GB1563301A - Antiperspirant compositions for application to the skin from pump-spray or roll-on applicators - Google Patents

Abstract

The composition is intended to be applied to the skin from a pump spray applicator or a roll-on applicator and consists of a liquid, propellant-free medium which contains A) 40 to 85% by weight, based on the total weight of the composition, of an alcohol, B) 5 to 25% by weight, based on the total weight of the composition, of an aluminium chlorhydroxide complex dissolved in the alcohol, and C) dissolved in the composition a) 5 to 40% by weight, based on the total weight of the composition, of a cyclic polydimethylsiloxane of the formula I <IMAGE> or b) 1 to 10% by weight, based on the total weight of the composition, of a non-volatile polyphenylmethylsiloxane or of a poly-higher-alkylsiloxane in which each alkyl radical has at least three carbon atoms. The composition is highly effective in respect of adhesion to the skin and reduction or virtual elimination of the problems of antiperspirants supplied in powder form, namely dusting and lack of adhesion to the skin. In addition, the composition has the advantage that it considerably reduces the stickiness of alcoholic solutions of the aluminium complexes.

Description

(54) ANTIPERSPIRANT COMPOSITIONS FOR APPLICATION TO THE SKIN FROM PUMP-SPRAY OR ROLL-ON APPLICATORS (71) We, UNILEVER LIMITED, a company organised under the laws of Great Britain, of Unilever House, Blackfriars, London, E.C.4., England, do hereby declare the invention for which we pray that a patent may be granted to us and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to skin compositions and more particularly to liquid antiperspirant compositions which are particularly suitable for application to the skin from a pump spray or roll-on applicator: and to antiperspirant products comprising such applicators charged with the compositions.

Antiperspirant compositions have been manufactured in varying forms and such products as creams, lotions, roll-ons, gel sticks, and aqueous solutions to be applied by a pad, have been known for many years, for example, a liquid antiperspirant composidon is disclosed in U.S. Patent Specification No. 2,955,983.

In more recent years a more convenient form of application of an antiperspirant has been developed. This is a pressurised antiperspirant system where the product is dispensed as a fine spray, as exemplified in U.S. Patent Specification No.

3,798,317. Several additional U.S. patent specifications of interest in the antiperspirant art are as follows: Nos. 2,955,983; 3,359,169; 3,420,932; 3,509,253; 3,816,613; 3,863,005 and 3,873,686. Basically, the forum of these aerosol products has developed as either a composition having an antiperspirant active agent suspended as a dry impalpable powder in a non-aqueous carrier vehicle or as a composition in which the active antiperspirant agent is dissolved in an alcoholic medium. Both of these compositions are dispensed from an aerosol container through a valve by the action of a propellant. The suspension of impalpable powder has achieved much greater use than the solution. One reason for this is that the suspension has proved to be much less corrosive to appropriately constructed cans. It is more important to consumer acceptance, however, that the product from the suspension in the propellant as it reaches the skin is in a form which contains little volatile material and therefore feels dry, com- fortable, non-tacky and smooth. Alcoholic systems utilising a solution rather than a suspension feel smooth and non-tacky when dry but are deposited in a wet tacky state. Nonetheless, the latter products, i.e. the alcoholic systems utilising a solution, enjoy a significant degree of consumer acceptance in the marketplace.

A major problem of aerosols in general, and of suspension products in particular, has been that as applied they cause a strong dusting and billowing of the spray, especially when the amount of liquid carrier vehicle is reduced in order to minimise clothing staining potential of the formulation. In some instances, this dusting can be unpleasant to the user of the product and at best makes for less efficacious application of the product than is desirable.

Roll-on antiperspirants while not having some of the problems of pressurised aerosol sprays do, however, have their own specific drawbacks. These drawbacks are usually esthetic. In order words, a roll-on antiperspirant will normally be used by only one person because it comes in contact with the underarm and multiple usership is not desirable either esthetically or hygienically. Roll-on antiperspirants usually comprise an aqueous-alcoholic solution of aluminium chlorhydroxide. Frequently these solutions during drying are very tacky to the touch. Also, the product takes a relatively long time to dry, and may leave an oily residue on the skin due to the oily material (lubricant) required to ensure free functioning of the roll ball. Additionally, this lubricant also acts as an emollient.

Because there are many problems related to aerosol antiperspirant, it becomes advantageous to investigate other methods of applying antiperspirant compositions which eliminate a propellant system and additionally eliminate the billowing problem which is attendant on the use of the finely divided aerosol pressurised sprays.

Accordingly, it is an object of the prevent invention to provide an antiperspirant composition suitable for applying to the skin from a pump spray or roll-on applicator which composition is relatively non-tacky during drying.

According to the invention there is provided an antiperspirant composition suitable for applying to the skin from a pump spray applicator or a roll-on applicator consisting of a liquid medium comprising: A. 40 to 86 ", by weight of the composition of a volatile cosmetically acceptable alcohol; B. 5 to 25% by weight of the composition of an alcohol-soluble aluminium chlorhydroxide complex dissolved in said alcohol; and C. a liquid siloxane dissolved in the composition comprising (a) 5 to 40% by weight of the composition of a cyclic poly(dimethylsiloxane) of the structural formula:

or (b) 1 to 10% by weight of the composition of a non-volatile poly(phenyl methylsiloxane) or a poly(higher alkyl siloxane) wherein each alkyl group contains at least three carbon atoms; the composition being free of pressurising propellant material.

Preferred compositions of the invention are those containing the cyclic polydimethylsiloxane since an additional benefit imparted by this material is that it gives the perception of quick drying. In such preferred compositions it is advantageous to include from 0.5 to 10% by weight of the antiperspirant composition a poly(alkylsiloxane), poly(alkylarylsiloxane) or polyether siloxane copolymer. Such an addition provides lubricity to the formulation and acts to inhibit malfunction of a pump spray or roll-on applicator.

The compositions of this invention are highly effective in adhering to the skin and in reducing or substantially eliminating the problems of antiperspirants dispensed in powdered forms, namely dusting and lack of good adhesion to the skin. Additionally, these compositions provide the advantage of substantially reducing the tackiness of alcohol solutions of the aluminium complexes.

The alcohol soluble aluminium chlorhydroxide complex which is employed in the antiperspirant composition of this invention is preferably a 1,2-propylene glycol complex of aluminium chlorhydroxide. The preparation of this complex is described in U.S. Patent 3,420,932. The preferred 1,2-propylene glycol derivative as described in the above-mentioned patent having the formula Ah(H )u ,- (OH) szs l(Cl)o -l 1(12- propylene glycol),,7 l 3 is marketed as a powder under the Reheis Chemical Company trademark "Rehydrol". Other alcohol soluble forms of aluminium chlorhydroxide may also be utilised. The amount of the complex preferably employed is from about 10% to about 20% by weight.

The compositions of the invention are preferably essentially anhydrous, i.e. contain no water added as such. However, a minor proportion of water may be tolerated insofar as it still allows the aluminium chlorhydroxide complex and siloxane to remain in solution or otherwise does not adversely affect the stability of the composition. It has the disadvantage, however, of slowing the rate of drying of the product. Therefore, the composition should be substantially anhydrous, i.e. contain not more than 20% by weight of water and preferably not more than 5 VÓ by weight, i.e. preferably less.

The alcohol used is preferably essentially anhydrous ethanol and denatured ethanol meeting this criterion, and which is also cosmetically acceptable, is of course appropriate. Other short chain cosmetically acceptable alcohols such as for example isopropanol may also be utilised but the characteristic odour makes these other alcohols less desirable. The amount of alcohol required is from about 40 to about 85% by weight of the total composition, preferably from about 60 to 80% by weight. The lower limit is dictated by the requirement of solubility of the other components of the mixture. If less than about 400' is used, difficulty is encountered in dissolving the other components and in attaining a solution of the proper flow characteristics for pump spray or roll-ball action. If more than about 85 b is used, the amount of the other components is too low to effectively perform their functions. 65 to 80% represents the most preferable range to achieve good solubility together with acceptable efficacy.

The antiperspirant composition of the invention preferably has incorporated therein a gel inhibitor in an amount sufficient to substantially reduce gelling thereof upon extended ageing, especially at elevated temperature. Suitable gelling agents for alcoholic solutions of alcohol soluble complexes of aluminium chlorhydroxide are known to those in the art. Triple pressed stearic acid, which is a combination of about 50% by weight stearic acid with about 50% by weight myristic acid, has been found to be preferable to satisfactorily inhibit gelling of the composition. Other suitable inhibitors include for example isostearic acid, propylene glycol, oleyl alcohol, hexadecyl alcohol, oleyl ether phosphate, and combinations and mixtures thereof. The amount of the anti-gelling agent when used is desirably from about 0.5% by weight to about 5% by weight of the total composition and preferably from about 1% to about 3.5%, which amount is particularly effective to achieve a free flowing composition.

Optional antiperspirant agents in amounts up to 10% by weight of the composition that may be included in the composition are aluminium chloride, zirconyl oxychloride and basic aluminium bromide as well as other agents known in the art; see for example U.S. Patent 2,906,668. The use of these agents will, of course, depend on their compatibility in the system, which compatibility can be evaluated by simple empirical methods.

Adjuvants that may be used include for example emollients such as isopropyl myristate, propylene glycol monoisostearate, isopropyl palmitate, and ethoxylated lanolin Perfume is also optionally added. These adjuvants must be compatible with the other components of the system and must not leave a residue which substantially interferes with efficacy. Generally, these adjuvants or additives, when present, are included in an amount up to about 10% by weight of the composition.

The cyclic poly(dimethylsiloxane) of the formula

when prepared commercially, may contain small amounts of the less volatile corresponding 10 membered ring structure. This 10 membered compound, while less volatile than the 8 membered compound shown, does not interfere with the functioning of the 8 membered ring structure and has utility in itself. This cyclic 8 membered ring poly(dimethylsiloxane) is relatively volatile and has been found to reduce or substantially eliminate tackiness of the composition when added in the proportions given above, as well as to enhance the perception of fast drying.

The cyclic poly(dimethylsiloxane) is available, for example, under the designation Volatile Silicone 7207 (Trade Mark) from Union Carbide Corporation or Siloxane SWS03314 or 03400 (Trade Marks) from SWS Silicones, a division of Stauffer Chemical Company. These silicones can be characterised generally for example by the following constants, given by the manufacturer, for SWS43400; Specific Gravity 0.960 at 25"C; viscosity about 5 centistokes at 25"C and 98% volatile components.

The cyclic poly(dimethylsiloxane) is employed in an amount of 5% to 40 ,b by weight of the total composition, preferably from about 10% to about 20% by weight.

If a substantial excess above 40% is used, it leads to problems of insolubility of either the silicone or of other components, due to the reduced alcohol level, and a high incidence of gelling of the composition. In addition to the technical problems raised, higher amounts are uneconomical. If the amount used is less than 5 %, the silicone does not adequately fulfil its function. Particularly effective levels of silicone to avoid undue gelation and tackiness are from about 10to, to about 20too by weight.

The desirable anti-tack properties may be obtained by using instead of the cyclic poly(dimethylsiloxane) certain essentially non-volatile alcohol soluble poly(organosiloxanes), namely from 1 to 10% by weight of the composition of a polyphenylmethylsiloxane or a poly(higher alkyl siloxane) wherein each alkyl group contains at least three carbon atoms.

Particularly poly(methylphenylsiloxanes) that may be used are those having viscosities of about 15 to 65 centistokes at 25so. The poly(methylphenylsiloxanes) are available, for example, from the General Electric Company as SP-1075 methyl phenyl fluid (Trade Mark) or from Dow Corning as 556 Cosmetic Grade Fluid (Trade Mark).

The values reported for the 556 product are a viscosity of 22.5 centistokes at 25"C and a specific gravity of 0.980.

As exemplifying the poly(higher alkyl polysiloxanes) where the higher alkyl group has three or more carbon atoms, may be mentioned Union Carbide L43 (Trade Mark) having a viscosity of 12,000 centistokes at 25"C and a specific gravity of 1.08.

The amount of essentially non-volatile poly(organosiloxane) employed, whether polyalkylaryl, higher alkyl or a mixture of these, is from 1% to 10% by weight of the total composition, preferably from about 3% to about 5% by weight. If the amount used is too low, the composition is tacky on drying. If too much is used, the silicone leaves an undesirable oily residue on the skin. In addition, this fluid acts as a lubricant to prevent clogging of the pump spray nozzle or roll-ball of a roll-on applicator.

The silicone fluids used must, of course, be alcohol soluble and compatible with the other components and must result in a proper viscosity for a pump spray or a rollon.

Where a cyclic poly(dimethylsiloxane) is used, this being relatively volatile may tend to evaporate between uses from the orifice of the pump spray valve, and thus, in some pump valve constructions, may leave a powdery residue which may interfere with the next actuation of the pump. In the case of a roll-ball the above problem is evident in sticking of the roll-ball. It has been found that this problem may be substantially overcome by including in the composition from 0.5 to 10^to by weight of the composition of an essentially non-volatile poly(alkylsiloxane), poly(alkylarylsiloxane) or polyethersiloxane copolymer.

The essentially non-volatile poly(allrylsiloxanes) that may be used are, for example, poly(dimethylsiloxanes) with viscosities ranging from about 100 to 100,000 centistokes at 25"C. These siloxanes are available, for example, from the General Electric Company as the Viscasil (Trade Mark) series.

The essentially non-volatile poly(alkylarylsiloxanes) that may be used are, for example, poly(methylphenylsiloxanes) having viscosities of about 15 to 65 centistokes at 25"C. These siloxanes are available, for example, from the General Electric Company as SF1075 methyl phenyl fluid or from Dow Corning as 556 Cosmetic Grade Fluid.

The essentially non-volatile polyether siloxane copolymer that may be used is, for example, a dimethyl siloxane polyoxyalkylene ether copolymer fluid having a nominal viscosity of about 1,200 to 1,500 centistokes at 25"C. This copolymer is available, for example, from the General Electric Company as SF1066 organosilicone surfactant. Preferred compounds of this type are polysiloxane/ethylene glycol ether copolymers.

The preferred fluid is a poly(phenvlmethylsiloxane) with a viscosity of about 22.5 centistokes at 25 C and a specific gravity of 0.980 marketed as Dow Corning 556 by the Dow Corning Company.

The amount and type of non-volatile fluid employed is dependant on solubility in the alcohol/volatile silicone combination used. In the case of the non-volatile poly (dimethylsiloxane) fluids, not more than about 1 . by weight may be soluble in the composition. In the case of the polyalkylarylsiloxane and the polyethers siloxone copolymer, solubility of these silicone materials in either alcohol or the volatile silicone or mixtures of alcohol and volatile silicone is relatively high and thus the maximum amount used is enough to achieve the desired quality of lubricity. The amount of these latter siloxanes will thus vary from about 0.5o to about 10'',., preferably about 1 to about 3.50/,. If a substantial amount in excess of 10u, is used, an esthetically undesirable residue may be left. If the amount used is less than 0.5 )o', the silicone does not adequately fulfil its function.

As mentioned above, in addition to pump spray antiperspirants, the instant composition may be used as a roll-on deodorant either with or without incorporating a thickening agent to achieve the proper viscosity for application. If it is desirable to use a thickening agent, then any compatible thickening agent may be used in an amount sufficient to thicken the composition. A hydroxypropylcellulose thickener, such as Klucel Type G (Trade Mark) marketed by Hercules Powder Corporation, having a typical molecular weight of 300,000 may be used. The viscosity of a 2 solution of this hydroxypropylcellulose in ethanol will range from about 75 to 400 centipoise at 25"C.

The following Examples will more fully illustrate the invention. All parts and proportions referred to are by weight unless otherwise indicated.

Example 1 A number of compositions are prepared utilising Rehydrol by dissolving the Rehydrol (Trade Mark) in ethanol and then adding the other components. Sufficient Rehydrol is added, with stirring at ambient temperatures, to ethanol to result in a 30% by weight solution of Rehydrol. The balance of the alcohol is then added with stirring. The triple pressed stearic acid gel inhibitor (all stearic acid in the Examples is triple pressed and is an approximately 50% by weight mixture of stearic and myristic acids) is then stirred into the Rehydrol solution. The balance of the ingredients are then added with stirring to form a solution. The solution is then introduced into the desired applicator and tested.

The compositions prepared in the above manner together with results are given below.

TABLE 1 A B C D Comparative Example o % Rehydrol (Trade Mark) 10.0 15.0 20.0 15.0 Stearic acid 1.0 1.5 1.5 Isopropyl myristate 1.0 1.0 1.0 1.0 Alcohol (ethanol) 87.5 82.0 77.0 83.5 Perfume 0.5 0.5 0.5 0.5 100.0 100.0 100.0 100.0 Each of the Examples A to D produce an objectionable sticky feel during drying.

Example D, containing no gel inhibitor, gels on extended ageing.

TABLE 2 B F Comparative Example % Rehydrol (Trade Mark) 10.0 15.0 Stearic acid 1.0 3.5 Isopropyl myristate 1.0 1.0 Perfume 0.5 0.5 Ethanol 77.7 74.0 Trichlorotrifluoroethane (Freon 113) (Trade Mark) 9.8 Glycerine -- 6.0 100.0 100.0 Example E, utilising Freon 113 as a spray assist, produces a stinging sensation and is sticky during drying.

Example F, employing no silicone but utilising glycerine as a lubricant, feels very sticky during drying.

TABLE 3 1 2 3 4 5 6 7 8 9 10 Example % % % % % % % % % % Rehydrol (Trade Mark) 15.0 15.0 15.0 20.0 15.0 15.0 10.0 15.0 15.0 15.0 Isopropyl myristate 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Stearic acid 1.5 3.5 - 3.5 1.5 1.5 1.5 2.0 3.5 1.5 Volarile silicone 7207 (Trade Mark) 15.0 15.0 15.0 15.0 20.0 10.0 5.0 30.0 40.0 15.0 Perfume 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Ethanol 67.0 65.0 68.5 60.0 62.0 72.0 82.0 51.5 40.0 68.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 Example 1-very satisfactory, non-sticky, leaves skin dry, dries fast Example 2-very satisfactory, non-sticky, leaves skin dry, dries fast Example 3-non-sticky, but since it does not include a gel inhibitor, it gels on extended ageing Example 4-satisfactory Example 5-satisfactory, very slightly drier than 3 Example 6-satisfactory Example 7-using low levels of Rehydrol and silicone, is acceptable Example 8-utilising a relatively high level of silicone, gave good results Example 9-using a very high level of silicone, gave good results Example 10-using no skin emollient, gave good results TABLE 4 11 12 13 14 15 16 17 18 Example % % % o/O oi % o; % Rehydrol (Trade Mark) 15.0 15.0 15.0 15.0 14.0 10.0 15.0 15.0 Stearic acid 1.5 - - - 1.5 1.5 - Isostearic acid - 1.5 - - - - - Hexadecyl alcohol - - 3.0 - - - - - Crodafas N10 acid (Trade Mark) - - - 3.0 - - - Oleyl acohol - - - 1.0 - - - Isopropyl myristate - 1.0 1.0 - 1.0 1.0 - Volatile silicone 7207 (Trade Mark) 15.0 15.0 15.0 15.0 10.0 10.0 20.0 10.0 Aluminium chloride - - - - 1.0 - - Zirconium oxychloride - - - - - 1.0 - Ethanol 68.0 67.0 65.5 65.5 72.0 76.0 64.5 74.5 Perfume 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 * Oleyl ether phosphate marketed by Croda Ine Examples 11 to 14 inclusive varied the gel inhibitor and all four produced acceptable results Examples 15 and 16 vary the active component, both formulations produce acceptable results Examples 17 and 18 containing no gel inhibitor, give acceptable results and are stable for at least three months at room temperature and 105 F TABLE 5 G H 19 Example % Chlorhydrol (aluminium chlorhydroxide) (Trade Mark) 20.0 15.0 Rehydrol (Trade Mark) - - 15.0 Stearic acid - - 1.5 Solulan 98* (Trade Mark) 2.0 2.0 Isopropyl myristate - - 1.0 Siloxane SWS 03314 (Trade Mark) - 1.0 15.0 Perfume 0.5 0.5 0.5 Water 47.5 31.5 Klucel Type G (hydroxypropyl cellulose) (Trade Mark) - - 0.7 Ethanol 30.0 50.0 66.3 100.0 100.0 100.0 20 Example Alcohol soluble aluminium chlorhydrate 15.0 Stearic acid 1.5 Isopropyl myristate 1.0 Volatile silicone 7207 (Trade Mark) 15.0 Perfume 0.5 Ethanol 67.0 100.0 * An ethoxylated lanolin alcohol marketed by Amerchol, a division of CPC.

Conaperative Examples G and H, using chlorhydrol and water, are very sticky and slow drying.

Example 19 is a thickened composition suitable for a rall-on.

Example 20, utilising an alcohol soluble aluminium chlorhydrate other than Rehydrol, gave good results.

The following Tables 6 to 8 relate to examples of anti-perspirant compositions in accordance with the invention comprising the combination of a cyclic polydimethyl siloxane and a polyalkylsiloxane, polyalkylarylsiloxane or polyethersiloxane copolymer.

TABLE 6 21 22 23 25 Example % % % % Rehydrol (Trade Mark) 20.0 15.0 15.0 15.0 Stearic acid 2.0 3.5 - - Isopropyl myristate 1.0 1.0 1.0 1.0 Silicone fluid 556 (Trade Mark) 2.0 1.0 1.0 1.0 Volatile silicone 7207 (Trade Mark) 8.0 15.0 15.0 11.0 Ethanol 66.5 64.0 64.5 67.5 Perfume 0.5 0.5 0.5 0.5 Hexadecyl alcohol - - 3.0 Crodafas N10 acid (Trade Mark) - - - 3.0 Oleyl alcohol - - - 1.0 100.0 100.0 100.0 100.0 TABLE 7 25 26 27 28 Example % % % Rehydrol (Trade Mark) 15.0 15.0 15.0 15.0 Stearic acid 1.5 3.5 3.5 1.5 Isopropyl myristate 1.0 - - Volatile silicone 7207 (Trade Mark) 11.0 40.0 40.0 11.0 Silicone fluid 556 (Trade Mark) 1.0 - - Ethanol 70.0 40.0 40.0 70.0 Perfume 0.5 0.5 0.5 0.5 Poly(dimethylsiloxane): Viscasil (Trade Mark) (60,000 cs) - 1.0 - Poly(dimethylsiloxane): SF96 (Trade Mark) (350 cs) - - 1.0 Dow Corning 473 (Trade Mark) (polyether siloxane copolymer) - - - 2.0 100.0 100.0 100.0 100.0 TABLE 8 29 30 31 32 33 Example % % % Rehydrol (Trade Mark) 14.0 10.0 15.0 10.0 12.0 Stearic acid 1.5 - - 1.5 Isopropyl myristate 1.0 - - 1.0 1.0 Volatile silicone 7207 (Trade Mark) 10.0 11.0 12.0 10.0 12.0 Silicone fluid 556 (Trade Mark) 1.0 1.5 1.0 1.0 1.5 Ethanol 71.0 77.0 71.5 75.0 73.0 Perfume 0.5 0.5 0.5 0.5 0.5 Aluminium chloride 1.0 - - - Zirconium oxychloride - - - 1.0 100.0 100.0 100.0 100.0 100.0 Examples 21 to 33 inclusive produce acceptable compositions which are not sticky during drying. The inclusion of the polyalkylsiloxane, polyalkylarysiloxane or polyethersiloxane copolymer provides lubricity to the compositions whereby malfunctioning of the applicator is inhibited.

Examples 1 to 33 had the additional advantage, imparted by the cyclic polydimethylsiloxane, of giving the perception of quick drying.

Examples 34 to 41 given hereinafter relate to antiperspirant compositions of the invention containing a polyphenylmethylsiloxane or a poly higher alkyl siloxane but no cyclic polydimethylsiloxane. These siloxanes reduce the tackiness of the composi tions in which they are included and also are effective to impart lubricity to the compositions whereby malfunctioning of the applicator is inhibited.

Example 34 Rehydrol (Trade Mark) 15.0 Stearic acid 3.5 Isopropyl myristate 1.0 Perfume 0.5 Ethanol 76.5 Dow Corning Cosmetic Grade Fluid 556 (Trade Mark) 3.5 100.0 Example 34 is not sticky during drying.

TABLE 9 35 36 37 38 39 Example o o' !) Rehydrol (Trade Mark) 15.0 10.0 20.0 10.0 15.0 Stearic acid 3.5 2.0 3.5 - - Isopropyl myristate 1.0 1.0 1.0 - - Perfume 0.5 0.5 0.5 0.5 0.5 Ethanol 78.0 84.5 71.0 86.0 80.5 Dow Corning Cosmetic Grade Fluid 556 (Trade Mark) 2.0 2.0 4.0 3.5 4.0 100.0 100.0 100.0 100.0 100.0 Examples 35 to 37 have similar properties to Example 34. Examples 38 and 39 also give acceptable results and are stable for at least two months at room temperatures and 105"F.

Example 40 % Alcohol soluble aluminium chlorhydrate 15.0 Stearic acid 1.5 Isopropyl myristate 1.0 Dow Corning Cosmetic Grade Fluid 556 (Trade Mark) 3.5 Perfume 0.5 Ethanol 78.5 100.0 Example 41 Rehydrol (Trade Mark) 15.0 Stearic acid 2.0 Isopropyl myristate 1.0 Perfume 0.5 Ethanol 77.5 Union Carbide L-43 (Trade Mark) silicone fluid 4.0 100.0 Examples 40 and 41 give acceptable non-tacky results.

The Examples show that an antiperspirant composition which is suitable for application to the skin by means of a pump spray or a roll-on applicator and com- prising an alcoholic solution of an alcohol soluble aluminium chlorhydroxide such as Rehydrol is rendered much less tacky during drying by the incorporation therein of certain siloxanes in accordance with the present invention. The tack is measured either by subjective tactile analysis or by a compound lever assembly attached to an Instron machine which measures the tack of a particular composition in a graphical manner.

The Instron test assembly generally measures the force required to separate test surfaces. The formulation is spread on one surface and then a second surface is brought into contact with the first surface. As the Instron crosshead moves, the surfaces are separated. If the formulation is tacky during drying, an increase in the force necessary to separate the surfaccs is observed.

In addition to individual laboratory personnel measuring tack, the tack is also measured by the use of consumer panels. In such tests it is found that users appreciate the decrease in tackiness resulting frqm the use of the particular siloxanes according to this invention.

Claims (16)

WHAT WE CLAIM IS:

1. An antiperspirant composition suitable for applying to the skin from a pump spray applicator or a roll-on applicator, consisting of a liquid medium comprising: A. 40 to 86% by weight of the composition of a volatile cosmetically acceptable alcohol; B. 5 to 25% by weight of the composition of an alcohol soluble aluminium chlorhydroxide complex dissolved in said alcohol; and C. a liquid siloxane dissolved in the composition comprising: (a) 5 to 40% by weight of the composition of a cyclic poly(dimethyl siloxane) of the structural formula:

or (b) 1 to 10% by weight of the composition of a non-volatile poly(phenyl methylsiloxane) or a poly(higher alkyl siloxane) wherein each alkyl group contains at least three carbon atoms; the composition being free of pressurising propellant material.

2. An antiperspirant composition as claimed in claim 1, wherein the liquid siloxane comprises a mixture of said cyclic polydimethylsiloxane and from 0.5 to 10% by weight of the composition of a non-volatile poly(aLkylsiloxane), poly(alkylarylsiloxane) or polyether-siloxane copolymer.

3. An antiperspirant composition as claimed in claim 1 or claim 2, comprising a gel inhibitor in an amount sufficient to substantially reduce gelling thereof upon extended ageing.

4. An antiperspirant composition as claimed in claim 3, wherein said gel inhibitor is triple pressed stearic acid, isostearic acid, hexadecyl alcohol, oleyl alcohol or mixtures thereof.

5. An antiperspirant composition as claimed in claim 3 or 4, comprising 0.5 to 5% by weight of the composition of the gel inhibitor.

6. An antiperspirant composition as claimed in any of the proceding claims, wherein said component B is a 1,2-propylene glycol complex of aluminium chlorhydroxide.

7. An antiperspirant composition as claimed in claim 6, wherein said complex has the formula: Al2(H2O)0.7-1.1(OH)4.9-1.1(1,2-propylene glycol)0.7-1.3

8. An antiperspirant composition as claimed in claim 2, wherein said poly(alkylsiloxane) is a poly(dimethylsiloxane) having a viscosity of 100 to 100,000 centistokes at 250C.

9. An antiperspirant composition as claimed in claim 2, wherein said poly(alkylarylsiloxane) is a polymethylphenylsiloxane having a viscosity of 15 to 65 centistokes at 25"C.

10. An antiperspirant composition as claimed in claim 2, wherein said polyethersiloxane copolymer is a polysiloxane ethylene glycol ether copolymer having a viscosity of 200 to 1,500 centistokes at 25 C.

11. An antiperspirant composition as claimed in claim 1, wherein the poly(phenylmethylsiloxane) has a viscosity of 15 to 65 centistokes at 25"C.

12. An antiperspirant composition as claimed in any of the preceding claims comprising up to 10- < of an additional antiperspirant agent comprising aluminium chloride, zirconium oxychloride, basic aluminium bromide or a mixture thereof.

13. An antiperspirant composition as claimed in any preceding claim, containing less than 5o' by weight of water.

14. An antiperspirant composition substantially as herein described with reference to any of Examples 1 to 41.

15. An antiperspirant product comprising a composition as claimed in any of the preceding claims disposed in a pump spray applicator.

16. An antiperspirant product comprising a composition as claimed in any of claims 1 to 13 disposed in a roll-on applicator.