According to one variant, a subject of the invention is a process for making up and/or caring for the nails, which consists in: a) applying to the nail at least one coat of a first composition comprising at least one n- octyl 2-cyanoacrylate monomer, b) and then applying onto the said coat at least one coat of a second composition.

The terms "first composition" and "second composition" do not in any way condition the order of application of the said compositions to the nails. The second composition may be applied onto the first composition, and vice versa. According to another variant, a subject of the invention is also a process for making up and/or caring for the nails, which consists in: a) extemporaneously mixing: at least one first composition comprising at least one cyanoacrylate monomer of formula (I)

in which R represents an alkyl or alkoxyalkyl radical, and at least one second composition, and then b) applying to the nail at least one coat of the said mixture.

According to one embodiment, at least one additional coat of at least one third liquid composition, such as a conventional nail varnish, comprising a film-forming polymer and an organic or aqueous solvent medium, is applied onto the coat of second composition in order, for example, to improve the staying power and/or gloss thereof.

According to another aspect, a subject of the present invention is also a kit for making up or caring for the nails, comprising: i) a first composition comprising at least one cyanoacrylate monomer of formula (I)

in which R represents an alkyl or alkoxyalkyl radical, ii) a second composition.

Preferably, the makeup kit according to the invention comprises the first and second compositions in separate packaging .

A subject of the invention is also the use of a kit as described above, for obtaining a film deposited on the nails, which shows improved staying-power and/or wear- resistance properties.

The film of varnish also shows significant staying power over time, especially at a scale of at least five days and preferably one week. It thus proves to be resistant to water, to rubbing and to impacts, and does not show any significant wear or chipping within this period.

Cyanoaerylate monomer

The cyanoaerylate monomer of the first composition used in the process according to the invention has the following formula:

in which R represents an alkyl or alkoxyalkyl radical.

In the context of the invention, the alkyl or alkoxyalkyl radicals may be linear, branched or cyclic.

Cyanoaerylate monomers of formula (I) that may be mentioned include electrophilic monomers, for instance ethyl 2-cyanoacrylate, methyl 2-cyanoacrylate, n-propyl 2-cyanoacrylate, isopropyl 2-cyanoacrylate, tert-butyl 2-cyanoacrylate, n-butyl 2-cyanoacrylate, isobutyl 2- cyanoacrylate, 3-methoxybutyl cyanoaerylate, n-decyl cyanoaerylate, hexyl 2-cyanoacrylate, 2-ethoxyethyl 2- cyanoacrylate, 2-methoxyethyl 2-cyanoacrylate, 2-octyl 2-cyanoacrylate, 2-propoxyethyl 2-cyanoacrylate, n- octyl 2-cyanoacrylate and isoamyl cyanoaerylate. According to one particular embodiment, the cyanoacrylate monomers of formula (I) are chosen from those comprising alkyl or alkoxyalkyl radicals R containing from 1 to 10 carbon atoms and preferably from 6 to 10 carbon atoms.

Preferably, the cyanoacrylate monomer is chosen from (Cβ-Cio) alkyl cyanoacrylates .

The monomers that are particularly preferred are the octyl cyanoacrylates of formula (II) , and mixtures thereof:

C≡N

H₂C=C (II)

COO-R'₃ in which: R'₃ is chosen from - (CH₂) 7-CH₃, -CH (CH₃) -(CH₂)S-CH₃,

-CH₂-CH (C₂H₅) - (CH₂)₃-CH₃, -(CH₂) 5-CH(CH₃) -CH₃, -(CHs)₄-CH(C₂Hs)-CH₃, and mixtures thereof.

The cyanoacrylate monomer that is particularly preferred according to the invention is linear or branched octyl 2-cyanoacrylate, for instance the product sold under the trade reference Ritelok CDN 1064 by the company Chemence.

The monomers used in the first composition used in the invention may be covalently bonded to supports such as polymers, oligomers or dendrimers . The polymer or oligomer may be linear, branched, in comb form or in block form. The distribution of the monomers of the invention in the polymer, oligomer or dendrimer structure may be random, in the end position or in the form of blocks.

The cyanoacrylate monomers of formula (I) according to the present invention may be synthesized according to the known methods described in the art. In particular, the cyanoacrylate monomers may be synthesized according to the teaching of US 3 527 224, US 3 591 767, US 3 667 472, US 3 995 641, US 4 035 334 and US 4 650 826.

In the first composition, the amount of cyanoacrylate monomers may range from 0.1% to 100% by weight, better still from 1% to 50%, preferably from 2% to 30% and better still from 5% to 20% by weight relative to the total weight of the first composition.

In the context of the invention, the cyanoacrylate monomers of formula (I) are electrophilic monomers capable of undergoing anionic polymerization in the presence of a nucleophilic agent, for instance the hydroxide ions (OH^") contained in water at neutral pH.

The term "anionic polymerization" means the mechanism defined in the book "Advanced Organic Chemistry", third edition, by Jerry March, pages 151 to 161.

Nucleophilic agents

The nucleophilic agents capable of initiating the anionic polymerization are systems that are known per se, which are capable of generating a carbanion on contact with a nucleophilic agent, such as the hydroxide ions contained in water at neutral pH. The term "carbanion" means the chemical species defined in "Advanced Organic Chemistry", third edition, by Jerry March, page 141.

The nucleophilic agent is a molecular compound, an oligomer, a dendrimer or a polymer containing nucleophilic functions. In a non-limiting manner, nucleophilic functions that may be mentioned include the following functions: R₂N^", NH₂^", Ph₃C^", R₃C^", PhNH^", pyridine, ArS^", R-C≡C^", RS^", SH, RO^", R₂NH, ArO^", N₃^", OH^", ArNH₂, NH₃, I^", Br^", Cl^", RCOO^", SCN^", ROH, RSH, NCO^", CN^", NO₃^", ClO₄^" and H₂O, Ph representing a phenyl group; Ar representing an aryl group and R representing a Ci-Cio alkyl group.

The nucleophilic agents may be applied independently of the first composition of the invention, for example by prior application to the nails. They may also be added to the first composition at the time of use. According to one variant, they are present in the second composition used in the process according to the invention.

Preferably, this nucleophilic agent is water. This water may be already present on the support onto which the nail varnish is applied: it may especially be residual water naturally present in the nails; the water may also be provided, for example, by moistening the nails beforehand (for example with a mister) . It may also be added directly to the first composition before application, or alternatively it may be present in the second composition used in the process according to the invention, for example when this composition comprises an aqueous phase.

The nucleophilic agent may be used pure, as a solution or in the form of an emulsion, or may be encapsulated.

Polymerization inhibitors may also be introduced into the composition of the invention, and more particularly anionic and/or radical polymerization inhibitors, in order to increase the stability of the composition over time. In a non-limiting manner, mention may be made of the following polymerization inhibitors: sulfur dioxide, nitric oxide, organic acids such as a sulfonic acid or phosphoric acid, acetic acid, lactone, boron trifluoride, hydroquinone and derivatives thereof such as hydroquinone monoethyl ether or tert- butylhydroquinone, benzoquinone and derivatives thereof such as duroquinone, catechol and derivatives thereof such as t-butylcatechol and methoxycatechol, anisole and derivatives thereof such as methoxyanisole or hydroxyanisole, pyrogallol and derivatives thereof, p- methoxyphenol, butylhydroxytoluene, alkyl sulfates, alkyl sulfites, alkyl sulfones, alkyl sulfoxides, alkyl sulfides and mercaptans, and mixtures thereof. The alkyl groups preferably denote groups containing 1 to 6 carbon atoms .

The inhibitor concentration in the composition of the invention may range from 10 ppm to 10% and more preferentially from 50 ppm to 5% by weight.

Cosmetically acceptable medium

Needless to say, the first, second and optionally third compositions comprise a cosmetically acceptable medium, i.e. a non-toxic medium with a pleasant appearance, odour and feel, which may be applied to human nails.

Organic solvent phase

The first composition and/or the second composition advantageously comprises a liquid organic solvent phase comprising at least one organic solvent.

As organic solvents that may be used in the composition according to the invention, mention may be made of:

- short-chain esters (containing from 3 to 8 carbon atoms in total) , such as ethyl acetate, methyl acetate, propyl acetate, n-butyl acetate or isopentyl acetate;

- ketones that are liquid at room temperature, such as methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, isophorone, cyclohexanone or acetone;

- alcohols that are liquid at room temperature, such as ethanol, isopropanol, diacetone alcohol, 2-butoxyethanol or cyclohexanol; - glycols that are liquid at room temperature, such as ethylene glycol, propylene glycol, pentylene glycol or glycerol;

- propylene glycol ethers that are liquid at room temperature, such as propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate or dipropylene glycol mono-n-butyl ether;

- aldehydes that are liquid at room temperature, such as benzaldehyde or acetaldehyde; - carbonates such as propylene carbonate or dimethyl carbonate;

- acetals such as methylal; and

- mixtures thereof.

Preferably, the solvent is a volatile solvent chosen from short-chain esters (containing from 3 to 8 carbon atoms in total) such as ethyl acetate, methyl acetate, propyl acetate, n-butyl acetate, isopentyl acetate, and mixtures thereof.

Generally, the organic solvent phase (organic solvent or mixture of organic solvents) represents from 5% to 95% and preferably from 10% to 85% by weight relative to the total weight of each of the first and/or second composition.

According to one embodiment, the first and second compositions used in the process according to the invention are anhydrous, i.e. free of water other than the residual water provided by certain compounds.

Aqueous phase

The first and/or the second composition may comprise an aqueous phase consisting of water and optionally of water-soluble solvents.

According to one embodiment, the first composition is anhydrous and the second composition may comprise an aqueous phase.

In this case, the aqueous phase may represent from 5% to 95% by weight and preferably from 10% to 85% by weight relative to the total weight of the second composition.

Film-forming polymer

The first and/or the second composition advantageously comprise (s) a film-forming polymer.

The term "film-forming polymer" means a polymer that is capable, by itself or in the presence of an auxiliary film-forming agent, of forming a macroscopically continuous film on a support, for example keratin materials .

The film-forming polymer may be present in a content ranging from 0.1% to 60% by weight, preferably ranging from 2% to 40% by weight and better still from 5% to 25% by weight relative to the total weight of the first and/or the second composition.

According to a first variant, the film-forming polymer is a polymer chosen from the group comprising: film- forming polymers that are soluble or dispersible in at least one class of organic solvent, for instance ketones, alcohols, glycols and propylene glycol ethers, short-chain esters and alkanes, and aqueous or nonaqueous mixtures thereof.

The corresponding polymers may be of any chemical nature. In particular, they may result either from the homopolymerization or copolymerization of unsaturated monomers, or from polycondensation, or from the modification of natural polymers, in particular polysaccharides. The weight-average molecular masses

(Mp) of these polymers may range from 3000 to 1 000 000, especially from 5000 to 800 000 and in particular from 10 000 to 500 000.

Among the polymers that are soluble or dispersible in organic solvents, the following polymers are most particularly suitable: a) (meth) acrylic acid ester and/or amide homopolymers and copolymers, in particular polymers resulting from the polymerization or copolymerization of methyl, ethyl, propyl, butyl, isobutyl, tert-butyl, pentyl, hexyl, cyclohexyl, 2-ethylhexyl, heptyl, octyl, isobornyl, norbornyl or adamantyl acrylates and/or methacrylates, or the corresponding (meth) acrylamides . These polymers will preferably comprise from 0 to 20% of a polar comonomer such as (meth) acrylic acid, (meth) acrylamide, hydroxyethyl (meth) acrylate, 2- hydroxypropyl (meth) acrylate and (meth) acrylonitrile. They may also result from the copolymerization with styrene or a substituted styrene; b) vinyl ester or amide homopolymers and copolymers, in particular homopolymers and copolymers resulting from the polymerization of vinyl acetate, vinyl propionate or vinyl versatate, in the presence or absence of a polar comonomer such as crotonic acid, allyloxyacetic acid, maleic anhydride (or acid) , itaconic anhydride (or acid) , vinylacetamide and vinylformamide. Similarly, they may result from the copolymerization of at least one of the cited monomers with styrene or a substituted styrene; c) celluloses and cellulose derivatives, for instance nitrocelluloses and/or cellulose esters such as cellulose acetates, cellulose propionates, cellulose butyrates, cellulose acetopropionates and cellulose acetobutyrates . Film-forming polymers that may especially be used include nitrocellulose RS 1/8 sec; RS H sec; H sec; RS 5 sec; RS 15 sec; RS 35 sec; RS 75 sec; RS 150 sec; AS H sec; AS H sec; SS H sec; SS H sec; SS 5 sec, especially sold by the company Hercules; d) polycondensates that are soluble or dispersible in these solvents. They are generally used as main film- forming agent or as co-film-forming agent for one of the classes of polymers cited above (a to c) , in particular if they are of low molecular weight (Mp < 20 000) . They may be chosen from the following polymers or copolymers: polyurethanes, polyurethane-acrylics, polyureas, polyurea-polyurethanes, polyester- polyurethanes, polyether-polyurethanes, polyesters, polyesteramides, fatty-chain polyesters, epoxy resins, and arylsulfonamide condensates and in particular tosylamide/formaldehydes .

Among these polycondensates, in particular if they are used as film-forming agent or co-film-forming agent for one or more nitrocelluloses and/or a cellulose ester

(class c) , mention may be made more particularly of: polyesters, in particular fatty-chain polyesters and more particularly the copolymers having the CTFA names:

"phthalic anhydride/glycerol/glycidyl decanoate copolymer" and "adipic acid/neopentyl glycol/trimel- litic anhydride copolymer", alkyd resins, tosylamide/formaldehyde condensates , polyurethanes and polyurea-urethanes, acrylic resins, silicone resins (non-volatile or partially volatile) .

According to one embodiment of the invention, the film- forming polymer is a linear block ethylenic film- forming polymer, which preferably comprises at least one first block and at least one second block with different glass transition temperatures (Tg) , the said first and second blocks being linked together via an intermediate block comprising at least one constituent monomer of the first block and at least one constituent monomer of the second block.

Advantageously, the first and second blocks of the block polymer are mutually incompatible. Such polymers are described, for example, in document EP 1 411 069 or WO 04/028 488.

According to a second variant of the invention, the second composition comprises at least one film-forming polymer chosen from aqueous dispersions of polymer particles or film-forming latices, and, in this case, the second composition according to the invention comprises at least one aqueous phase.

The aqueous dispersion comprising one or more film- forming polymers may be prepared by a person skilled in the art on the basis of his general knowledge, especially by emulsion polymerization or by dispersing the preformed polymer.

Among the film-forming polymers of this type that may be used in the composition according to the present invention, mention may be made of synthetic polymers, of polycondensate type or of radical type, and polymers of natural origin, and mixtures thereof.

The polymers (homopolymers and copolymers) mentioned above may especially be used, but in latex form, as polymers that are soluble or dispersible in organic solvent medium, and more particularly the polymers of classes a, b and c.

Mention may thus be made, among the polycondensates, of anionic, cationic, nonionic or amphoteric polyurethanes, polyurethane-acrylics, polyurethane- polyvinylpyrrolidones, polyester-polyurethanes, polyether-polyurethanes, polyureas and polyurea- polyurethanes, and mixtures thereof.

Mention may also be made of polyesters, polyester- amides, fatty-chain polyesters, polyamides and epoxy ester resins. The polyesters may be obtained, in a known manner, by polycondensation of aliphatic or aromatic diacids with aliphatic or aromatic diols or polyols. Aliphatic diacids that may be used include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid and sebacic acid. Aromatic diacids that may be used include terephthalic acid and isophthalic acid, or alternatively a derivative such as phthalic anhydride. Aliphatic diols that may be used include ethylene glycol, propylene glycol, diethylene glycol, neopentyl glycol, cyclohexanedimethanol and 4, 4' - (1-methyl- propylidene)bisphenol. Polyols that may be used include glycerol, pentaerythritol, sorbitol and trimethylol- propane.

The polymers of radical type may especially be acrylic and/or vinyl polymers or copolymers. Anionic radical polymers are preferably used. As monomers bearing an anionic group that may be used during radical polymerization, mention may be made of acrylic acid, methacrylic acid, crotonic acid, maleic anhydride and 2-acrylamido-2-methylpropanesulfonic acid .

The acrylic polymers may result from the copolymerization of monomers chosen from acrylic acid or methacrylic acid esters and/or amides. Examples of monomers of ester type that may be mentioned include methyl methacrylate, ethyl methacrylate, butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate and lauryl methacrylate. Examples of monomers of amide type that may be mentioned include N- t-butylacrylamide and N-t-octylacrylamide.

The vinyl polymers may result from the homopoly- merization or copolymerization of monomers chosen from vinyl esters, styrene and butadiene. Examples of vinyl esters that may be mentioned include vinyl acetate, vinyl neodecanoate, vinyl pivalate, vinyl benzoate and vinyl t-butylbenzoate .

Acrylic/silicone copolymers may also be used.

Mention may also be made of polymers resulting from the radical polymerization of one or more radical monomers within and/or partially at the surface of pre-existing particles of at least one polymer chosen from the group consisting of polyurethanes, polyureas, polyesters, polyesteramides and/or alkyd resins. These polymers are generally known as hybrid polymers.

The dispersion may also comprise an associative polymer of polyurethane type or a natural gum such as xanthan gum.

Aqueous polymer dispersions that may be mentioned include the acrylic polymer dispersions sold under the names Neocryl XK-90^®, Neocryl A-1070^®, Neocryl A-1090^®, Neocryl BT-62^®, Neocryl A-1079^® and Neocryl A-523^® by the company Zeneca, and Dow Latex 432^® by the company Dow Chemical. Aqueous polyurethane dispersions may also be used, and especially the polyester-polyurethanes sold under the names Avalure UR-405^®, Avalure UR-410^®, Avalure UR-425^® and Sancure 2060^® by the company Goodrich, and the polyether-polyurethanes sold under the names Sancure 878^® by the company Goodrich and Neorez R-970^® by the company Avecia.

All the abovementioned film-forming polymers may be combined with at least one auxiliary film-forming agent .

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 a mixture, of common plasticizers or coalescers such as: glycols and derivatives thereof such as diethylene glycol ethyl ether, diethylene glycol methyl ether, diethylene glycol butyl ether, diethylene glycol hexyl ether, ethylene glycol ethyl ether, ethylene glycol butyl ether or 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 or propylene glycol butyl ether, acid esters, especially carboxylic acid esters, such as citrates, especially triethyl citrate, tributyl citrate, triethyl acetylcitrate, tributyl acetylcitrate or 2-triethylhexyl acetylcitrate; phthalates, especially diethyl phthalate, dibutyl phthalate, dioctyl phthalate, dipentyl phthalate or dimethoxyethyl phthalate; phosphates, especially tricresyl phosphate, tributyl phosphate, triphenyl phosphate or tributoxyethyl phosphate; tartrates, especially dibutyl tartrate; adipates; carbonates; sebacates; benzyl benzoate, butyl acetylricinoleate, glyceryl acetyl- ricinoleate, butyl glycolate, camphor, glyceryl triacetate or N-ethyl-o,p-toluenesulfonamide, oxyethylenated derivatives such as oxyethylenated oils, especially plant oils such as castor oil; silicone oils, 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 20% and in particular from 0.5% to 10% by weight relative to the total weight of each of the first and/or second composition.

Additives

Dyestuffs

The first, second and optionally third compositions used in the process according to the invention may comprise at least one dyestuff chosen, for example, from pigments, nacres (or nacreous pigments) , dyes and pigments with an effect, and mixtures thereof.

These dyestuffs may be present in a content ranging from 0.01% to 50% by weight, relative to the weight of the composition, and preferably from 0.01% to 30% by weight of each composition.

According to one particular embodiment, the composition comprising the electrophilic monomer is free of surface-untreated pigments, in particular pigments surface-untreated with an organic and/or hydrophobic agent, or not coated with an organic layer. Even more particularly, the composition comprising the electrophilic monomer is free of surface-untreated pigments and fillers.

The surface-treated pigments or fillers are pigments or fillers that have totally or partially undergone a surface treatment of chemical, electronic, electrochemical, mechanochemical or mechanical nature, with an agent such as those described especially in Cosmetics and Toiletries, February 1990, vol. 105, pp. 53-64.

According to another embodiment, the composition comprising the electrophilic monomer is free of pigments and more particularly of pigments and fillers. According to another embodiment, the composition comprising the electrophilic monomer according to the invention comprises a surface-treated pigment, in particular a pigment surface-treated with an organic and/or hydrophobic agent, or coated with an organic layer.

Preferably, the composition not comprising electrophilic monomer advantageously comprises at least one dyestuff.

i) Pigments and dyes

The dyestuff may be organic or inorganic, especially of the type such as 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 20% by weight, especially from 0.01% to 15% by weight and in particular from 0.02% to 10% by weight relative to the total weight of each of the first and second cosmetic compositions.

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.

It may also be a pigment 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 having 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 terms "nacres" and "nacreous pigments" should be understood as meaning coloured particles of any form, which may or may not be iridescent, especially produced by certain molluscs in their shell, or alternatively synthesized, and 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 commercially available nacres that may be mentioned are the nacres Timica, Flamenco and Duochrome

(on mica base) sold by the company Engelhard, the

Timiron nacres sold by the company Merck, the Prestige nacres on mica base sold by the company Eckart and the

Sunshine nacres on synthetic mica base sold by the company Sun Chemical .

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

As illustrations of nacres that may be used in the context of the present invention, mention may be made of 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 names 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 names Orange 363C (Cloisonne) and Orange MCR 101 (Cosmica) and by the company Merck under the names Passion orange (Colorona) and Matte orange (17449) (Microna) ; the brown-tinted nacres sold especially by the company Engelhard under the names 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-tinted nacres with a golden tint sold especially by the company Engelhard under the name Sunstone G012 (Gemtone) ; the pink nacres sold especially by the company Engelhard under the name Tan opale G005 (Gemtone) ; the black nacres with a golden 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 pinkish-orange nacres sold especially by the company Merck under the name Indian summer (Xirona) , and mixtures thereof.

The compositions 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 each 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.

ii) Pigment with an effect

The compositions of the process according to the invention may contain at least one material with a specific optical effect, which is especially present in the second composition. This effect is different from a simple conventional shade effect, i.e. a unified and stabilized effect as produced by the standard dyestuffs described above, for instance monochromatic pigments.

For the purposes of the invention, "stabilized" means lacking any effect of variability of the colour according to the angle of observation or in response to a change in temperature.

This material is present in an amount that is sufficient to produce an optical effect that is perceptible to the naked eye. Advantageously, it is an effect is chosen from goniochromatic effects, metallic and especially mirror effects, soft-focus effects, rainbow effects and/or thermochromic effects.

For example, this material may be chosen from particles with a metallic tint, goniochromatic colouring agents, diffractive pigments, thermochromic agents, optical brighteners and fibres, especially interference fibres.

Needless to say, these various materials may be combined in order simultaneously to afford two effects, or even a novel effect in accordance with the invention.

Particles with a metallic tint

The term "particles with a metallic tint" denotes particles whose nature, size, structure and surface state allow them to reflect the incident light, especially in a non-iridescent manner.

Particles with a substantially flat outer surface are also suitable, since they can, if their size, structure and surface state allow it, more easily give rise to a strong specular reflection, which may then be termed a mirror effect .

The particles with a metallic tint that may be used in the invention may, for example, reflect light in all the components of the visible region without significantly absorbing one or more wavelengths. The spectral reflectance of these particles may, for example, be greater than 70% and better still at least 80%, or even 90% or 95%, in the range 400-700 nm.

These particles generally have a thickness of less than or equal to 1 μm, especially less than or equal to 0.7 μm and in particular less than or equal to 0.5 μm.

The total proportion of particles with a metallic tint is especially less than or equal to 20% by weight and in particular less than or equal to 10% by weight relative to the total weight of the composition.

The particles with a metallic tint that may be used in the invention are in particular chosen from: particles of at least one metal and/or of at least one metal derivative, particles comprising a monomaterial or multimaterial organic or mineral substrate, at least partially coated with at least one layer with a metallic tint comprising at least one metal and/or at least one metal derivative, and mixtures of the said particles.

Among the metals that may be present in the said particles, mention may be made, for example, of Ag, Au, Cu, Al, Ni, Sn, Mg, Cr, Mo, Ti, Zr, Pt, Va, Rb, W, Zn, Ge, Te and Se and mixtures or alloys thereof. Ag, Au, Cu, Al, Zn, Ni, Mo and Cr, and mixtures or alloys thereof (for example bronzes and brasses) are preferred metals.

The term "metal derivatives" is intended to denote compounds derived from metals, especially oxides, fluorides, chlorides and sulfides.

Among the metal derivatives that may be present in the said particles, mention may be made especially of metal oxides, for instance titanium oxide, especially Tiθ₂, iron oxide, especially Fe₂O₃, tin oxide, chromium oxide, barium sulfate and the following compounds: MgF₂, CrF₃, ZnS, ZnSe, SiO₂, Al₂O₃, MgO, Y₂O₃, SeO₃, SiO, HfO₂, ZrO₂, CeO₂, Nb₂Os, Ta₂O₅, MoS₂, and mixtures or alloys thereof.

According to a first variant, the particles with a metallic tint may be composed of at least one metal as defined above, of at least one metal derivative as defined above, or of a mixture thereof. These particles may be at least partially covered with a layer of another material, for example of transparent material such as, especially, rosin, silica, stearates, polysiloxanes, polyester resins, epoxy resins, polyurethane resins or acrylic resins.

Illustrations of these particles that may be mentioned include aluminium particles, such as those sold under the names Starbrite 1200 EAC^® by the company Siberline and Metalure^® by the company Eckart.

Mention may also be made of metal powders of copper or of alloy mixtures such as the references 2844 sold by the company Radium Bronze, metallic pigments, for instance aluminium or bronze, such as those sold under the names Rotosafe^® 700 from the company Eckart, silica-coated aluminium particles sold under the name Visionaire Bright Silver^® from the company Eckart, and metal alloy particles, for instance the silica-coated bronze (alloy of copper and zinc) powders sold under the name Visionaire Bright Natural Gold^® from the company Eckart.

According to a second variant, these particles may be particles comprising a substrate, which thus have a multilayer structure, for example a two-layer structure. This substrate may be organic or mineral, natural or synthetic, monomaterial or multimaterial, solid or hollow. When the substrate is synthetic, it • may be made in a form promoting the formation of a reflective surface after coating, especially after depositing a layer of materials with a metallic tint.

The substrate may, for example, have a flat surface and the layer of materials with a metallic tint may have a substantially uniform thickness.

The substrate may be chosen in particular from the metals and metal derivatives as mentioned above, and also from glasses, ceramics, aluminas, silicas, silicates and especially aluminosilicates and borosilicates, synthetic mica such as fluorophlogopite, and mixtures thereof, this list not being limiting.

The layer with a metallic tint may totally or partially coat the substrate and this layer may be at least partially covered with a layer of another material, for example a transparent material especially as mentioned above. According to one particular embodiment, this layer with a metallic tint totally coats the substrate directly or indirectly, i.e. with interposition of at least one metallic or non-metallic intermediate layer.

The metals or metal derivatives that may be used in the reflective coat are as defined above. For example, it may be formed from at least one metal chosen from silver, aluminium, chromium, nickel, molybdenum, gold, copper, tin and magnesium, and mixtures (alloys) thereof. Silver, chromium, nickel and molybdenum, and mixtures thereof, are more particularly used.

As illustrations of particles of this second type, mention may be made more particularly of: Glass particles coated with a metallic layer, especially those described in documents JP-A-09188830, JP-A-10158450, JP-A-10158541, JP-A-07258460 and JP-A- 05017710.

As illustrations of these particles comprising a glass substrate, mention may be made of those coated, respectively, with silver, gold or titanium, in the form of platelets, sold by the company Nippon Sheet Glass under the name Microglass Metashine. Particles comprising a silver-coated glass substrate, in the form of platelets, are sold under the name Microglass Metashine REFSX 2025 PS by the company Toyal. Particles comprising a glass substrate coated with nickel/chromium/molybdenum alloy are sold under the name Crystal Star GF 550 and GF 2525 by this same company. Those coated either with brown iron oxide or with titanium oxide, tin oxide or a mixture thereof, for instance those sold under the name Reflecks^® by the company Engelhard or those sold under the name Metashine MC 2080GP by the company Nippon Sheet Glass.

These metal-coated glass particles may be coated with silica, for instance those sold under the name Metashine series PSSl or GPSl by the company Nippon Sheet Glass.

Particles comprising a spherical glass substrate optionally coated with a metal, especially those sold under the name ' Prizmalite Microsphere by the company Prizmalite Industries.

Pigments of the Metashine 1080R range sold by the company Nippon Sheet Glass Co. Ltd are also suitable for the invention. These pigments, more particularly described in patent application JP 2001-11340, are C- Glass glass flakes comprising 65% to 72% SiO₂, coated with a layer of titanium oxide of rutile type (TiO₂) . These glass flakes have a mean thickness of 1 micron and a mean size of 80 microns, i.e. a mean size/mean thickness ratio of 80. They have blue, green or yellow tints or a silver shade depending on the thickness of the TiO₂ layer.

Particles comprising a silver-coated borosilicate substrate, also known as "white nacres".

Particles comprising a metal substrate such as aluminium, copper or bronze, in the form of platelets, are sold under the trade name Starbrite by the company Silberline and under the name Visionaire by the company Eckart.

Particles comprising a synthetic mica substrate coated with titanium dioxide, and for example particles with a size of between 80 and 100 μm, comprising a synthetic mica (fluorophlogopite) substrate coated with titanium dioxide representing 12% of the total weight of the particle, sold under the name Prominence by the company Nihon Koken.

The particles with a metallic tint may also be chosen from particles formed from a stack of at least two layers with different refractive indices. These layers may be of polymeric or metallic nature and may especially include at least one polymeric layer.

The choice of materials intended to constitute the various layers of the multilayer structure is obviously made so as to give the particles thus formed the desired metallic effect.

Such particles are especially described in WO 99/36477, US 6 299 979 and US β 387 498 and more particularly identified below in the goniochromatic section.

Diffractive pigments

For the purposes of the present invention, the term "diffractive pigment" denotes a pigment capable of producing a colour variation according to the angle of observation when lit with white light, on account of the presence of a structure that diffracts light.

A diffractive pigment may comprise a diffracting network capable, for example, of diffracting an incident monochromatic light ray in defined directions.

The diffraction network may comprise a periodic unit, especially a line, the distance between two adjacent units being of the same order of magnitude as the wavelength of the incident light.

When the incident light is polychromatic, the diffraction network will separate the various spectral components of the light and produce a rainbow effect.

Reference may appropriately be made regarding the structure of diffractive pigments to the article "Pigments Exhibiting Diffractive Effects" by Alberto Argoitia and Matt Witzman, 2002, Society of Vacuum coaters, 45^th Annual Technical Conference Proceedings 2002.

The diffractive pigment may be made with units having different profiles, especially triangular, symmetrical or non-symmetrical, in gaps, of constant or non- constant width, or sinusoidal.

The spatial frequency of the network and the depth of the units will be chosen as a function of the degree of separation of the various orders desired. The frequency may range, for example, between 500 and 3000 lines per mm.

Preferably, the particles of the diffractive pigment each have a flattened form, and are especially in the form of platelets.

The same pigment particle may comprise two crossed, perpendicular or non-perpendicular diffraction networks .

A possible structure for the diffractive pigment may comprise a layer of a reflective material, covered at least on one side with a layer of a dielectric material. The latter material may give the diffractive pigment better rigidity and durability. The dielectric material may thus be chosen, for example, from the following materials: MgF₂, SiO₂, Al₂O₃, AlF₃, CeF₃, LaF₃, NdF₃, SmF₂, BaF₂, CaF₂, LiF and combinations thereof. The reflective material may be chosen, for example, from metals and alloys thereof, and also from non- metallic reflective materials. Among the metals that may be used, mention may be made of Al, Ag, Cu, Au, Pt, Sn, Ti, Pd, Ni, Co, Rd, Nb and Cr, and compounds, combinations or alloys thereof. Such a reflective material may, by itself, constitute the diffractive pigment, which will then be monolayer.

As a variant, the diffractive pigment may comprise a multilayer structure comprising a core of a dielectric material covered with a reflective layer at least on one side, or even totally encapsulating the core. A layer of a dielectric material may also cover the reflective layer (s). The dielectric material used is then preferably mineral, and may be chosen, for example, from metal fluorides, metal oxides, metal sulfides, metal nitrides, and metal carbides, and combinations thereof. The dielectric material may be in crystalline, semi-crystalline or amorphous form. In this configuration, the dielectric material may be chosen, for example, from the following materials: MgF₂, SiO, SiO₂, Al₂O₃, TiO₂, WO, AlN, BN, B₄C, WC, TiC, TiN, N₄Si₃, ZnS, glass particles and carbons of diamond type, and combinations thereof.

The diffractive pigment used may be chosen especially from those described in the American patent application US 2003/0 031 870 published on 13 February 2003.

A diffractive pigment may comprise, for example, the following structure: MgF₂/Al/MgF₂, a diffractive pigment having this structure being sold under the name

Spectraflair 1400 Pigment Silver by the company Flex

Products, or Spectraflair 1400 Pigment Silver FG. The weight proportion of MgF₂ may be between 80% and 95% of the total weight of the pigment.

Goniochromatic colouring agents

For the purposes of the invention, a goniochromatic colouring agent allows a colour change, also known as a "colour flop", to be observed as a function of the angle of observation, greater than that which may be encountered with nacres. One or more goniochromatic colouring agents may be used simultaneously.

The goniochromatic colouring agent may be chosen so as to present a relatively large colour change with the angle of observation.

The goniochromatic colouring agent may thus be chosen such that a colour difference ΔE of the cosmetic composition, measured in the CIE 1976 colorimetric space, of at least 2 may be observed for a variation of the angle of observation of between 0° and 80° under illumination at 45°.

The goniochromatic colouring agent may also be chosen such that a variation Dh of the hue angle of the cosmetic composition, in the CIE 1976 plane, of at least 30° or even at least 40° or at least 60°, or even at least 100°, may be observed for an illumination at 45° and a variation of the angle of observation of between 0° and 80°.

The goniochromatic colouring agent may be chosen, for example, from multilayer interference structures and liquid-crystal colouring agents.

In the case of a multilayer structure, it may comprise, for example, at least two layers, each layer, which may or may not be independent of the other layer (s), being made, for example, from at least one material chosen from the group consisting of the following materials: MgF₂, CeF₃, ZnS, ZnSe, Si, SiO₂, Ge, Te, Fe₂O₃, Pt, Va, Al₂O₃, MgO, Y₂O₃, S₂O₃, SiO, HfO₂, ZrO₂, CeO₂, Nb₂O₅, Ta₂O₅, TiO₂, Ag, Al, Au, Cu, Rb, Ti, Ta, W, Zn, MoS₂, cryolite, and alloys, polymers and combinations thereof. The multilayer structure may or may not have, relative to a central layer, symmetry in the chemical nature of the stacked layers.

Examples of symmetrical multilayer interference structures that may be used in the compositions prepared in accordance with the invention are, for example, the following structures: Al/SiC>₂/Al/Siθ₂/Al, pigments having this structure being sold by the company Dupont de Nemours; Cr/MgF₂/Al/MgF₂/Cr, pigments having this structure being sold under the name Chromaflair by the company Flex; MoS₂/Si0₂/Al/Siθ2/MoS₂;

Fe₂O₃ZSiO₂ZAlZSiO₂ZFe₂O₃, and Fe₂O₃ZSiO₂ZFe₂O₃ZSiO₂ZFe₂O₃, pigments having these structures being sold under the name Sicopearl by the company BASF; MoS₂ZSi0₂Zπιica- oxideZSi0₂ZMoS₂; Fe₂0₃ZSi0₂Zmica-oxideZSi0₂ZFe₂θ₃; TiO₂ZSiO₂ZTiO₂ and TiO₂ZAl₂O₃ZTiO₂;

SnOZTiO₂ZSiO₂ZTiO₂ZSnO; Fe₂O₃ZSiO₂ZFe₂O₃; SnθZmicaZTiO₂Z SiO₂ZTiO₂ZmicaZSnO, pigments having these structures being sold under the name Xirona by the company Merck

(Darmstadt) . By way of example, these pigments may be pigments of silicaZtitanium oxideZtin oxide structure sold under the name Xirona Magic by the company Merck, pigments of silicaZbrown iron oxide structure sold under the name Xirona Indian Summer by the company Merck, and pigments of silicaZtitanium oxideZmicaZtin oxide structure sold under the name Xirona Caribbean Blue by the company Merck. Mention may also be made of the Infinite Colors pigments from the company Shiseido. Depending on the thickness and the nature of the various layers, different effects are obtained. Thus, with the Fe₂O₃ZSiO₂ZAlZSiO₂ZFe₂O₃ structure, the colour changes from green-golden to red-grey for SiO₂ layers of 320 to 350 nm; from red to golden for SiO₂ layers of 380 to 400 nm; from violet to green for SiO₂ layers of 410 to 420 nm; from copper to red for SiO₂ layers of 430 to 440 nm. Goniochromatic colouring agents with a multilayer structure comprising an alternation of polymeric layers may also be used.

As illustrations of the materials that can constitute the various layers of the multilayer structure, it is possible to mention, this list not being limiting: polyethylene naphthalate (PEN) and its isomers, for example 2,6-, 1,4-, 1,5-, 2,7- and 2,3-PEN, polyalkylene terephthalates, polyimides, polyether- imides, atactic polystyrenes, polycarbonates, polyalkyl methacrylates and polyalkyl acrylates, syndiotactic polystyrene (sPS) , syndiotactic poly-alpha-methyl- styrenes, syndiotactic polydichlorostyrene, copolymers and blends of these polystyrenes, cellulose derivatives, polyalkylene polymers, fluoropolymers, chloropolymers, polysulfones, polyethersulfones, polyacrylonitriles, polyamides, silicone resins, epoxy resins, polyvinyl acetate, polyetheramides, ionomeric resins, elastomers and polyurethanes . Copolymers are also suitable, for example copolymers of PEN (for example copolymers of 2,6-, 1,4-, 1,5-, 2,7-, and/or 2, 3-naphthalenedicarboxylic acid or the esters thereof with (a) terephthalic acid or its esters; (b) isoph- thalic acid or its esters; (c) phthalic acid or its esters; (d) alkane glycols; (e) cycloalkane glycols (for example cyclohexanedimethanol diol) ; (f) alkanedicarboxylic acids; and/or (g) cycloalkane- dicarboxylic acids, polyalkylene terephthalate copolymers and styrene copolymers. In addition, each individual layer may include blends of two or more of the above polymers or copolymers. The choice of materials intended to constitute the various layers of the multilayer structure is, of course, made so as to give the particles thus formed the desired reflective appearance.

As examples of pigments with a polymeric multilayer structure, mention may be made of those sold by the company 3M under the name Color Glitter.

The liquid-crystal colouring agents comprise, for example, silicones or cellulose ethers onto which are grafted mesomorphic groups.

Examples of liquid-crystal goniochromatic particles that may be used include, for example, those sold by the company Chenix and also the products sold under the name Helicone^® HC by the company Wacker.

These agents may also be in the form of dispersed goniochromatic fibres. Such fibres may, for example, have a size of between 50 μm and 700 μm, for example about 300 μm.

Interference fibres with a multilayer structure may be used in particular. Fibres with a multilayer structure of polymers are described especially in documents EP-A-921 217, EP-A-686 858 and US-A-5 472 798. The multilayer structure may comprise at least two layers, each layer, which may or may not be independent of the other layer (s), being made of at least one synthetic polymer. The polymers present in the fibres may have a refractive index ranging from 1.30 to 1.82 and better still ranging from 1.35 to 1.75. The polymers that are preferred for making the fibres are polyesters such as polyethylene terephthalate, polyethylene naphthalate, polycarbonate; acrylic polymers such as polymethyl methacrylate; polyamides.

Goniochromatic fibres with a polyethylene terephthalate/nylon-6 two-layer structure are sold by the company Teijin under the name Morphotex.

In one variant, this goniochromatic colouring agent may be combined with at least one diffractive pigment.

The combination of these two materials results in a composition or a film that has increased colour variability, and thus which is capable of allowing an observer to see a colour change, or even a colour movement, under various observation and lighting conditions.

The weight ratio of the diffractive pigment relative to the goniochromatic colouring agent is preferably between 85/15 and 15/85, better still between 80/20 and 20/80 and better still between 60/40 and 40/60, for example about 50/50. Such a ratio is favourable towards obtaining a strong rainbow effect and a strong goniochromatic effect.

Optical brighteners

Optical brighteners are compounds that are well known to those skilled in the art. Such compounds are in particular described in "Fluorescent Whitening Agent, Encyclopedia of Chemical Technology, Kirk-Othmer", Vol. 11, pp. 227-241, 4th Edition, 1994, Wiley.

They may be defined more particularly as compounds that absorb essentially in the UVA range between 300 and 390 nm and re-emit essentially between 400 and 525 run.

Among the optical brighteners that may be mentioned more particularly are stilbene derivatives, in particular polystyrylstilbenes and triazinestilbenes, coumarin derivatives, in particular hydroxycoumarins and aminocoumarins, oxazole, benzoxazole, imidazole, triazole and pyrazoline derivatives, pyrene derivatives and porphyrin derivatives, and mixtures thereof.

Such compounds are widely commercially available. Mention may be made, for example, of: the naphthotriazole stilbene derivative sold under the trade name "Tinopal GS", disodium 4,4'- distyrylbiphenylsulfonate (CTFA name: disodium distyrylbiphenyl disulfonate) sold under the trade name "Tinopal CBS-X", the cationic aminocoumarin derivative sold under the trade name "Tinopal SWN Cone", the sodium 4,4' -bis [ (4, β-dianilino-1, 3, 5-triazin-2-yl) - amino] stilbene-2, 2' -disulfonate sold under the trade name "Tinopal SOP", the 4, 4' -bis [ (4-anilino-6~bis (2- hydroxyethyl) amino-1, 3, 5-triazin-2-yl) amino] stilbene- 2, 2' -disulfonic acid sold under the trade name "Tinopal UNPA-GX", the 4, 4' -bis [anilino-6-morpholine-l, 3, 5- triazin-2-yl) amino] stilbene sold under the trade name "Tinopal AMS-GX", the disodium 4, 4' -bis [ (4-anilino-β- (2-hydroxyethyl)methylamino-l, 3, 5-triazin-2-yl) amino] - stilbene-2, 2' -sulfonate sold under the trade name "Tinopal 5BM-GX", all by the company Ciba Specialites Chimiques,

2, 5-thiophenediylbis (5-tert-butyl-l, 3-benzoxazole) sold under the trade name "Uvitex OB" by the company Ciba, the anionic derivative of diaminostilbene as a dispersion in water, sold under the trade name "Leucophor BSB liquid" by the company Clariant, and the optical brightener lakes sold under the trade name "Covazur" by the company Wackherr.

The optical brighteners that may be used in the present invention may also be in the form of copolymers, for example acrylates and/or methacrylates, grafted with optical brightener groups as described in patent application FR 99/10942.

They may be used in unmodified form or introduced into the film in the form of particles and/or fibres coated with the said brightener, such as those described below.

In particular, the fibres coated with optical brightener as sold by the company LCW under the trade reference Fiberlon 54 ZO3, with a length of about 0.4 mm and a yarn count of 0.5 denier, may be used. As regards the fibres that may be used according to the invention, they may be mineral or organic fibres, of natural or synthetic origin.

The term "fibre" should be understood as meaning an object of length L and diameter D such that L is very much greater than D, D being the diameter of the circle in which the cross section of the fibre is inscribed. In particular, the ratio L/D (or shape factor) is chosen in the range from 3.5 to 2500, preferably from 5 to 500 and better still from 5 to 150.

They may especially be fibres used in the manufacture of textiles, and especially silk fibre, cotton fibre, wool fibre, flax fibre, cellulose fibre extracted in particular from wood, from plants or from algae, rayon fibre, polyamide (Nylon^®) fibre, viscose fibre, acetate fibre, especially rayon acetate fibre, poly(p- phenyleneterephthalamide) (or aramid) fibre, especially Kevlar^® fibre, acrylic polymer fibre, especially polymethyl methacrylate fibre or poly (2-hydroxyethyl methacrylate) fibre, polyolefin fibre and especially polyethylene or polypropylene fibre, glass fibre, silica fibre, carbon fibre, especially of carbon in graphite form, polytetrafluoroethylene (such as Teflon^®) fibre, insoluble collagen fibre, polyester fibre, polyvinyl chloride fibre or polyvinylidene chloride fibre, polyvinyl alcohol fibre, polyacrylo- nitrile fibre, chitosan fibre, polyurethane fibre, polyethylene phthalate fibre, and fibres formed from a mixture of polymers such as those mentioned above, for instance polyamide/polyester fibres.

The first composition, the second composition and/or the third composition may also contain one or more formulation additives commonly used in cosmetics and more especially in the cosmetics and/or nailcare field. They may be chosen especially from fragrances, vitamins, trace elements, softeners, sequestrants, acidifying or basifying agents, wetting agents, thickeners, dispersants, antifoams, spreading agents, co-resins, preserving agents, UV-screening agents, active agents, moisturizers, neutralizers, stabilizers and antioxidants, and mixtures thereof.

Thus, it may especially incorporate, as active agents, keratin material hardeners or strengtheners, active agents for promoting nail growth, such as methylsulfonylmethane, and/or active agents for treating various nail complaints, 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 0.01% to 10% by weight relative to the total weight of each composition.

The example that follows illustrates the invention in a non-limiting manner.

Example 1 : Nail makeup kit

1) First composition

Nitrocellulose containing 30% isopropyl 10.27 alcohol (viscosity: E22 - H S)

Nitrocellulose containing 30% isopropyl 2.83 alcohol (Azure E80 from Bergerac)

Glycerophthalic alkyd resin esterified with 15.16 branched fatty acids'¹' at 70% in ethyl acetate

Tributyl acetyl citrate 1.67

N-Ethyl-o,p-toluenesulfonamide 4.76

2-Octyl 2-cyanoacrylate stabilized with 1% 5 phosphoric acid (Ritelok CON895, sold by the company Chemence)

Isopropyl alcohol 3.32 Ethyl acetate 24.25

Butyl acetate qs 100

^(1> sold by Shell under the brand name Cardura 30^®

2) Second composition

Nitrocellulose containing 30% isopropyl 12.86 alcohol (viscosity: E22 - H S)

Nitrocellulose containing 30% isopropyl 1.51 alcohol (Azure E80 from Bergerac)

Glycerophthalic alkyd resin esterified with 16.08 branched fatty acids⁽¹⁾ at 70% in ethyl acetate

Tributyl acetyl citrate 3.25

N-Ethyl-o, p-toluenesulfonamide 3.57

Stearylbenzyldimethylammonium-modifled 1.29 hectorite

Lake Yellow 5 0.015

Lake Red 7 0.90

Lake Red 34 0.10

Isopropyl alcohol 3.66

Citric acid monohydrate 0.05

Ethyl acetate 23

Butyl acetate qs 100

(D sold by Shell under the brand name Cardura 30°

A coat of the first composition is applied to the nails and left to dry for a few seconds, then a coat of the second composition is applied onto the said coat. A coloured film that shows very good staying power over time is obtained on the nails.

Claims

1. Process for making up and/or caring for the nails, which consists in: a) applying to the nail at least one coat of a first composition free of pigment based on surface-untreated metal oxide, comprising at least one cyanoacrylate monomer of formula (I)

in which R represents an alkyl or alkoxyalkyl radical, b) and then applying onto the said coat at least one coat of a second composition comprising at least one film-forming polymer.

2. Process for making up and/or caring for the nails, which consists in: a) preparing an extemporaneous mixture:

- of at least one first composition comprising at least one cyanoacrylate monomer of formula (D

in which R represents an alkyl or alkoxyalkyl radical, and

- of at least one second composition comprising at least one film-forming polymer, and then b) applying to the nail at least one coat of the said mixture.

3. Process according to Claim 1 or 2, characterized in that the cyanoacrylate monomer (s) of formula (I) is (are) chosen from those in which the radical R contains from 1 to 10 carbon atoms.

4. Process according to the preceding claims, characterized in that the cyanoacrylate monomer (s) of formula (I) is (are) chosen from those comprising alkyl or alkoxyalkyl radicals R containing from 6 to 10 carbon atoms .

5. Process according to one of the preceding claims, characterized in that the cyanoacrylate monomer (s) is

(are) chosen from (Cβ-Cio) alkyl cyanoacrylates .

6. Process according to one of the preceding claims, characterized in that the cyanoacrylate monomer (s) is (are) chosen from the monomers of the following formula:

in which: R'₃ is chosen from -(CH₂J₇-CH₃,

-CH (CH₃) -(CH₂) 5-CH3, -CH₂-CH (C₂H₅) -(CH₂) 3-CH3,

-(CH₂)₅-CH(CH₃) -CH₃, -(CHs)₄-CH(C₂Hs)-CH₃, and mixtures thereof.

7. Process according to any one of the preceding claims, characterized in that the cyanoacrylate monomer is an n-octyl 2-cyanoacrylate.

8. Process for making up and/or caring for the nails, which consists in: a) applying to the nail at least one coat of a first composition comprising at least one n- octyl 2-cyanoacrylate monomer, b) and then applying onto the said coat at least one coat of a second composition.

9. Process according to any one of the preceding claims, characterized in that the amount of cyanoacrylate monomers ranges from 0.1% to 100% by weight, better still from 1% to 50%, preferably from 2% to 30% and better still from 5% to 20% by weight relative to the total weight of the first composition.

10. Process according to any one of the preceding claims, characterized in that the first and/or the second composition comprises an organic solvent phase.

11. Process according to the preceding claim, characterized in that the solvent phase comprises at least one organic solvent chosen from: - short-chain esters (containing from 3 to 8 carbon atoms in total) , such as ethyl acetate, methyl acetate, propyl acetate, n-butyl acetate or isopentyl acetate;

- alcohols that are liquid at room temperature, such as ethanol, isopropanol, diacetone alcohol, 2-butoxyethanol or cyclohexanol;

- glycols that are liquid at room temperature, such as ethylene glycol, propylene glycol, pentylene glycol or glycerol;

- acetals such as methylal; and

- mixtures thereof.

12. Process according to Claim 10 or 11, characterized in that the organic solvent phase represents from 5% to 95% and preferably from 10% to 85% by weight relative to the total weight of each of the first or second composition.

13. Process according to any one of the preceding claims, characterized in that the first and the second compositions are anhydrous.

14. Process according to any one of Claims 1 to 12, characterized in that the second composition comprises an aqueous phase.

15. Process according to Claim 14, characterized in that the aqueous phase represents from 5% to 95% by weight and preferably from 10% to 85% by weight relative to the total weight of the second composition.

16. Process according to any one of the preceding claims, characterized in that the first composition comprises at least one film-forming polymer.

17. Process according to Claim 1 or 16, characterized in that the film-forming polymer is present in a solids content ranging from 0.1% to 60% by weight, preferably ranging from 2% to 40% by weight and better still from 5% to 25% by weight relative to the total weight of the first and/or the second composition.

18. Process according to Claim 16 or 17, characterized in that the said film-forming polymer is chosen from (meth) acrylic acid ester and/or amide homopolymers and copolymers, vinyl ester or amide homopolymers and copolymers, celluloses and cellulose derivatives, polyurethanes, polyurethane-acrylics, polyureas, polyurea-polyurethanes, polyester-polyurethanes, polyether-polyurethanes, polyesters, polyesteramides, fatty-chain polyesters, epoxy resins and arylsulfonamide condensates.

19. Process according to one of the preceding claims, characterized in that the second composition comprises an aqueous dispersion of film-forming polymer particles .

20. Process according to Claim 19, characterized in that the said polymer is chosen from polycondensates, anionic, cationic, nonionic or amphoteric polyurethanes, polyurethane-acrylics, polyurethane- polyvinylpyrrolidones, polyester-polyurethanes, polyether-polyurethanes, polyureas, polyurea-polyure- thanes, polyesters, polyesteramides, fatty-chain polyesters, polyamides and epoxyester resins, acrylic and/or vinyl polymers or copolymers, acrylic/silicone or nitrocellulose/acrylic copolymers, polymers resulting from the radical polymerization of one or more radical monomers within and/or partially at the surface of pre-existing particles of at least one polymer chosen from the group consisting of polyurethanes, polyureas, polyesters and polyester- amides and/or alkyd resins.

21. Process according to one of the preceding claims, characterized in that the first and/or the second composition comprises at least one formulation additive chosen especially from co-resins, plasticizers, coalescers and spreading agents.

22. Process according to any one of Claims 2 to 21, characterized in that the composition comprises at least one dyestuff.

23. Process according to any one of Claims 2 to 22, characterized in that the first composition is free of pigment based on surface-untreated metal oxide.

24. Process according to any one of the preceding claims, characterized in that the second composition comprises at least one dyestuff.

25. Process according to one of Claims 20 to 24, characterized in that the dyestuff is present in a content ranging from 0.01% to 50% by weight and preferably from 0.01% to 30% by weight of each first and/or second composition.

26. Process according to one of the preceding claims, characterized in that it comprises an additional step that consists in applying at least one coat of a third liquid composition comprising a film-forming polymer and an organic or aqueous solvent medium to the coat(s) of second composition.

27. Kit for making up or caring for the nails, comprising: i) a first composition comprising at least one cyanoacrylate monomer of formula (I)

in which R represents an alkyl or alkoxyalkyl radical, and ii) a second composition comprising at least one film-forming polymer.

28. Kit for making up or caring for the nails according to Claim 27, characterized in that the first and second compositions are in separate packaging.