WO2013160361A2

WO2013160361A2 - Composition comprising a silane and a polysaccharide bearing hydrophobic groups

Info

Publication number: WO2013160361A2
Application number: PCT/EP2013/058515
Authority: WO
Inventors: Raluca Lorant; Mathieu CHABRILLANGEAS; Nathalie GUILLIER
Original assignee: LOreal SA
Current assignee: LOreal SA
Priority date: 2012-04-26
Filing date: 2013-04-24
Publication date: 2013-10-31
Anticipated expiration: 2014-10-26
Also published as: WO2013160361A3; FR2989885A1

Description

Composition comprising a silane and a polysaccharide bearing

hydrophobic groups The present patent application relates to a composition comprising a silane and a polysaccharide bearing hydrophobic groups, and to the use of the said composition in cosmetics and dermatology, in particular for caring for or treating keratin materials.

For a few years, consumers are increasingly in search of products containing ingredients of natural origin. Consumers desire formulations free of chemical substances, to which they prefer ingredients of natural origin, renowned for their better tolerance and affinity with the skin. Consumers desire formulations stabilized with emulsifiers that are gentle on the skin, well tolerated and preferably derived from plants.

Hydrophobic-modified polysaccharides are increasingly used in cosmetics for stabilizing direct emulsions or even inverse emulsions. Thus, patent FR 2925362 describes the use of these compounds for improving the stability of inverse emulsions comprising a polyglyceryl stearate.

However, these polysaccharides have the drawback of giving compositions that do not always have good cosmetic properties, in particular: a non-glidant feel on application - which makes the application difficult and may be associated with a final sensation of non-moisturized, dry skin; hydrophobic-modified polysaccharides have a tacky feel on application and after penetration into the skin, especially when these materials are used in amounts exceeding 1 -2%; which is often necessary to ensure good stability and/or a thickening effect of the composition.

There is thus still a need for compositions

that are stabilized and/or thickened with polymers of natural origin, which show good harmlessness towards keratin materials, for instance the skin, - and which afford satisfactory sensory properties, such as good glidance on application and a soft, non-tacky skin finish. The cosmetic properties sought are a soft and pleasant feel on application, no dragging or coarse effect, and good glidance during application and after application to keratin materials and more particularly the skin.

The object of the invention is to be able to prepare compositions, especially emulsions, with good cosmetic properties without having the drawbacks of the prior art.

The Applicant has discovered, surprisingly, that this problem can be solved by combining at least one polysaccharide bearing hydrophobic groups and at least one particular silane.

One subject of the present invention is thus a composition, especially in the form of an emulsion, comprising at least one silane of formula (I) as described below and at least one polysaccharide bearing hydrophobic groups, the silanes of formula (I) and/or oligomers thereof being present in an active material content ranging from 2% to 20% by weight relative to the total weight of the composition.

This composition may be obtained by mixing at least one silane as described below and at least one polysaccharide bearing hydrophobic groups.

Since the composition of the invention is intended especially for topical application, it comprises a physiologically acceptable medium, i.e. a medium that is compatible with all keratin materials such as the skin, the nails, mucous membranes and keratin fibres (such as the hair or the eyelashes).

The composition obtained according to the invention has the advantage of having a homogeneous, non-tacky texture and of being very gentle on application to the skin and after penetration of the product, without a dragging or coarse effect on the skin.

The compositions spread particularly well on keratin materials such as the skin and the hair.

A subject of the invention is also a cosmetic process for treating keratin materials, which consists in applying to the keratin materials a composition as defined above.

Silane The silanes that may be used in the composition according to the invention are those corresponding to formula (I) below and/or oligomers thereof:

RiSi(OR₂)_z(R₃)x(OH)_y (I)

in which:

· Ri is a linear or branched, saturated or unsaturated C1 -C22 hydrocarbon-based chain, C3-C40 cycloalkyl or C6-C30 aromatic; optionally substituted with a hydroxyl group, a thiol group, an aryl group (more particularly benzyl), which is substituted or unsubstituted; Ri possibly being interrupted with a heteroatom (O, S or NH) or a carbonyl group (CO),

• R₂ and R3, which may be identical or different, represent a linear or branched alkyl group comprising from 1 to 6 carbon atoms,

• y denotes an integer ranging from 0 to 3, and

• z denotes an integer ranging from 0 to 3, and

· x denotes an integer ranging from 0 to 2,

• with z+x+y=3.

The term "oligomer" means the polymerization products of the compounds of formula (I) comprising from 2 to 10 silicon atoms.

Preferably, R2 represents an alkyl group comprising from 1 to 4 carbon atoms, better still a linear alkyl group comprising from 1 to 4 carbon atoms, and preferably the ethyl group.

Preferably, R3 represents an alkyl group comprising from 1 to 4 carbon atoms, better still a linear alkyl group comprising from 1 to 4 carbon atoms, and preferably methyl or ethyl groups.

Preferably, Ri represents an alkyl group, and even more preferentially a linear alkyl group, comprising from 7 to 18 carbon atoms and more particularly from 7 to 12 carbon atoms.

Preferably, Ri represents an octyl group.

Preferably, z ranges from 1 to 3. Even more preferentially, z is equal to 3.

Preferably, the composition comprises at least one silane chosen from octyltriethoxysilane, dodecyltriethoxysilane, octadecyltriethoxysilane and hexadecyltriethoxysilane. More particularly, the composition comprises at least octyltriethoxysilane (OTES).

The silanes of formula (I) and/or oligomers thereof may be present in the composition of the invention in an active material content ranging from 2% to 20% by weight and preferentially ranging from 5% to 15% by weight relative to the total weight of the composition.

Polysaccharide bearing hydrophobic groups

Polysaccharides are polymers having monosaccharides or disaccharides as base units.

In general, the compounds of this type that may be used in the present invention are chosen from those described especially in Kirk-Othmer's Encyclopedia of Chemical Technology, Third Edition, 1982, volume 3, pp. 896- 900, and volume 15, pp. 439-458, in Polymers in Nature by E.A. MacGregor and C.T. Greenwood, published by John Wiley & Sons, Chapter 6, pp. 240-328, 1980, and in Industrial Gums - Polysaccharides and their Derivatives, edited by Roy L. Whistler, Second Edition, published by Academic Press Inc.

The polysaccharides are especially chosen especially from fructans, glucans, modified or unmodified starches (such as those derived, for example, from cereals, for instance wheat, corn or rice, from legumes, for instance yellow pea, and tubers, for instance potato or cassava), amylose, amylopectin, glycogen, dextrans, celluloses and derivatives thereof (methylcelluloses, hydroxyalkylcelluloses, ethylhydroxyethylcelluloses, carboxymethylcelluloses), xylans such as arabinoxylans and glucuronoxylans, arabans, galactans, galacturonans, chitin, chitosans, glucans such as xyloglucans and glycosaminoglucans, pectic acids and pectins, alginic acid and alginates, arabinogalactans, carrageenans, agars, gum arabics, gum tragacanths, ghatti gums, karaya gums, locust bean gums, mannans such as glucomannans and galactomannans such as guar gums and nonionic derivatives thereof (hydroxypropyl guar) and xanthan gums, and mixtures thereof.

The hydrophobic groups that may be grafted onto the main chain of the polysaccharide may especially be linear or branched, saturated or unsaturated hydrocarbon-based chains containing from 6 to 50 carbon atoms, preferably C8-C22, such as alkyl, arylalkyl, alkylaryl or alkylene groups; divalent cycloaliphatic groups or organopolysiloxane chains. These hydrocarbon-based or organopolysiloxane chains may especially comprise one or more ester, amide, urethane, carbamate, thiocarbamate, urea, thiourea and/or sulfonamide functions especially such as methylenedicyclohexyl and isophorone; or divalent aromatic groups such as phenylene.

The polysaccharides bearing hydrophobic groups are chosen, for example, from celluloses, guar gums and fructans.

According to the invention, the hydrophobic groups are linear or branched, saturated or unsaturated hydrocarbon-based groups containing from 6 to 50 carbon atoms, such as alkyl, alkyloyloxy, alkyloyl, alkyl carbamate arylalkyl and alkylaryl groups. The aryl radicals preferably denote phenyl, benzyl, naphthyl or anthryl groups.

The celluloses may be chosen from:

- celluloses modified with groups comprising at least one fatty chain, for instance hydroxyethylcelluloses modified with groups comprising at least one fatty chain, such as alkyl, especially of C8-C22, arylalkyl and alkylaryl groups, such as cetyl hydroxyethylcellulose, for instance Polysurf 67 CS or Natrosol Plus Grade 330 CS (C16 alkyls) sold by the company Aqualon,

- celluloses modified with alkylphenyl polyalkylene glycol ether groups, such as the product Amercell Polymer HM-1500® (nonylphenyl polyethylene glycol (15) ether) sold by the company Amerchol,

- quaternized celluloses modified with groups comprising at least one fatty chain, such as alkyl, arylalkyl or alkylaryl groups comprising from 8 to 30 carbon atoms, or mixtures thereof,

- quaternized hydroxyethylcelluloses modified with groups comprising at least one fatty chain, such as alkyl, arylalkyl or alkylaryl groups containing at least 8 carbon atoms, or mixtures thereof.

- The alkyl radicals borne by the above quaternized celluloses or hydroxyethylcelluloses preferably comprise from 8 to 30 carbon atoms. The aryl radicals preferably denote phenyl, benzyl, naphthyl or anthryl groups. - Examples of quaternized alkylhydroxyethylcelluloses containing Cs- C30 fatty chains that may be indicated include the products Quatrisoft LM 200®, Quatrisoft LM-X 529-18-A®, Quatrisoft LM-X 529-18B® (C12 alkyl) and Quatrisoft LM-X 529-8® (Ci₈ alkyl) sold by the company Amerchol, and the products Crodacel QM®, Crodacel QL®

(C12 alkyl) and Crodacel QS® (C18 alkyl) sold by the company Croda. The guar gums bearing hydrophobic groups are especially chosen from hydroxypropyl guars modified with groups comprising at least one fatty chain such as alkyl, arylalkyl or alkylaryl groups comprising from 8 to 30 carbon atoms, such as the product Esaflor HM 22® (C22 alkyl chain) sold by the company Lamberti, and the products RE210-18® (Ci₄ alkyl chain) and RE205- 1 ® (C20 alkyl chain) sold by the company Rhodia Chimie.

The fructans bearing hydrophobic groups are especially chosen from fructans modified with groups comprising at least one C6-C30 fatty chain.

Fructans or fructosans are oligosaccharides or polysaccharides comprising a sequence of anhydrofructose units optionally combined with several saccharide residues other than fructose. Fructans may be linear or branched. Fructans may be products obtained directly from a plant or microbial source or alternatively products whose chain length has been modified (increased or decreased) by fractionation, synthesis or hydrolysis, in particular enzymatic. Fructans generally have a degree of polymerization from 2 to about 1000 and preferably from 2 to about 60.

Three groups of fructans are distinguished. The first group corresponds to products whose fructose units are for the most part linked via β-2-1 bonds. These are essentially linear fructans such as inulins.

The second group also corresponds to linear fructoses, but the fructose units are essentially linked via β-2-6 bonds. These products are levans.

The third group corresponds to mixed fructans, i.e. containing β-2-6 and β-2-1 sequences. These are essentially branched fructans, such as graminans. Inulin may be obtained, for example, from chicory, dahlia or Jerusalem artichoke. Preferably, the inulin used in the composition according to the invention is obtained, for example, from chicory.

Hydrophobic-modified fructans are generally obtained by grafting hydrophobic chains onto the hydrophilic backbone of the fructan.

The hydrophobic chains that may be grafted onto the main chain of the fructan may especially be linear or branched, saturated or unsaturated hydrocarbon-based chains containing from 6 to 50 carbon atoms, such as alkyl, arylalkyl, alkylaryl or alkylene groups; divalent cycloaliphatic groups or organopolysiloxane chains. These hydrocarbon-based or organopolysiloxane chains may especially comprise one or more ester, amide, urethane, carbamate, thiocarbamate, urea, thiourea and/or sulfonamide functions especially such as methylenedicyclohexyl and isophorone; or divalent aromatic groups such as phenylene.

In particular, the inulin has a degree of polymerization from 2 to about

1000 and preferably from 2 to about 60, and a degree of substitution of less than 2 on the basis of a fructose unit.

According to one preferred embodiment, the hydrophobic chains contain at least one alkyl carbamate group of formula R-NH-CO- in which R is an alkyl group containing from 6 to 22 carbon atoms.

According to a more preferred embodiment, the hydrophobic chains are lauryl carbamate groups.

In particular, as non-limiting illustrations of hydrophobic modified inulins that may be used in the compositions according to the invention, mention may be made of stearoyl inulin, such as those sold under the names Lifidrem INST by the company Engelhard and Rheopearl INS by the company Ciba; palmitoyl inulin; undecylenoyl inulin, such as those sold under the names Lifidrem INUK and Lifidrem INUM by the company Engelhard; and inulin lauryl carbamate, such as the product sold under the name Inutec SP1 by the company Orafti.

In particular, an inulin grafted with lauryl carbamate is used, which is derived especially from the reaction of lauryl isocyanate with an inulin, in particular derived from chicory. Examples of these compounds that may especially be mentioned include the product sold under the name Inutec SP1 by the company Orafti.

The polysaccharide(s) bearing hydrophobic groups may be present in the composition according to the invention in a content ranging from 0.01 % to 10% by weight, preferably ranging from 0.05% to 50% by weight and better still ranging from 0.1 % to 2% by weight relative to the total weight of the composition.

According to the invention, the composition preferably comprises at least one aqueous phase and one fatty phase.

The aqueous phase of the compositions according to the invention comprises at least water. According to the formulation form of the composition, the amount of aqueous phase can range from 0.1 % to 99% by weight, preferably from 0.5% to 98% by weight, better still from 30% to 95% by weight and even better still from 40% to 95% by weight, relative to the total weight of the composition. This amount depends on the galenical form of the composition desired. The amount of water may represent all or part of the aqueous phase, and it is generally at least 30% by weight relative to the total weight of the composition.

The aqueous phase may comprise at least one hydrophilic solvent, for instance substantially linear or branched lower monoalcohols containing from 1 to 8 carbon atoms, for instance ethanol, propanol, butanol, isopropanol or isobutanol; polyols such as propylene glycol, isoprene glycol, butylene glycol, glycerol, sorbitol or polyethylene glycols and derivatives thereof, and mixtures thereof.

When it is present, the proportion of the fatty phase of the emulsion may range for example from 1 % to 80% by weight, preferably from 2% to 50% by weight and better still from 5% to 30% by weight relative to the total weight of the composition.

This indicated amount does not comprise the content of lipophilic surfactants.

The nature of the fatty phase (or oily phase) of the emulsion is not critical.

The fatty phase may thus consist of any fatty substance conventionally used in cosmetics or dermatology; it especially comprises at least one oil (fatty substance that is liquid at 25°C). As oils that may be used in the composition of the invention, examples that may be mentioned include:

- hydrocarbon-based oils of animal origin, such as perhydrosqualene;

- hydrocarbon-based oils of plant origin, such as liquid triglycerides of fatty acids comprising from 4 to 10 carbon atoms, such as heptanoic or octanoic acid triglycerides, or alternatively, for example, sunflower oil, maize oil, soybean oil, marrow oil, grape seed oil, sesame seed oil, hazelnut oil, apricot oil, macadamia oil, arara oil, castor oil, avocado oil, caprylic/capric acid triglycerides, 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 and shea butter oil;

- synthetic esters and ethers, especially of fatty acids, for instance the oils of formulae R^aCOOR^b and R^aOR^b in which R^a represents a fatty acid residue containing from 8 to 29 carbon atoms and R^b represents a branched or unbranched hydrocarbon-based chain containing from 3 to 30 carbon atoms, for instance Purcellin oil, isononyl isononanoate, isopropyl myristate, 2-ethylhexyl palmitate, 2-octyldodecyl stearate, 2-octyldodecyl erucate or isostearyl isostearate; hydroxylated esters, for instance isostearyl lactate, octyl hydroxystearate, octyldodecyl hydroxystearate, diisostearyl malate or triisocetyl citrate; fatty alcohol heptanoates, octanoates or decanoates; polyol esters, for instance propylene glycol dioctanoate, neopentyl glycol diheptanoate and diethylene glycol diisononanoate; and pentaerythritol esters, for instance pentaerythrityl tetraisostearate;

- substantially linear or branched hydrocarbons of mineral or synthetic origin, such as volatile or nonvolatile liquid paraffins, and derivatives thereof, petroleum jelly, polydecenes, isohexadecane, isododecane or hydrogenated polyisobutene, such as Parleam® oil;

- fatty alcohols having from 8 to 26 carbon atoms, such as cetyl alcohol, stearyl alcohol and a mixture thereof (cetylstearyl alcohol), octyldodecanol, 2- butyloctanol, 2-hexyldecanol, 2-undecylpentadecanol, oleyl alcohol or linoleyl alcohol;

- alkoxylated and in particular ethoxylated fatty alcohols, such as oleth-12, ceteareth-12 and ceteareth-20; - partially hydrocarbon-based and/or silicone-based fluoro oils, such as those described in the document JP-A-2-295 912. Fluoro oils that may also be mentioned include perfluoromethylcyclopentane and perfluoro-1 ,3- dimethylcyclohexane, sold under the names Flutec PC1^® and Flutec PC3^® by the company BNFL Fluorochemicals; perfluoro-1 , 2-dimethylcyclobutane; perfluoroalkanes such as dodecafluoropentane and tetradecafluorohexane, sold under the names PF 5050^® and PF 5060^® by the company 3M, or bromoperfluorooctyl sold under the name Foralkyl^® by the company Atochem; nonafluoromethoxybutane sold under the name MSX 4518^® by the company 3M and nonafluoroethoxyisobutane; perfluoromorpholine derivatives such as 4- trifluoromethylperfluoromorpholine sold under the name PF 5052^® by the company 3M;

- silicone oils, for instance volatile or non-volatile polymethylsiloxanes (PDMS) with a substantially linear or cyclic silicone chain, which are liquid or pasty at room temperature, especially cyclopolydimethylsiloxanes (cyclomethicones) such as cyclohexadimethylsiloxane and cyclopentadimethylsiloxane; polydimethylsiloxanes comprising alkyl, alkoxy or phenyl groups, which are pendent or at the end of a silicone chain, these groups containing from 2 to 24 carbon atoms; phenylsilicones, for instance phenyl trimethicones, phenyl dimethicones, phenyltrimethylsiloxydiphenylsiloxanes, diphenyl dimethicones, diphenylmethyldiphenyltrisiloxanes or 2-phenylethyl trimethylsiloxy silicates, and polymethylphenylsiloxanes;

- mixtures thereof.

In the list of the abovementioned oils, the term "hydrocarbon-based oil" is understood to mean any oil predominantly comprising carbon and hydrogen atoms, and optionally ester, ether, fluoro, carboxylic acid and/or alcohol groups.

The other fatty substances which can be present in the oily phase are, for example, fatty acids comprising from 8 to 30 carbon atoms, such as stearic acid, lauric acid, palmitic acid and oleic acid; waxes, such as lanolin, beeswax, carnauba wax, candelilla wax, paraffin waxes, lignite or microcrystalline waxes, ceresin or ozokerite, or synthetic waxes, such as polyethylene waxes or Fischer-Tropsch waxes; or petrolatum paste. These fatty substances may be chosen in a varied manner by a person skilled in the art so as to prepare a composition having the desired properties, for example in terms of consistency or texture.

In a known manner, all the compositions of the invention may contain one or more adjuvants that are common in cosmetics and dermatology: hydrophilic or lipophilic gelling agents and/or thickeners; moisturizers; emollients; hydrophilic or lipophilic active agents; free-radical scavengers; sequestrants; antioxidants; preserving agents; acidifying or basifying agents; fragrances; film- forming agents; dyestuffs (pigments such as iron oxides and titanium dioxide, nacres, soluble dyes), and fillers; and mixtures thereof.

The amounts of these various adjuvants are those conventionally used in the fields under consideration. In particular, the amounts of active agents vary according to the desired objective and are those conventionally used in the fields under consideration, and for example from 0.1 % to 20%, and preferably from 0.5% to 10% of the total weight of the composition.

Hydrophilic gelling agents that may be mentioned, for example, include carboxyvinyl polymers such as the Carbopol products (carbomers) and the Pemulen products (acrylate/C io^_C3o-alkylacrylate copolymer); polyacrylamides, for instance the crosslinked copolymers sold under the names Sepigel 305 (CTFA name: polyacrylamide/Ci3-i₄ isoparaffin/Laureth 7) or Simulgel 600 (CTFA name: acrylamide / sodium acryloyldimethyltaurate copolymer/isohexadecane/polysorbate 80) by the company SEPPIC; cellulose derivatives such as hydroxyethylcellulose; polysaccharides and especially gums such as xanthan gum; and mixtures thereof.

Lipophilic gelling agents that may be mentioned include modified clays such as hectorite and derivatives thereof, for instance the products sold under the name Bentone.

The composition according to the invention may also contain adjuvants that are common in the field under consideration, such as emulsifiers, lipophilic gelling agents, waxes, hydrophilic or lipophilic additives, preserving agents, antioxidants, solvents, fragrances, fillers, UVA and/or UVB screening agents (organic or mineral, soluble or insoluble), pigments, fibres, chelating agents, odour absorbers, dyestuffs and other cosmetic active agents. The emulsifiers are generally present in the composition in a proportion ranging from 0.1 % to 30% by weight and preferably from 0.2% to 20% by weight relative to the total weight of the composition.

For the W/O emulsions, examples of emulsifiers that may be mentioned include dimethicone copolyols such as the mixture of cyclomethicone and of dimethicone copolyol, sold under the name DC 5225 C by the company Dow Corning, and alkyl dimethicone copolyols such as the laurylmethicone copolyol sold under the name Dow Corning 5200 Formulation Aid by the company Dow Corning and the cetyl dimethicone copolyol sold under the name Abil EM 90® by the company Goldschmidt, or the mixture polyglyceryl-4 isostearate/cetyl dimethicone copolyol/hexyl laurate sold under the name Abil WE 09 by the company Goldschmidt. One or more co-emulsifiers may also be added thereto. The coemulsifier can advantageously be chosen from the group consisting of polyol alkyl esters. Mention may in particular be made, as polyol alkyl esters, of glycerol and/or sorbitan esters, for example polyglyceryl isostearate, such as the product sold under the name Isolan Gl 34 by the company Goldschmidt, sorbitan isostearate, such as the product sold under the name Arlacel 987 by the company ICI, sorbitan glyceryl isostearate, such as the product sold under the name Arlacel 986 by the company ICI, and mixtures thereof.

Mention may be made, for the O/W emulsions, for example, as emulsifiers, of nonionic surfactants and in particular esters of polyols and of fatty acid having a saturated or unsaturated chain comprising, for example, from 8 to 24 carbon atoms and better still from 12 to 22 carbon atoms, and their oxyalkylenated derivatives, that is to say derivatives comprising oxyethylene and/or oxypropylene units, such as glyceryl esters of Cs-C2₄ fatty acid, and their oxyalkylenated derivatives; polyethylene glycol esters of Cs-C2₄ fatty acid, and their oxyalkylenated derivatives; sorbitol esters of Cs-C2₄ fatty acid, and their oxyalkylenated derivatives; fatty alcohol ethers; sugar ethers of Cs-C2₄ fatty alcohols, and mixtures thereof.

Mention may in particular be made, as glyceryl ester of fatty acid, of glyceryl stearate (glyceryl mono-, di- and/or tristearate) (CTFA name: glyceryl stearate) or glyceryl ricinoleate, and mixtures thereof. Mention may in particular be made, as polyethylene glycol ester of fatty acid, of polyethylene glycol stearate (polyethylene glycol mono-, di- and/or tristearate) and more especially polyethylene glycol 50 OE monostearate (CTFA name: PEG-50 stearate), polyethylene glycol 100 OE monostearate (CTFA name: PEG-100 stearate) and mixtures thereof.

Use may also be made of mixtures of these surfactants, for instance the product comprising glyceryl stearate and PEG-100 stearate, sold under the name Arlacel 165 by the company Uniqema, and the product comprising glyceryl stearate (glyceryl mono/distearate) and potassium stearate, sold under the name Tegin by the company Goldschmidt (CTFA name: glyceryl stearate SE). Mention may be made, as fatty alcohol ethers, for example, of polyethylene glycol ethers of fatty alcohol comprising from 8 to 30 carbon atoms and in particular from 10 to 22 carbon atoms, such as polyethylene glycol ethers of cetyl alcohol, stearyl alcohol or cetearyl alcohol (mixture of cetyl alcohol and stearyl alcohol). Mention may be made, for example, of ethers comprising from 1 to 200 and preferably from 2 to 100 oxyethylene groups, such as those with the CTFA name Ceteareth-20 or Ceteareth-30, and mixtures thereof.

Mention may be made, as examples of sugar mono- or polyalkyi esters or ethers, of methyl glucose isostearate, sold under the name Isolan-IS by the company Degussa Goldschmidt, or else sucrose distearate, sold under the name Crodesta F50 by the company Croda, and sucrose stearate, sold under the name Ryoto sugar ester S 1570 by the company Mitsubishi Kagaku Foods. Mention may also be made of lipoamino acids and their salts, such as monosodium and disodium acylglutamates, for instance, monosodium stearoyl glutamate, sold under the name Amisoft HS-1 1 PF, and disodium stearoyl glutamate, sold under the name Amisoft HS-21 P, by the company Ajinomoto.

As other active agents that may be used in the composition of the invention, examples that may be mentioned include moisturizing agents, such as protein hydrolysates and polyols, for instance glycerol, glycols, for instance polyethylene glycols; natural extracts; anti-inflammatory agents; oligomeric proanthocyannidols; vitamins such as vitamin A (retinol), vitamin E (tocopherol), vitamin B5 (panthenol), vitamin B3 (niacinamide), derivatives of these vitamins (in particular esters) and mixtures thereof; urea; caffeine; depigmenting agents such as kojic acid, hydroquinone and caffeic acid; salicylic acid and derivatives thereof; a-hydroxy acids, such as lactic acid and glycolic acid and derivatives thereof; retinoids, such as carotenoids and vitamin A derivatives; hydrocortisone; melatonin; extracts of algae, of fungi, of plants, of yeasts, of bacteria; steroids; antibacterial active agents, such as 2,4,4'-trichloro-2'- hydroxydiphenyl ether (or triclosan), 3,4,4'-trichlorocarbanilide (or triclocarban) and the acids indicated above, and in particular salicylic acid and derivatives thereof; matting agents, for instance fibres; tensioning agents; and mixtures thereof.

Needless to say, a person skilled in the art will take care to select the optional adjuvant(s) added to the composition according to the invention such that the advantageous properties intrinsically associated with the composition in accordance with the invention are not, or are not substantially, adversely affected by the envisaged addition.

The compositions according to the invention may be in the form of emulsions of liquid or semi-liquid consistency of milk type for example, obtained by dispersing a fatty phase in an aqueous phase (O/W) or conversely (W/O), or suspensions or emulsions of soft, semi-solid or solid consistency of the cream or gel type, or alternatively multiple emulsions (W/O/W or O/W/O), microemulsions, vesicular dispersions of ionic and/or nonionic type, or wax/aqueous phase dispersions. These compositions are prepared according to the usual methods.

According to a preferred embodiment of the invention, the composition is in the form of an O/W emulsion.

In addition, the compositions used according to the invention may be more or less fluid and may have the appearance of a white or coloured cream, an ointment, a milk, a lotion, a serum, a paste or a mousse.

The composition preferably exhibits a skin-friendly pH which generally ranges from 3 to 8 and preferably from 4.5 to 7.

The examples that follow will allow the invention to be understood more clearly, without, however, being limiting in nature. Unless otherwise mentioned, the amounts indicated are percentages by weight. Example 1 : Emulsion

Procedure:

Once the preserving system has been dissolved in water (at the necessary temperature), add phase B to phase A with stirring using a Rayneri blender. Homogenize phase C (at the temperature necessary to have a homogeneous liquid phase). When the mixtures (A+B) and C are homogeneous, form the emulsion in a conventional manner by adding C to (A+B) with stirring using a Rayneri blender. Homogenize until a smooth gel is obtained.

For each of the compositions, the cosmetic properties were evaluated according to the following protocol.

The cosmetic properties on application are evaluated, monadically, by a panel of experts trained in the description of care products. The sensory evaluation of the care products by this panel is performed as follows: the products are conditioned in opaque jars or pump-dispenser bottles depending on the viscosity of the products. Within the same session, the samples are presented in random order to each panellist. 15 experts evaluated the glidance in the following manner: on a hand predeaned with water and liquid soap and wiped dry with a tissue, 0.05 ml of product is applied to the top half of the hand (five cycles with the index and middle fingers). The product is evaluated during the five passes, and 2 minutes after application.

The experts evaluated the following parameters:

- Glidance on application

- The final tackiness of the skin, after penetration

The descriptors are evaluated on a scale at five levels: None, Sparingly, Moderately, Quite, Very.

The descriptor "glidance" is defined as being the ease of application of the product, its ability to cover a defined area and the capacity of the product not to drag on the skin during application.

Results obtained on a panel of 15 experts:

It was found that the formulation according to the invention is easier to apply and is much less tacky than formulation A.

Example 2: Emulsion

The following composition was prepared: C D (invention)

PHASE A

Water qs 100 qs 100

Preserving agents qs qs

PHASE B

Glycerol 10 10

Sodium polyacrylate 0.5 0.5

Xanthan gum 0.3 0.3

PHASE C

Octyltriethoxysilane

10

Polydimethylsiloxane 5 cSt 10

Inulin lauryl carbamate

0.1 0.1

(Inutec SP1 from Orafti)

PHASE D

Ethanol 7 7

Procedure:

Once the preserving system has been dissolved in water (at the necessary temperature), add phase B to phase A with stirring using a Rayneri blender. Homogenize phase C (at the temperature necessary to have a homogeneous liquid phase). When the mixtures (A+B) and C are homogeneous, form the emulsion in a conventional manner by adding C to (A+B) with stirring using a Rayneri blender. Homogenize until a smooth gel is obtained and finally, at room temperature, add phase D.

The cosmetic properties on application are evaluated, monadically, by a panel of experts trained in the description of care products. The sensory evaluation of the care products by this panel is performed as follows: the products are conditioned in opaque jars or pump-dispenser bottles depending on the viscosity of the products.

Within the same session, the samples are presented in random order to each panellist. 15 experts evaluated the glidance in the following manner: on a hand precleaned with water and liquid soap and wiped dry with a tissue, 0.05 ml of product is applied to the top half of the hand (five cycles with the index and middle fingers). The product is evaluated during the five passes, and 2 minutes after application.

The experts evaluated the following parameters:

- Glidance on application

- The final tackiness of the skin, after penetration

It was found that formulation D according to the invention is easier to apply and is much less tacky and more gentle than formulation C after penetration.

The same type of result is obtained by replacing the octyl triethoxysilane with dodecyl triethoxysilane, octadecyl triethoxysilane or hexadecyl

triethoxysilane.

Claims

1 . Cosmetic composition comprising at least one polysaccharide bearing hydrophobic groups and at least one silane corresponding to formula (I) below and/or oligomers thereof:

RiSi(OR₂)_z(R₃)x(OH)_y (I) in which:

• y denotes an integer ranging from 0 to 3, and

• z denotes an integer ranging from 0 to 3, and

· x denotes an integer ranging from 0 to 2,

• with z+x+y=3,

the silanes of formula (I) and/or oligomers thereof being present in an active material content ranging from 2% to 20% by weight relative to the total weight of the composition.

2. Composition according to the preceding claim, characterized in that:

R2 represents an alkyl group comprising from 1 to 4 carbon atoms, better still a linear alkyl group comprising from 1 to 4 carbon atoms and preferably the ethyl group, and R3 represents an alkyl group comprising from 1 to 4 carbon atoms, better still a linear alkyl group comprising from 1 to 4 carbon atoms and preferably methyl or ethyl groups.

3. Composition according to either of Claims 1 and 2, characterized in that Ri represents an alkyl group, more preferentially a linear alkyl group, comprising from 7 to 18 carbon atoms, and even more preferentially octyl.

4. Composition according to Claims 1 to 3, characterized in that z ranges from 1 to 3 and preferably z is equal to 3.

5. Composition according to Claims 1 to 4, characterized in that it comprises at least one silane chosen from octyltriethoxysilane, dodecyltriethoxysilane, octadecyltriethoxysilane and hexadecyltriethoxysilane.

6. Composition according to Claims 1 to 5, characterized in that it comprises at least octyltriethoxysilane.

7. Composition according to one of the preceding claims, characterized in that the silanes of formula (I) and/or oligomers thereof are present in an active material content ranging from 5% to 15% by weight relative to the total weight of the composition.

8. Composition according to any one of the preceding claims, in which the polysaccharides bearing hydrophobic groups are chosen from celluloses, guar gums and fructans.

9. Composition according to any one of the preceding claims, characterized in that the polysaccharides bearing hydrophobic groups are chosen from:

- hydroxyethylcelluloses modified with groups comprising at least one fatty chain such as alkyl, especially of C8-C22, arylalkyi and alkylaryl groups,

- celluloses modified with alkylphenyl polyalkylene glycol ether groups,

- quaternized celluloses modified with groups comprising at least one fatty chain, such as alkyl, arylalkyi or alkylaryl groups comprising at least 8 carbon atoms,

- quaternized hydroxyethylcelluloses modified with groups comprising at least one fatty chain, such as alkyl, arylalkyl or alkylaryl groups, especially of Cs-C22-

10. Composition according to any one of the preceding claims, characterized in that the polysaccharides bearing hydrophobic groups are chosen from hydroxypropyl guars modified with groups comprising at least one fatty chain such as alkyl, arylalkyl or alkylaryl groups comprising from 8 to 30 carbon atoms.

1 1 . Composition according to any one of the preceding claims, characterized in that the polysaccharides bearing hydrophobic groups are chosen from fructans comprising alkyl carbamate groups of formula R-NH-CO- in which R is an alkyl group containing from 6 to 22 carbon atoms.

12. Composition according to any one of the preceding claims, characterized in that the polysaccharides bearing hydrophobic groups are chosen from cetylhydroxyethylcelluloses and inulins grafted with lauryl carbamate.

13. Composition according to any one of the preceding claims, characterized in that the said polysaccharide(s) bearing hydrophobic groups are present in a content ranging from 0.01 % to 10% by weight, preferably ranging from 0.05% to 5% by weight and better still ranging from 0.1 % to 2% by weight relative to the total weight of the composition.

14. Cosmetic composition, characterized in that it may be obtained by mixing at least one silane as described in one of Claims 1 to 7 and at least one polysaccharide bearing hydrophobic groups as described in Claims 1 and 8 to 13.

15. Cosmetic process for treating a keratin material, characterized in that a cosmetic composition as defined in any one of Claims 1 to 14 is applied to the keratin material.

16. Use of a cosmetic composition as defined in any one of Claims 1 to 14, in cosmetics or dermatology, and in particular for caring for, protecting and/or making up bodily or facial skin, or for haircare.