulate antiperspirant material, sold by Reheis Chemical Company, with approximately ~7.5% of the particles having a diameter of greater than 10 microns and approximately 92~ greater than 16 microns water insoluble ether, condensation product of about 14 moles propylene oxide with one mole butyl alcohol, sold by Union Carbide Corporation 3: colloidal silica material, sold by Cabot Corporation, having a surface area of approximately 325 m per gram, and a nominal particle size of 0.008 microns.
The cyclomethicone, dimethicone and Fluid AP were mixed and heated to about 82C. The stearyl alcohol, castor wax and PEG-8 distearate were then added, and the temperature main-tained at about 82C until the waxes dissolved. The Cab-O-Sil was then added ancl the mixture heated to about 93C and the 35 antiperspirant active was added. Stirring was continued and the ~2~ 3 batch cooled to approximately 56C and poured into stick forms.
Solid antiperspirant sticks were obtained upon cooling below 48C.
An antiperspirant stick, as formulated above, was applied to the underarm of a human subject reducing the perspiration in the 5 applied area~ In the above example, cetyl alcohol is substituted for stearyl alcohol, with substantially similar results. Also, in the above example, dimethicone (100 cs viscosity) is substituted for dimethicone (350 cs viscosity), with substantially similar results .
EXAMPLE I !
A stick antiperspirant composition, according to the present invention, is made with the following components:
Component_ %_by wei~
cyclomethicone 49 . 80 Rezal 36GP active* 26.70 stearyl alcohol 12 . 00 Fluid AP 6 . 50 castor wax 4.00 PEG-8 distearate 0. 50 Cab-O-Sil 0.50 *: zirconium-aluminum-glycine hydroxychloride complex antiperspirant active, sold by Reheis Chemical Company An antiperspirant stick is made in a manner similar to that described in Example 1. The product, when applied to the 25 underarm of a human subject, is effective as an antiperspirant.

EXAMPLE l l l A stick antiperspirant composition, according to the present invention, is made with the following components:
(::omponents ~ by weight cyclomethicone 44.30 MacrosphericalTM-95l 30 50 cetyl alcohol 6. 00 stearyl alcohol ~, oo Fluid AP 4.00 dimethicone (350 cs ~ 2 . 50 ~2~ 3 castor wax 4.20 Syloid 722 2 . 50 1 S/6 basic aluminum chlorhydrate par~iculate antiperspirant material, sold by Reheis Chemical Company, with approximately 5 98~ of the particles having a diameter greater than 10 microns and approximately 96~ greater than 16 microns ~: colloidal silica material, sold by Davison Chemical l)ivision of W. R. Grace, having a surface area of approximately 340 m2 per gram and a nominal particle size of 4 microns.
An antiperspirant stick is made in a manner similar to that described in Example i. The product, when applied to the underarm of a human subject, is effective as an antiperspirant.

Claims (9)

Claims:

1. An antiperspirant stick composition comprising:
(a) from about 35% to about 60% of a volatile silicone oil;
(b) from about 1% to about 10% of a non-volatile emollient selected from the group consisting of water-insoluble ethers, polyoranosiloxanes, and mixtures thereof;
(c) from about 3% to about 5% of a high melting point wax;
(d) from about 10% to about 18% of a low melting point wax selected from the group consisting of stearyl alcohol, cetyl alcohol, and mixtures thereof;
(e) from about 0.3% to about 1.5% of a fumed colloidal silica material; and (f) from about 15% to about 50% of a particulate antiperspirant active;
wherein said composition is essentially free of particulate materials other than said fumed colloidal silica material and said particulate antiperspirant material.

2. An antiperspirant stick composition, according to Claim 1, wherein said fumed colloidal silica material is present at a level of from about 0.4% to about 1.0%.

3. An antiperspirant stick composition according to Claim 1, wherein said non-volatile emollient is present at a level of from about 2.5% to about 6.5%.

4. An antiperspirant stick composition, according to Claim 1, wherein said non-volatile emollient is a mixture of a water-soluble ether and a polyorganosiloxane.

5. An antiperspirant stick composition, according to Claim 1, wherein said high melting point wax is castor wax.

6. An antiperspirant stick composition, according to Claim 5, wherein said high melting point wax is present at a level of about 4%.

7. An antiperspirant stick composition, according to Claim 1, comprising from about 40% to about 55% of said volatile silicone oil, from about 11% to about 15% of said low melting point wax, and from about 15% to about 40% of said particulate antiperspirant material.

8. An antiperspirant stick composition, according to Claim 7, wherein said particulate antiperspirant material contains at least 80% of the particles with a diameter greater than about 10 microns, and at least 75% of the antiperspirant particles with a diameter greater than about 16 microns.

9. An antiperspirant stick composition comprising:
(a) from about 40% to about 55% of a volatile silicone oil;
(b) from about 2.5% to about 6.5% of a non-volatile emollient;
(c) from about 3% to about 5% of castor wax;
(d) from about 11% to about 15% of a low melting point wax selected from the group consisting of stearyl alcohol, cetyl alcohol, and mixtures thereof;
(e) from about 0.4% to about 1.0% of a fumed colloidal silica material, and (f) from about 15% to about 40% of a particulate antiperspirant material;
wherein said composition is essentially free of particulate materials other than said fumed colloidal silica material and said particulate antiperspirant material.