Cosmetic composition comprising a gelling agent and specific particles for optical performance in masking imperfections

Abstract

Cosmetic composition comprising a gelling agent and specific particles for optical performance in masking imperfections. The present invention relates to a composition comprising, in a physiologically acceptable medium: - at least one gelling agent selected from homo- and copolymers comprising a monomer of 2-acrylamido-2-methylpropanesulfonic acid, clays, polysaccharides consisting solely of glucose, fucose-rich polysaccharides, and mixtures thereof; and - at least one particle having a size D[50] between 100 nm and 5 µm and a refractive index greater than 1.6. The present invention also relates to a cosmetic process for the care of keratinous materials, preferably the skin, comprising the application to said keratinous materials of a composition according to the invention. Figure for the abstract: none

Description

Title of the invention: Cosmetic composition comprising a gelling agent and specific particles for optical performance in masking imperfections

[0001] The present invention relates to a composition comprising, in a physiologically acceptable medium:

[0002] - at least one gelling agent selected from homo- and copolymers comprising a 2-acrylamido-2-methylpropanesulfonic acid monomer, clays, polysaccharides consisting solely of glucose, fucose-rich polysaccharides and mixtures thereof; and

[0003] - at least one particle having a size D

[50] between 100 nm and 5 pm and having a refractive index greater than 1.6.

[0004] The present invention also relates to a cosmetic process for the care of keratinous materials, preferably the skin, comprising the application to said keratinous materials of a composition according to the invention.

[0005] The cosmetic compositions for skincare or complexion makeup referred to are generally intended to even out the complexion. In particular, they aim to conceal and / or blur imperfections. This blurring effect, which camouflages the skin's micro-relief, is also called the soft-focus effect.

[0006] In cosmetics, the search for soft-focus properties to mask imperfections is a real challenge.

[0007] To add blurring effects and obtain a soft-focus effect, it is classically known to use particles having a size D

[50] greater than 5 pm, such as spheres of silica or cellulose for example.

[0008] However, such particles can cause problems with comfort and sensory perception during application. Indeed, these particles are generally added in a significant quantity, which leads to these cosmetic drawbacks.

[0009] To overcome this discomfort, smaller particles can be used. However, the use of gelling agents conventionally used in cosmetics, such as xanthan gum, (meth)acrylic polymer (of the Pemulen type) or cellulose derivatives (such as hydroxyethylcellulose or cellulose gum), does not allow for the proper dispersion of these particles, resulting in poor cosmetic and optical performance.

[0010] There is therefore a need for compositions exhibiting a soft-focus effect, containing optimal particle dispersion. Such dispersion then allows for the full expression of the optical properties of the particles and thus the blurring of imper- conditions such as wrinkles, fine lines and / or pores.

[0011] The present invention solves this problem.

[0012] Indeed, the Applicant has now discovered that the dispersion of particles of size D

[50] between 100 nm and 5 pm and having a specific refractive index provides the cosmetic film with soft-focus effects. Moreover, thanks to the addition of a particular gelling agent, no particle aggregation is observed: the dispersion is optimal.

[0013] The combination of particles and gelling agent according to the invention thus allows optimal dispersion of particles, while improving their soft-focus effect capacity (including masking and coverage).

[0014] The present invention therefore relates to a composition comprising, in a physiologically acceptable medium:

[0015] - at least one gelling agent selected from homo- and copolymers comprising a 2-acrylamido-2-methylpropanesulfonic acid monomer, clays, polysaccharides consisting solely of glucose, fucose-rich polysaccharides and mixtures thereof; and

[0016] - at least one particle having a size D

[50] between 100 nm and 5 pm and having a refractive index greater than 1.6.

[0017] The composition is preferably in the form of an emulsion, more preferably direct (oil-in-water).

[0018] By “physiologically acceptable”, we mean a medium compatible with keratinous materials.

[0019] The present invention also relates to a cosmetic process for the care of keratinous materials, preferably the skin, comprising the application to said keratinous materials of a composition according to the invention. Gelling agent

[0020] The composition according to the invention comprises at least one gelling agent selected from homo- and copolymers comprising a monomer of 2-acrylamido-2-methylpropane sulfonic acid, clays, polysaccharides consisting solely of glucose and fucose-rich polysaccharides.

[0021] The gelling agent ensures good dispersion of the particles and thus allows the expression of their optical properties, without cosmetic inconvenience.

[0022] The concentration of gelling agent (i.e. active matter) generally ranges from 0.1 to 20% by weight relative to the total weight of the composition, and preferably from 0.5 to 15% by weight, preferably from 0.5 to 10% by weight and even more particularly from 0.5 to 5% by weight.

[0023] Polymers comprising a monomer of 2-acrylamido-2-methylpropane sulfonic

[0024] The gelling agent can be chosen from homo- and copolymers comprising a 2-acrylamido-2-methylpropane sulfonic acid monomer.

[0025] Homopolymers of 2-acrylamido-2-methylpropane sulfonic acid (AMPS®, Lubrizol monomer) or their salts may be crosslinked or not.

[0026] Such a homopolymer can have a number average molecular weight ranging from 1000 to 20,000,000 g / mol, preferably ranging from 20,000 to 5,000,000 and even more preferably from 100,000 to 1,500,000 g / mol.

[0027] More specifically, 2-acrylamido-2-methylpropane-sulfonic acid and its partially or totally neutralized forms are used.

[0028] When polymers are crosslinked, the crosslinking agents can be chosen from among the olefinic polyunsaturated compounds commonly used for crosslinking polymers obtained by radical polymerization.Examples of crosslinking agents include divinylbenzene, diallyl ether, dipropylene glycol diallylether, polyglycol diallylethers, triethylene glycol divinylether, hydroquinone diallyl ether, di(meth)acrylate of ethylene glycol or tetraethylene glycol, trimethylol propane triacrylate, methylene bisacrylamide, methylene bismethacrylamide, triallylamine, triallylcyanurate, diallylmaleate, tetraallylethylenediamine, tetraallyloxyethane, trimethylolpropane diallylether, allyl (meth)acrylate, allylic ethers of sugar alcohols, or other allyl- or vinyl ethers of polyfunctional alcohols, as well as allylic esters of acid derivatives. phosphoric and / or vinylphosphonic compounds, or mixtures of these compounds.

[0029] According to a preferred embodiment of the invention, the crosslinking agent is selected from methylene-bis-acrylamide, allyl methacrylate, or trimethylol propane triacrylate (TMPTA). The degree of crosslinking generally ranges from 0.01 to 10% by mol and more particularly from 0.2 to 2% by mol relative to the polymer.

[0030] The homopolymer comprises only monomers with a sulfonic group and, if it is crosslinked, one or more crosslinking agents.

[0031] Preferred 2-acrylamido-2-methylpropanesulfonic acid homopolymers are generally characterized by the fact that they comprise, randomly distributed:

[0032] a) 90 to 99.9% by weight of motifs of the following general formula:

[0033] [Chem.l] CH. ----CH^SCÇX* CHA

[0034] in which X+ designates a proton, an alkali metal cation, an alkaline earth cation or the ammonium ion, at most 10 mol% of the X+ cations being H+ protons;

[0035] and crosslinking motifs from at least one monomer having at least two olefinic double bonds, the weight proportions being defined in relation to the total weight of the polymer.

[0036] The homopolymers according to the invention most particularly preferred comprise 98 to 99.5% by weight of motifs of formula (I) above and 0.2 to 2% by weight of crosslinking motifs.

[0037] Examples of polymers of this type include the crosslinked and neutralized homopolymer of 2-acrylamido 2-methylpropane sulfonic acid, marketed by Clariant under the trade name "Hospacerin AMPS®" (INCI name: Ammonium Polyacryldimethyltauramide).

[0038] The polymer may also be an amphiphilic homopolymer (or hydrophobic modified homopolymer) selected from statistical amphiphilic polymers of 2-acrylamido-2-methylpropanesulfonic acid modified by reaction with an n-monoalkylamine or a di-n-alkylamine at C6-C22, such as those described in document WO-A-00 / 31154, which are grafted homopolymers.

[0039] The gelling agent may also be selected from copolymers of acrylamido-2-methylpropanesulfonic acid or its salts and one or more non-ionic monomers. They may be cross-linked or non-cross-linked.

[0040] When polymers are crosslinked, the crosslinking agents can be chosen from among the olefinic polyunsaturates commonly used for crosslinking polymers obtained by radical polymerization. Such agents are described above.

[0041] According to a preferred embodiment of the invention, the crosslinking agent is selected from methylene-bis-acrylamide, allyl methacrylate, or trimethylol propane triacrylate (TMPTA). The degree of crosslinking generally ranges from 0.01 to 10% by mol and more particularly from 0.2 to 2% by mol relative to the polymer.

[0042] The copolymers according to the invention are obtained from AMPS® (Lubrizol monomer) and one or more hydrophilic or hydrophobic non-ionic monomers with ethylenic unsaturation and, if they are crosslinked, one or more crosslinking agents such as those defined above.

[0043] The 2-acrylamido-2-methylpropane sulfonic acid monomer of the copolymer contained in the composition according to the invention is in free form or is partially or totally neutralized by a mineral base (sodium hydroxide, potassium hydroxide, ammonia) or an organic base such as mono-, di-, or tri-ethanolamine, an ami-nomethylpropanediol, N-methylglucamine, basic amino acids such as arginine and lysine, as well as mixtures of these compounds.

[0044] Preferably, the 2-acrylamido-2-methylpropane sulfonic acid monomer is partially or totally salted as an ammonium or sodium salt.

[0045] Preferably, the 2-acrylamido-2-methylpropane sulfonic acid monomer is totally salted, preferably in the form of an ammonium or sodium salt.

[0046] The copolymers of AMPS® (Lubrizol monomer) contain one or more non-ionic monomers selected from water-soluble ethylenic unsaturation monomers, hydrophobic monomers, or mixtures thereof.

[0047] Examples of non-ionic water-soluble monomers include:

[0048] - (meth)acrylamide,

[0049] - N-vinylacetamide and N-methyl N-vinylacetamide,

[0050] - N-vinylformamide and N-methyl N-vinylformamide,

[0051] - maleic anhydride,

[0052] - vinylamine,

[0053] - N-vinyllactams comprising a cyclic alkyl group having from 4 to 9 atoms of carbon, such as N-vinylpyrrolidone, N-butyrolactam and N-vinylcaprolactam,

[0054] - vinyl alcohol of formula CH2=CHOH,

[0055] - water-soluble vinyl monomers of the following formula (2):

[0056] [Chem.2] <- * L. V"" (2)

[0057] in which:

[0058] - Rb is chosen from H, -CH3, -C2H5 or -C3H7

[0059] - X2 is chosen from alkyl oxides of the type -ORi6 where Ri6 is a hy radical drocarbon, linear or branched, saturated or unsaturated, having from 1 to 6 carbons, possibly- typically substituted by a halogen atom (iodine, bromine, chlorine, fluorine); a hydroxy group (-OH); ether.

[0060] Examples include glycidyl (meth)acrylate, hydroxyethyl (meth)acrylate, and ethylene glycol, diethylene glycol or polyalkylene glycol (meth)acrylates.

[0061] Preferably the water-soluble monomer is chosen from acrylamide, vinylpyrrolidone, hydroxyalkyl(meth)acrylates, more particularly vinylpyrrolidone.

[0062] Examples of copolymers of AMPS® (Lubrizol monomer) according to the invention with hydrophilic monomers include:

[0063] - copolymers of acrylamido-2-methylpropane sulfonic acid and vinylpyr rolidone, such as the commercial product ARISTOFLEX AVC sold by CLARIANT,

[0064] - crosslinked acrylamide / acrylamido-2-methyl propane sulfonate copolymers sodium, such as that used in the commercial product SEPIGEL 305® (INCI name: Polyacrylamide / Ci3-Ci4 Isoparaffin / Laureth-7) or that used in the commercial product sold under the name SIMULGEL 600® (INCI name: Acrylamide / Sodium Acryloyldimethyltaurate / Isohexadecane / Polysorbate-80) by the company SEPPIC;

[0065] - copolymers of AMPS® (Lubrizol monomer) and hydroxyethyl acrylate, such as the AMPS® sodium / hydroxyethyl acrylate copolymer such as that used in the commercial product sold under the name SIMULGEL NS® by the company SEPPIC (INCI name: Hydroxyethyl acrylate / Sodium Acryloyldimethyltaurate copolymer (and) Squalane (and) Polysorbate 60);

[0066] - hydrophobically modified AMPS® copolymers such as the copolymer known under the INCI name: AMMONIUM ACRYLOYLDIMETHYLTAURATE / STEARETH-25 METHACRYLATE CROSSPOLYMER sold under the trade name ARISTOFLEX HMS by the company CLARIANT. Clays

[0067] The composition may include at least one clay. Clays are products already well known in themselves, which are described for example in the work "Mineralogy of clays, S. Caillère, S. Hénin, M. Rautureau, 2nd edition 1982, Masson".

[0068] Clays are silicates containing a cation that can be selected from the cations of calcium, magnesium, aluminum, sodium, potassium, lithium and mixtures thereof.

[0069] Examples of such products include clays of the smectite family such as montmorillonites, hectorites, bentonites, beidellites, saponites, as well as those of the vermiculite family, stevensite or chlorites.

[0070] These clays can be of natural or synthetic origin. Preferably, one uses clays that are cosmetically compatible and acceptable with keratinous materials such as skin.

[0071] The clay is preferably chosen from among hydrophilic clays. These clays are clays that can be modified by chemical compounds making the clay capable of swelling in aqueous media.

[0072] The clay may be chosen from montmorillonite, bentonite, hectorite, attapulgite, sepiolite and mixtures thereof.

[0073] The clay is preferably a bentonite or a hectorite.

[0074] These clays can be modified with a chemical compound selected from quaternary amines, tertiary amines, amino acetates, imidazolines, amino soaps, fatty sulfates, alkyl aryl sulfonates, amine oxides, and mixtures thereof.

[0075] Polysaccharides consisting solely of glucose and polysaccharides rich in fucose

[0076] The composition may include at least one polysaccharide consisting solely of glucose and / or at least one polysaccharide rich in fucose.

[0077] Polysaccharides consisting solely of glucose

[0078] Polysaccharides consisting solely of glucose are preferably chosen from sclerotium gum and modified or unmodified starches.

[0079] Sclerotium gum (or scleroglucan) is a hydrophilic polymer of natural origin. It is a polymerized glucose, which can be obtained from a variety of Sclerotium-type fungi, in particular Sclerotium rolfsii. Sclerotium gum (also called scleroglucan gum) is a polysaccharide consisting solely of glucose units. Sclerotium gum is used as a thickening and gelling agent. A particularly suitable sclerotium gum is available from Alban Mueller International under the trade name Amigel or Amigel Granule.

[0080] Starches are D-glucose polysaccharides. They can be modified or unmodified.

[0081] Preferably, unmodified starches will be used.

[0082] Among unmodified starches, examples include unmodified corn starches (INCI name: ZEA MAYS STARCH) such as the products sold under the trade names Farmal CS®, in particular the commercial product Farmal CS 3650® by Corn Products International. Also examples include unmodified rice starches (INCI name: ORYZA SATIVA (RICE) STARCH) such as the commercial product REMY DR I® sold by BENEO-REMY.

[0083] One can also mention distarch phosphates or compounds rich in distarch phosphate, in particular hydroxypropyl phosphate ethers of distarch having the INCI name Hydroxypropyl Starch Phosphate such as the products sold under the trade names Farinex VA70 C or FARMAL MS 689® of the company AVEBE Stadex; or the products sold under the trade names Structure BTC®, Structure HVS®, Structure XL® or STRUCTURE ZEA® of NATIONAL STARCH (corn distarch phosphate).

[0084] Polysaccharides rich in fucose

[0085] Fucose-rich polysaccharides are preferably polyholosides comprising more than 10 sugars. In all cases, the fucose-rich polysaccharide comprises at least one fucose unit.

[0086] The sugars can be chosen from all conceivable sugars, of natural or synthetic origin, and in particular such as:

[0087] aldoses such as pentoses like ribose, arabinose, xylose or apiose, or hexoses such as glucose, fucose, mannose or galactose,

[0088] ketoses such as fructose,

[0089] deoxyses, such as rhamnose, digitoxosis, cymarosis or oleandrosis, or

[0090] sugar derivatives such as uronic acids like mannuronic acid, glu- curonic, galacturonic or glucuronic, or even itols such as mannitol or sorbitol.

[0091] Among these sugars, fucose will be used more preferentially, and possibly trehalose and / or hexoses, and more particularly glucose, mannose and / or galactose.

[0092] Their derivatives, in particular alkylated ones, such as methylated derivatives like methylglucose, as well as compounds containing one or more sugars, and mixtures thereof, can also be mentioned.

[0093] Preferably, the fucose-rich polysaccharide is a polymer containing fucose, galactose and galacturonic acid.

[0094] Examples of fucose-rich polysaccharides include natural compounds such as honey, and polymers such as the product marketed under the name "Fucogel 1000" by the company Solabia (name CTFA Biosaccharide gum-1), a polymer containing fucose, galactose and galacturonic acid. Particles

[0095] The composition according to the invention comprises at least one particle having a size D

[50] between 100 nm and 5 pm and having a refractive index greater than 1.6.

[0096] Preferably, the particles have a size D

[50] between 100 nm and 2 pm, preferably between 200 nm and 1 pm, preferably between 200 nm and 800 nm.

[0097] The particle size is that given by the statistical distribution at half the population, referred to as D

[50] . According to the invention, D

[50] is therefore expressed as the number of particles. Particle size is measured by laser diffraction particle size analysis. Particle size measurements are performed on a Malvem 3000 particle size analyzer (laser diffraction) equipped with a 3000G hydro-crosslinking tank.

[0098] The Mastersizer uses laser diffraction to measure particle size. This technique involves measuring the intensity of the light scattered when a laser beam passes through a sample of dispersed particles. This data is then analyzed to calculate the particle size.

[0099] The particle refractive index CS( calculated from the composition of the materials in volume proportion, defined by the following equation with ni the index of material i and the volume fraction of material i in the particle:

[0100] [Math.l] = JP

[0101] The particle has a refractive index greater than 1.6. Preferably, the particle has a refractive index between 1.7 and 2.8, preferably between 1.7 and 2.

[0102] The particles may have a spherical or non-spherical shape. When the particles have a non-spherical shape, they may in particular be in the form of platelets.

[0103] Preferably, the particles are mineral particles. Preferably, the particles are boron nitride particles.

[0104] Preferably, the particles are white in color.

[0105] Examples of usable particles according to the invention include:

[0106] - boron nitride particles marketed by Saint Gobain under the name SP1. They have a size D

[50] of 1.2 pm and a refractive index of 1.74; or

[0107] - the particles marketed under the name Boron Nitride Powder Très BN PUHP 3002 by Saint Gobain Ceramics. These particles are boron nitride platelets / flakes. They have a refractive index of 1.74 and a D

[50] size of 2 pm.

[0108] Preferably, the composition according to the invention comprises from 0.1 to 20% by weight of particles relative to the total weight of the composition, and preferably from 0.2 to 10% by weight, preferably from 0.3 to 7% by weight and even more particularly from 0.4 to 3% by weight. Aqueous phase

[0109] The composition according to the invention may include an aqueous phase.

[0110] The aqueous phase comprises water and optionally a water-soluble organic solvent at 25°C, chosen for example from polyols; linear or branched C2-C4 alkanols such as ethanol and isopropanol, propanol, butanol; and their mixtures.

[0111] A polyol is defined as a hydrocarbon chain comprising at least 2 carbon atoms, preferably from 2 to 50 carbon atoms, preferably from 4 to 20 carbon atoms, preferably from 2 to 10 carbon atoms, and preferably from 2 to 6 carbon atoms, and bearing at least two hydroxyl groups. The polyols used in the present invention may have a weight-average molecular mass less than or equal to 1000, preferably between 90 and 500. The polyol may be natural or synthetic. The polyol may have a linear, branched, or cyclic molecular structure.

[0112] The polyol may be selected from glycerin and its derivatives, and from glycols and their derivatives. The polyol may be selected from the group consisting of glycerin, diglycerin, polyglycerin, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, pentylene glycol, hexylene glycol, 1,3-propanediol, 1,5-pentanediol, octane 1,2-diol, polyethylene glycols, in particular having 5 to 50 ethylene oxide groups, and sugars such as sorbitol, and mixtures thereof. Preferably, the polyol is glycerin.

[0113] Said water-soluble organic solvent(s) may be present in a content ranging from 1% to 30% by weight, relative to the total weight of the composition, preferably ranging from 2% to 25% by weight, and preferably ranging from 5% to 20% by weight.

[0114] The composition generally comprises from 10% to 99% by weight of water relative to the total weight of the composition, preferably from 30% to 98% by weight, preferably from 35% to 90% by weight.

[0115] Preferably, the composition according to the invention further comprises an oily phase.

[0116] Preferably, the composition according to the invention is an oil-in-water emulsion. Oily phase

[0117] The composition according to the invention preferably also comprises at least one oily phase. When the composition used according to the invention comprises an oily phase, this phase preferably contains at least one oil, in particular a cosmetic oil. It may also contain other fatty substances.

[0118] By "oil" is meant a non-aqueous compound, liquid at 25°C and atmospheric pressure (1.013.105 Pa), immiscible with water.

[0119] By "immiscible" is meant that the mixture of the same quantity of water and oil, after stirring, does not lead to a stable solution comprising only one phase, under the aforementioned temperature and pressure conditions. The observation is made visually or, if necessary, using a phase-contrast microscope, on 100 g of the mixture obtained after sufficient Rayneri shaking to produce a vortex. within the mixture (for guidance 200 to 1000 rpm); the resulting mixture being left to rest, in a closed bottle, for 24 hours at room temperature before observation.

[0120] Examples of oils that can be used in the composition of the invention include:

[0121] - hydrocarbon oils of animal origin, such as perhydrosqualene;

[0122] - vegetable hydrocarbon oils, such as liquid triglycerides fatty acids containing 4 to 10 carbon atoms such as the triglycerides of heptanoic or octanoic acids or, for example, sunflower, corn, soybean, pumpkin, grapeseed, sesame, hazelnut, apricot, macadamia, arara, sunflower, castor, avocado oils, the triglycerides of caprylic / capric acids such as those sold by the company Stearineries Dubois or those sold under the names Miglyol 810, 812 and 818 by the company Dynamit Nobel, jojoba oil, shea butter oil;

[0123] - synthetic esters and ethers, particularly of fatty acids, such as oils of formulas R1COOR2 and R1OR2 in which RI represents the remainder of a fatty acid comprising 8 to 29 carbon atoms, and R2 represents a hydrocarbon chain, branched or unbranched, containing 3 to 30 carbon atoms, such as Purcellin oil, isononyl isononanoate, isopropyl myristate, ethyl-2-hexyl palmitate, octyl-2-dodecyl stearate, octyl-2-dodecyl erucate, isostearyl isostearate; hydroxylated esters such as isostearyl lactate, octylhydroxystearate, octyldodecyl hydroxystearate, diisostearylmalate, triisocetyl citrate, heptanoates, octanoates, decanoates of fatty alcohols; polyol esters, such as propylene glycol dioctanoate, neopentylglycol diheptanoate and diethylene glycol diisononanoate; and pentaerythritol esters such as pentaerythrityl tetraisostearate or dipentaerythrityl pentaisononanoate;

[0124] - linear or branched hydrocarbons, of mineral or synthetic origin, such as paraffin oils, volatile or not, and their derivatives, branched chain hydrocarbon oils containing 10 to 20 carbon atoms such as isohexadecane, isododecane, isoparaffins and their mixtures, petroleum jelly, polydecenes, polyisobutenes, hydrogenated polyisobutenes such as, for example, Parleam® marketed by NIPPON OIL FATS, PANALANE H-300 E marketed by AMOCO, VISEAL 20000 marketed by SYNTEAL, REWOPAL PIB 1000 marketed by WITCO, or PARLEAM LITE marketed by NOF Corporation;

[0125] - partially hydrocarbon and / or silicone fluorinated oils such as those described in document JP-A-2-295912;

[0126] - silicone oils such as volatile or non-volatile polymethylsiloxanes (PDMS) linear or cyclic silicone chains, liquid or paste-like at room temperature, including cyclopolydimethylsiloxanes (cyclomethicones) such as cyclohexasiloxane; polydimethylsiloxanes containing alkyl, alkoxy, or phenyl groups, pendant or at the end of the silicone chain, groups having from 2 to 24 carbon atoms; phenyl silicones such as phenyltrimethicones, phenyldimethicones, phenyltrimethylsiloxydiphenylsiloxanes, diphenyldimethicones, diphenylmethyldiphenyl trisiloxanes, 2-phenylethyltrimethylsiloxysilicates, and polymethylphenylsiloxanes; or

[0127] - their mixtures.

[0128] As indicated above, the composition according to the invention may include, in the oily phase, other fatty substances. Preferably, these fatty substances are chosen from fatty alcohols having 8 to 26 carbon atoms, such as cetyl alcohol, stearyl alcohol, the mixture of cetyl alcohol and stearyl alcohol (cetyl-stearyl alcohol), octyldodecanol, 2-butyloctanol, 2-hexyldecanol, 2-undecylpentadecanol, oleic alcohol or linoleic alcohol.

[0129] The quantity of oil phase can range for example from 0.1 to 40% by weight, preferably from 0.5 to 35% by weight, preferably from 1% to 30% by weight relative to the total weight of composition.

[0130] The composition of the invention may also contain adjuvants commonly used in the cosmetic and / or dermatological fields, such as active ingredients, preservatives, antioxidants, complexing agents, pH adjusters (acids or bases), perfumes, odor absorbers or coloring materials (pigments and dyes).

[0131] The quantities of these various adjuvants are those conventionally used in the field concerned, and for example from 0.01 to 20% of the total weight of the composition. These adjuvants, depending on their nature, can be introduced into the oil phase and / or into the aqueous phase.

[0132] The present invention also relates to a cosmetic process for the care of keratinous materials, preferably the skin, comprising the application to said keratinous materials of a composition according to the invention.

[0133] The following examples of compositions according to the invention are given by way of illustration and without limitation.

[0134] The quantities are given therein as % by weight of the total weight of composition (% w / w), unless otherwise stated.

[0135] Examples: preparation and evaluation of compositions METHODS Optical microscopy

[0136] Microscopic observations were carried out at 25°C between a slide and coverslip, using a Leica Zeiss microscope which operates in transmission mode (light passes through the sample), or by reflection if the object is opaque. Haze measurement

[0137] The Haze-Gard® (BYK Gardner) quantifies the perception of visual effects with objective measurements. It measures the intensity of light passing through a sample, which corresponds to the hemispheric (or total) transmittance. The higher a material's transmittance, the more transparent it is.

[0138] The Haze-Gard® separately measures Direct Transmittance (i.e., in the same direction as the incident ray) or Hemispherical Transmittance (in all directions of space, which is equivalent to total transmittance). The more hemispherical a material's transmittance is compared to its direct transmittance, the greater its "blurring" effect.

[0139] The Haze value (%) is defined to highlight this relationship between hemispheric transmittance and direct transmittance. Thus, the higher a material's Haze value, the greater its "soft focus" effect.

[0140] [Math.2] * (TH -JWH

[0141] The product is deposited in a controlled thickness of 25 µm using an automatic spreader (Byko drive®) onto a 50 µm transparent plastic film. After a drying time of 1 hour at room temperature and in open air, the optical parameters (T, H) are measured using the Haze-Gard at three separate points on the deposit to obtain an average. The condition of the film is also characterized. For the measurements to be meaningful, the deposit must be uniform, without streaks or heterogeneity. Opacity Measurement

[0142] The contrast ratio represents a measure of the covering power of the formula. To do this, a deposit is made on a glossy BYC contrast card (reference 2814 or 2830).

[0143] Once these deposits have been made, the tristimulus parameters XYZ and L*a*b* are measured on the white and black areas using the Minolta spectrometer.

[0144] From these parameters, we can then determine the contrast ratio (CR), which is defined as:

[0145] [Math.3] CR = * 100

[0146] with YFN, the average Y value measured on the black background, and YFB, the average Y value measured on the white background. The higher this value, the more the product will tend to provide colonic coverage. Preparation of compositions

[0147] The compositions are prepared by mixing the ingredients mentioned in water. RESULTS (in vitro) Evaluation of dispersion

[0148] Initially a macroscopic evaluation of the dispersion is carried out, after mixing the particles the homogeneity of the bulk and the deposit is observed and the different formulas are noted according to their appearance.

[0149] The protocol used is as follows: the overall appearance of approximately 5 mL of the formula is assessed (presence of inhomogeneity, grain, aggregates), then a gram of the formula is taken and spread on the black area of ​​a BYK contrast card using a glass slide. The presence or absence of poorly dispersed aggregates / grains of particles in the deposit is then observed. Indeed, good or poor dispersion can be observed.

[0150] Polymers not part of the invention are marked with a star. Optical characterization

[0151] These same compositions are characterized for their optical properties.

[0152] During the characterization of the optical properties of the different formulas presented above, it is observed that those containing the polymers of the invention allow for better optical performance (Haze & CR).

[0153] The results of all the tests are summarized below:

[0154] Reference and comparative compositions (all not part of the invention) Gel Only Gel Only Gel Only Gel Only Counter-example Counter-example Glycerin 10 10 10 10 10 10 Silica - - - - 1 1 Hectorite 5 - - - 5 - Pemulen* - 0.85 - - - - Sepigel - - 2 - - 2 Xanthan* - - - 1.5 - - Gel Appearance Soft Gel Soft Gel Soft Gel Soft Gel Good Dispersion Good Dispersion Haze 23.3 1.86 10 1.74 13.5 15.8 Contrast Ratio 3.34 1.06 1.78 1.06 1.92 2.45 Interest Reference Reference Reference Reference Non-invention Particle Non-invention Particle

[0156] Silica = RICESILK silica particles from Soliance, which are comparative and have a refractive index of 1.47 and a size D

[50] of 10 pm

[0157] Hectorite = marketed under the name Bentone Hydroclay™ 2000 LO by Elementis

[0158] Pemulen (not part of the invention) = INCI name: ACRYLATES / C10-30 ALKYL ACRYLATE CROSSPOLYMER from Lubrizol

[0159] Sepigel = name INCI : POLYACRYLAMIDE (and) C13-14 ISOPARAFFIN (and) LAURETH-7 from SEPPIC

[0160] Xanthane (hors invention) = xanthan gum from CP KELCO (trade name KELTROL CG). Example 1 Example 2 Example 3 Example 4 Example 5 Counter-example Counter-example Counter-example Counter-example Glycerol and 10 10 10 10 Boron Nitride 2 - - - 0.5 0.5 0.5 - - 0.5 Bentonite 2 - - - - Xanthan e* - - - - - 0.84 - 0.84 - Aspect Good Good Good Good Good Bad Bad Bad Bad Bad of the gel eeeeeeeee dispersed7 dispersed dispersed dispersed dispersed dispersed dispersed 55 36.5 53.4 29 10.5 28 17 1.19 Contrast Ratio 9.61 6.42 3.14 6.06 3.82 1.44 2.81 1.97 1.25 OK

[0162] KO = noun OK

[0163] Boron nitride 1 = boron nitride particles according to the invention at 0.5% (w / w) (Boron Nitride Powder Very BN PUHP 3002 from Saint Gobain Ceramics)

[0164] Boron nitride 2 = boron nitride particles according to the invention marketed by Saint Gobain under the name SP1

[0165] Bentonite = marketed by Kunimine

[0166] Hectorite = marketed under the name Bentone Hydroclay™ 2000 LO by Elementis

[0167] Pemulen (excluding invention) = INCI name: ACRYLATES / C10-30 ALKYL ACRYLATE CROSSPOLYMER from Lubrizol

[0168] Sepigel = INCI name: POLYACRYLAMIDE (and) C13-14 ISOPARAFFIN (and) LAURETH-7 from SEPPIC

[0169] Xanthan (not part of the invention) = CP KELCO xanthan gum (trade name KELTROL CG).

[0170] With particles according to the invention, different states of aggregation can be observed: in the case of small, well-dispersed particles, a significant increase in opacity (Contrast Ratio SCE > 3) and haze potential is noted. Indeed, a significant performance difference is observed between the control bases (not part of the invention) and the bases with well-dispersed particles (invention).

[0171] It is also observed that, in the case of poor dispersion, the optical properties are not expressed at their full potential: this is the case of the xanthan-glycerin gel containing boron nitride particles Boron Nitride Powder Très BN PUHP 3002 from Saint Gobain Ceramics: CR SCE of 1.97 and Haze of 17. In addition, the inventors have shown that the use of larger caliber particles (silica particles) does not present a dispersion problem, but does not fulfill the specifications of the invention (i.e. in terms of refractive index and size): the properties in terms of opacity are not as efficient (CR ~ 1-2.45, table 1). Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Glycerin 10 10 10 10 10 10 10 Boron Nitride 1 0.5 0.5 0.5 - - 0.5 0.5 Boron Nitride 2 - - - 0.5 0.5 - - Bentonite 5 - - - - - - Hectorite - 5 - 5 - - - Biosaccharide - - - - - - 1.5 Sepigel - - 2 - 2 - - Starch - - - - - 4.5 - Gel Appearance Good Dispersion Good Dispersion Good Dispersion Good Dispersion Good Dispersion Good Dispersion Interest OK OK OK OK OK KO KO Counter-example Counter-example Counter-example Counter-example Counter-example Glycerin 10 10 10 10 10 Boron Nitride 1 0.5 0.5 0.5 0.5 Boron Nitride 2 0.5 HEC* 2 Pemulen* 0.85 0.85 Aquasorb* 0.5 Xanthan* 1.5 Gel appearance Poor dispersion Presence of aggregates Poor dispersion Presence of aggregates Poor dispersion Presence of aggregates Poor dispersion Presence of aggregates Poor dispersion Presence of aggregates Interest Polymer not subject to invention Polymer not subject to invention Polymer not subject to invention Polymer not subject to invention Polymer not subject to invention

[0174] Boron nitride 1 = 0.5% (w / w) boron nitride particles (Boron Nitride Powder Très BN PUHP 3002 from Saint Gobain Ceramics)

[0175] Boron nitride 2 = boron nitride particles marketed by Saint Gobain under the name SP1

[0176] Starch = INCI name: HYDROXYPROPYL STARCH PHOSPHATE from Cargill (88% by weight hydroxypropyl starch phosphate and 12% by weight water)

[0177] Sepigel = INCI name: POLYACRYLAMIDE (and) C13-14 ISOPARAFFIN (and) LAURETH-7 from SEPPIC

[0178] Pemulen (excluding invention) = INCI name: ACRYLATES / C10-30 ALKYL ACRYLATE CROSSPOLYMER from Lubrizol

[0179] Hectorite = marketed under the name Bentone Hydroclay™ 2000 LO by Elementis

[0180] Bentonite = marketed by Kunimine

[0181] Biosaccharide = Fucogel 1000 from Solabia (CTFA name Biosaccharide gum-1)

[0182] HEC (excluding invention) = hydroxyethylcellulose

[0183] Aquasorb A500 (not part of the invention) = Ashland cellulose gum

[0184] Xanthan (not part of the invention) = CP KELCO xanthan gum (trade name KELTROL CG).

[0185] It appears from these results that only compositions comprising a gelling agent chosen from among homo- and copolymers comprising a monomer of 2-acrylamido-2-methylpropane sulfonic acid, clays, polysaccharides consisting solely of glucose and polysaccharides rich in fucose, and particles having a size D

[50] between 100 nm and 5 pm and having a refractive index greater than 1.6, exhibit both good dispersion and the desired optical properties.

Claims

Claims

1. Composition comprising, in a physiologically acceptable medium - at least one gelling agent chosen from homo- and copolymers comprising a 2-acrylamido-2-methyl-propanesulfonic acid monomer, clays, polysaccharides consisting solely of glucose, polysaccharides rich in fucose and mixtures thereof; and - at least one particle having a size D[50] of between 100 nm and 5 pm and having a refractive index greater than 1.

6.

2. Composition according to claim 1, characterized in that it comprises a concentration of gelling agent in active material ranging from 0.1 to 20% by weight relative to the total weight of the composition, and preferably from 0.5 to 15% by weight, preferably from 0.5 to 10% by weight and even more particularly from 0.5 to 5% by weight.

3. Composition according to claim 1 or 2, characterized in that the homo- or copolymer comprising a 2-acrylamido-2-methylpropanesulfonic acid monomer is chosen from crosslinked and neutralized homopolymers of 2-acrylamido-2-methylpropanesulfonic acid and copolymers of acrylamido-2-methylpropanesulfonic acid or its salts and one or more non-ionic, crosslinked or non-crosslinked monomers, preferably chosen from crosslinked and neutralized homopolymers of 2-acrylamido-2-methylpropanesulfonic acid, copolymers of acrylamido-2-methylpropanesulfonic acid and vinylpyrrolidone, crosslinked acrylamide / sodium acrylamido-2-methylpropanesulfonate copolymers, copolymers of acrylamido-2-methylpropanesulfonic acid and hydroxyethyl acrylate and hydrophobically modified acrylamido-2-methyl propane sulfonic acid copolymers.

4. Composition according to claim 1 or 2, characterized in that the clay is chosen from montmorillonites, hectorites, bentonites, beidellites, saponites and their mixtures, preferably it is chosen from montmorillonite, bentonite, hectorite, attapulgite, sepiolite and their mixtures, preferably it is a bentonite or a hectorite.

5. Composition according to claim 1 or 2, characterized in that the polysaccharide consisting solely of glucose is chosen from sclerotium gum and modified or unmodified starches; preferably selected from sclerotium gum and unmodified starches such as unmodified corn starches, unmodified rice starches or hydroxypropyl ethers of distarch phosphate.

6. Composition according to claim 1 or 2, characterized in that the fucose-rich polysaccharide is a polymer containing fucose, galactose and galacturonic acid.

7. Composition according to one of the preceding claims, characterized in that the particle has a size D[50] of between 100 nm and 2 pm, preferably of between 200 nm and 1 pm, preferably of between 200 nm and 800 nm.

8. Composition according to one of the preceding claims, characterized in that the particle has a refractive index of between 1.7 and 2.8; preferably, the particle has a refractive index of between 1.7 and 2.

9. Composition according to one of the preceding claims, characterized in that the particle is chosen from boron nitride particles.

10. Composition according to one of the preceding claims, characterized in that it comprises from 0.1 to 20% by weight of particles relative to the total weight of the composition, and preferably from 0.2 to 10% by weight, preferably from 0.3 to 7% by weight and even more particularly from 0.4 to 3% by weight.

11. Composition according to one of the preceding claims, characterized in that it comprises an aqueous phase comprising water and optionally an organic solvent soluble in water, at 25°C, chosen for example from polyols; linear or branched C2-C4 alkanols, such as ethanol and isopropanol, propanol, butanol; and mixtures thereof; and / or an oily phase.

12. Composition according to one of the preceding claims, characterized in that it is an oil-in-water emulsion.

13. Cosmetic process for caring for keratin materials, preferably the skin, comprising the application to said keratin materials of a composition according to one of the preceding claims.