WO2012038880A2

WO2012038880A2 - Cosmetic composition comprising at least one alkylalkoxysilane

Info

Publication number: WO2012038880A2
Application number: PCT/IB2011/054090
Authority: WO
Inventors: Guillaume Kergosien; Ellen Fremont
Original assignee: L'oreal
Priority date: 2010-09-20
Filing date: 2011-09-19
Publication date: 2012-03-29
Also published as: FR2964869A1; FR2964869B1; WO2012038880A3

Abstract

The present invention relates to a cosmetic or dermatological composition of sol/gel type for making up and/or caring for keratin materials, and/or for making up the teeth, characterized in that it is obtained by mixing (a) at least one alkylalkoxysilane of formula R1xSi(OR2)(4-x) or [R1ySiO(4-y)/2]n[R1x(OR2)zSiO(4-x-z)/2]m, (b) at least one alkoxysilane monomer or oligomer of formula R3xSi(OR2)(4-x) or [R3ySiO(4-y)/2]n[R3x(OR2)zSiO(4-x-z)/2]m, (c) at least one acid, in an amount sufficient for the said cosmetic or dermatological composition to have a pH of between 3 and 6, and (d) an amount of water sufficient to enable hydrolysis of the sol/gel reaction. A subject of the invention is also a cosmetic process for coating keratin materials and/or the teeth, which consists in applying the said composition to the said keratin materials and/or teeth, and a kit for coating keratin materials and/or the teeth, comprising at least two different compositions conditioned separately, the said kit comprising components (a) to (d) as defined previously.

Description

COSMETIC COMPOSITION COMPRISING AT LEAST ONE

ALKYLALKOXYSILANE

A subject of the present invention is a cosmetic or dermato logical composition of sol/gel type for making up and/or caring for keratin materials, and/or for making up the teeth.

This composition comprises at least one alkylalkoxysilane, at least one alkoxysilane comprising at least one nucleophilic group, at least one acid giving the composition a precise pH, and an amount of water sufficient for the sol/gel reaction.

The present invention is more particularly directed towards a nail varnish, especially a long-lasting nail varnish.

The present invention also relates to a kit for coating keratin materials and/or the teeth, comprising the compounds of the said composition, and to a cosmetic process for coating keratin materials and/or the teeth using the said kit. The use of sol/gel techniques for the purposes of preparing a cosmetic composition is known per se. A certain number of studies has related to the preparation of such compositions in which takes place a reaction that lead, after drying, to the formation of a hybrid material by polycondensation and crosslinking at the nanometric scale.

Patent application EP 1 172 079 discloses the use of a reaction of sol/gel type that is performed using an organometallic compound which may be obtained by partial or total hydrolysis, and partial or total condensation, of a metallic precursor.

Patent FR 2 799 967 provides a process for improving the transfer-resistance and/or gloss properties of a cosmetic composition, which consists in incorporating into the composition (A) at least one metallic or organometallic compound, and (B) at least one functionalized organic polymer or at least one functionalized silicone polymer other than the preceding compound.

Patent application GB 2 403 406 discloses a skin care composition comprising a functionalised thick liquid silicone resin obtained from a reaction of sol/gel type. This resin does not form a solid film once applied according to the invention.

Patent application FR 2 913 887 concerns gel type compositions comprising a scented substance, said gel being obtained from a reaction of sol/gel type. However, those compositions are already in the form of a gel and thus cannot be applied to the keratin materials and/or to the teeth.

Finally, patent application WO 98/44906 discloses a cosmetic or dermato logical composition suitable for forming a coating on keratin materials via a reaction of sol/gel type obtained by mixing (A) at least one organometallic compound with (B) at least one functionalized organic polymer or at least one functionalized silicone polymer other than the first compound, and (C) an amount of water sufficient to hydrolyse the organometallic compound.

However, the compositions obtained are possibly not acceptably stable over time, and/or may have, once applied, film- forming times that are unsuitable for cosmetic use, especially of several hours or more.

Furthermore, it turns out that these compositions form a film that may show weakness with respect to water resistance.

Finally, it has been found that the wear property of this film may be judged as non-optimal in terms of duration.

There is consequently a need to provide compositions using these sol/gel reactions, based on alkoxysilane compounds, which have improved cosmetic properties.

There is also a need to provide compositions using these sol/gel reactions, based on alkoxysilane compounds, which have improved mechanical properties, especially in terms of scratch resistance.

Thus, the preparation of a cosmetic or dermatological composition for rapidly forming a coating on keratin materials is targeted.

Rapid drying and excellent wear of the said coating are also sought. Specifically, the layer of the composition deposited on the keratin materials may, if the reaction takes place slowly and if it does not dry quickly, prove to be tacky after its application and/or to be degraded on contact with foreign bodies with which it may come into contact, for instance a glass, a cigarette, an item of clothing or the skin, which will be an inconvenience to users.

Remanence properties on washing with water and with detergents are finally sought, as is stability of the film obtained. The inventors have indeed found that such advantages can be achieved by using a combination of particular alkoxysilanes, combined with specific pH conditions for the final composition.

Another advantage imparted by such a coating is that it in particular has improved hardness.

Thus, a subject of the present invention is a cosmetic or dermatological composition of sol/gel type for making up and/or caring for keratin materials, and/or for making up the teeth, characterized in that it is obtained by mixing:

(a) at least one alkylalkoxysilane of formula R¹ _xSi(OR²)(4__x) or

[R¹ _ySiO(4-_y)/₂]n[R¹ _X(OR²)_zSiO(4-_X-z)/2]m;

(b) at least one alkoxysilane monomer or oligomer of formula R³ _xSi(OR²)(4__x) or [R³ _ySiO(4-_y)/₂]n[R³ _x(OR²)_zSiO(4 -x-z)/₂]m₅

(c) at least one acid, in an amount sufficient for the said cosmetic or dermatological composition to have a pH of between 3 and 6 and preferably between 3.5 and 5; and (d) an amount of water sufficient to enable hydrolysis of the sol/gel reaction.

According to the present invention, the radical R¹ of the said alkylalkoxysilane represents, independently, a linear or branched, saturated or unsaturated Ci-C₂o alkyl group, or a phenyl group,

R² represents, independently, a linear or branched, saturated or unsaturated Ci-Cio alkyl group, and for the said alkylalkoxysilane,

x represents, independently, 0, 1 or 2,

y represents, independently, 0, 1 , 2 or 3,

z represents, independently, 1 , 2 or 3,

the sum of x and z is less than or equal to 3.

Finally, n and m are integers whose sum is less than 50.

According to the present invention, the radical R³ of the said alkoxysilane monomer or oligomer represents, independently, a nucleophilic group other than a silanol, or a linear or branched, saturated or unsaturated Ci-C₂o alkyl group, optionally substituted with at least one nucleophilic group other than a silanol. Furthermore, at least one of the groups R³ of the said monomer or oligomer is a nucleophilic group other than a silanol or a linear or branched, saturated or unsaturated C1-C20 alkyl group, substituted with at least one nucleophilic group.

Concerning said alkoxysilane, R², z, and n + m are as defined previously.

Moreover, when said alkoxysilane is of formula R³ _xSi(OR²)(4-_x), x represents 1 or 2 and when it is of formula [R³ _ySiO(4-y)/2]n[R³x(OR²)_zSiO(4-_x-_z)/2]m, x and y are as defined previously for the said alkylalkoxysilane, with at least x or y being different from 0.

These compounds are capable of reacting together on keratin materials, on the teeth or on a support, so as rapidly to form on the said keratin materials, teeth or support a coating film in accordance with the invention.

Thus, the time for formation of the coating film may be improved relative to a composition not comprising the combination of alkoxysilanes under the pH conditions in accordance with the invention, and makes it possible to form an adherent film that shows improved wear, hardness and/or stability.

The films obtained in the context of the present invention moreover show good gloss properties.

In particular, it has been demonstrated by the inventors that the pH as defined above, combined with the composition per se, makes it possible to appreciably improve the stability of the composition.

The inventors have also demonstrated the fact that the alkoxysilane monomer or oligomer comprising at least one nucleophilic group, as defined above, makes it possible to significantly increase the rate of the sol/gel reaction, thus making it possible to reduce the sol/gel reaction time following the application of the said composition, and also its drying time.

The present invention also relates to a kit for coating keratin materials and/or the teeth, comprising at least two different compositions packaged separately, the said kit comprising components (a) to (d) as defined above.

The present invention also relates to a cosmetic process for coating keratin materials and/or the teeth, which consists in applying to the said keratin materials and/or the teeth at least one coat of a mixture of at least two different compositions, compounds (a) to (d) as defined previously being included in the said at least two different compositions, the said mixture of the at least two different compositions having a pH in accordance with the invention.

According to a first variant, the said mixture of the at least two different compositions is obtained extemporaneously before application to the keratin materials and/or to the teeth.

According to a second embodiment, the said mixture of the at least two different compositions is obtained simultaneously with its application to the keratin materials and/or to the teeth.

The composition according to the invention has the advantage of allowing the production of a coating film to be applied to keratin materials and/or to the teeth, and more particularly the nails, after a rapid reaction time and also a rapid drying time.

The coating film thus obtained also shows improved wear and good gloss.

This film also has improved hardness and stability.

According to the invention, the term "keratin material" means not only the hair, the eyelashes, the eyebrows, bodily hair and the nails, but also the skin.

The "hardness" of the coating film is measured according to standard ASTM D-43-66 or standard NF-T 30-016 (December 1991), using a Persoz pendulum.

The "stability" of the composition refers to a composition that remains sufficiently fluid over time to be applied to the nails, especially after 1 week at 20°C.

The "gloss" of the coating film is measured at 20°C and at 60°C using a Byk- Gardner brand glossmeter of microTri-Gloss reference.

Mixture of alkoxysilanes

The present invention uses a hazard- free reactive chemical family that reacts via a well-known sol/gel route: alkoxysilane monomers or oligomers.

Compounds (a) and (b) as presented above are different. According to the present invention, the alkylalkoxysilane (a) in accordance with the invention is defined by the formula R¹ _xSi(OR²)(4__x) or [R¹ _ySiO(4-_y)/2]n[R¹x(OR²)_zSiO(4-_x- z)/₂]_m in which:

R¹ represents, independently, a linear or branched, saturated or unsaturated C1-C20 alkyl group, or a phenyl group,

R² represents, independently, a linear or branched, saturated or unsaturated C1-C10 alkyl group,

x represents, independently, 0, 1 or 2,

y represents, independently, 0, 1, 2 or 3,

z represents, independently, 1, 2 or 3,

the sum of x and z is less than or equal to 3,

and n and m are integers whose sum is less than 50.

According to one embodiment variant, R¹ may represent, independently, a linear or branched, saturated or unsaturated C1-C10 and preferably C1-C5 alkyl group.

According to one preferred embodiment, R¹ represents, independently, a methyl, ethyl or propyl group, preferably a methyl.

According to another preferred embodiment, R¹ represents a phenyl group. According to one embodiment variant, R² may represent, independently, a linear or branched, saturated or unsaturated C1-C5 alkyl group.

According to one preferred embodiment, R² represents, independently, a methyl or ethyl group, preferably an ethyl.

According to another preferred embodiment, the sum of n and m is less than 30 and preferably less than 20.

According to one preferred embodiment, x is 1.

According to one preferred embodiment, the alkylalkoxysilane is of formula

The alkylalkoxysilane compound may be chosen especially from methyltriethoxysilane (MTES), dimethyldiethoxysilane, tetraethoxysilane, ethyltriethoxysilane, diethyldiethoxysilane, propyltriethoxysilane and dipropyldiethoxysilane.

Preferentially, the alkylalkoxysilane compound according to the invention is

MTES. This compound may be sold, for example, by Evonik under the name Dynasylan MTES.

The alkylalkoxysilane compound may be present in the composition according to the invention in a concentration of between 20% and 90% by weight relative to the total weight of the composition.

Preferably, this compound is present in a concentration of between 25% and 40% by weight, relative to the total weight of the composition.

According to the present invention, the alkoxysilane monomer or oligomer (b)

3 2 3 3 2

is defined by the formula R _xSi(OR )(_4-x) or [R _ySiO(4-_y)/2]n[R x(OR )_zSiO(_4-x-zy₂]_m in which: R³ represents, independently, a nucleophilic group other than a silanol, or a linear or branched, saturated or unsaturated C1-C20 alkyl group, optionally substituted with at least one nucleophilic group other than a silanol.

Furthermore, at least one of the groups R³ of the said monomer or oligomer is a nucleophilic group other than a silanol, or a linear or branched, saturated or unsaturated C1-C20 alkyl group, substituted with at least one nucleophilic group.

R², z, and n + m are as defined previously.

When (b) is of formula R³ _xSi(OR²)(4-_x), x represents 1 or 2.

When (b) is of formula [R³ _ySiO(4-_y)/2]n[R³ _x(OR²)_zSiO(4-_x-z)/₂] _m, x and y are as defined previously for (a), with at least x or y being different from 0.

According to one preferred embodiment, at least one of the groups R³ represents a nucleophilic group chosen from an amine or thiol group, or a linear or branched, saturated or unsaturated C1-C20 alkyl group, substituted with at least one nucleophilic group chosen from an amine or thiol group, preferably an amine.

The said linear or branched, saturated or unsaturated alkyl group is preferably of C1-C10, preferably of Ci-Cs and preferentially of C1-C4.

Preferably, at least one of the groups R³ represents an aminopropyl group. According to a preferred embodiment, R² is as defined according to one of the preferred embodiments mentioned previously.

According to one preferred embodiment, x is 1.

According to another preferred embodiment, the sum of n and m is less than 30 and preferably less than 20. According to another preferred embodiment, the alkoxysilane comprising at least one nucleophilic group is of formula R³ _xSi(OR²)(4__x).

The alkoxysilane compound comprising at least one nucleophilic group may be chosen especially from 3-aminopropyltriethoxysilane (APTES),

3-aminopropylmethyldiethoxysilane (APMDES) and oligomers formed from APTES or APMDES.

APTES may be sold, for example, by the company Dow Corning under the name Xiameter OFS-6011 Silane.

APMDES may be sold, for example, by the company Evonik under the name

Dynasylan 1505.

Preferentially, the alkoxysilane compound comprising at least one nucleophilic group is 3-aminopropyltriethoxysilane (APTES).

The alkoxysilane compound comprising at least one nucleophilic group may be present in the composition according to the invention in a concentration of between 0.5% and 5% by weight relative to the total weight of the composition.

Preferably, this compound is present in a concentration of between 0.5% and 2% by weight, relative to the weight of the composition. The alkylalkoxysilane and alkoxysilane compounds comprising at least one nucleophilic group may be present in a composition in accordance with the invention in a ratio of between 100 and 10, preferentially from 70 to 15 and even more particularly from 40 to 20.

The ratio between these two compounds may vary so as to modify the rate of reaction and thus the rate of formation of the film, or alternatively so as to adapt the properties of the formed film according to the desired application.

Acid

A composition according to the present invention also comprises at least one acid.

This acid may be chosen from lactic acid, acetic acid, citric acid, tartaric acid, hydrochloric acid, sulfuric acid and phosphoric acid. This acid is preferably lactic acid.

The acid present in the composition according to the invention must be present in an amount sufficient for the said composition to have a pH of between 3 and 6.

Preferably, the pH of the composition may be between 3.5 and 5.

More preferentially, the pH of the composition may be between 3.8 and 4.3.

Lactic acid may especially be present in the composition in a content of between 5% and 10% by weight and preferably in a content of between 6% and 10% by weight relative to the total weight of the composition. Water

A composition according to the invention furthermore comprises an amount of water sufficient to enable hydrolysis of the sol/gel reaction.

According to one preferred embodiment, the composition comprises at least 15% by weight of water relative to the total weight of the composition.

Preferentially, the composition comprises at least 18% by weight of water and preferably at least 20% by weight of water relative to the total weight of the composition.

According to one embodiment, the alkylalkoxysilane (a) is methyltriethoxysilane (MTES) and the alkoxysilane (b) comprising at least one nucleophilic group is 3-aminopropyltriethoxysilane (APTES), in a ratio (a)/(b) of between 20 and 40, this ratio preferably being equal to 30.

According to another particular embodiment, the invention relates to a composition comprising:

(a) methyltriethoxysilane (MTES),

(b) 3-aminopropyltriethoxysilane (APTES),

(c) lactic acid in an amount sufficient for the composition to have a final pH in accordance with the invention, for example in a content of between 5% and 10% by weight and preferably in a content of between 6% and 10% by weight relative to the total weight of the composition, and

(d) water in an amount sufficient for the sol/gel reaction to take place, for example in a content of greater than 20% by weight relative to the total weight of the composition, (e) and also optionally ethanol.

A composition according to the invention is liquid, due to its pH conditions indicated previously and to the presence of water.

According to the invention, a "liquid composition" means a composition having a particular viscosity at ambient temperature (i.e. 20°C).

More precisely, a liquid composition presents, at 20°C, a viscosity varying between 0,0001 and 25 Pa/s, preferably between 0,001 and 5 Pa/s, et more preferably between 0,01 and 1 Pa/s.

The viscosity measurement is performed at 20° C, using a Rheomat RM 180 viscometer equipped with a No. 4 spindle, the measurement being performed after rotation of the spindle in the composition for 10 minutes (after which time stabilization of the viscosity and of the rotation speed of the spindle were observed), at a shear rate of 200 s^"1.

Additional compounds

The composition according to the invention may also comprise an additional alkoxysilane monomer or oligomer other than the preceding compounds.

This additional compound may be chosen from dimethyldiethoxysilane (DMDES), diethyldiethoxysilane and dipropyldiethoxysilane, preferably DMDES.

A composition according to the invention may also comprise at least one alcohol chosen from ethanol, isopropanol, butanol, 2-butanol, methyl- 1-propanol and methyl-2-propanol, preferably ethanol.

Such an alcohol may be present in the composition in a concentration of greater than 10% by weight relative to the total weight of the composition.

Preferably, the alcohol is present in the composition at a concentration of greater than 20% by weight, preferably greater than 30% by weight and preferentially greater than 35% by weight relative to the total weight of the composition.

A composition according to the invention may also comprise at least one glycol chosen from glycerol, propylene glycol, butylene glycol and pentylene glycol, preferably glycerol. Such a glycol may be present in the composition in a concentration of less than 10% by weight and preferably less than 5% by weight relative to the total weight of the composition. A composition according to the invention may also comprise ingredients commonly used in cosmetics and more especially in the field of nail cosmetics and/or nailcare.

They may be chosen especially from film-forming polymers, film-forming agents, pigments, nacres and dyes.

For the purposes of the present invention, the term "film-forming polymer" denotes a polymer that is capable, by itself or in the presence of an auxiliary film-forming agent, of forming an isolable and especially continuous and adherent film, on a support, especially on the nails.

A single additional film- forming polymer or a mixture of additional film- forming polymers may be used in the composition.

This additional film-forming polymer may be chosen from the group formed by synthetic polymers of radical type or of polycondensate type, and polymers of natural origin, and mixtures thereof.

A film- forming polymer that is suitable for use in the invention may be chosen in particular from:

- polysaccharides. Among the polysaccharides that are suitable for use in the invention, examples that may be mentioned include cellulose esters and ethers, such as nitrocellulose, cellulose acetate, cellulose acetobutyrate, cellulose acetopropionate and ethylcellulose, or alternatively optionally modified guar gum, such as ethylguar.

- synthetic polymers such as polyurethanes, acrylic polymers, vinyl polymers, polyvinyl butyrals, alkyd resins and ketone/aldehyde resins, resins derived from aldehyde condensation products, such as arylsulfonamide-formaldehyde resins, for instance toluenesulfonamide-formaldehyde resin, arylsulfonamide-epoxy resins or ethyl tosylamide resins;

- polymers of natural origin, such as plant resins, such as dammar resins, elemi gums, copal resins, and benzoin; gums such as shellac, sandarac gum and gum mastic. Use may in particular be made, as additional film-forming polymers, of the toluenesulfonamide/formaldehyde resins Ketjentflex MS80 from Akzo or Santolite MHP or Santolite MS 80 from Faconnier or Resimpol 80 from Pan Americana, the alkyd resin Beckosol ODE 230-70-E from Dainippon, the acrylic resin Acryloid B66 from Rohm & Haas, the polyurethane resin Trixene PR 4127 from Baxenden or the acetophenone/formaldehyde resin sold under the reference Synthetic Resin SK by Degussa.

According to one particular embodiment, the additional film-forming polymer is chosen from polysaccharides or polysaccharide derivatives, preferably from cellulose ethers and esters.

For example, the content of film- forming polymer may range from 0.1% to 30% by weight, especially from 0.5%> to 20%> by weight and in particular from 1% to 10%> by weight relative to the total weight of the composition. The auxiliary film- forming agent may be chosen from any compound known to those skilled in the art as being capable of satisfying the desired function, and may be chosen especially from plasticizers and coalescers for the film- forming polymer.

In particular, mention may be made, alone or as mixtures, of common plasticizers or coalescers such as:

- glycol derivatives such as diethylene glycol ethyl ether, diethylene glycol methyl ether, diethylene glycol butyl ether or diethylene glycol hexyl ether, ethylene glycol ethyl ether, ethylene glycol butyl ether and ethylene glycol hexyl ether,

- glycol esters,

- propylene glycol derivatives and in particular propylene glycol phenyl ether, propylene glycol diacetate, dipropylene glycol butyl ether, tripropylene glycol butyl ether, propylene glycol methyl ether, dipropylene glycol ethyl ether, tripropylene glycol methyl ether, diethylene glycol methyl ether and propylene glycol butyl ether,

- acid esters, especially carboxylic acid esters, such as citrates, especially triethyl citrate, tributyl citrate, triethyl acetyl citrate, tributyl acetyl citrate and tris(2- ethylhexyl) acetyl citrate; phthalates, especially diethyl phthalate, dibutyl phthalate, dioctyl phthalate, dipentyl phthalate and dimethoxyethyl phthalate; phosphates, especially tricresyl phosphate, tributyl phosphate, triphenyl phosphate and tributoxyethyl phosphate; tartrates, especially dibutyl tartrate; adipates; carbonates; sebacates; benzyl benzoate, butyl acetylricinoleate, glyceryl acetylricinoleate, butyl glycolate, camphor, glyceryl triacetate and N-ethyl-o,p-toluenesulfonamide,

- oxyethylenated derivatives such as oxyethylenated oils, especially plant oils such as castor oil; silicone oils, and

- mixtures thereof.

The type and amount of plasticizer and/or coalescer may be chosen by a person skilled in the art on the basis of his general knowledge.

For example, the plasticizer and/or coalescer content may range from 0.01% to 10% and in particular from 1% to 5% by weight relative to the total weight of the composition.

A composition according to the invention may also comprise at least one organic or mineral dyestuff, especially such as the pigments or nacres conventionally used in cosmetic compositions.

The term "pigments" should be understood as meaning white or coloured, mineral or organic particles that are insoluble in an aqueous solution, which are intended to colour and/or opacify the resulting film.

The pigments may be present in a proportion of from 0.01% to 15% by weight, especially from 0.01% to 10% by weight and in particular from 0.02% to 5% by weight relative to the total weight of the composition. As mineral pigments that may be used in the invention, mention may be made of titanium oxide, zirconium oxide or cerium oxide, and also zinc oxide, iron oxide or chromium oxide, ferric blue, manganese violet, ultramarine blue and chromium hydrate.

They may also be pigments having a structure that may be, for example, of sericite/brown iron oxide/titanium dioxide/silica type. Such a pigment is sold, for example, under the reference Coverleaf NS or JS by the company Chemicals and Catalysts, and has a contrast ratio in the region of 30.

The dyestuff may also comprise a pigment with a structure that may be, for example, of silica microsphere type containing iron oxide. An example of a pigment having this structure is the product sold by the company Miyoshi under the reference PC Ball PC-LL-100 P, this pigment consisting of silica microspheres containing yellow iron oxide.

Among the organic pigments that may be used in the invention, mention may be made of carbon black, pigments of D&C type, lakes based on cochineal carmine or on barium, strontium, calcium or aluminium, or alternatively the diketopyrrolopyrroles (DPP) described in documents EP-A-542669, EP-A-787730, EP-A-787731 and WO-A-96/08537.

The term "nacres" should be understood as meaning iridescent or non- iridescent coloured particles of any shape, especially produced by certain molluscs in their shell or alternatively synthesized, which have a colour effect via optical interference.

The nacres may be chosen from nacreous pigments such as titanium mica coated with an iron oxide, mica coated with bismuth oxychloride, titanium mica coated with chromium oxide, titanium mica coated with an organic dye and also nacreous pigments based on bismuth oxychloride. They may also be mica particles at the surface of which are superposed at least two successive layers of metal oxides and/or of organic dyestuffs.

Examples of nacres that may also be mentioned include natural mica coated with titanium oxide, with iron oxide, with natural pigment or with bismuth oxychloride.

Among the nacres available on the market, mention may be made of the nacres Timica, Flamenco and Duochrome (based on mica) sold by the company Engelhard, the Timiron nacres sold by the company Merck, the Prestige mica-based nacres, sold by the company Eckart, and the Sunshine synthetic mica-based nacres, sold by the company Sun Chemical.

The nacres may more particularly have a yellow, pink, red, bronze, orange, brown, gold and/or coppery color or tint.

As illustrations of nacres that may be used in the context of the present invention, mention may be made especially of the gold-coloured nacres sold especially by the company Engelhard under the name Brilliant gold 212G (Timica), Gold 222C (Cloisonne), Sparkle gold (Timica), Gold 4504 (Chromalite) and Monarch gold 233X (Cloisonne); the bronze nacres sold especially by the company Merck under the name Bronze fine (17384) (Colorona) and Bronze (17353) (Colorona) and by the company Engelhard under the name Super bronze (Cloisonne); the orange nacres sold especially by the company Engelhard under the name Orange 363C (Cloisonne) and Orange MCR 101 (Cosmica) and by the company Merck under the name Passion orange (Colorona) and Matte orange (17449) (Microna); the brown nacres sold especially by the company Engelhard under the name Nu-antique copper 340XB (Cloisonne) and Brown CL4509 (Chromalite); the nacres with a copper tint sold especially by the company Engelhard under the name Copper 340A (Timica); the nacres with a red tint sold especially by the company Merck under the name Sienna fine (17386) (Colorona); the nacres with a yellow tint sold especially by the company Engelhard under the name Yellow (4502) (Chromalite); the red nacres with a gold tint sold especially by the company Engelhard under the name Sunstone GO 12 (Gemtone); the pink nacres sold especially by the company Engelhard under the name Tan opale G005 (Gemtone); the black nacres with a gold tint sold especially by the company Engelhard under the name Nu antique bronze 240 AB (Timica), the blue nacres sold especially by the company Merck under the name Matte blue (17433) (Microna), the white nacres with a silvery tint sold especially by the company Merck under the name Xirona Silver, and the golden-green pink-orange nacres sold especially by the company Merck under the name Indian summer (Xirona), and mixtures thereof.

A composition according to the invention may also comprise water-soluble or liposoluble dyes in a content ranging from 0.01% to 10% by weight and especially ranging from 0.01% to 5% by weight relative to the total weight of the composition.

The liposoluble dyes are, for example, Sudan Red, DC Red 17, DC Green 6, β-carotene, soybean oil, Sudan Brown, DC Yellow 11 , DC Violet 2, DC Orange 5 and quinoline yellow. The water-soluble dyes are, for example, beetroot juice or methylene blue.

It may also contain one or more formulation additives commonly used in cosmetics and more especially in the field of nail cosmetics. They may be chosen especially from vitamins, trace elements, softeners, sequestrants, wetting agents, thickeners, dispersants, antifoams, spreading agents, co-resins, film-forming polymers, plasticizers, fillers, coalescers, preserving agents, UV-screening agents, active agents, moisturizers, neutralizers, stabilizers and antioxidants, and mixtures thereof.

A composition in accordance with the invention more particularly intended for making up and/or caring for the nails may especially comprise, as active agents, keratin material hardeners, active agents that act on nail growth, for instance methylsulfonylmethane, and/or active agents for treating various conditions located on the nail, for instance onychomycosis.

The amounts of these various ingredients are those conventionally used in this field, for example from 0.01% to 20% by weight and especially from 0.02% to 10% by weight relative to the total weight of the composition in accordance with the invention.

A composition according to the invention may be in the form of an aqueous, organic or aqueous-organic solution or suspension, an oil-in- water, water-in-oil or multiple emulsion, especially a cream or a milk; an aqueous or oily gel, a dispersion, a spray composition or a patch.

As previously indicated, a composition according to the invention is liquid at ambient temperature and can thus be applied by means of an applicator, as for example a finger or a brush, or other applicators well known to the man skilled in the art.

Accordingly, the different additional compounds indicated previously that can be present in a composition according to the invention must be in a quantity that does not alter this liquid state.

Moreover, it can be noted that a composition according to the invention, liquid/fluid before its application, changes after its application in situ in order to become solid or in a gel state, due to the sol-gel reaction.

The compositions in accordance with the invention may be applied to the teeth.

A composition according to the invention may thus be in the form of a makeup composition such as a nail varnish, a varnish base, a nailcare product, a liquid lipstick, a foundation, a haircare composition such as a styling lacquer or lotion, or a styling spray.

It is more preferentially a nail varnish, the said nail varnish possibly being transparent or coloured.

A composition according to the invention comprises a physiologically acceptable medium. The term "physiologically acceptable medium" means a non-toxic medium that may be applied to human keratin materials and/or human teeth and that has a pleasant appearance, odour and feel.

Coating kit

The present invention also relates to a kit for coating keratin materials and/or the teeth, comprising at least two different compositions conditioned separately, the said kit comprising components (a) to (d) as defined above.

According to one embodiment, the alkylalkoxysilane and the alkoxysilane comprising at least one nucleophilic group are conditioned in the same composition.

According to a second embodiment, the alkylalkoxysilane and the alkoxysilane comprising at least one nucleophilic group are conditioned in at least two different compositions.

According to this second embodiment, the said at least two different compositions may be combined just before or during application.

According to the present invention, the mixing obtained after combining the at least two different compositions takes place at a pH in accordance with the invention.

The alkylalkoxysilane and alkoxysilane compounds comprising at least one nucleophilic group may be present, respectively, in the kit according to the invention, in a first composition and/or in a second composition, or even in a composition other than the said first and second compositions.

According to one embodiment, compound (a) optionally with at least one of the compounds (c) or (d) is present in a first composition of the kit according to the invention and compound (b) optionally with at least one of the compounds (c) or (d) is present in a second composition of the kit according to the invention.

The said first and/or second different compositions of the kit according to the invention may also comprise at least one additional compound as defined previously.

According to one embodiment, the first composition of the kit according to the invention, as defined previously, may also comprise at least one additional compound and/or the second composition of the kit according to the invention, as defined previously, may also comprise at least one such additional compound, which is identical to or different from that or those optionally present in the first composition.

Each composition of the kit may be conditioned separately in the same conditioning article.

According to one particular embodiment, each composition of the kit according to the invention may be conditioned in a two-compartment pen, the first composition being delivered from one end of the pen and the second composition being delivered from the other end of the pen, each end being, for example, closed in a leaktight manner by a cap.

Each composition may also be conditioned in a separate compartment within the same conditioning article, the mixing of the at least two compositions taking place at the end(s) of the conditioning article during the delivery of the composition. The conditioning article(s) may be water-tight and/or airtight.

Alternatively, each composition may be conditioned in a different conditioning article.

Moreover, each composition is liquid before its application. The change of state after application indicated previously only occurs after application, on the same site, of all the compounds (a) to (d).

It remains that the composition obtained by mixing all of the various compositions of the kit according to the invention, in situ or extemporaneously, has a final pH as defined previously, namely of between 3 and 6, preferably between 3.5 and 5 and preferably between 3.8 and 4.3.

Coating process

According to the embodiment relating to the single composition, the present invention relates to a cosmetic process for coating keratin materials and/or the teeth, which consists in applying to the said keratin materials and/or the teeth at least one coat of a composition in accordance with the invention. According to the embodiment in kit form, the present invention also relates to a cosmetic process for coating keratin materials and/or the teeth, which consists in applying to the said keratin materials and/or the teeth at least one coat of a mixture of at least two different compositions as defined above.

Preferably, the pH obtained after mixing the at least two different compositions indicated above is between 3.8 and 4.3.

According to one embodiment, the coating process according to the invention consists in extemporaneously mixing the said at least two different compositions comprising compounds (a) to (d) and optionally an additional alkoxysilane monomer or oligomer, an alcohol and/or a cosmetic or dermatological active agent as defined previously, and in applying to the said keratin materials and/or the teeth at least one coat of the said mixture obtained.

According to another embodiment, the coating process according to the invention consists in applying to the keratin materials and/or the teeth at least one coat of a first composition and at least one coat of a second composition, the said first and second compositions being different and together comprising compounds (a) to (d) as defined previously, and optionally an additional alkoxysilane monomer or oligomer, and an alcohol and/or a cosmetic or dermatological active agent as defined previously.

The order of application of the said first and second different compositions is irrelevant.

It is also possible to apply alternately to the keratin materials and/or the teeth several coats of each of the said first and second different compositions.

According to another particular embodiment, at least one additional coat of at least one composition comprising an additional alkoxysilane monomer or oligomer, and an alcohol and/or a cosmetic or dermatological active agent as defined previously, may be applied to the keratin materials and/or to the teeth.

Such an additional coat may be applied, without preference, before or after the application of the mixture of the at least two different compositions, or before, between or after the application of the coats of each of the said first and second different compositions, to the keratin materials and/or to the teeth.

Needless to say, each composition comprises a physiologically acceptable medium, i.e. a non-toxic medium that may be applied to human keratin materials and/or human teeth and that has a pleasant appearance, odour and feel.

According to one preferred embodiment, the said keratin materials more particularly concern the nails. According to one embodiment, the composition(s) and the mixture according to the invention may be applied to the keratin materials, and more particularly the nails, and/or the teeth using a brush, or even several brushes in the case of the kit.

According to another embodiment, the composition(s) and the mixture according to the invention may be applied to the keratin materials, and more particularly the nails, and/or the teeth using a felt -tip pen, or even several felt-tip pens in the case of the kit. Such pens are described, for example, in patent FR 2 909 844.

According to one particular embodiment, the said coating process is performed with application of heat.

This application of heat, when the composition is a liquid lipstick, may be, for example, a means not specifically intended for heating, such as a hot body (hot cup or drink).

The composition may also be heated using a means specifically dedicated to heating, for instance a means for propelling hot air such as a hair dryer or a drying device, for instance a heating applicator.

The examples given below are presented as non-limiting illustrations of the invention. EXAMPLES

Example 1

The solution remains fluid after one week at 20°C.

After application to its support and drying, this composition forms smooth, glossy film after a few minutes.

Example 2

The composition of Example 2 has a pH of 4.2.

The solution remains fluid after one week at 20°C.

After application to a support and drying, this composition also forms a hard, smooth, glossy film after a few minutes. Example 3 - Comparative example not comprising an alkoxysilane containing a nucleophilic group

The solution remains fluid after one week at 20°C.

The composition of Example 3 has a lower reaction rate than the composition of Example 1. Specifically, the film formed from the composition of Example 3 is still tacky after one hour.

Example 4 - Comparative example with a pH of greater than 6

The composition is gelled after one week.

Protocol for preparing the composition according to Example 1:

1. Preparation of the composition containing 70% MTES

With magnetic stirring, the water and the lactic acid are mixed together and the MTES is gradually added thereto until a clear homogeneous phase is obtained. 2. Preparation of the composition containing 50% APTES

With magnetic stirring, the water and the APTES are mixed together until a clear homogeneous phase is obtained.

3. Preparation of the final composition

With magnetic stirring, the water, the ethanol and the lactic acid are mixed together, and the MTES composition and then the APTES composition are incorporated

The final solution is clear and homogeneous.

Claims

1. Cosmetic or dermatological composition of sol/gel type for making up and/or caring for keratin materials, and/or for making up the teeth, characterized in that it is obtained by mixing:

(a) at least one alkylalkoxysilane of formula R¹ _xSi(OR²)(4__x) or [R¹ _ySiO(4-_y)/2]n[R¹ _x(OR²)_zSiO(4-_x-z)/2]m in which:

x represents, independently, 0, 1 or 2,

y represents, independently, 0, 1, 2 or 3,

z represents, independently, 1, 2 or 3,

the sum of x and z is less than or equal to 3,

and n and m are integers whose sum is less than 50,

(b) at least one alkoxysilane monomer or oligomer of formula R³ _xSi(OR²)(4__x) or [R³ _ySiO(4-_y)/2]n[R³ _x(OR²)_zSiO(4-_x-z)/2]m in which:

R³ represents, independently, a nucleophilic group other than a silanol, or a linear or branched, saturated or unsaturated C1-C20 alkyl group, optionally substituted with at least one nucleophilic group other than a silanol,

at least one of the groups R³ of the said monomer or oligomer is a nucleophilic group other than a silanol, or a linear or branched, saturated or unsaturated C1-C20 alkyl group, substituted with at least one nucleophilic group,

R², z, and n + m are as defined previously,

and when said alkoxysilane is of formula R³ _xSi(OR²)(4__x), x represents 1 or 2, and when said alkoxysilane is of formula [R³ _ySiO(4-_y)/2]n[R³ _x(OR²)_zSiO(4-_x-_z)/2]m, x and y are as defined previously for said alkylalkoxysilane with at least x or y being different from 0,

(c) at least one acid, in an amount sufficient for the said cosmetic or dermatological composition to have a pH of between 3 and 6, and

(d) an amount of water sufficient to enable hydrolysis of the sol/gel reaction.

2. Composition according to Claim 1 , characterized in that the alkylalkoxysilane is chosen from methyltriethoxysilane (MTES), dimethyldiethoxysilane, tetraethoxysilane, ethyltriethoxysilane, diethyldiethoxysilane, propyltriethoxysilane and dipropyldiethoxysilane, and is more preferentially MTES.

3. Composition according to either of Claims 1 and 2, characterized in that at least one of the groups R³ of the said alkoxysilane monomer or oligomer represents an amine or thiol group, preferably an aminopropyl group, or a linear or branched, saturated or unsaturated C1-C20 alkyl group, substituted with at least one amine or thiol group, preferably and aminopropyl group.

4. Composition according to any one of the preceding claims, characterized in that the alkoxysilane comprising at least one nucleophilic group is chosen from 3-aminopropyltriethoxysilane (APTES), 3-aminopropylmethyldiethoxysilane (APMDES) and oligomers formed from 3-aminopropyltriethoxysilane or 3-aminopropylmethyldiethoxysilane, the said alkoxysilane comprising at least one nucleophilic group preferably being APTES.

5. Composition according to any one of the preceding claims, characterized in that the pH of the said composition is between 3.5 and 5 and preferably between 3.8 and 4.3, the said acid preferably being lactic acid.

6. Composition according to any one of the preceding claims, characterized in that the said compounds (a) and (b) are present in the composition in a concentration, respectively, of between 20% and 90%> by weight, preferably between 25% and 40%> by weight, and between 0.5%> and 5% and preferably between 0.5%> and 2% by weight relative to the total weight of the composition.

7. Composition according to any one of the preceding claims, characterized in that the ratio between compounds (a) and (b) is between 100 and 10, preferentially from 70 to 15 and even more particularly from 40 to 20.

8. Composition according to any one of the preceding claims, characterized in that it comprises at least 15% by weight of water, preferably at least 18% by weight of water and preferably at least 20% by weight of water relative to the total weight of the composition.

9. Composition according to any one of the preceding claims, characterized in that it also comprises at least one alcohol, preferably ethanol, introduced into the composition to a concentration of greater than 10% by weight, preferably greater than 20% by weight, preferably greater than 30% by weight and preferentially greater than 35% by weight relative to the total weight of the composition.

10. Composition according to any one of the preceding claims, characterized in that it also comprises a third alkoxysilane monomer or oligomer, different from (a) and (b), chosen from dimethyldiethoxysilane (DMDES), diethyldiethoxysilane and dipropyldiethoxysilane, preferably dimethyldiethoxysilane (DMDES).

11. Composition according to any one of the preceding claims, characterized in that it also comprises at least one cosmetic or dermatological active agent chosen from film- forming polymers, film- forming agents, pigments, nacres, dyes, vitamins, trace elements, softeners, sequestrants, wetting agents, thickeners, dispersants, antifoams, spreading agents, co-resins, plasticizers, fillers, coalescers, preserving agents, UV-screening agents, active agents, moisturizers, neutralizers, stabilizers and antioxidants, and mixtures thereof.

12. Composition according to any one of the preceding claims, characterized in that it is a nail varnish, a nail base, a nailcare product, a liquid lipstick, a foundation, a haircare composition such as a styling lacquer or lotion, or a styling spray, preferentially a nail varnish.

13. Kit for coating keratin materials and/or the teeth, comprising at least two different compositions packaged separately, the said kit comprising components (a) to (d) as defined according to any one of the preceding claims,

the mixture obtained after combining the at least two different compositions having a pH as defined in Claim 1 or 5.

14. Cosmetic process for coating keratin materials and/or the teeth, which consists in applying to the said keratin materials and/or the teeth at least one coat of a mixture of at least two different compositions, compounds (a) to (d) as defined in any one of Claims 1 to 4 being included in the said at least two different compositions,

the said mixture of the at least two different compositions having a pH as defined in Claim 1 or 5.

15. Process according to the preceding claim, characterized in that it is performed with application of heat.