Composition comprising an association of particles

Abstract

Composition comprising an association of particles. The present invention relates to a composition comprising, in a physiologically acceptable medium: (a) at least one particle having a size D[50] less than 3 µm and a refractive index greater than 1.6; and (b) optionally at least one particle having a size D[50] greater than 5 µm; the composition having a dry extract of at most 40% by weight relative to the total weight of the composition. Figure: none

Description

Title of the invention: Composition comprising a combination of particles

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

[0002] (a) at least one particle having a size D

[50] less than 3 pm and having a refractive index greater than 1.6; and

[0003] (b) optionally at least one particle having a size D

[50] greater than 5 pm ;

[0004] the composition having a dry extract at most equal to 40% by weight relative to the total weight of the composition.

[0005] The present invention also relates to a cosmetic process for caring for keratin materials, preferably the skin, comprising the application to said keratin materials of a composition according to the invention.

[0006] Cosmetic compositions for skin care or makeup generally aim to unify the complexion. In particular, they aim to mask and / or blur imperfections. This blurred effect which camouflages the micro-reliefs of the skin is also called the soft-focus effect.

[0007] In cosmetics, the search for soft-focus properties to mask imperfections is a real challenge.

[0008] To add blurred effects and obtain a soft-focus effect, it is conventionally known to use diffusing particles in sufficient quantity having a size D

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

[0009] These particles also make it possible to reduce the visibility of imperfections in the relief of the skin without causing any whitening or modulation of the initial color of the skin.

[0010] However, such particles can cause problems of comfort and sensoriality during application. Indeed, these particles are generally added in a significant quantity, which causes these cosmetic inconveniences. Furthermore, the use of a significant quantity of these particles leads to a reduction in the opacity of the compositions.

[0011] There is therefore a need for compositions having an improved soft-focus effect and providing controlled opacity. Such a composition then allows a total expression of the optical properties of the particles and thus the blurring of imperfections such as wrinkles, fine lines and / or pores.

[0012] The present invention solves this problem.

[0013] Indeed, the Applicant has now discovered that the combination of different optical fillers with different physicochemical properties makes it possible to implement a formula allowing a cosmetic deposit whose optical blurring performance is improved and whose opacity is controlled.

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

[0015] (a) at least one particle having a size D

[50] less than 3 pm and having a refractive index greater than 1.6;

[0016] (b) optionally at least one particle having a size D

[50] greater than 5 pm ;

[0017] the composition having a dry extract at most equal to 40% by weight relative to the total weight of the composition.

[0018] By “physiologically acceptable” is meant a medium compatible with keratin materials.

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

[0020] The composition is preferably in the form of an emulsion, more preferably direct (oil-in-water).

[0021] In the present application, the terms “particle” and “charge” are used interchangeably.

[0022] Preferably, the composition according to the invention is substantially free of silicone particles. Preferably, the composition according to the invention is substantially free of silicone.

[0023] By "substantially free of silicone particles" is meant that the composition comprises less than 1% by weight relative to the total weight of the composition, preferably less than 0.5% by weight, preferably less than 0.3% by weight, preferentially 0.1% by weight of silicone particles. Preferably, the composition is completely free of silicone particles.

[0024] By “silicone particle” is meant an organic or inorganic particle, comprising at least one silicone derivative or having been modified by a silicone group.

[0025] By "substantially free of silicone" is meant that the composition comprises less than 1% by weight relative to the total weight of the composition, preferably less than 0.5% by weight, preferably less than 0.3% by weight, preferentially 0.1% by weight of silicone. Preferably, the composition is completely free of silicone. By silicone is meant any silicone compound. Particle (a)

[0026] The composition according to the invention comprises at least one particle having a size D

[50] less than 3 pm and having a refractive index greater than 1.6.

[0027] Preferably, the particle (a) has a size D

[50] of between 0.1 pm and 2.8 pm, preferably of between 0.2 pm and 2.7 pm and preferably of between 0.4 pm and 2.5 pm.

[0028] The particle size is that given by the statistical distribution to half of the population, called D

[50] . According to the invention, the D

[50] is therefore in number of particles. The particle size is measured by laser diffraction granulometry. The granulometric measurements are carried out on a Malvem 3000 granulometer (laser diffraction) equipped with a 3000G hydro crosslinking tank.

[0029] The Mastersizer uses laser diffraction to measure particle size. This technique involves measuring the intensity of scattered light as a laser beam passes through a sample of dispersed particles. This data is then analyzed to calculate the particle size.

[0030] The refractive index np^ticuies CS( calculated from the composition of the materials in volume proportion, defined by the following equation with ni the index of the material i and the volume fraction of the material i in the particle:

[0031] [Math.l]

[0032] The particle (a) has a refractive index greater than 1.6. Preferably, the particle has a refractive index of between 1.65 and 2.8, more preferably between 1.7 and 2.5.

[0033] 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.

[0034] Preferably, the particles (a) are mineral particles essentially consisting of mineral oxide and / or hydroxides.

[0035] According to a preferred embodiment, the particles (a) are boron nitride particles.

[0036] Preferably, the particles are white in color.

[0037] As particles which can be used according to the invention, mention may be made of:

[0038] - boron nitride particles marketed by Saint Gobain under the name SP1. They have a D

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

[0039] - the particles marketed under the name Boron Nitride Powder Very BN PUHP 3002 by Saint Gobain Ceramics. These particles are boron nitride platelets / lamellae. They have a refractive index of 1.74 and a D

[50] size of 2 pm.

[0040] Preferably, the composition according to the invention comprises a concentration of particle (a) ranging from 0.1% to 5% by weight relative to the total weight of the composition, preferably between 0.2% and 3% by weight, and even more preferably between 0.5% and 2.5% by weight. Particle (b)

[0041] Preferably, the composition according to the invention comprises at least one particle (b) having a size D

[50] greater than 5 pm.

[0042] Preferably, the particle (b) has a size D

[50] greater than 6 pm, and preferably greater than 8 pm and less than 15 pm.

[0043] The particle (b) may be chosen from cellulose particles, silicas, rice hull powder and mixtures thereof.

[0044] Preferably, the composition according to the invention comprises a concentration of particle (b) ranging from 0.1% to 5.1% by weight relative to the total weight of the composition, preferably between 0.5% and 4% by weight, and even more preferably between 1% and 3% by weight. Cellulose particles

[0045] The cellulose particles which can be used according to the invention are preferably spherical (cellulose beads).

[0046] As used herein, the term "cellulose" refers to any polysaccharide compound having in its structure sequences of glucose residues linked together by b-1,4 linkages, and in addition to unsubstituted celluloses, a derivative thereof may be used. For example, cellulose ethers, cellulose esters, and cellulose ester ethers may be used.

[0047] For the purposes of the present invention, spherical particles are understood to mean solid or porous particles having a circularity parameter of at least 0.95. The circularity parameter is defined as the ratio of the circumference of a disk having the same area as the particle to the perimeter of the particle. A value of 1 characterizes perfectly spherical particles.

[0048] Among the cellulose particles which can be used according to the invention, mention may be made in particular of those sold by the company Daito under the brand name CELLULOBEADS® such as CELLULOBEADS D-5® (D

[50] < 10 pm), CELLULOBEADS D-10® (D

[50] < 15 pm). Silica particles

[0049] Preferably, the composition according to the invention comprises at least one silica particle.

[0050] By "silica particle" is meant porous inorganic silica particles.

[0051] The term "inorganic" means any compound or polymer whose chemical structure does not contain a carbon atom.

[0052] Preferably, the silica particles used in the composition according to the invention are natural and unmodified silica particles.

[0053] As an example of a silica particle, mention may be made of porous spherical silica particles having a size expressed in volume average diameter D

[50] of the particle greater than 5 μm.

[0054] In the present application, the term "spherical particles" means particles having the shape or substantially the shape of a sphere, insoluble in the medium of the composition according to the invention, even at the melting temperature of the medium (approximately 100°C).

[0055] Preferably, the silica particles according to the invention have a specific surface area ranging from 30 to 1000 m2 / g, and more particularly from 150 to 800 m2 / g.

[0056] According to another preferred embodiment, the silica particles according to the invention have a specific surface area greater than 90 m2 / g.

[0057] As an example of porous silica microbeads, the following commercial products can be used: Silica Beads SB-150, SB-300 or SB-700, preferably SB-300 from the company MYOSHI KASEI; the SUNSPHERE range from the company Asahi Glass AGC SI-TECH, in particular the Sunsphere H-51 or the Sunsphère 12L, Sunsphère H-201, H-52 and H-53; Sunsil 130 from the company Sunjin; Spherica P-1500 from the company Ikeda Corporation; Sylosphere from the company Fuji Silysia; the Silica Pearl and Satinier ranges from JGC Catalysts and Chemicals, more specifically Satinier M13 and M16, MSS-500 silicas from KOBO, more specifically MSS-500-20N, as well as Silica Shells from KOBO.

[0058] Particle (b) may also be a rice hull powder. Such a powder is preferably a vegetable silica. The INCI name and / or chemical name may be Oryza Sativa (Rice) Hull Powder or Silica (INCI) and Rice Bran Oil or Silicon Dioxide (CAS). Such a rice hull powder is a mineral or vegetable particle, composed of at least 99% SiO2, whose average size D

[50] is greater than 5 pm, and which has a tapped density of less than 0.3 g.cm3 (0.26) and a specific surface area greater than 90 m2 / g.

[0059] The protocol for measuring the packed density is as follows:

[0060] The sample is aerated and homogenized in a bottle before sampling, by rolling the bottle between the fingers. A 25ml glass test tube is filled with powder through a plastic funnel to avoid clumps, avoiding any shock, up to a height of 25ml. The mass is retained. The powder test tube is then placed on a compacting device, for 1500 strokes. The compacted volume is retained. The compacted density is calculated as the ratio between the retained mass and the retained volume. The measurements are duplicated. Dry extract

[0061] The composition according to the invention comprises a dry extract content (or dry formula rate) at most equal to 40% by weight relative to the total weight of the composition.

[0062] The composition according to the invention advantageously comprises a dry extract content (or dry formula rate) of between 10% and 40% by weight, better still between 15% and 35% by weight, in particular between 20% and 30% by weight relative to the total weight of the composition.

[0063] For the purposes of the present invention, the "dry extract content" designates the content of non-volatile matter. The quantity of dry extract (abbreviated ES) of a composition according to the invention is measured using a commercial halogen desiccator "HALOGEN MOISTURE ANALYZER HR 73" from METTLER TOLEDO. The measurement is based on the weight loss of a sample dried by halogen heating and therefore represents the percentage of residual matter once the water and volatile matter have evaporated. This technique is fully described in the documentation for the device provided by METTLER TOLEDO.

[0064] The measurement protocol is as follows: Approximately 2 g of the composition, hereinafter the sample, are spread on a metal dish which is introduced into the halogen desiccator mentioned above. The sample is then subjected to a temperature of 105°C until a constant weight is obtained. The Wet Mass of the sample, corresponding to its initial mass, and the Dry Mass of the sample, corresponding to its mass after halogen heating, are measured using a precision balance. The experimental error related to the measurement is of the order of plus or minus 2%. The Dry Extract content is calculated as follows: Dry Extract Content (expressed in % by weight) = 100 x (Dry Mass / Wet Mass). Aqueous phase

[0065] The composition according to the invention may comprise an aqueous phase.

[0066] The aqueous phase comprises 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.

[0067] By polyol is meant a hydrocarbon chain comprising at least 2 carbon atoms, preferably from 2 to 50 carbon atoms, preferably from 4 to 20 carbon atoms, preferably having from 2 to 10 carbon atoms, and preferentially having from 2 to 6 carbon atoms, and carrying at least two hydroxyl groups. The polyols used in the present invention may have a mass weight average molecular weight less than or equal to 1000, preferably between 90 and 500. The polyol may be a natural or synthetic polyol. The polyol may have a linear, branched or cyclic molecular structure.

[0068] The polyol may be selected from glycerin and derivatives thereof, and glycols and derivatives thereof. 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, especially having from 5 to 50 ethylene oxide groups, and sugars such as sorbitol, and mixtures thereof. Preferably, the polyol is glycerin.

[0069] 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 preferentially ranging from 5% to 20% by weight.

[0070] 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.

[0071] Preferably, the composition according to the invention further comprises an oily phase.

[0072] Preferably, the composition according to the invention is an oil-in-water emulsion. Oily phase

[0073] 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, the latter preferably contains at least one oil, in particular a cosmetic oil. It may also contain other fatty substances.

[0074] By "oil" is meant a non-aqueous compound, liquid at 25°C and atmospheric pressure (1,013.105 Pa), immiscible with water.

[0075] 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 by eye or by means of a phase contrast microscope if necessary, on 100g of mixture obtained after Rayneri stirring sufficient to cause a vortex to appear within the mixture (for information 200 to 1000 rpm); the resulting mixture being left to stand, in a closed bottle, for 24 hours at room temperature before observation.

[0076] As oils which can be used in the composition of the invention, we can cite for example:

[0077] - hydrocarbon oils of animal origin, such as perhydrosqualene;

[0078] - hydrocarbon oils of vegetable origin, such as liquid triglycerides fatty acids containing 4 to 10 carbon atoms such as triglycerides of heptanoic or octanoic acids or, for example, sunflower, corn, soybean, pumpkin, grape seed, sesame, hazelnut, apricot, macadamia, arara, sunflower, castor, avocado oils, 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;

[0079] - synthetic esters and ethers, in particular of fatty acids, such as oils of formulas R1COOR2 and R1OR2 in which RI represents the residue of a fatty acid containing from 8 to 29 carbon atoms, and R2 represents a hydrocarbon chain, branched or not, containing from 3 to 30 carbon atoms, such as for example Purcellin oil, isononyl isononanoate, isopropyl myristate, 2-ethylhexyl palmitate, 2-octyldodecyl stearate, 2-octyldodecyl erucate, isostearyl isostearate; hydroxylated esters such as isostearyl lactate, octylhydroxystearate, octyldodecyl hydroxystearate, diisostearylmalate, triisocetyl citrate, fatty alcohol heptanoates, octanoates, decanoates; polyol esters, such as propylene glycol dioctanoate, neopentyl glycol diheptanoate and diethylene glycol diisononanoate; and pentaerythritol esters such as pentaerythrityl tetraisostearate or dipentaerythrityl pentaisononanoate;

[0080] - 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, Parléam® marketed by the company NIPPON OIL FATS, PANALANE H-300 E marketed by the company AMOCO, VISEAL 20000 marketed by the company SYNTEAL, REWOPAL PIB 1000 marketed by the company WITCO, or PARLEAM LITE marketed by NOF Corporation;

[0081] - partially hydrocarbon and / or silicone fluorinated oils such as those described in document JP-A-2-295912;

[0082] - silicone oils such as volatile or non-volatile polymethylsiloxanes (PDMS) linear or cyclic silicone chain, liquid or pasty at room temperature, in particular cyclopolydimethylsiloxanes (cyclomethicones) such as cyclohexasiloxane; polydimethylsiloxanes comprising 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, phenyldime- thicones, phenyltrimethylsiloxydiphenylsiloxanes, diphenyldimethicones, diphenylmethyldiphenyl trisiloxanes, 2-phenylethyltrimethylsiloxysilicates, and polymethylphenylsiloxanes; or

[0083] - their mixtures.

[0084] As indicated above, the composition according to the invention may comprise, in the oily phase, other fatty substances. Preferably, this fatty substance is chosen from fatty alcohols having from 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, oleyl alcohol or linoleyl alcohol.

[0085] The amount of oily phase may 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 the composition.

[0086] The composition of the invention may also contain adjuvants usual in the cosmetic and / or dermatological fields, such as active ingredients, preservatives, antioxidants, complexing agents, pH adjusters (acidic or basic), perfumes, odor absorbers or coloring materials (pigments and dyes).

[0087] The quantities of these different adjuvants are those conventionally used in the field considered, 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 fatty phase and / or into the aqueous phase.

[0088] The present invention also relates to a cosmetic process for caring for keratin materials, preferably the skin, comprising the application to said keratin materials of a composition according to the invention.

[0089] The following examples of compositions according to the invention are given by way of illustration and without limitation.

[0090] The quantities are given in % by weight of the total weight of the composition (% w / w), unless otherwise stated.

[0091] Examples: preparations and evaluations of compositions METHODS Laser diffraction particle size analysis

[0092] The particle size measurements were carried out on a Malvem 3000 particle size analyzer (laser diffraction) equipped with a 3000G hydro crosslinking tank. The Mastersizer uses laser diffraction to measure particle size. This technique involves measuring the intensity of the scattered light when a laser beam passes through a sample of dispersed particles. This data is then analyzed to calculate the particle size. Haze measurement

[0093] 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 hemispherical (or total) transmittance. The higher the transmittance of a material, the more transparent it is.

[0094] The Haze-Gard® measures the Direct Transmittance (TD, i.e. in the same direction as the incident ray) or Hemispherical Transmittance (TH, in all directions in space, which is equivalent to the total transmittance) separately. The more hemispherical the transmittance of a material is compared to the direct transmittance, the more it has a "blurring" effect.

[0095] We define the Haze value (%) to highlight this relationship between hemispherical transmittance and direct transmittance. Thus, the higher a material's Haze value, the higher its "blur" (or soft focus) effect.

[0096] [Math.2] to(%)=100 * (TH -I0XTH

[0097] The product is deposited in a controlled thickness of 25 μm using an automatic spreader (Byko drive®) on a transparent plastic film of 50 μm. After a drying time of 1 hour at room temperature and in the open air, the optical parameters (T, H) are measured using the Haze-Gard, at three separate points on the deposit in order to obtain an average. The state of the film is also characterized. For the measurements to be relevant, the deposit must be uniform, without streaks or heterogeneity. Opacity Measurement

[0098] 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).

[0099] 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.

[0100] From these parameters, we can then determine the contrast ratio (CR) which we define as:

[0101] [Math.3] ïiw CR = — * 100

[0102] 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 greater the product will tend to provide colonial coverage.

[0103] The coverage effectiveness rate (Coverage Effectiveness) is defined as the CR / TD ratio.

[0104] Any cosmetic composition which simultaneously meets the two conditions below is considered to be according to the invention: - Haze > 60% (hiding imperfections) and Direct Transmittance (DT) > 85% (non-bleaching); and - 0.05 < Coverage Efficiency <0.1: opacity without whitening. Preparation of compositions

[0105] The comparative compositions and those according to the invention are prepared by mixing the ingredients mentioned in water according to Table 1 and Table 2.

[0106] Compositions according to the invention Ingrédients Inv.l BN3 Inv.2 BN5 Inv.3 BN6 Inv.4 BN8 Inv.5 BN10 Inv.6 BN7 Potassium Hydroxide 0.2 0.2 0.2 0.2 0.1 0.2 Stearic Acid 1.6 1.6 1.6 1.5 0.4 1.6 PEG-100 Stearate and Glyceryl Stearate 2.25 2.25 2.25 2.2 0.6 2.25 Preservative Qs Qs Qs Qs Qs Qs Qs Perfume 0.20 0.20 0.20 0.20 0.10 0.20 Xanthan Gum 0.1 0.1 0.1 0.1 - 0.1 Glycerin 7.00 6.9 6.9 6.7 2.00 7 Polyacrylamide and Laureth 7 1.5 1.5 1.5 1.4 0.4 1.5 Acrylates / C10-30 alkyl acrylate crosspolymer 0.20 0.20 0.20 0.20 0.10 0.20 Poly C10-30 alkyl acrylate 1.1 1.1 1.1 1.1 0.3 1.1 Cetyl alcohol 1.3 1.3 1.3 1.3 0.4 1.3 Hydrogenated jojoba oil 1.20 1.20 1.20 1.2 0.3 1.20 Biosaccharide gum-1 (Solabia Fucogel 1000) 2.0 2.0 2.0 1.9 0.6 2.0 Dipentaerythrityl hexacaprylate / Hexacaprate 0.50 0.50 0.50 0.5 0.1 0.50 Ethylenediamine trisodium disuccinate 0.10 0.10 0.10 0.10 0.10 0.10 Octyldodecanol 2.00 2.00 2.00 1.9 0.6 2.00 Poloxamer 338 0.3 0.3 0.3 0.3 0.1 0.3 Butylene glycol 2 2 2 1.9 0.6 2 Tetradecane (and) octyl-dodecanol 1 1 1 1.0 1 1 . Boron nitride particle (a) (Boron Nitride Powder Very BN PUHP 3002 from Saint Gobain Ceramics) 1 2.1 2 0.6 0.6 2 Rice hull powder (b) (Oryza sativa hull powder) 2 2 2 5.1 2 - Water Qsp 100 Qsp 100 Qsp 100 Qsp 100 Qsp 100 Qsp 100 Dry extract (%) 28.7 28.4 28.4 30.3 9.8 27.6

[0108] Oryza sativa hull powder = silica particles (b) RICESILK from Soliance, which have a size D

[50] of 10 pm

[0109] Comparative compositions

[0110] [T ables 2] Ingredients Comp.l BN1 Comp.2 BN2 Comp.3 BN4 Comp.4 BN9 Comp.5 BN11 Potassium Hydroxide 0.2 0.2 0.2 0.2 0.2 Stearic Acid 1.63 1.60 1.60 1.3 1.6 PEG-100 Stearate and Glyceryl Stearate 2.29 2.25 2.3 1.8 2.2 Preservative Qs Qs Qs Qs Qs Perfume 0.20 0.20 0.20 0.2 0.2 Xanthan Gum 0.15 0.15 0.15 0.15 0.1 Glycerin 7.12 7.00 7.00 5.7 7.0 Polyacrylamide and Laureth 7 1.53 1.5 1.5 1.2 1.5 Acrylates / C10-30 alkyl acrylate crosspolymer 0.20 0.20 0.20 0.20 0.20 Poly C10-30 alkyl acrylate 1.17 1.15 1.2 0.9 1.1 Cetyl alcohol 1.37 1.35 1.4 1.1 1.3 Hydrogenated jojoba oil 1.22 1.20 1.20 1.0 1.20 Biosaccharide gum-1 (Solabia Fucogel 1000) 2.03 2.0 2.0 1.6 2.0 Dipentaerythrityl hexacaprylate / Hexacaprate 0.51 0.50 0.50 0.50 0.50 Ethylene disuccinate diamine trisodium 0.10 0.10 0.10 0.10 0.10 Octyldodecanol 2.03 2.00 2.00 1.6 2.00 Poloxamer 338 0.31 0.3 0.3 0.2 0.3 Butylene glycol 2 2 2 1.6 2 Tetradecane (and) octyl-dodecanol 1.02 1 1 0.8 1 Nitride particle of - - 0.09 0.6 - 。 Boron (a) (Boron Nitride Powder Very BN PUHP 3002 from Saint Gobain Ceramics) Boron nitride particle (a') (Softouch Boron Nitride Powder CC6058 from Momentive Performance Materials) 2 Rice hull powder (b) (Oryza sativa hull powder) - 1 1 2 - Water Qsp 100 Qsp 100 Qsp 100 Qsp 100 Qsp 100 Dry extract (%) 26.1 26.7 26.9 40.6 28.4

[0111] Oryza sativa hull powder = silica particles (b) RICESILK from Soliance, which have a size D

[50] of 10 pm

[0112] Compositions Comp. 1, Comp. 2 and Comp. 5 are comparative because they do not contain particle (a). Comp. 5 also contains particles (a').

[0113] Composition Comp.3 is comparative because it contains less than 0.1% by weight of particle (a).

[0114] Composition Comp.4 is comparative because it has a dry extract greater than 40%.

[0115] The compositions Inv.1 to Inv.6 according to the invention comprise a particle (a), optionally a particle (b) (Inv.1 to Inv.5) and have a maximum dry extract of 40%.

[0116] The physicochemical parameters of the different fillers used in the compositions according to the invention and comparative ones are summarized in Table 3.

[0117] [Tables3] Fillers Size D

[50] (pm) Refractive Index Boron Nitride Particle (a) (Boron Nitride Powder Very BN PUHP 3002 from Saint Gobain Ceramics) 2 1.74 Boron Nitride Particle (a') (Softouch Boron Nitride Powder CC6058 from Momentive Performance Materials) 5-15 1.74 Rice Hull Powder (b) (Oryza sativa hull powder) 9.85 1.45

[0118] Oryza sativa hull powder = silica particles (b) RICESILK from Soliance, which have a size D

[50] of 10 pm

[0119] The boron nitride particles (a) according to the invention have a refractive index of 1.74 and an average size of 2 pm. The comparative boron nitride particles (a') have a refractive index of 1.74 and an average size of between 5-15 pm. Results

[0120] The results of all the tests are summarized in Table 4 below:

[0121] [Tables4] Compositi on Inv. 1 BN3 Inv.2 BN5 Inv.3 BN6 Inv.4 BN8 Inv.5 BN1 0 Inv.6 BN7 Comp pl BN1 Comp p.2 BN2 Comp p.3 BN4 Comp p.4 BN9 Comp p.5 BN11 Particle rate a) 1 2.1 2 0.6 0.6 2 - - 0.09 0.6 - Particle rate b) 2 1 1 5.1 2 - - 1 1 2 - Dry extract (%) 28.7 28.42 28.35 30.3 9.8 27.6 26.14 26.70 26.94 40.61 27.61 Haze 79.5 72.7 73.6 75.30 77.10 67 41.5 50 43.4 35.7 40.5 TD 88.7 0 88.50 88.20 92 91.6 89.1 91.60 92.00 92.60 91.20 91.40 CR 7.07 7.97 8.13 5.7 6.36 7.19 4.40 4.447 4.36 3.48 5.45 Effectiveness Coverage 0.08 0.09 0.092 0.062 0.069 0.081 0.048 0.049 0.047 0.038 0.06

[0122] It emerges from these results that only the compositions comprising a combination of at least 0.1% by weight of particles a) having a size D

[50] of between 100 nm and 5 pm and having a refractive index greater than 1.6 and optionally a particle b) having a size D

[50] greater than 5 pm, with a dry extract of at most 40%, exhibit both good dispersion and the desired optical properties.

[0123] Furthermore, the inventors have shown that the use of larger-sized particles (particle a')) which do not meet the specifications of the invention (i.e. in terms of size) (cf Comp.5 BN11) has opacity properties which are not as effective (Coverage efficiency 0.060 and Haze 40.5).

[0124] Similarly, the inventors have demonstrated that a composition comprising a dry extract greater than 40% (Comp. 4 BN9) has reduced optical properties compared to the compositions according to the invention Inv.1, Inv.2 and Inv.3, Inv.4, Inv.5 and Inv.6.

Claims

Claims

1. Composition comprising, in a physiologically acceptable medium: (a) at least 0.1% by weight relative to the total weight of the composition of at least one particle having a size D[50] less than 3 pm and having a refractive index greater than 1.6; and (b) optionally at least one particle having a size D[50] greater than 5 pm; the composition having a dry extract at most equal to 40% by weight relative to the total weight of the composition.

2. Composition according to claim 1, characterized in that it comprises a concentration of particle (a) ranging from 0.1% to 5% by weight relative to the total weight of the composition, preferably between 0.2% and 3% by weight, and even more preferably between 0.5% and 2.5% by weight.

3. Composition according to claim 1 or 2, characterized in that the particle (a) has a size D[50] of between 0.1 pm and 2.8 pm, preferably between 0.2 pm and 2.7 pm and even more preferably between 0.4 pm and 2.5 pm.

4. Composition according to one of the preceding claims, characterized in that the particle (a) has a refractive index of between 1.65 and 2.8, more preferably between 1.7 and 2.

5.

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

6. Composition according to one of the preceding claims, characterized in that particle (b) has a size D[50] greater than 6 pm, and preferably greater than 8 pm and less than 15 pm.

7. Composition according to one of the preceding claims, characterized in that it comprises a concentration of particle (b) ranging from 0.1% to 5.1% by weight relative to the total weight of the composition, preferably between 0.5% and 4% by weight, and even more preferably between 1% and 3% by weight.

8. Composition according to one of the preceding claims, characterized in that the particle (b) is chosen from cellulose particles, silica particles, rice hull powder and mixtures thereof.

9. Composition according to one of the preceding claims, characterized in that it comprises less than 1% by weight relative to the total weight of the composition, preferably less than 0.5% by weight, preferably less than 0.3% by weight, preferably 0.1% by weight of silicone particles, preferably the composition is completely free of silicone particles.

10. Composition according to any one of the preceding claims, characterized in that the dry extract is between 10% and 40%, preferably between 15% and 35% by weight relative to the total weight of the composition, preferably between 20% and 30% 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; alkanols, linear or branched and / or an oily phase.

12. 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.