EP3773928A1

EP3773928A1 - Water-resistant cosmetic composition

Info

Publication number: EP3773928A1
Application number: EP19720934.9A
Authority: EP
Inventors: Clémentine Champagne
Original assignee: Coatex SAS
Current assignee: Coatex SAS
Priority date: 2018-03-29
Filing date: 2019-03-28
Publication date: 2021-02-17
Also published as: US20210161775A1; WO2019185999A1; CN111867682A; CN111867682B; FR3079415B1; KR20200138361A; FR3079415A1

Abstract

The invention relates to a cosmetic composition in the form of an emulsion which is water-resistant due to the use of an emulsifying polymer. This polymer is prepared by polymerisation of an anionic monomer and a C₁-C₇ unsaturated carboxylic acid ester. The cosmetic composition according to the invention is free of film-forming agent and surfactant compound. The invention also relates to the preparation and the use of this cosmetic composition.

Description

COSMETIC COMPOSITION WATER RESISTANT DESCRIPTION

The invention relates to a cosmetic composition in the form of an emulsion which is resistant to water through the use of an emulsifying polymer. This polymer is prepared by polymerizing an anionic monomer and a C ₁ -C ₇ ester of an unsaturated carboxylic acid. The cosmetic composition according to the invention is free of film-forming agent and surfactant compound. The invention also relates to the preparation and use of this cosmetic composition.

Numerous cosmetic compositions are known, in particular cosmetic compositions in the form of an oil-in-water emulsion for which a lipophilic phase is dispersed in a hydrophilic phase. These cosmetic compositions known in the emulsion form require the use of a surfactant during their preparation.

Such emulsions must be stable and have a texture specific to each use and that makes them effective and pleasant to the touch. These cosmetic compositions must also be easy to apply.

Furthermore, many known cosmetic compositions include film-forming agents which are usually polymers, for example poly (vinylpyrrolidone / eicosene) copolymers, polyurethaneacrylate-octylacrylamide copolymers, polyurethanes or acrylate copolymers. Generally, these film-forming agents make it possible to obtain a water-resistant film after application of the cosmetic composition.

Nevertheless, such film-forming agents generally lead to films that are tacky to the touch or that provide a greasy or waxy feel to the touch. After application, the film must be regular and homogeneous. It must be durable, especially to avoid the proliferation of applications too often, while being sufficiently fine, especially not to provide discomfort.

After application of a cosmetic composition, the film applied should be resistant to water, in particular to limit or avoid leaching phenomena due to moisture. The water resistance also makes it possible to maintain longer and more effectively after application the other ingredients of the cosmetic composition, in particular the active or moisturizing ingredients present within the composition. Moreover, the methods for preparing known cosmetic compositions which use surface-active compounds lead to compositions which, after application, produce a film in which the surface-active compound limits the water resistance of these compositions. Indeed, in the presence of moisture, the surfactant compound can produce an emulsion recovery phenomenon which makes the composition leachable. The stability of these cosmetic compositions can therefore be impaired due to the presence of a surfactant compound.

US 2005 0186169 discloses a cosmetic method of anti-wrinkle treatment. This process is based on the use of a film-forming polymer that acts on the tension of the skin. The document WO 2014 139901 relates to solar formulations with improved thickening and waterproofing properties. These formulations comprise a styrenic polymer. CA 2208870 discloses a cosmetic or pharmaceutical composition comprising at least one film-forming polymer providing an improvement in leaching resistance. US 2011 0073126 relates to monophasic aqueous cosmetic nail varnish compositions which are resistant to transfer. They comprise a water-soluble film-forming copolymer and a plasticizer copolymer. EP 1291001 discloses a shampoo composition comprising a crosslinked thickening copolymer of methacrylic acid and C ₄ alkyl acrylate and an oil.

The article Synthesis, characterization, and rheological studies of methacrylic acid-ethyl acrylate-diallyl phthalate copolymers (Manjeet Jassal, Badri Narayan Acharya, Pushpa Bajaj, Journal of Applied Polymer Science, 19 May 2003) concerns a study of synthesis, characterization and rheology of crosslinked terpolymers thickeners. In general, the cosmetic compositions comprise a very large number of ingredients. The reduction of the number of ingredients while retaining the properties of the cosmetic compositions during their use, but also during their preparation, is constantly sought.

All of these properties are particularly sought after for cosmetic sunscreen compositions, especially because of their usual use in humid conditions. It is the same for makeup cosmetic compositions, especially for mascara compositions and for foundation compositions.

There is therefore a need for improved cosmetic compositions as well as methods for preparing or using such cosmetic compositions which are also improved. The cosmetic composition according to the invention makes it possible to provide a solution to all or part of the problems of the cosmetic compositions of the state of the art.

Thus, the invention provides a cosmetic composition in the form of an emulsion, resistant to water, free of film-forming agent and surfactant compound, and comprising:

Particles of a lipophilic phase comprising at least one lipophilic compound, dispersed in:

A hydrophilic continuous phase having a pH greater than or equal to 6.5 and comprising: at least one hydrophilic compound and

at least one emulsifying polymer (P) prepared by at least one polymerization reaction:

(a1) at least one anionic monomer comprising at least one polymerizable olefinic unsaturation and at least one carboxylic acid function or a salt thereof and

(a2) at least one ester Ci-C ₇ of a compound derived from an acid selected from acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid and crotonic acid.

Within the composition according to the invention, the amounts of lipophilic phase and of hydrophilic phase may vary, in particular according to the desired texture or according to the final use of the composition.

Preferably, the composition according to the invention comprises from 0.1 to 75% by weight or from 1 to 75% by weight of dispersed lipophilic phase, relative to the total amount by weight of continuous hydrophilic phase and of dispersed lipophilic phase . Also preferably, the composition according to the invention comprises from 0.1 to 70% by weight or from 1 to 70% by weight of dispersed lipophilic phase, relative to the total amount by weight of continuous hydrophilic phase and of lipophilic phase dispersed.

More preferably, the composition according to the invention comprises from 0.1 to 65% by weight or from 1 to 65% by weight of dispersed lipophilic phase, relative to the total amount by weight of continuous hydrophilic phase and lipophilic phase dispersed. Also more preferably, the composition according to the invention comprises from 0.1 to 60% by weight or from 1 to 60% by weight of dispersed lipophilic phase, relative to the total amount by weight of continuous and phase hydrophilic phase lipophilic dispersed. The cosmetic composition according to the invention comprises at least one lipophilic compound in the form of particles to form the lipophilic phase. Preferably, the lipophilic compound is a compound for cosmetic use.

In a preferred manner according to the invention, the lipophilic phase comprises at least one lipophilic compound chosen from fatty acids, fatty alcohols, butters, waxes (for example beeswaxes), oils, preferably a chosen oil. among mineral oils (eg paraffin oil, liquid petrolatum, mineral oils with a boiling point of 300 to 400 ° C), animal oils (eg squalenes, squalane, perhydrosqualene), vegetable oils (eg sweet almond oil, calophyllum oil, palm oil, apricot kernel oil, avocado oil, jojoba oil, olive oil, castor oil, cereal germ oils, liquid shea butter fraction), unsaponifiable compounds from natural oils, synthetic oils (eg polyisobutene hydrogenated esters of fatty acids such as purcellin oil, butyl myristate , isopropyl myristate, cetyl myristate, isopropyl palmitate, butyl stearate, hexadecyl stearate, isopropyl stearate, octyl stearate, isocetyl stearate, oleate decyl, hexyl laurate, propylene glycol dicaprylate, esters derived from lanolic acid such as dispropyl lanolate, isocetyl lanolate, acetylglycerides, alcohol octanoates, polyalcohols octanoates, decanoates of alcohol, polyalcohols decanoates, especially glycol octanoates, glycerol octanoates, glycol decanoates, glycerol decanoates, alcohol ricinoleates, polyalcohols ricinoleates), terpenes, polyterpenes, phytosterol silicone oils (for example cyclomethicones, low molecular weight polydimethylsiloxanes or silicone oils, high molecular weight polydimethylsiloxanes or silicone gums, polymethylsiloxines) ethers, dimethiconols, phenylated polydimethylsiloxanes, low molecular weight siloxanols, high molecular weight siloxanols, trimethylsiloxysilicates), fluorinated oils (e.g., fluorinated perfluoroethers and fluorinated silicones).

In the composition according to the invention, the lipophilic phase is dispersed within the hydrophilic phase which comprises at least one hydrophilic compound. In a preferred manner according to the invention, the hydrophilic compound is chosen from water alone or as a mixture with at least one compound chosen from among glycerol, polyglycerols, glycols, for example propylene glycol, butylene glycol, humectant compounds, for example humectant compounds for composition cosmetics, derivatives of sugars, for example xylytol, maltilol. Preferably, the composition according to the invention has a pH greater than 4, more preferably greater than 5 and much more preferably greater than 6.

Also preferably, the composition according to the invention has a pH of less than 13, more preferably less than 12 and much more preferably less than 11.

Also preferably, the composition according to the invention has a pH ranging from 4 to 13 or from 4 to 12 or from 4 to 11, more preferably from 5 to 13 or from 5 to 12 or from 5 to 11 and much more preferably ranging from 6 to 13 or from 6 to 12 or from 6 to 11.

In an essential manner according to the invention, the hydrophilic continuous phase comprises at least one hydrophilic compound and at least one emulsifying polymer (P) prepared by at least one polymerization reaction of the monomers (a1) and (a2). Although having an emulsifying character, the polymer (P) according to the invention is not a surfactant compound.

The polymer (P) used according to the invention is known as such. It may be prepared by known methods, in particular a radical polymerization reaction, for example an emulsion, dispersion or solution polymerization reaction. The polymerization may be conducted in a solvent, in the presence of at least one initiator compound. As examples of initiator compounds, it is possible to use at least one compound chosen from azo initiator compounds (for example azobisisobutyronitrile), a peroxide compound, preferably hydrogen peroxide, benzoyl peroxide, benzoyl hydroperoxide and mixtures thereof. . Mention may also be made of alkali metal persulfates, in particular sodium persulfate and potassium persulfate, ammonium persulfate, partially water-soluble peroxides, in particular succinic peracid, t-butyl hydroperoxide and cumyl hydroperoxide. persulfates associated with a cuprous ion, a ferrous ion, a sulphite ion or a bisulphite ion and mixtures thereof.

In addition to the various monomers, the method for preparing the polymer (P) generally employs at least one chain transfer agent, preferably chosen from mercaptan compounds, in particular mercaptan compounds comprising at least four carbon atoms, such as butyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, iron / -dodecyl mercaptan, isooctyl 3-mercaptopropionate. Preferably, the reaction is a radical emulsion polymerization reaction.

According to the invention, the initiator compound or radical generator can therefore be associated with at least one controlled radical polymerization transfer agent, in particular a Raft transfer agent (reversible addition-fragmentation chain transfer or controlled radical polymerization controlled by reversible chain transfer by addition-fragmentation).

In a preferred manner according to the invention, the monomer (a1) is chosen from acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, crotonic acid, a sodium salt and the like. acrylic acid, a methacrylic acid salt, a maleic acid salt, a maleic anhydride salt, an itaconic acid salt, a crotonic acid salt, and combinations thereof. More preferably, the monomer (a1) is selected from acrylic acid, a salt of acrylic acid, methacrylic acid, a salt of methacrylic acid and combinations thereof.

Preferably according to the invention, the monomer (a2) is an ester Ci-C ₆ or a C4 ester. Also preferably according to the invention, the monomer (a2) is a C 1 -C 7 ester of acrylic acid or a C ₁ -C ₇ ester of methacrylic acid, more preferentially chosen from methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, ethylhexyl methacrylate, and combinations thereof. More preferably, the monomer (a2) is selected from ethyl acrylate, butyl acrylate, methyl methacrylate and combinations thereof.

In a particularly preferred manner according to the invention, the monomer (a1) is chosen from acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, crotonic acid, a sodium salt and the like. acrylic acid, a methacrylic acid salt, a maleic acid salt, a maleic anhydride salt, an itaconic acid salt, a crotonic acid salt and combinations thereof, more preferably acrylic acid or methacrylic acid; and the monomer (a2) is an ester Ci-C ₆ or a C1-C4 ester or ester is a C ₇ -C acrylic acid ester or a Ci-C ₇ of methacrylic acid, preferably chosen from methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, ethylhexyl methacrylate and combinations thereof , more preferably ethyl acrylate, butyl acrylate, methyl methacrylate and combinations thereof.

Also preferably, the polymerization reaction uses:

20 to 70 mol% or 30 to 60 mol%, preferably 30 to 55 mol% or 30 to 50 mol%, of monomer (a1) and From 30 to 80 mol% or from 40 to 70 mol%, preferably from 45 to 70 mol% or from 50 to 70 mol%, of monomer (a 2),

relative to the total molar amount of monomers (a1) and (a2).

In addition to monomers (a1) and (a2), the polymer (P) may be prepared from other monomers. Thus, the polymer (P) can be prepared by a polymerization reaction also implementing:

(a3) at least one compound selected from 2-acrylamido-2-methylpropanesulphonic acid, ethoxymethacrylate sulfonic acid, sodium methallylsulfonate, styrene sulfonate hydroxyethylacrylate phosphated, hydroxypropylphosphate phosphated, hydroxyethylhexylphosphate acrylate, hydroxyethyl phosphated methacrylate, hydroxypropyl-phosphatized methacrylate, hydroxyethylhexyl-phosphatized methacrylate, their salts and combinations or (a4) at least one compound selected from hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethylhexyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxyethylhexyl -methacrylate or

(a5) at least one crosslinking monomer or at least one monomer comprising at least two olefinic unsaturations.

Also advantageously according to the invention, the polymerization reaction may employ less than 20 mol%, preferably 0.2 to 20 mol%, in particular 0.5 to 10 mol%, of monomer (a3). relative to the total molar amount of monomers.

Also advantageously, the polymerization reaction may employ less than 20 mol%, preferably 0.2 to 20 mol%, in particular from 0.5 to 10 mol%, of monomer (a4) relative to the total molar amount of monomers.

According to the invention, the monomer (a5) can be chosen from:

A compound of formula (I):

in which :

o L represents CH _2, CH ₂ or CH ₂ monoalkoxylé polyalkoxylated, preferably a CH ₂ CH ₂ monoethoxylated or polyethoxylated where Q represents a direct bond or C (O),

R represents -C (H) = CH ₂ , -C (CH ₃ ) = CH ₂ , -C (H) = C (H) C (O) OH,

wherein Q ³ represents a divalent residue of an asymmetric diisocyanate compound, preferably selected from tolyl-1,3-diisocyanate (TDI) and isophorone diisocyanate (IPDI) and

wherein Q ⁴ represents CH ₂ , CH ₂ -CH ₂ , monoalkoxylated CH _2, monoalkoxylated CH ₂ -CH _2, polyalkoxylated CH ₂ or polyalkoxylated CH ₂ -CH ₂ ;

A compound of formula (P):

in which :

R ³ is independently H or CH ₃ ,

L ¹ independently represents a linear or branched C ₁ -C ₂ o -alkylene group, preferably an ethylene group or a propylene group, and

o p represents independently 0 or an integer ranging from 1 to 30, for example from 1 to 20, in particular from 1 to 15, in particular from 1 to 10.

The monomer (a5) may also be chosen from di (meth) acrylates such as polyalkylene glycol di (meth) acrylate, especially polypropylene glycol di (meth) acrylate, ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 1,6-butylene glycol di (meth) acrylate, di (meth) acrylate, 1,6-hexanediol meth) acrylate, neopentyl glycol di (meth) acrylate, 9-nonanediol di (meth) acrylate, but also 2,2'-bis (4- (acryloxypropyloxyphenyl) propane, 2,2'-bis (4- (acryloxydiethoxyphenyl)) propane and zinc acrylate; tri (meth) acrylate compounds such as trimethylolpropane tri (meth) acrylate and ethoxylated trimethylolpropane tri (meth) acrylate, tri (meth) acrylate trimethylol ethane, tri (meth) acrylate pentaerythritol and tri (meth) acrylate tetramethylolmethane; tetra (meth) acrylate compounds such as ditrimethylolpropane tetra (meth) acrylate, tetra (meth) acrylate, tetramethylolmethane and pentaerythritol tetra (meth) acrylate; hexa (meth) acrylate compounds such as dipentaerythritol hexa (meth) acrylate; penta (meth) acrylate compounds such as dipentaerythritol penta (meth) acrylate; allyl compounds such as allyl (meth) acrylate, diallylphthalate, diallyl itaconate, diallyl fumarate, diallyl maleate; polyallyl sucrose ethers having 2 to 8 groups per molecule, polyallyl pentaerythritol ethers such as pentaerythritol diallyl ether, pentaerythritol triallyl ether and pentaerythritol tetraallyl ether; polyallyl ethers of trimethylolpropane such as diallyl trimethylolpropane ether and triallyl trimethylolpropane ether. Other polyunsaturated compounds include divinyl glycol, divinyl benzene, divinylcyclohexyl and methylenebisacrylamide.

The monomer (a5) may also be prepared by an esterification reaction of a polyol with an unsaturated anhydride such as acrylic anhydride, methacrylic anhydride, maleic anhydride or itaconic anhydride. To obtain the monomer (a5), it is also possible to use compounds chosen from polyhaloalkanols such as 1,3-dichloroisopropanol and 1,3-dibromoisopropanol; haloepoxyalkanes such as epichlorohydrin, epibromohydrin, 2-methyl epichlorohydrin and epiiodohydrin; polyglycidyl ethers such as 1,4-butanediol diglycidyl ether, glycerin-1,3-diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, polypropylene glycol diglycidyl ether, bisphenol A-epichlorohydrin epoxy resin and mixtures.

The monomer (a5) may also be chosen from trifunctional crosslinking agents. It may be in particular trimethylolpropane tri (meth) acrylate (TMPTA) or ethoxylated trimethylolpropane tri (meth) acrylate (such as for example TMPTA 30E). The monomer (a5) may also be selected from trimethylolpropane tri (meth) acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, ethylene glycol di (meth) acrylate, methylenebisacrylamide, diallyl phthalate, diallyl maleate and mixtures thereof.

The monomer (a5) may also be a mixture of two different monomers, for example EGDCPEA (ethylene glycol dicyclopentenyl ether acrylate) and TMPTA or else EGDCPEA and TMPTA 30E or else EGDCPEMA (ethylene glycol dicyclopentenyl ether methacrylate) and TMPTA or EGDCPEMA and TMPTA 30E.

According to the invention, the monomer (a5) is preferably chosen from a compound of formula (I), a compound of formula (II), trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, ethoxylated trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane triacrylate, ethylene glycol dimethacrylate, ethylene glycol diacrylate, methylenebisacrylamide, diallylphthalate, diallyl maleate and mixtures thereof.

Also advantageously, the polymerization reaction may involve less than 5 mol%, preferably 0.01 to 4 mol%, in particular 0.02 to 4 mol% or 0.02 to 2 mol%, in particular from 0.02 to 1 mol%, of monomer (a5) relative to the total molar amount of monomers.

Preferably, the polymer (P) is prepared from the only monomers (a1) to (a5), in particular from the combinations of the only monomers (a1) - (a2), (a1) - (a2) - ( a3), (a1) - (a2) - (a4), (a1) - (a2) - (a5), (a1) - (a2) - (a3) - (a4), (a1) - (a2) - (a3) - (a5), (a1) - (a2) - (a4) - (a5), (a1) - (a2) - (a3) - (a4) - (a5). The polymer (P) does not then comprise linear or branched (meth) acrylate (EO) _n -C-C 32 -alkyl monomer comprising n ethoxylated groups, n ranging from 1 to 150. In particular, it does not comprise monomer methacrylate-œ25 -C 1 ₆ / C _{8 January} linear alkyl.

More preferably, the polymer (P) is prepared from monomers (a1) and (a2) alone or from monomers (a1), (a2) and (a5) alone.

Advantageously according to the invention, the polymerization reaction uses:

From 19.9 to 66 mol% or from 29.8 to 66 mol%, preferably from 29.8 to 53 mol% or from 29.8 to 49 mol%, of monomer (a1),

From 30 to 80 mol% or from 40 to 70 mol%, preferably from 45 to 70 mol% or from 50 to 70 mol%, of monomer (a 2),

From 0.01 to 4 mol% or from 0.02 to 4 mol%, preferably from 0.02 to 2 mol% or from 0.02 to 1 mol%, of monomer (a5),

relative to the total molar amount of these three monomers.

In a preferred manner according to the invention, the polymer (P) may be totally or partially neutralized, preferably by means of at least one compound selected from among NaOH, KOH, ammonium derivatives, ammonia, amine bases, for example triethanolamine, aminomethylpropanol or 2-amino-2-methyl-propanol (AMP) and combinations thereof

Also preferably according to the invention, the polymer (P) may be totally or partially coacervated, more preferably: by reducing the pH of the dispersion (D), for example by reducing the pH to a value of less than 6.5, in particular by means of an acidic compound, in particular by means of at least one organic acid or mineral compound , in particular an acidic compound selected from phosphoric acid, citric acid, glucono-lactone, lactic acid, salicylic acid, glycolic acid, ascorbic acid, glutamic acid, hydrochloric acid, acetic acid, D-gluconic acid, sulphonic acid, methanesulfonic acid , benzimidazolesulfonic acid, tartaric acid, 4-aminobenzoic acid, benzoic acid, sorbic acid, phenylbenzimidazole sulfonic acid, benzylidene camphor sulfonic acid, terephthalylidene dicamphor sulfonic acid or

by increasing the ionic strength of the dispersion (D), for example by adding at least one ionized compound or at least one salt, in particular NaCl, KCl, MgCl ₂ , CaCl ₂ , MgSO ₄ , CaSO ₄ .

Within the composition according to the invention, the amount of polymer (P) present within the hydrophilic phase may vary. Preferably, the composition according to the invention comprises from 0.4 to 10% by weight, from 0.4 to 9% by weight or from 0.4 to 8% by weight, preferably from 0.5 to 10% by weight. by weight, from 0.5 to 9% by weight or from 0.5 to 8% by weight or else from 0.6 to 10% by weight, from 0.6 to 9% by weight or from 0.6 to 8% by weight % by weight of polymer (P) relative to the amount of hydrophilic phase.

In addition to the lipophilic and hydrophilic phases, the composition according to the invention may comprise other substances, in particular other substances for cosmetic use. In a preferred manner according to the invention, the composition also comprises at least one substance chosen from mineral particles (for example particles of titanium dioxide, iron oxide particles, particles of zinc oxide), particles coated minerals, in particular coated with a hydrophobic compound, for example stearic acid (for example particles of titanium dioxide coated with a hydrophobic compound, for example stearic acid), an organic sunscreen ( for example selected from avobenzone, ethylhexyltriazone, benzophenone-3, octocrylene, benzophenone-2, benzophenone-4, ethylhexylsalicylate, 4-methylbenzylidene camphor, octyl-N, N-dimethyl PABA (para-aminobenzoic acid), ethylhexyl dimethyl PABA, ethylhexyl methoxycinnamate , isoamyl methoxycinnamate, butyl methoxydibenzoylmethane, diethylamino hydroxybenzoyl hexyl benzoate, bis-ethylhexyloxyphenol methoxyphenyl triazine, drometrizole trisiloxane, methylene bis-benzotriazolyl tetramethylbutylphenol, diethylhexyl butamido triazone, ethylhexyl triazone, isoamyl p-methoxycinnamate, polysilicon-15, tris biphenyl triazine, homomenthyl salicylate, PEG-25 PABA), lipophilic cosmetic active molecules, water-soluble cosmetic active molecules.

The polymer (P) used according to the invention is not a surfactant compound. A surfactant compound acts by forming a monolayer at the water-oil interface reducing the surface tension of the lipophilic compound particles. This surfactant compound forms micelles. For this, a molecule of surfactant compound comprises two distinct parts: a lipophilic part and a hydrophilic part.

Advantageously according to the invention, the polymer (P) makes it possible to control the texture and the stability of the emulsion according to the invention. It also allows the composition according to the invention to remain on the surface of the skin after its application, despite the presence of water, for example in case of leaching or during the presence of sweat. During its application, the cosmetic composition according to the invention forms a thin layer of lipophilic compound on the surface of the skin. This property is accessible in the absence of any film-forming agent. The composition according to the invention then has good water resistance.

Advantageously, the composition according to the invention can be implemented within a formulation. The invention therefore also relates to a formulation comprising at least one cosmetic composition according to the invention. Preferably, the formulation according to the invention is chosen from a sun protection formulation, a makeup formulation, a skin care formulation and a hair care formulation. In addition to the cosmetic composition according to the invention and this formulation, the invention also relates to the preparation of the cosmetic composition according to the invention. Thus, the invention provides a method for preparing a cosmetic composition in the form of an emulsion, water-resistant, free of film-forming agent and surfactant compound, and comprising:

The preparation of a hydrophilic continuous phase comprising:

at least one hydrophilic compound having a pH greater than or equal to 6.5 and at least one emulsifying polymer (P) prepared by at least one polymerization reaction: (a1) at least one anionic monomer comprising at least one polymerizable olefinic unsaturation and at least one carboxylic acid function or a salt thereof and

(a2) at least one ester Ci-C ₇ of a compound derived from an acid selected from acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid and crotonic acid,

The preparation of a hydrophilic continuous phase comprising at least one lipophilic compound, and then

The addition, with stirring and in the absence of surfactant compound, of the lipophilic phase in the hydrophilic phase.

In a particularly advantageous manner according to the invention and thanks to the emulsifying nature of the polymer (P), the cosmetic composition is prepared in the absence of surfactant compound usually used in the preparation of oil-in-water type compositions. of the state of the art.

Preferably, the addition is carried out at a temperature ranging from 10 to 90 ° C or from 15 to 75 ° C or at room temperature.

Also preferably, the preparation method according to the invention also comprises adjusting the final pH of the composition. Preferably, the pH is adjusted to a value ranging from 4 to 13 or from 4 to 12 or from 4 to 11. More preferably, the pH is adjusted to a value ranging from 5 to 13 or from 5 to 12 or from 5 to 11. More preferably, the pH is adjusted to a value ranging from 6 to 13 or from 6 to 12 or from 6 to 11.

During the preparation of the cosmetic composition according to the invention, the addition of the lipophilic phase in the hydrophilic phase is carried out with stirring, preferably with stirring using a device producing a shear rate of less than 5000 s ¹ .

According to the invention, the particular, advantageous or preferred characteristics of the cosmetic composition according to the invention define preparation methods according to the invention which are also particular, advantageous or preferred.

Furthermore, the invention also relates to a method for improving the water resistance of a cosmetic composition in the form of an emulsion, free of film-forming agent and surfactant compound, comprising the addition in the cosmetic composition of at least one emulsifying polymer (P) prepared by at least one polymerization reaction: (a1) at least one anionic monomer comprising at least one polymerizable olefinic unsaturation and at least one carboxylic acid function or a salt thereof and

According to the invention, the particular, advantageous or preferred characteristics of the cosmetic composition according to the invention define methods for improving the water resistance of a cosmetic composition according to the invention which are also particular, advantageous or preferred .

The invention also provides a cosmetic treatment method by means of a cosmetic composition according to the invention or by means of a formulation according to the invention or else by means of a composition prepared according to the method of preparation of a cosmetic composition according to the invention. The cosmetic treatment method according to the invention comprises the application, in particular the application on the skin, of a composition or of this formulation according to the invention.

During its implementation, in particular according to the cosmetic treatment method according to the invention, the cosmetic composition according to the invention makes it possible to obtain an applied layer or an applied film which is resistant to water. Such water resistance is particularly advantageous when the cosmetic composition according to the invention is applied to the skin.

According to the invention, the particular, advantageous or preferred characteristics of the cosmetic composition according to the invention define cosmetic treatment methods according to the invention which are also particular, advantageous or preferred.

EXAMPLES

The following examples illustrate the various aspects of the invention. The following abbreviations are used:

• AMA: methacrylic acid,

• AE: ethyl acrylate,

• diallyl phthalate (DAP),

Polyglykol B 11/50 from Clariant: ethylene oxide-propylene oxide-monobutyl ether, • Empicol LXVN from Huntsmann: sodium lauryl sulphate (SLS),

• Texapon NSO from BASF: 28% ammonium laureth sulfate solution or 28% ammonium lauryl ether sulfate solution (SLES),

Sodium persulfate (NH ₄ ) ₂ S ₂ O ₈ ,

• methacrylate (C _l6 / C _l8 and linear ethoxylated 25 times alkyl) (monomer (x)).

EXAMPLE 1 Preparation of Polymers (PI) According to the Invention and Comparative PCI in a Semi-Hatch Process

In a 1 L reactor stirred and heated with an oil bath, the mixture is prepared

1 by introducing deionized water and a solution of sodium lauryl sulphate (SLS) or an aqueous solution containing 28% by weight of sodium lauryl ether sulphate (SLES), and optionally ethylene oxide-propylene oxide-monobutyl ether ( B 11/50).

In a beaker is prepared a mixture 2 called said pre-mixture of monomers, comprising in deionized water:

• monomer (a1), methacrylic acid (AM A),

• monomer (a2), ethyl acrylate (AE),

• monomer (a5), diallyl phthalate,

Optionally monomeric (x),

Optionally 28% solution of sodium lauryl ether sulphate (SLES) or sodium lauryl sulphate (SLS),

• optionally an associative monomer (s), methacrylate-œ25 _Ci-6 / C _l8 linear alkyl.

This premix is stirred to form a monomeric mixture.

An initiator solution comprising ammonium persulfate and deionized water is prepared. All reagents and quantities used are presented in Table 1.

In the reactor heated to a temperature of 85 ° C. ± 1 ° C., injection is carried out in parallel during

2 hours, the initiator solution and the premix of monomers. The mixture is baked for 30 minutes at a temperature of 85 ° C. ± 1 ° C. The whole is then cooled to room temperature.

The polymers according to the invention and comparative were prepared under these conditions by varying the monomer compositions of the premixes of monomers. The compositions of the copolymers obtained are shown in Table 1.

Table 1

Example 2 Preparation and Evaluation of Cosmetic Compositions (Cl to C8) According to the Invention and Comparative (CCI to CC8)

In a beaker, the hydrophilic phase is prepared by mixing, with stirring by means of a paddle stirrer and motor Dca or Rayneri, deionized water and a polymer (P1) according to the invention or a polymer (PC1) comparative or comparative polymers of the state of the art. The pH is adjusted to a value of 7 by adding a 20% sodium hydroxide solution in water (at a pH value of 5.5 for the compositions CC6 and CC8).

The hydrophilic phase of the compositions according to the invention and comparative compositions is prepared with stirring at 700-1000 rev / min (except for the composition CC8 at 1600-2000 rev / min).

Comparative polymers are the polymer (PC1) of Example 1 and the comparative polymers of the state of the art:

Polymer (PC2): Pemulen TR1 (Lubrizol - INCI: acrylates / Cio-30 alkyl acrylate crosspolymer), • Polymer (PC3): Rheomer SC Plus (Solvay - INCI: acrylates / beheneth-25 methacrylate copolymer).

The comparative composition (CC1) comprises polymer (P1) according to the invention and a surfactant compound (Emulium Delta Gattefossé - INCI: cethyl alcohol (and) glyceryl stearate (and) PEG75 stearate (and) ceteth-20 (and) steareth-20) while the comparative composition (CC8) does not include a polymer and comprises a surfactant compound (Emulium Delta Gattefossé).

The lipophilic compounds of the lipophilic phase are:

• Caprylis (INCI: caprylic / capric triglyceride),

• commercial hydrogenated sunflower oil (INCI: Helianthus annuus (sunflower) seed oil),

• commercial liquid paraffin (INCI: Paraffinum liquidum),

• Floramac 10 (Floratech - INCI: Ethyl macadamia),

• Gransil GMD-3 (Grant Industries - INCI: Dimethicone & Polysilicone-1).

The ingredients and amounts are detailed in Tables 2 and 3, as well as the characteristics and properties of the cosmetic compositions prepared. The compositions are stable after 1 month at 40 ° C after being evaluated visually by lack of partial separation of the lipophilic phase dispersed at the surface of the hydrophilic phase.

Brookfield viscosity is measured at 20 rpm and 25 ° C.

To measure the size distribution of the dispersed lipophilic phase particles (D50 in%) within the hydrophilic phase, a Mastersizer 2000 Malvern apparatus is used. D50% is the size at which 50% of the particle volume is smaller than this particular value.

To evaluate the water resistance of the cosmetic compositions, the Leneta contrast map is spread on the composition using a shim of 300 μm and then allowed to dry for 24 hours. Then, a few drops of deionized water are deposited on the composition film. If the composition film becomes whitish, a redispersion phenomenon occurs which shows that the cosmetic composition is not stable. On the contrary, the absence of a color change demonstrates the stability of the cosmetic composition.

Table 2

Table 3

Thus, the polymer (P1) according to the invention makes it possible to prepare water-resistant cosmetic compositions after application.

On the other hand, the comparative polymer (PC1) comprising the monomer (x) does not make it possible to obtain a cosmetic composition that is water-resistant after application. Similarly, Comparative polymers known (PC2) and (PC3) do not make it possible to obtain a cosmetic composition that is water-resistant after application.

Finally, the use of a surfactant compound in the comparative cosmetic compositions, with or without a polymer (P1) according to the invention, does not make it possible to obtain a water-resistant cosmetic composition after application.

Example 3 Preparation and Evaluation of a Sun Protection Formulation

according to the invention

A mixture 1 is prepared comprising:

2,2 ', 2 ", 2" - (ethane-1,2-diyldinitrilo) -tetraacetic acid (EDTA) (0.2 g),

• potassium sorbate (0, 1 g) and

• water (63.8 g).

A mixture 2 is prepared by adding to the mixture 1, the polymer (P1) according to the invention (1.2 g) and a commercial rheology modifying agent (Rheostyl 90 N Coatex) (0.7 g). The pH is adjusted by addition with stirring (700-1000 rev / min) of sodium hydroxide 10% by weight in water (1 g).

A mixture 3 is prepared comprising:

• liposoluble organic UVA filter (Uvinul A Plus Granular BASF) (2 g),

• liposoluble organic UVB filter (Eusolex 2292 Merck KGaA) (6g),

• liposoluble organic broad spectrum UV filter (Tinosorb S BASF) (3 g) and

• emollient (Cetiol B BASF) (4 g).

A mixture 4 is prepared comprising:

• water soluble organic UVB filter (Parsol HS DSM) (2.5 g) and

• deionized water (15 g).

In the mixture 2 stirred, the mixture 3 is added and then a preservative (phenoxyethanol) (0.5 g).

The formulation (Fl) of sun protection according to the invention is obtained, the pH of which is 6.7. It has a sun protection factor of 30, evaluated from a simulator (BASF Sunscreen Simulator via www.sunscreensimulator.basf.com).

Its resistance to water is 91%.

This water resistance is determined in vitro by measuring the evolution of the sun protection factor according to a spectrophotometric method (Kontron UV spectrophotometer, equipped with an integrating sphere and a monochromator, capable of delivering a UV energy flux between 290 and 400 nm) by measuring the flow of UV energy passing through the formulation, expressed in energy transmission, and comparison of this flux with the initial flow. Source and support are also taken into account.

On a support (plates of PMMA Sunplates - Helioscience), one spreads the formulation (Fl) with plastic syringes of laboratory or with a pipette with capillary and piston (Microman 250 pL Gilson) in order to realize a homogeneous film of 1.3 mg / cm ² approximately.

Once the formulation is dried, the support is placed in a stream of thermostatically controlled water (29 ° C.) by a water bath equipped with an adjustable flow water circulation pump (Ika). Water is circulated (3 L / min) on the support for 15 minutes.

Then, the support is dried and the measurements are made using the spectrophotometer. The sun protection factor (PF in vitro) is expressed from the entire residual UVB and UVA spectrum that has passed through the same formulation layer as that spread on the skin and corrected according to a spectral characteristic of the sun. the reactivity of the skin as a function of the wavelength.

The average protection index of the preparation studied was obtained by calculating the arithmetic mean of the protection indices of several tests. Water resistance is the ratio of SPF in vitro before and after bathing; it must be greater than or equal to 50% for the formulation to be considered water resistant.

The 91% result clearly demonstrates the very good water resistance of this oil-in-water type solar formulation prepared solely by means of the emulsifying polymer (P1).

Claims

A cosmetic composition in the form of an emulsion, resistant to water, free of film-forming agent and surfactant compound, and comprising:

2. Composition according to claim 1 comprising from 0.1 to 75% by weight or from 1 to 75% by weight, preferably from 0.1 to 70% by weight or from 1 to 70% by weight, more preferably from 0 to 75% by weight. From 1 to 65% by weight or from 1 to 65% by weight, also more preferably from 0.1 to 60% by weight or from 1 to 60% by weight, of the dispersed lipophilic phase, relative to the total amount by weight continuous hydrophilic phase and dispersed lipophilic phase.

3. Composition according to one of claims 1 or 2 wherein the lipophilic phase comprises at least one lipophilic compound selected from fatty acids, fatty alcohols, butters, waxes (for example beeswax), oils , preferably an oil chosen from mineral oils (for example paraffin oil, liquid petroleum jelly, mineral oils having a boiling point ranging from 300 to 400 ° C.), oils of animal origin ( eg squalenes, squalane, perhydrosqualene), vegetable oils (eg sweet almond oil, calophyllum oil, palm oil, apricot kernel oil, oil avocado, jojoba oil, olive oil, castor oil, cereal germ oils, liquid shea butter fraction), unsaponifiable compounds from natural oils, synthetic oils (for example hydrogenated polyisobutene, fatty acid esters such as purcellin oil, butyl myristate, isopropyl myristate, cetyl myristate, palmitate). isopropyl, butyl stearate, hexadecyl stearate, isopropyl stearate, octyl stearate, isocetyl stearate, decyl oleate, hexyl laurate, propylene glycol dicaprylate, esters lanolic acid derivatives such as dispropyl lanolate, isocetyl lanolate, acetylglycerides, alcohol octanoates, polyalcohol octanoates, alcohol decanoates, polyalcohols decanoates, especially glycol octanoates, glycerol octanoates, glycol decanoates, glycerol decanoates, ricinoleates of alcohols, polyalcohols ricinoleates), terpenes, polyterpenes, phytosterol, silicone oils (for example cyclomethicones, low molecular weight polydimethylsiloxanes or silicone oils, high molecular weight polydimethylsiloxanes or silicone gums, polymethylsiloxanes, dimethiconols, phenylated polydimethylsiloxanes, low molecular weight siloxanols, high molecular weight siloxanols, trimethylsiloxysilicates), fluorinated oils (for example fluorinated perfluoroethers and fluorinated silicones).

4. Composition according to one of claims 1 to 3 wherein the hydrophilic compound is selected from water alone or in admixture with at least one compound selected from glycerol, polyglycerols, glycols, for example propylene glycol, butylene glycol, humectant compounds, by example of humectant compounds for cosmetic composition, derivatives of sugars, for example xylytol, maltilol.

5. Composition according to one of claims 1 to 4 having:

A pH greater than 4, preferably greater than 5, more preferably greater than 6 or

A pH less than 13, preferably less than 12, more preferably less than 11 or

A pH ranging from 4 to 13 or from 4 to 12 or from 4 to 11, preferably from 5 to 13 or from 5 to 12 or from 5 to 11, more preferably from 6 to 13 or from 6 to 12 or from 6 to 11.

6. Composition according to one of claims 1 to 5 for which: The monomer (a1) is chosen from acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, crotonic acid, a salt of acrylic acid, a salt of methacrylic acid, a maleic acid salt, a maleic anhydride salt, an itaconic acid salt, a crotonic acid salt and combinations thereof, more preferably selected from acrylic acid, a salt of the acid acrylic acid, methacrylic acid, a salt of methacrylic acid and their combinations or

• the monomer (a2) is an ester Ci-C ₆ ester or a C _l -C ₄ alkyl or is a Ci-C ester in ₇ of the acrylic acid ester or a Ci-C ₇ acid methacrylic acid, preferably chosen from methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, ethylhexyl methacrylate, and their combinations, more preferably ethyl acrylate, butyl acrylate, methyl methacrylate and their combinations or

The monomer (a1) is chosen from acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, crotonic acid, a salt of acrylic acid, a salt of methacrylic acid, a maleic acid salt, a maleic anhydride salt, an itaconic acid salt, a crotonic acid salt and combinations thereof, most preferably acrylic acid or methacrylic acid; and the monomer (a2) is a C ₁ -C ₆ ester or a C ₁ -C ₄ ester or is a C ₁ -C ₇ ester of acrylic acid or a C ₁ -C ₇ ester of methacrylic acid , preferably chosen from methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, ethylhexyl methacrylate and the like. combinations, more preferably ethyl acrylate, butyl acrylate, methyl methacrylate and combinations thereof or

The polymerization reaction uses:

20 to 70 mol% or 30 to 60 mol%, preferably 30 to 55 mol% or 30 to 50 mol%, of monomer (a1) and

relative to the total molar amount of monomers (a1) and (a2).

7. Composition according to one of claims 1 to 6 wherein the hydrophilic phase comprises from 0.4 to 10% by weight, from 0.4 to 9% by weight or from 0.4 to 8% by weight, preferably from 0.5 to 10% by weight, from 0.5 to 9% by weight or from 0.5 to 8% by weight or from 0.6 to 10% by weight, from 0.6 to 9% by weight or from 0.6 to 8% by weight of polymer (P) relative to the amount of hydrophilic phase.

8. Composition according to one of claims 1 to 7 for which the polymer (P) is prepared by a polymerization reaction also implementing:

(a3) at least one compound selected from 2-acrylamido-2-methylpropanesulphonic acid, ethoxymethacrylate sulfonic acid, sodium methallylsulfonate, styrene sulfonate hydroxyethylacrylate phosphated, hydroxypropylphosphate phosphated, hydroxyethylhexylphosphate acrylate, hydroxyethyl phosphated methacrylate, phosphated hydroxypropyl methacrylate, phosphatized hydroxyethylhexyl methacrylate, their salts and combinations, preferably less than 20 mol%, preferably from 0.2 to 20 mol%, in particular from 0.5 to 10 mol%, monomer (a3) relative to the total molar amount of monomers or

(a4) at least one compound selected from hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethylhexyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxyethylhexyl methacrylate, preferably less than 20 mol%, preferably 0.2 to 20%. molar, in particular from 0.5 to 10 mol%, of monomer (a4) relative to the total molar amount of monomers or (a5) at least one crosslinking monomer or at least one monomer comprising at least two olefinic unsaturations, preferably less than 5 mol%, preferably from 0.01 to 4 mol%, in particular from 0.02 to 4 mol% or from 0.02 to 2 mol%, in particular from 0.02 to 1 mol%, of monomer ( a5) relative to the total molar amount of monomers.

9. Composition according to one of claims 1 to 8 for which:

The polymer (P) is totally or partially neutralized, preferably by means of at least one compound selected from among NaOH, KOH, ammonium derivatives, ammonia, and aminated bases, for example triethanolamine, aminomethylpropanol or 2-amino-2-methyl- propanol (AMP) and their combinations or The polymer (P) is totally or partially coacervated, preferably:

by reducing the pH of the dispersion (D), for example by reducing the pH to a value of less than 6.5, in particular by means of an acidic compound, in particular by means of at least one organic acid or mineral compound , in particular an acidic compound selected from phosphoric acid, citric acid, glucono-lactone, lactic acid, salicylic acid, glycolic acid, ascorbic acid, glutamic acid, hydrochloric acid, acetic acid, D-gluconic acid, sulphonic acid, methanesulfonic acid , benzimidazolesulfonic acid, tartaric acid, 4-aminobenzoic acid, benzoic acid, sorbic acid, phenylbenzimidazole sulfonic acid, benzylidene camphor sulfonic acid, terephthalylidene dicamphor sulfonic acid or

10. Composition according to one of claims 1 to 9 also comprising inorganic particles (for example titanium dioxide particles, iron oxide particles, zinc oxide particles), coated mineral particles, including coated with a hydrophobic compound, for example stearic acid (for example titanium dioxide particles coated with a hydrophobic compound, for example stearic acid), an organic sunscreen (for example avobenzone, ethylhexyltriazone, benzophenone-3, octocrylene, benzophenone-2, benzophenone-4, ethylhexylsalicylate, 4-methylbenzylidene camphor, octyl-N, N-dimethyl PABA, ethylhexyl dimethyl PABA, ethylhexyl methoxycinnamate, isoamyl methoxycinnamate, butyl methoxydibenzoylmethane, diethylamino hydroxybenzoyl hexyl benzoate, bis-ethylhexyloxyphenol methoxyphenyl triazine, drometrizole trisiloxane, methylene bis-benzotriazolyl tetramethylbutylphenol, diethylhexylbutamido triazone, ethyl exyl triazone, isoamyl p-methoxycinnamate, polysilicon-15, tris biphenyl triazine, homomenthyl salicylate, PEG-25 PABA), lipophilic cosmetic active molecules, water-soluble cosmetic active molecules.

11. Formulation chosen from a sun protection formulation, a makeup formulation, a skin care formulation and a hair care formulation, comprising at least one cosmetic composition according to one of claims 1 to 10.

A method of preparing a cosmetic composition in the form of a water-resistant emulsion, free of film-forming agent and surfactant compound, and comprising:

The preparation of a hydrophilic continuous phase comprising:

at least one hydrophilic compound having a pH greater than or equal to 6.5 and at least one emulsifying polymer (P) prepared by at least one polymerization reaction:

13. The method of preparation according to claim 12:

For which the addition is carried out at a temperature ranging from 10 to 90 ° C. or from 15 to 75 ° C. or at ambient temperature or else

Also comprising adjusting the final pH of the composition, preferably adjusting to a pH ranging from 4 to 13 or from 4 to 12 or from 4 to 11, more preferably to a pH ranging from 5 to 13 or 5; at 12 or 5 to 11, more preferably at a pH of 6 to 13 or 6 to 12 or 6 to 11.

14. Method of preparation according to one of claims 12 or 13 for which the cosmetic composition is defined according to one of claims 1 to 10.

15. A method for improving the water resistance of a cosmetic composition in the form of an emulsion, free from film-forming agent and surfactant compound, comprising adding to the cosmetic composition at least an emulsifying polymer (P) prepared by at least one polymerization reaction:

(a2) at least one ester Ci-C ₇ of a compound derived from an acid selected from acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid G and G tonic acid.

16. Cosmetic treatment method using a composition according to one of claims 1 to 10 or by means of a formulation according to claim 11 or by means of a composition prepared according to the method according to one of the claims. 12 to 14, comprising the application, in particular the application on the skin, of this composition or this formulation.