CA2239049A1 - Cosmetic compositions - Google Patents

Abstract

A cosmetic composition in the form of a water-in-oil emulsion comprising: (a) di scontinuous aqueous phase comprising an aqueous or hydroalcoholic solution of acidic skin care active; (b) continuous oil phase; and (c) pigment which has been coated with organosilicon component selected from a polyorganosiloxane and a silane, and mixtures thereof; characterised in that the aqueous phase has a pH of less than about 6 and the coated pigment has a hydrogen potential of less than about 2.0 ml H2/g of coated pigment. The compositions of the invention provide benefits in terms of reducing hydrogen gas generation and impr oving product stability.

Description

W O 97/20540 PCT~US96/18672 t COSMETIC COMPOSITIONS

Field of the Invention The ,~esent invention relates to cosmetic compositions and more particularly, to pigmented foundation make-up co,nposilions and concealers having anti-acne activity and enl~a"ced product stability.

Backqround of the Invention A foundation composition can be applied to the face and other parts of the body to even skin tone and texture and to hide pores, impe, re~ions, fine lines and the like. A foundation composition is also applied to moisturize the skin, to balance the oil level of the skin and to provide protection againstthe adverse effects of sunlight, wind and the harsh envi.unment.

Make-up compositions are generally available in the form of liquid or cream suspensions, emulsions, gels, pressed powders or anhydrous oil and wax compositions.

US Patent No. 3,444,291 ~iscloses a method of filling and camouflaging skin cavities by applying a composition which inchlcles 65 to 75 parts by weight of a microcrystalline wax and about 25 to 35 parts of a minerat oil.
The composition incln~:les a colourant, prererably a coal tar dye, for example, D &C Red No. 17, which malcl .es the colour of the usefs skin.

A spreadable, flowable and gre~seless cosll,elic cover-up composilion is taught in US Patent No 4,486,405. That co,nposilion is cl ,a~ac1e, i~ed by the presence of a first and a second alkoxylated 5~JJ ra-; a"t present in subsla, llially the same conc~"lralion.

US Patent No. 4,804,532 recites a facial cosmetic powder which utilizescrystalline silica in much lower co"cenlralior, than that employed in the then prior art compositions. This powder, used as a blush or a facial coating, is said to be effective in hiding skin wrinkles, lines and pores. The cGmposition is a mixture of a colour phase and a diluent phase. The colour -W O 97/20540 PCT~US96/18672 phase is formed by blending crystalline silica with colourants. The resultant colour phase is mixed with the diluent phase, essentially formed from nacreous materials such as talc and mica, to form the composition.

The use of a foundation composition which has a signfficantly high concel ,IraLiGn of nacreous material is taught in US Patent No. 3,978,207.
This foundation, a pressed powder co",posilion, is cha(acleri~ed by the presence of a nac~eous material such as mica and a binder oil which provides a frosted pearl effect, that is, a lustrous look. The colour of this foundation is provided by the . ,ac~ eous material.

US Patent No. 4,659,562 discloses a cosmetic make-up composition which incl~ ~des, as a binding agent, an intimate mixture of from 5 to 9~i weight ~er~,ll of a mixture of finely divided silica and about 5 to 95 weight percent of finely divided polyethylene fibres. The con~position is recited to maintain its uniformity over the areas of the skin to which it is applied. That is, it issaid to be "creaseproor'. The co""~osilion of the '562 patent inrl~des colourant in admixture with nacreous agents.

Nakamura et al., Preprints of the XlVth l.F.S.C.C. Congress, Barcelona,1986, Vol. I, 51~3 (1986) des~i~es a novel make-up composition utilizing spherical silica and polydimethyl siloxane. This combination is recited to provide a foundation which redl ~ces wrinkle visibiiity to a greater extent thanmake-up foundations with which it was coi"pared. This reduction in wrinkle visibility is c~used by optical blurring enhanced by the novel use of spherical silica and polydimethyl siloxane.

US Patent No. 5,143,722 discloses a cosmetic make-up con,posilion comprising water-in-oil emulsions co" ,,u. ising pigment coated with polysiloxane, a silicone phase, a water phase and a polydiorya~ ,osiloxane-polyoxyalkylene copolymeric surfactant.

Piylllents are i- ,cor~orate~ into cosmetic compositions to provide colour, coverage and enhanced skin a,vpeard. ,ce. For formulation of pigmented cos.nelic emulsion compositions it is ,c,referable to i, .co",ordle coated pigments. Unlike uncoated pig,nenls, coated piy")enls, e.g. silicone-coated pigments, have the advantage that they are '~ella~le" in silicone oils.

-CA 02239049 1998-0~-28 W O 97/20540 PCTfUS96/18672 Poly(methylhydrogen) siloxanes are known for us~ as coatings for pigments which are suitable for use in cosmetic compositions. Poly(methylhy.l(ogen) siloxanes contain reactive hydrogen ~unctionalities which provide substantivity to the pigment. However, a common unwanted side reaction of these materials when used in formulations in which water or alcohol is present is nucleophilic attack on resid~ Si-H functionality to generate hydro~~en gas as shown below:

-SiH + ROH -SiOR + H2 where ROH is water or alcohol.

The prod~ ~ction of hydrogen gas caused by the above reaction has been known to give rise to undesirable "bubbling" in formulations where pigments coated with silicon hydride~onlai"ing polysilo~dl ,es are used in the presence of water or alcohol at acidic pH. The compositions according to the present invention seek to solve this problem.

Since acidic skin care agents such as salicylic acid are most active at low pH (when a high c~"ce"lfalion of free acid is present in solution) it would be desirable to deliver the agent from an ~ eo~ ~s phase at a pH at which it exists significantly in protonaled form. It is acco~li"gly a primary object of this invention to provide a cosmetic composition comprising a low pl I
leo~ ~s solution of an acidic skin care active, which at the same time does not give rise to u, .desi, able evolution of hyd~ uge n gas.

It is also an object of the invention to provide a cosmetic cG",posilion having improved product stability.

It is a further object of the present invention to provide a cosmetic composition having improved anti-acne activity.

Summarv of the Invention In accordance with one aspect of the present invention, there is provided a cosmetic composition in the form of a water-in-oil emulsion comprising:

W O 97/~0540 PCT~US96/18672 ~a) discon~ UOUS aqueous phase comprising an aqueous or hydroalcoholic solution of acidic skin care activs (b) continuous oil phase; and (c) pigment which has been coated with org2"0silicon component selected from a pol~,urganosiloxane or a silane;

characLerised in that the aqueous phase has a pH of less than about 6 and the coated pigment has hydl ogel . potential of less than about 2.0 ml H2/g of coated pigment.

The cosmetic compositions of the present invention provide improved product stability and reduction of hydrogen gas generation.

All levels and ratios are by weight of total cor"~osiLion unless otherwise inrlicated Chain lengths and degrees of alkoxylation are also specified on a weight average basis.

Detailed DescriPtion of the Invention The cosmetic composilio, l accor,lil ,9 to the present invention co"~p, ises an ~q~eous phase cor,-~.rising an ~queous or hydroalcoholic solution of an acidic skin care active, an oil phase and a coated pigment. The co""~osilion is in the form of a water-in-oil emulsion.

A first essential component of the compositions of the present invention is an aqueous or hydroalcoholic solution of an acidic skin care active.

Suitabie skin care actives can be selected from hydroxycarboxylic acids. As used herein the term acidic skin care active means any skin care active containing an acidic functiGnal group (e.g. carL,oxy, sulfonic) S uiPhl~ hydroxycarboxylic acids can be seletcted from hydrox~",onocarboxylic acids having the following chemical structure:

W O 97/20540 PCT~US96118672 R1 (CR20H)m(CH2)nCooH
wherein R1, R2 = H, alkyl, aralkyl or aryl group of saturated or unsaturated, straight or branched chain or cyclic form, having from 1 to 2~ carbon atoms;
m=1,2,3,4,5,6,7,8 or 9; n=O or a numerical number up to 23.

The hydroxymonocarboxylic acid may be present as a free acid, lactone, or salt form, The lactone form could be either inter or intramolecular lactone, however, most common ones are intramolecular lactones with a ring structure formed by elimination of one or more water molecules between a hydroxy group and the carboxylic group. Since the hydroxymonocarboxylic acids are or~anic in nature, they may form a salt or a complex with an inorganic or organic base such as ar"",onium hydroxide, sodium or potassium hydroxide, or triethanolamine.

The hydroxymonoc~, boxylic acid and its related compounds may exist as stereoiso~ers such as D, L, and DL forms.

Typical alkyl, aralkyl and aryl groups for R1 and R2 include methyl, ethyl, propyl, isopropyl, benzyl and phenyl. The hyJ~ogen atoms of the R1 and R2 and (CH2)n may be substituted by a nonfunctional element such as F, Cl, Br, I, S or a radical such as a lower alkyl or alkoxy, saturated or unsaturated, having 1 to 9 carbon atoms. Represental;~/e hydroxy"~onoca.~oxylic acids are 2-hydroxyacetic acid (glycolic acid), 2-hydroxys,, u~Jdnoic acid (lactic acid), 2-methyl 2-hydroxyp, o,~ ooic acid (methyllactic acid), 2-hydroxybutanoic acid, phenyl 2-hydroxyacetic acid (mandelic acid), phenyl 2-methyl 2-hydroxyacetic acid, 3-phenyl 2-hydroxy~,o,~)a,loic acid (phenyllactic acid), 2,3-dihydrox~ ,opan-ic acid (glyceric acid), 2.3.4-trihydroxybutanoic acid, 2,3,4,~-tetrahydrox~,enlanoic acid, 2,3,4,5,6-~ "l~hydroxyhexanoic acid, 2-hydrox~rloder~ .oic acid (alpha hydroxylauric acid), 2,3,4,5,6,7-hexahydroxyl,ep~a"oic acid, diphenyl 2-hydroxyacetic acid (benzilic acid), 4-hydroxy"~a,.delic acid, 4-cl ,lor~" ,andelic acid, 3-hydroxybutanoic acid, 4-hydroxybutanoic acid, 2-hydroxyhexanoic acid, 5-hydroxydodecanoic acid, 12-hydroxydo~fec~rloic acid, 1 O-hydroxydecanoic acid, 1 6-hydroxyhP)~arle~noic acid, 2-hydroxy-3-methylbutanoic acid, 2-hydroxy4-methylpentanoic acid, 3-hydroxy-4-methoxymandelic acid, 4-hydroxy-3-methoxymendelic acid, 2-hydroxy-2-W O 97/20540 PCT~US96/18672 methylbutanoic acid, 3-(2-hydroxyphenyl) lactic acid, 3-(4-hydroxyphenyl) lactic acid, hexahydromandelic acid, 3-hydroxy-3-methylpentanoic acid, 4-hydroxydecanoic acid, 5-hydroxydecanoic acid and aleuritic acid.

Another type of hydroxyacid suitable for use herein is a hydroxydicarboxylic acid having the following formula:

HOOC(CHOH)m(CH23nCOOH

wherein m=1,2,3,4,5,6,7,8 or 9; n=O or an integer up to 23.

The hydroxydical L oxylic acid may also be present as a free acid, lactone or salt form. The hydroxyclicar~,oxylic acid and its related coln,uounds may also exist as stereoisomers such as D, L, DL and meso forms.

The hydrogen attached to the carbon atom may be sl Ihstit(lt~d by a nonfunctional element such as F, Cl, Br, 1, S, or a radical such as a lower saturated or unsaturated alkyl or alkoxy having from 1 to 9 carbon atoms.

Re~,rese"la~i~/e hydroxydica, boxylic acids are 2-hydroxy" o~a"edioic acid (tartronic acid), 2-hydroxybulaneclioic acid (malic acid), erythraric acid and threaric acid (tartaric acid), arabiraric acid, ribaric acid, xylaric acid and Iyxaric acid, glucaric acid (saccl ,a, ic acid), g~l~ct~ric acid (mucic acid), mannaric acid, gularic acid, allaric acid, altraric acid, idaric acid and talaric acid.

A third type of hydroxyacid s~ lit~hle for use herein is a miscell~neous group of cc " "Jounds which is not readily represenled by the above generic structure of either the first type or the secG"~ type described above.
Inrhlded in the third type of hydroxyacids are the following:

Hydroxycarboxylic acids of formula:

R(OH)m(cOoH)n wherein m, n=1,2,3,4,~,6,7,8 or 9, R=H, alkyl, aralkyl or aryl group of saturated or unsaturated, straight or branched chain or cyclic form, having -CA 02239049 1998-0~-28 W O 97/20540 PCT~US96/18672 . 7 from 1 to 25 carbon atoms; citric acid, isocitric acid, citramalic acid, agaricic acid (n-hexadecylcitric acid), quinic acid, uronic acids including glucuronic acid, glucuronolactone, ~ ctllronicacjd, ~ r,t~ nol~tone, hydroxypyruvic acid, hydroxypyruvic acid phospl ,ale, ascorbic acid, dihydroascorbic acid, dihydroxylal laric acid, 2-hydroxy-2-methylbutanoic acid, 1-hydroxy-1-cyclopropane carboxylic acid, 2-hydroxyhexanedial, 5-hydroxylysine, 3-hydroxy-2-aminopentanoic acid, tropic acid, 4-hydroxy-2,2-diphenylbutanoic acid, 3-hydroxy-3-methylglutaric acid, and 4-hydroxy-3-pentenoic acid.

The third type of hydroxyacid may also be present as a free acid, ia~;lo"e or salt form and may also exist as slereoisomers such as D, L, DL and meso forms.

The hydrogen atom attached to the carbon atom may be s~ 1hstitl Ited by a nonfunctional element such as F, Cl, Br, I, S or a radical such as a iower saturated or unsaturated alkyl or alkoxy having from 1 to 9 carbon atoms.

Mixtures of hydroxy acids can also be used in the compositions herein.
Hydroxy acids are useful herein from the viewpoint of reducing wrinkles and improving skin feel and appea~ a, .ce.

Other suitable hydroxy acids for use herein include salicylic acid, retinai~
acid, and ~el~ic acid.

P~t:fe"ed acidic skin care actives for use herein include salicylic acid, retinoic acid, ~el~ic acid, lactic acid, glycolic acid, pyruvic acid, and mixtures ll ,ereof, more preferably salicylic acid and ~PI~ic acid, and especially salicylic acid. The salicylic acid is useful herein as an anti-acne active.

The acidic skin care active is present at a ievel of from about 0.1% to about 10%, ~referably from about 0.1% to about 5%, more l~rt:fera~ly from about 0.5% to about 3%, by weight of composition.

The acidic skin care active is solubilized in water or a h~dl oalcoholic sol~ ~tion, for exa""~le, soll ~tions based upon C2-~6 alcohols, diols and W O 97/20540 PCT~US96/18672 polyols, preferred alcohols being selected from ethanol, dipropylene glycol, butylene glycol, hexylene glycol, and mixtures thereof. Alcohol is preferably present in the compositions herein at a level of from about 1% to about 2t~%. The final aqueous/hydroalcoholic skin care active solution pre~erably has a pH at ambient temperature (25~C) of less than about pKa + 1, where PKa is the logarithmic acidity constant for the fully protonated skin care active. In pr~fer,~d embodiments, the pH of the final solution is less than about pKa The lo~arill ",iic acidity CGI ISt~ is thus defined by rerer~"ce to the equilibrium H+ + Hn_1A = HnA

where HnA is the fully ,~n~tonat6d acid, n is the number of protons in the fully proL~ lell acid and Hn 1 A is the conjugate base of the acid co" espo, Idin~ to loss of one proton.

The acidity cor)slanl for this equilibrium is therefo, e Kn = ~HnA]
[H+] [~n-1A]
and PKa = 1~910Kn For the purposes of this specir~calio~ ~, acidity con~ld. Ils are defined at 25~C
and at zero ionic sll ~ngtl 1. Literature values are taken where possihle (see Stability CGn slanl~ of Metal-lon Complexes, Special Pl ~hlic~tion No. 25, The Cl ,e." sal Society, London); where doubt arises they are deter."ined by ~otenlior"el. ic titration using a glass electrode.

- The PKa ~f the acidic skin care active used herein is preferably in the range of from about 1 to about 5.5, more ,ureferably from about 2 to about 4.5, espec;ally from about 2 to about 4.

CA 02239049 1998-0~-28 W O 97/20540 PCT~US96/18672 The pH of the aqueous phase is less than about pH 6 pre~erably from about pH 2 to about pH 5 more preferably from about pH 2.5 to about pH 4. At pH
values of less than about 5 the ~ueoLIs phase is ~ efeldl~ly free of acid Iabile species such as polyacrylic or polymethacrylic acids or esters.

The compositions of the presenl invention can also comprise a solubilizing agent for solubilizing the acidic skin care active. Preferably the solubilizing agent herein is selected from pyrrolidone-based solubilising agents, polyethylene glycol based nonionic surfactants having an HLB of y, ~ler than about 15 preferably greater than about 18 and mixtures thereof. The solubilizing agent herein is ~ ,~rerably present at a level of from about 0.1%
to about 1û%, more prerefal~ly from about 0.1% to about 5% especinlly from about 0.5% to about 2% by weight of composition.

Pyrrolidone-based solubilising agents s~lit~hle for use herein include polyvinylpyrrolidone or C1-C4 alkyl polyvinylpyrrolidone having a molecular weight (viscosity average) in the range from about 1500 to about 1 500 000 pr~fe, dbly from about 3000 to about 700 000, more prererdbly from about 5000 to about 100 000. Suitable examples of pyrrolidone-based solubilising agents are polyvinylpyrrolidone (PVP) (or povidone) and butylated polyvinylpyrrolidone. The most preferred pyrrolidone-based solubilising agent herein is polyvinylpyrrolidone. PVP is ool~ ercialiy available under the trade name Luviskol (RTM) from BASF. A ~ rt7r~l led PVP solubilising agent herein is Luviskol K17 which has a viscosity-average molecular weight of about 9,000. Other pyrrolidone-based sol~ ~hilising agents for use herein include C1-C1g alkyl or hydroxyalkyl pyrrolidones such as lauryl pyrrolidone.

The pyrrolidone-based solubilising agent is pr~rerably pr~sel,l in the co~,~posilion herein in a level of from about 0.1% to about 10% more preferably from about 0.1% to about 5% especially from about û.~% to about 2% by weight of co""~osilion. The weight ratio of acidic skin care active: pyrrolidone-based solubilising agent is prererably in the range from about 10:1 to about 1:10 more preferably from about 5:1 to about 1:5.

rrerer, ed embodiments of the invention ~ ilionally comprise from about 0.01% to about 5% by weight of an additional acid or salt thereof which is soluble in water at pH values of less than or equal to the PKa Of the co" ~sponding acid, for example, an acid selected from citric acid, boric acid, and salts, and mixtures thereof. These materials are valuable herein in combination with the pyrrolidone-based complexing agent from the viewpoint of aiding solubilization of the acidic skin care active. Particularly preferred herein from this viewpoint is a sodium salt of citric acid. In preferred embodiments, the acid or salt thereof is solu~le to a level of at least 5% w/w at 25~C.

The composition of the present invention is in the form of a water-in-oil emuision, wherein in preferred Pmbodiments the oil phase co~ rises a mixture of volatile silicones and non-volatile silicones. The silicone fluid is present in an amount of from about 1% to about 50% by weight. Suitable volatile silicones include cyclic and linear volatile polyors~anosiloxanes. The term "nonvolatile" as used herein shall mean that the material exhibits very low or no significant vapor pressure at ambient conditions, as is understood by those in the art. in general, this will mean no more than 0.2 mm Hg at one atmosphere and 25~C.

A description of various volatile silicones is found in Todd, et al.. ' \/olatile Silicone Fluids for Cosmetics", 91 Cos")elics and Toiletnes 27-32 (1976).

r,efer,~d cyclic silicones include polyJ;n,eU,ylsiloxanes contair,iny an average of from about 3 to about 9 silicon atoms, prererably from about 4 to about 5 silicon atoms. r~ ef~, .ed linear silicones include the polydi"leU,ylsiloxa"es con l.dil ,ing an average of from about 3 to about 9 silicon atoms. The linear volatile silicones generally have viscosilies of less than about 5 cenli~,lolces at 25~C, while the cyclic r"aterials have viscositiesof less than about 10 centistokes. Examples of silicone oils useful in the present invention include: Dow Corning 344, Dow Coming 21330, Dow Corning 345, and Dow Coming 200 (manufactured by the Dow Corning Corporation): Silicone 7207 and Silicone 7158 (manufactured by the Union Carbide Cor~ oralion). SF:202 (manufactured by General Electric) and SWS-03314 ~manufactured by Stauffer Chemical).

Suitable non-volatile silicones pl eferably have an average viscosity of from about 1,000 to about 2,000,000 mm2.s~1 at 25~C. more prefer~bly from CA 02239049 1998-0~-28 W O 97/20540 PCT~US96/18672 about 10,000 to about 1,800,000 mm2.s-1, even more prefer~bly from about 100,000 to about 1,500,000 mm2.s~1. Lower viscosity non-volatile silicone con~itioning agents, however, can also be used. Viscosity can be measured by means of a glass capillary viscometer as set forth in Dow Corning Corporate Test Method CTM0004, July 20, 1970. Suitable non-volatile silicone fluids for use herein include polyalkyi siloxanes, polyaryl siloxanes, polyalkylaryl siloxanes, polysiloxanes with amino functional substitutions, polyether siloxane copolymers, and mixtures thereof. The siloxanes useful in the present invention may be endcapped with any number of moieties, including, for example, methyl, hydroxyl, ethylene oxide, propylene oxide, amino and carboxyl. However, other silicone fluids having skin conditioning properties may be used. The non-volatile polyalkyl siloxane fluids that may be used include, for exa,n,ole, polydimethylsiloxanes. These siloxanes are available, for example, from the General Electric CGI~PanY as a Viscasil (RTM) series and from Dow Corning as the Dow Corning 200 series. Prereral.ly, the viscosily ranges from about 10 mm2.s~1 to about 100,000 mm2.s~1 at 25~C. The polyalkylaryl siloxane fluids that may be used, also include, for example, polymethylphenylsiloxanes. These siloxanes are available, for example, from the General Electric Company as SF 1075 methyl phenyl fluid or from Dow Corning as 556 Cosmetic Grade Fluid. The polyether siloxane copolymer that may be used inclu~es, for example, a polypropylene oxide modified dimethylpolysiloxane (e.g., Dow Coming DC-1248) although ethylene oxide or mixtures of ethylene oxide and propylene oxide may also be used.

References ~I;sclosing suitable silicone fluids include US-A-2,826,551,Green; US-A-3,964,500, Drakoff, issued June 22nd, 1976; US-A-4,364,837, Pader; and GB-A-849,433, Woolston. In addition, Silicone Compounds distributed by relra,~;l, Systems inc., 1984 provides an ex~el,sive (though not exclusive) listing of suita~le silicone fluids.

rrefer. ed non-volatile silicones for use herein include polyd;of9anosilox~rle polyoxyalkylene copolymers cGnlai"i- ,g at least one polydiorganosiloY~ne segment and at least one polyoxyalkylene segment, said polydiorganosiloxane segment consisting essentially of R~sio(4-b)l2 siloxane units wherein b has a value of from about 0 to about 3, inclusive, there being an average value of approximately 2 R r~di~ s per silicon for all siloxane units in the copolymer, and R denotes a radical selected from methyl, ethyl, vinyl, phenyl and a divalent radical bonding said polyoxyaikylene segment to the polydiorganosilox~ne sey",e"l, at least about 95% of all R radicals being methyl; and said polyoxyalkylene sey",enl having an average molecular weight of at least about 500, preferably at least about 1000 and consisting of from about 0 to about 50 mol percent polyoxypropylene units and from about 50 to about 100 mol ~.~rcen( polyoxyethylene units, at least one terminal portion of said polyoxyalkylene segment being bonded to said polydioryanosilox:lne sey",enl, any terminal portion of said polyoxyalkylene segment not bonded to said polydiorganosilox~rle segment being satisfied by a ter",inali"y radical; the weight ratio of polydiorganosiloxane segments to polyoxyalkylene sey",ents in said copolymer having a value of from about 2 to about 8. Such polymers are des~, il,e~ in US-A4,268,499.

More ~,rerer, ed for use herein are polydi: rgd"osiloY~ne-polyoxyalkylene copolymers having the general formula:

H3C-- si --o (si--~)x (si o)y si CH3 o (C2H40)a(C3H60)bR

W O 97/20540 PCT~US96/18672 . 1 3 wherein x and y are selected such that the weight ratio of polydiorganosiloxane segments to polyoxalkylene segments is from about 2 to about 8, the mol ratio of a:(a+b~ is from about 0.~ to about 1, and R is a chain terminating group, especi~lly selected from hydrogen; hydroxyl; alkyl, such as methyl, ethyl, propyl, butyl, benzyl; aryl, such as phenyl; alkoxy such as methoxy, ethoxy, propoxy, butoxy; benzyloxy; aryloxy, such as phenoxy; alkenyloxy, such as vinyloxy and allyloxy; acyloxy, such as acetoxy, acryloxy and propionoxy and amino, such as dimethylamino.

The number of and average molecular weights of the segments in the copolymer are such that the weight ratio of polydiorganosiloY~ne se~".en(s to polyoxyalkylene segments in the copolymer is pr~ferdL)ly from about 2.5 to about 4Ø

Suitable copolymers are available commercially under the trade"a",es Belsil (RTM) from Wacker-Chemie GmbH, Gescnaftsbereich S, Posffach D-8000 Munich 22 and Abil (RTM) from Th. Goldschmidt Ltd,. Tego House, Victoria Road, Ruislip, Midd1esex, HA4 OYL. Particularly ~refer, ~d for use herein are Belsil (RTM) 6031, Abil (RTM) B88183, DC3225C, DC5200, Abil WeO9 and Abil EM90. A p,refer,ed silicone herein is known by its CTFA
designation as dimethicone copolyol.

The silicone oil phase prererably co"",rises from about 2% to about 25%, more ~.referably from about 5% to about 15% by weight of composition of non-volatile silicones.

A third esse. ~lial cGrl lpol ,e. ll of the present invention is a pigment which has been coated with organosilicon cor"~onent selected from a polyor~~a"osiloxane or a silane wherein the coated pigment has a hyJI oyen potential of less than about 2.0, prerer~bly less than about 1.0, more ,c,rer~raL,ly less than about 0.5 ml, and especially less than about 0.1ml H2/g of coated piylllel ll. The pigment used herein is in particul~te form. The pigment is illcor~Joraled into the continuous oil phase in the cori",osilions herein. The coc,lings used can be bonded to the pigment surface by covalent bondi"y, physical adsor~lion or adhesion, preferably by covalent bonding to the surface of the pigment. The function of the coatings herein is to hydrophobicaily-modify the piymel lts so that thay are '~ettable" in the W O 97/20~40 PCT~US96/18672 continuous silicone phase of the water-in-siiicone emulsions. The coated pigment is also useful herein from the viewpoint of reducing hydrogen gas evolution and improving product stability.

Without wishing to be limited by theory it is believed that although tne pigments are present in the oil phase of the water-in-oil emulsion, hydrogen ions from the aqueous phase can pass through the interface of the emulsion into the oil phase, where they are available to react with the pigment coatings, e.g. to give off hydrogen gas. However, by using organosilicon-coated pigments having a hy-llog6" potential of less than about 2 ml H2/g of coated pigment, hydrogen gas generation is red~ ~ced The hydrogen potential of the coated pi~"~ent is measured herein using the foliowing test method:

A dispersion of the coated piy"~e, ll containing 20g of coated pigment is placed in a flask on a magnetic stirrer and 1 OOml of a 2% ethanolic solution of potassium hydroxide is added with stirring at ambient te""~eralure. The hydrogen gas which is eYolved is collected in a second flask at ambient temperature and pressure (25~C, 1At). The h~,.l,ogen gas relca~.cd can therefore be volumetrically measured.

A wide variety of organosilicon components can be used for treating thepig",enls herein. A suitable polyorganosiloxane herein is selected from:

(A) material of the formula:

(R1 )3Sio-(si(R2R3~o)p-si(R2R3)oA2 wherein p is 1 to 1000, ~,referably from 1 to 100, A2 is hydro~en or an alkyl group having from 1 to 30 carbon atoms, R1 is a C1-C30 alkyl, preferably methyl, R2 and R3 are indepel ,der,lly selected from a C1 -C30 alkyl and a phenyl, preferably wherein R2 and R3 are both methyl or wherein R2 is methyl and R3 is phenyl; or ~B) material of the formula:

W O 97~0540 PCT~US96/18672 (R1)3SiO(Si(R2)(H)-O)j-Si(R1)3 wherein i is 1 to 1000, preferably 1 to 100, and wherein R1 and R2 are as defined above for formula (A).

~ In prerer~ ed embodiments the organosilicon component is select~d from a silane. The silane can be selected from material of the formula:

(C) A1 SiX1 X2X3 wherein A is an alkyl or alkenyl group having from 1 to 30 carbon atoms, and X1, X2 and X3 are independently C1-C4 alkoxy preferabiy methoxy or ethoxy, or halo, pr~ferably chioro.

When the pigment herein is treated with silane material having the formula (C) described herein above a pigment having the following formula (1 ) is produced:

P-o-si(oH)(A)-~-o-si(oH)(A)-]o-1 oo-~H

wherein P is an atom in the pigment surface and each A is an alkyl or alkenyl group having up to 30 carbon atoms. A number of a~jacent polysiloxa"e chains as shown in formula (1 ) can be cross-linked through oxygen atoms to form a polysiloxane chain with up to 100 repeating -Si(-OP)-O-units that extend along the pigment surface, in addition to the polysiloxdne chain which extends away from the pigment surface.
Examples of linear or bra~ ,ched alkyl groups are methyl, ethyl, propyi, butyl, pentyl, hexyl, heptyl, octyi, and so forth up to oct~decyl. "Alkenyl" incl~ ~descarbon chains with one or mors double bonds; examples of such groups include ethylene, propylene, acrylyl, methacrylyl, and residues of unsaturated fatty acids such as oleic (C17C33-), linoleic (C17H31-), and linoleniC (C17i~ 29-) r When the pigment herein is treated with polyorganosilox~ne material having the formula (A) described hereinabove a pigment having tha following formula (2) is pro~ucett W O 97/20540 PCT~US96/18672 P-o-(Si(R2R3)0)p-Si(R1)3 (2) wherein p is 1-1000, pre~erably 1 to 100, R1, R2 and R3 are as defined above for formula (A) and P is an atom in the pigment surface.

When the pigment herein is treated with polyorganosiloxane material having the formula (B) described hereinabove a pigment having the following formula (3) is produced:
(R1 )3SiO-ISi~R2)(-OP)-O-lp-Si(R1 )3 ~3) wherein each P is an atom in the pigment surface, p is from 1 to 1000, prt:rer~bly from 1 to 100, R1 and R2 are as defined above in formula (B) and in which each of the up to 100 repeating (Si-O) units is bonded through an oxygen atom to the pigment surface.

The pigment (or a mixture of two or more pigments) can be coated by placing it in dry, ~Inely divided form in a mixer, adding the organosilicon component, and mixing. The orgd"osilicon coali"5~ is prefefably present at a level of from about 0.01% to about 5%, more preferably from about 0.1%
to about 4%, and especi~lly from about 0.5% to about 2%, by weight of the organosilicon coated pigment.

The most prefe".3d coated pigment from the viewpoint of reducing hydrogen gas evolution and improving product stability is Cardre 70429.

Suitable pigments for use herein can be i"~rgdnie and/or orgd"ic. Also incll ~4d within the term pigment are IllaL~l ials having a low colour or lustresuch as matte r" ,isl~ing agents, and aiso light s~tleri"g agents. Examples of suitable ,c iy"~e~ lls are iron oxides, rutile titanium clioxide, anatase titanium dioxide, ferric oxide, ferrous oxide, ci ,ro,nium oxide, chromuim hydroxicle, manganese violet, acylglul~",a~e iron oxides, ull,afnarine blue, D&C dyes, carmine, and mixtures thereof. Depending upon the type of make-up composition, eg. foundation or blusher, a mixture of pigments will normally be used.

-The foundation composition can also include at least onQ matte finishing agent. (The term matte finishing agents is included within the term pigment). The function of the matte finishing agent is to hide skin defects and reduce shine. Such cosmetically acceptal,le il ,o, 9dl)iC agents, i.e., those inclu~le~l in the CTFA Cosmetic Ingredient Dictionary, Third Ed., as silica, hydrated silica, silicone-treated silica beads, mica, talc, polyethylene, titanium dioxide, bentonite, hectorite, kaolin, chalk, cJi~lol"aceous earth, attapulgite, and the like may be utili7e~f Of particular usefulness as a matte finishing agent is low lustre pigment such as liLal l~le.l mica (mica coated with titanium dioxide) coated with barium sulf~te. Of the inoryd"ic co"~ponents useful as a matte finishing agent low lustre pigment, talc, polyethylene, hydrated silica1 kaolin, titanium dioxide and mixtures thereof are particularly pref~r, ~d. Materials suitable for use herein as light-scalle~ i"g agents can be generally desc, ibed as spherical shaped inClrs~dl liCmaterials having a particle size of up to about 100 Il,i~,-,ns, ,~J, e~erably from about 5 to about 50 microns, for example spherical silica particles. Zinc oxide is not prefer, ed for use in the oo")~,osiliGns herein.

Other examples of pigments inctude ,'akes of organic colorants such as FD&C Red No. 7 calcium lake, FD&C Yellow No. 5 aluminium lake, D&C
Red No. 9 barium lake, and D&C Red No. 30.

The total co"cena, alio,- of the coated pigment may be from about 0.1 to about 25% by weight and is preferably from about 1 to about 15%, more preferably from about 8~/o to about 12% by weight of the total composition, the exact concenlrdlio" being dependent to some extent upon the specific mixture of piy"~en~s selecte~l for use in a foundation make-up or blusher to achieve the desired shades. The F,rerer, ed cG"~posilions contain from about 2% to about 20% by weight of titanium clio,cide and most prerer~bly from about 5% to about 10% by weight of titanium dioxide.

A highly prerer, ~d CO"~ Ol ,ent of the col"posilions herein is a humectant or mixture of humectants. The humectant or mixture of humectants herein is present in an amount of from about 0.1% to about 30% pre~rably from about 1% to about 25%, and more l.rererably from about 1% to about 10%
by weight of composition. Suitable humectdnls are selected from glycerine and polyglycerylmethacrylate lubl icar,t having a viscosity at 25~C of 300,000 W O 97/20540 PCTnUS96/18672 to 1,100,000 cps; a specific gravity at 25~C of 1 to 1.2g/ml, a pl I of 5.0 to 5.5; a bound water content of 33 to 58%; and, a free water contenl from 5 to 20o~

The humectant can be incor,,orated at least partly into the oil phase of the water-in-oil emulsion. The oil phase prererably cc l~lprises from about 0.1%
to about 10%, more preferably from about 0.1% to about 3% by weight of humectant on a composition basis. The humectant can be introduced into the oil phase in the form of a mixture with or incor~oraled within a particulate lipophilic or hydrophobic carrier material.

Polyglycerylmethacrylate lubricants having the desired properties are marketed by Guardian Chemical Corporation under the trademark "Lubrajel". The "Lubrajels" identified as "Lubrajei D\/', "Lubrajel MS", and "Lubrajel CG" are p,efel,ed in the present invention. The gelling agents sold under these trademarks co"tain about 1% propylene glycol.

Other S!'it~hlR humectants include sorbitol, panthenols, propylene glycol, dipropylene glycol, butylene glycol, hexylene glycol, alkoxylated 9l~ ~cose derivatives, such as Glucam ~RTM~ E-20, hexanetriol, and gll ~cose ethers, and mixtures thereof.

The panthenol moisturiser can be selected from D-panthenol (lR~-2,4-dihydroxy-N-[3-hydroxypropyl)l-3,3-dim~:U Iylbulal "ide), DL-panthenol, calcium panlolllenate, royal jelly, panthetine, p~nloU,eine, panthenyl ethyl ether, ,t~anS~an)ic acid, pyridoxin, pantoyl l~ctose and Vitamin B co,nplex.

The pr~rer, ed humectant herein is glycerine. Chemically, glycerine is 1,2,3-propanetriol and is a product of cGr ,r"erce.

The balance of the co,n,~osition of the present invention is deia"i ed water.
The cG".pos;lion ,~,erera~ly co,nprises from about 20% to about 95%, more prererably from about 40% to about 80% by weight of the oil phase, and from about 5% to about 80%, more pre~erably from about 20% to about 60%
by weight of the water phase.

W O 97/20540 PCT~US96/18672 The make-up compositions of the present inYention can also comprise a particulate cross-linked hydrophobic acrylate or methacrylate copolymer.
This copolymer is particularly v~lu~hlc for reducing shine and controlling oil while helping to provide effective moisturization benefits. The cross-linked hydrophobic polymer is prefer~bly in the form of a copolymer lattice with at least one active ingredient d;sp~r~ed uniformly throughout and en~,apped within the copolymer lattice. Alternatively the hydrophobic polymer can take the form of a porous particle having a surface area (N2-BET) in the range from about 50 to 5~0 prere,~bly 100 to 300m2/9 and having the active ingredient absorbed therein.

The cross-linked hydrophobic polymer when used herein is in an amount of from about 0.1% to about 10% by weight and is 1~ efe, ably i"cor~or~Led in the external silicone-containing oil phase. The active ingredient can be one or more or a mixture of skin compatible oils skin co""~aliL,le humectants emollients moisturizing agents and sunscreens. The polymer ")ale,i21 is in the form of a powder the powder being a combined system of particles.
The system of powder particles forms a lattice which includes unit particles of less than about one micron in average cJia,neter agglG,.,erates of fused unit particles of sizes in the range of about 20 to 100 microns in average dia"leler and agy,e~ates of clusters of fused a~glo",erates of sizes in the range of about 200 to 1 200 microns in average dia",eter.

The powder ",ale,ial of the present invention which can be employed as the carrier for the active ingredient can be broadly des.;, iL ed as a cross-linked post absorbed hydrophobic polymer lattice. The powder prererably has e"l, apped and dispersed therein an active which may be in the form of a solid liquid or gas. The lattice is in partic~ te form and co, Isli(~ ~tes free flowing discrete solid particles when loaded with the active ",aterial. The lattice may co. ,tain a predeter",i"ed quantity of the active ,nale, ial. The polymer has the structural formula:

CA 02239049 l998-05-28 W O 97/20540 PCT~US96/18672 CH3 ~ CH3 C=O C=O
O O
R' - R" - Y
o C=O
--C~2--C
CH3 ~ X

where the ratio of x to y is 80:20 R' is -CH2CH2- and R' is -~CH2)1 1 CH3-The hydro~l .obic polymer is a highly crosslinked polymer more particularly a highly cross-linked polymethacrylate copolymer. The ",alerial is manufactured by the Dow Corning Corporation, MiJlar,d. Michigan USA
and sold under the trademark POLYTRAP (RTM) . It is an ultralight free-flowing white powder and the particles are capable of absG,Ling high levels of lipophilic liquids and some hydrophilic liquids while at the same time "-ainlaWng a free-flowing powder character. The powder structure consists of a lattice of unit particles less than one micron that are fused into agglomerates of 20 to 100 micr(Jns and the agglo",erates are loosely clustered into macro-particles or aggregates of about 200 to about 1200 micron size. The polymer powder is car~hle of co. .lai"ing as much as four times its weight of fluids emulsions dispersions or melted solids.

Adso".lion of actives onto the polymer powder can be accon"~lished using a stainless steel mixing bowl and a spoon wherein the active is added to the powder and the spoon is used to gently fold the active into the polymer powder. Low viscosity fluids may be adsorbed by ~ddilio" of the fluids to a se~l~hle vessel containing the polymer and then tumbling the materials until a consistency is achieved. More elaborate blending equi~",Gnl such as ribbon or twin cone blenders can also be employed. The ~refer, ed active ingredient for use herein is glycerine. Prefer~Lly the weight ratio of hul~eclal ,t: carrier is from about 1:4 to about 3:1.

CA 02239049 1998-0~-28 W O 97/20540 PCT~US96/18672 Also suitable as a highly cross-linked polymethacrylate copolymer is Microsponges 5647. This takes the form of generally spherical particles of cross-linked hydrophobic polymer having a pore size of from about 0.01 to about 0.05ym and a surface area of 200-300m2/g. Again, it is prererably loaded with humectant in the levels described above.

The compositions of the invention can also contain a hydrophilic gelling agent at a level preferably from about 0.01 % to about 10%, more pre~erably from about 0.02% to about 2%, and especially from about 0.02% to about 0.5%. The gelling agent prererably has a viscosily (1 % aqueous solution, 20~C, Brookfield RVT) of at least about 4000 mPa.s, more ,c,referably at least about 10,000 mPa.s and especially at least 50,000 mPa.s.

Suitable hydrophilic geliing agents can generally be described as water-soluble or colloidally water-soluble polymers, and include celll ~'ose ethers (e.g. hydroxyethyl cellulose, methyl cellulose, hydroxypropylmethyl cellulose), polyvinylalcohol, polyquaternium-10, guar gum, hydroxypropyl guar gum and xanthan gum.

Among suitable hydrophilic gelling agents are acrylic acid/alkyl acrylate copolymers and the ca, ~oxyvinyl polymers sold by the B.F. Good~
CGmPanY under the trade mark of Car6Opol resins. These resins consist essentially of a colloidally water-sol~ Ihle polyalkenyl polyether crosslinked polymer of acrylic acid crosslinked with from 0.75% to 2.00% of a crosslinking agent such as for example polyallyl sucrose or polyallyl pentaerythritol. Examples include Ca.L,opol 934, Carbopol 940, Carbopol 950, Carbopol 980, Cal ~o~ol 951 and Ca, bGpOI 981. Carl,opol 934 is a water-soll ~hle polymer of acrylic acid crosslinked with about 1 % of a polyallyl ether of sucrose having an average of about 5.8 allyl groups for each sucrose molecule. Also suitable for use herein are hyd~opl~obically-modified cross-linked polymers of acrylic acid having amphipdlhic properties available under the Trade Name Carbopol 1382, Carbopol 1342 and Pemulen TR-1 (CTFA Design dtiOn Acrylates/10-30 Alkyl Acrylate Crosspolymer). A co",L,i"dlion of the polyalkenyl polyether cross-link~d acrylic acid polymer and the hy-J(o,vl ,obically modified cross-linked acrylic acid polymer is also suitable for use herein. Other suitable gelling agents suitable for use herein are oleogels such as trihydroxyslea, i, . and aluminium W O 97/20540 PCT~US96/18672 magnesium hydroxy stearate. The gelling agents herein are particularly valuable for providing excellent stability characteristics over both normal and elevated temperatures.

Neutralizing agents suitable for use in neutralizing acidic group containing hydrophilic gelling agents herein include sodium hydroxide, pot~ssi~ l~ hydroxide, a"~,l,onium hydroxide, monoethanolamine, diethanolamine and triell~dl,o~amine.

The make-up cor~r~sitions herein can additionally CGIll~l ise an emollient.
~mollients suitable for the co",posilions of the present invention include natural and synthetic oils selected from mineral, vegetable, and animal oils, fats and waxes, fatty acid esters, fatty alcohols, alkylene glycol and polyalkylene glycol ethers and esters, fatty acids and mixtures thereof.

Suitable emollients for use herein include, for exal."~le, optionally hydroxy-substituted Cg-Cso unsaturated fatty acids and esters thereof, C1-C24 esters of C8-C30 saturated fatty acids such as isopro,~yl myristate, cetyl palmitate and octyldodecylmyristate (Wickenol 142), beeswax, saturated and unsaturated fatty alcohols such as behenyl alcohol an~ cetyl alcohol, hyd~oc~r~ons such as mineral oils, petrolatum and s~u~l~ne, fatty sorbitan esters (see US-A-3988255, Seiden, issued October 26 1976), lanolin and lanolin derivatives, such as lanolin alcohol ethoxylated, hydroxylated and acetylated lanoli"s, cholesterol and derivatives thereof, animal and vegetable triglycerides such as almond oil, peanut oil, wheat germ oil, I;nseed oil, jo~oba oil, oil of apricot pits, walnuts, palm nuts, ~Jislacl,io nuts, sesame seeds, rapeseed, cade oil, corn oil, peach pit oil, poppyseed oil, pine oil, castor oil, soybean oil, avocado oil, safflower oil, coconut oil, hazelnut oil, olive oil, gt~peseed oil, and sunflower seed oil and C1 C24 esters of dimer and trimer acids such as diisopropyl dimerate, diisoslea, ylmalate, diisoslearyldimerate and ll iiso~le~ ylll i. . .erale.

rlefer,ad emollients are selected from hy~l~ocarL.ons such as isohP~ dec~na, mineral oils, petrolatum and s~u~ e, lanolin alcohol, and stearyl alcohol. These emollients may be used independently or in mixtures and may be present in the composition of the pr~sent invention in an amount from about 1% to about 30% by weight, and prererably are present W O 97/20540 PCT~US96/18672 . 23 in an amount from about 5% to about 15% by weight of the total composition.

The composition may also contain additional materials such as, for example, fragrances, fillers such as nylon, sun-screens, preservatives, electrolytes such as sodium chloride, proteins, antioxidants, chelating agents and water-in-oil Pmulsifiers as appr~"~"iate.

Another optional cor"ponent of the make-up cor,~l~osilion is one or more ultraviolet absorbing agents. Ultraviolet absorbing agents, often desc, ibed as sunscreening agents, can be present in a cGncenl~lion in the range of between about 1% and about 12% by weight, based on the total weight of co""~osilion. Preferably, the UV absorbing agents constitute between about 2% and 8% by weight. More prefe(ably, the UV absorbing agents can be present in the composition in a co"cel Ill alion range of between about 4%
and about 6% by weight. Of the ultraviolet abso, I i"g agents suit~hle for use herein, benzophenone-3, octyl dimethyl PABA (radi",ale O), Parsol MCX, and mixtures thereof are particularly prerer,-:d.

Another optio"al but pr~rer, ed con~ponent herein is one or more additional chelating agents, preferably in the range of from about Q.02% to about 0.10% by weight, based on the total weight of the col~lposili~ e~er~bly, the chelating agent is ,uresenl in a concentration in the range of between about 0.03% and about 0.07% by weight, based on the total weight of the composilio,~. Among the chelating agents that may be incl~ Iderl in the co"~posilion is teli~so~ ~ EDTA.

Another optional but prerer,ed coi",.)Gnent of the foundation colllposiLiol) is one or more preservatives. The preservative conce"l, alio" in the foundalio,) composition, based on the total weight of that composition, is in the range of between about 0.05% and about 0.8% by weight, preferably between about 0.1% and about 0.3% by weight. Suitable preservatives for use herein include sodium ber,~oa~e and propyl paraben, and mixtures ll ,ereo~.

CA 02239049 l998-05-28 W O 97/20540 PCT~US96/18672 The cosmetic compositions of the present invention can be in the form of foundations, blushers, concealers, compact powders, and the like, ,~re~erably as foundations and concealers.

The table below shows examples of cosmetic compositions of the present invention.

1/% 11/% 111/% IV/% Vl%
A

Cyclomethicone [DC 21330l1 15.2 16.0 14.8 15.315.7 Cyclomethicone/Dimethicone 15.0 16.5 18.5 15.217.25 copolyol [90:10] [DC3225C]1 Mica 0.1 0.15 0.1 0.12 0.1 Titanium Dioxide (Cardre 8.25 9.6 14.2 7.85 8.5 70429)2 Yellowiron oxide 0.55 0.6 0.49 0.590.58 Red ironoxide 0.3 0.25 0.28 0.24 0.4 Black iron oxide 0.1 0.08 0.08 0.120.15 D

Du,dcl~e", 0.1 0.1 0.1 0.1 0.1 W aAellOI 0.3 0.3 0.3 0.3 0.3 Cyclomethicone [DC 21330]1 1 1.5 1 1.2 Thixin R3 0.3 0.3 0.3 0.3 0.3 W O 97/20540 PCT~US96/18672 F

Ethylene Brassylate 0.1 0.1 0.1 0.1 0.1 1/~~ % 111/% ~V/% Vl%
G

Ethanol 4 8 5 6 5 Polyvinylpyrrolidone ~Luviskol 1 1.8 0.8 'i.5 1.2 K 1 7]4 Salicylic acid 1 2 1.5 Dipropylene glycol 10 12 1 1 10 1 1 Glycerine 10 10 9.5 12.5 9.8 Carbowax 400 (PEG 8)5 3.0 2.5 2.8 0 0 Deionised water -- to 100 Na4 EDTA 0.1 0.1 0.1 0.1 0.1 Sodium Citrate 0.30.25 0.25 0.32 0.3 Sodium Chloride 0.3 0.3 0.3 0.3 0.3 1. Supplied by Dow Corning Cor~Gr~liG. .
2. Supplied by Cardre l.)cQr,uo, aled 3. Trihydroxy:,leari, . supplied by NL Chemicals 4. Supplied by BASF

5. Supplied by Union Carbide The formulations of Examples I to V can be p(epared as follows. The various cG~ onel lts listed in the Table have been seyregdled into groups, the co. .sliluents of each group being mixed together before being added to me,..L.er~ of the remaining groups in accord~nce with the procedures set forth below.

In the first step, the mixture of components of phase A is stirred for ap~roxi"~alely 5 minutes with shear mixing until hor,~ogeneous. With high speed shear mixing the materials of phase B are added gradually to A and the batch is mixed for 20 minutes. Phases C and D are added and the resulting mixture is ground until fully dispersed.

W O 97~0540 PCTnJS96/18672 The colT ponents from phase C are then added and the resulting mixture is ground until fully dispersed.

The waxy phase D is then added and the batch is heated to 85~C in a water bath. When the waxes have melted, the batch is removed from the water bath and cooled to 50~C. Phase E premix is then added to the batch and homogenised for 10 minutes. The batch is cooled to room temperature.
Phase F is added and the batch is homogenised for 10 minutes.

The water phase is prepared as follows. The co...poi,ents of phase H are mixed until dissolved. Phase G is prepared by adding PVP to the dipropylene glycol and mixing followed ~y addition with mixing of salicylic acid. Heating may be used if necessary. When most of the powder has dissolved, the glycerine is added to phase G while mixing, followed by addition of the Carbowax. Phase G is cooled and ethanol is added. The solution is mixed until clear. Phase H is added very slowly to phase G and mixed.

The water phase is finally added to the oil phase quickly whilst hor"os~enising at a low speed, with ~lil, ing. When all of the water phase has been added, high shear is applied to the batch for approkimately ~ minutes to increase the viscosily of the final product.

The resulting make-up col.",osilion is ready hr packaging.

The cosMelic c~. ~Iposilio~ ,s of the Examples exhibit anti-acns efficacy, improved product stability and red~ ~cec~ hy~J, c,ge" gas generd~ion.

Claims (21)

What is claimed is:

1. A cosmetic composition in the form of a water-in-oil emulsion comprising:

(a) discontinuous aqueous phase comprising an aqueous or hydroalcoholic solution of acidic skin care active;

(b) continuous oil phase; and (c) pigment which has been coated with organosilicon component selected from a polyorganosiloxane and a silane and mixtures thereof;

characterised in that the aqueous phase has a pH of less than about 6 and the coated pigment has a residual hydride content as measured by hydrogen potential of less than about 2.0 ml H2/g of coated pigment.

2. A cosmetic composition according to Claim 1 wherein the coated pigment has a residual hydride content as measured by hydrogen potential of less than about 1.0, preferably less than about 0.5, especially less than about 0.1 ml H2/g of coated pigment.

3. A cosmetic composition according to Claim 1 or 2 wherein the aqueous phase has a pH of from about 1 to about 5.5 prererably from about 2 to about 5 especially from about 2.5 to about 4.

4. A cosmetic composition according to any of Claims 1 to 3 wherein the polyorganosiloxane is selected from (A) material of the formula:

(R1)3SiO-(Si(R2R3)O)p-Si(R2R3)OA2 wherein p is 1 to 1000 ,oreferably from 1 to 100 A2 is hydrogen or an alkyl group having from 1 to 30 carbon atoms R1 is a C1-C30 alkyl preferably methyl, R2 and R3 are independently selected from a C1-C30 alkyl and a phenyl, preferably wherein R2 and R3 are both methyl or wherein R2 is methyl and R3 is phenyl; or (B) material of the formula:

(R1)3SiO(Si(R2)(H)-O)i-Si(R1)3 wherein i is 1 to 1000, preferably from 1 to 100, and wherein R1 and R2 are as defined above for formula (A).

5. A cosmetic composition according to any of Claims 1 to 3 wherein the silane is selected from material of the formula:

(C) A1SiX1X2X3 wherein A is an alkyl or alkenyl group having from 1 to 30 carbon atoms, and X1, X2 and X3 are independently C1-C4 alkoxy, preferably methoxy or ethoxy, or halo, preferably chloro.

6. A cosmetic composition according to any of Claims 1 to 5 wherein the acidic skin care active is selected from salicylic acid, azelaic acid, retinoic acid, lactic acid, glycolic acid, pyruvic acid, and mixtures thereof.

7. A cosmetic composition according to any of Claims 1 to 6 wherein the acidic skin care active is salicylic acid.

8. A cosmetic composition according to any of Claims 1 to 7 comprising from about 0.1% to about 10%, preferably from about 0.1% to about 5%, more preferably from about 0.5% to about 3%, by weight, of the acidic skin care active.

9. A cosmetic composition according to any of Claims 1 to 8 comprising from about 0.1% to about 25%, preferably from about 1% to about 15%, by weight, of the organosilicon coated pigment.

10. A cosmetic composition according to any of Claims 1 to 9 wherein the pigment is selected from iron oxide and titanium dioxide, and mixtures thereof.

11. A cosmetic composition according to any of Claims 1 to 10 additionally comprising from about 0.1% to about 10%, preferably from about 0.1% to about 5%, more preferably from about 0.5% to about 2%, by weight, of pyrrolidone-based solubilising agent.

12. A cosmetic composition according to Claim 11 wherein the pyrrolidone-based solubilising agent is polyvinylpyrrolidone.

13. A cosmetic composition according to Claims 1 to 12 additionally comprising from about 0.01% to about 5%, by weight, of citric acid or salt thereof.

14. A cosmetic composition according to any of Claims 1 to 13 comprising from about 1% to about 50%, by weight, of volatile silicone oil selected from volatile silicones, non-volatile silicones and mixtures thereof.

15. A cosmetic composition according to Claim 14 wherein the volatile silicone oil is selected from cyclic polyorganosiloxanes having viscosities of no greater than about 10 centistokes, and linear polyorganosiloxnes having viscosities of less than about 5 centistokes at 25°C, and mixtures thereof.

16. A cosmetic composition according to Claim 15 wherein the volatile silicone oil is selected from cyclic polydimethylsiloxanes containing an average of from about 3 to about 9 silicon atoms, preferably from about 4 to about 5 silicon atoms and linear polydimethylsiloxanes containing an average of from about 3 to about 9 silicon atoms.

17. A cosmetic composition according to Claim 16 wherein the polydiorganosiloxane-polyoxyalkylene copolymer is dimethicone copolyol.

18. A cosmetic composition according to any of Claims 1 to 17 additionally comprising from about 0.1% to about 30%, preferably from about 1% to about 10%, by weight, of humectant.

19. A cosmetic composition according to Claim 18 wherein the humectant is glycerine.

20. A cosmetic composition according to Claim 14 comprising from about 0.1% to about 10%, preferably from about 2% to about 5%, by weight, of non-volatiie silicones.

21. A cosmetic composition according to any of Claims 1 to 20 comprising from about 20% to about 95%, preferably from about 40%
to about 80%, by weight, of the oil phase, and from about 5% to about 80%, preferably from about 20% to about 60%, by weight, of the water phase.