DESCRIPTION

TITLE: Process for dyeing the hair comprising the application of a (poly)carbodiimide compound, a compound comprising at least one carboxylic function, and a colouring agent comprising aluminium

The present invention relates to a process for dyeing the hair comprising the application to the hair of a composition C comprising a (poly)carbodiimide compound, a compound comprising at least one carboxylic function, and a particular colouring agent comprising aluminium.

Technical field

In the field of dyeing keratinous hair fibres, it is already known practice to colour keratinous hair fibres via various techniques using direct dyes or pigments for non-permanent colouring, or dye precursors for permanent colouring.

There are essentially three types of process for dyeing the hair: a) “permanent” dyeing, the function of which is to afford a substantial modification to the natural colour and which uses oxidation dyes which penetrate into the hair fibre and forms the dye via an oxidative condensation process; b) non-permanent, semi-permanent or direct dyeing, which does not use the oxidative condensation process and withstands four or five shampooing operations; it consists in dyeing keratinous fibres with dye compositions containing direct dyes; c) temporary dyeing, which gives rise to a modification of the natural colour of the hair that remains from one shampooing operation to the next, and which serves to enhance or correct a shade that has already been obtained. It may also be likened to a “makeup” process.

Another dyeing method consists in using pigments. Specifically, the use of pigment on the surface of keratinous fibres generally makes it possible to obtain visible colourings on dark hair, since the surface pigment masks the natural colour of the fibre. However, the colourings obtained by this dyeing method do not always have a satisfactory level of lightening, notably for dark hair.

In addition, temporary hair dye compositions may furthermore result in cosmetic properties that are not entirely satisfactory, notably in terms of coverage.

There is thus still a need for a process for dyeing the hair which has the advantage of obtaining a coloured coating on the hair having a good level of lightening and a good coverage. Thus, the objective of the present invention is to develop a process for dyeing the hair which has the advantage of obtaining a coloured coating on the hair exhibiting an improved level of lightening and an improved coverage.

Disclosure of the invention

The subject matter of the present invention is therefore a process for dyeing the hair, comprising the application to the hair of at least one composition C comprising:

- at least one (poly)carbodiimide compound;

- at least one compound comprising at least one carboxylic function; and

- at least one colouring agent comprising aluminium other than the colouring agents comprising at least one aluminosilicate.

By virtue of the hair dyeing process according to the invention, coloured coatings are obtained on the hair that make it possible to obtain a colouring that is visible on all types of hair with a very good level of lightening and also a very good coverage.

The expression "at least one” means one or more.

Unless otherwise indicated, the limits of a range of values are included in that range, particularly in the expressions "between" and "ranging from ... to ...".

The invention is not limited to the examples illustrated. The characteristics of the various examples may particularly be combined within variants which are not illustrated.

For the purposes of the present invention and unless otherwise indicated:

- an “alkyl” radical denotes a linear or branched saturated radical containing, for example, from 1 to 20 carbon atoms;

- an “amino alkyl” radical denotes an alkyl radical as defined previously, said alkyl radical comprising an NH2 group;

- a “hydroxy alkyl” radical denotes an alkyl radical as defined previously, said alkyl radical comprising an OH group;

- an “alkylene” radical denotes a linear or branched divalent saturated C2-C4 hydrocarbon-based group such as methylene, ethylene or propylene;

- a “cycloalkyl” or “alicycloalkyl” radical denotes a cyclic saturated monocyclic or polycyclic, preferably monocyclic, hydrocarbon-based group comprising from 1 to 3 rings, preferably 2 rings, and comprising from 3 to 24 carbon atoms, in particular comprising from 3 to 20 carbon atoms, more particularly from 3 to 13 carbon atoms, even more particularly from 3 to 12 carbon atoms, preferably between 5 and 10 carbon atoms, such as cyclopropyl, cyclopentyl, cyclohexyl, cycloheptyl or norbomyl, in particular cyclopropyl, cyclopentyl or cyclohexyl, it being understood that the cycloalkyl radical may be substituted with one or more (Ci- C4)alkyl groups such as methyl; preferably, the cycloalkyl radical is then an isobomyl group;

- a “ cycloalkylene” radical denotes a divalent cycloalkyl group with “cycloalkyl” as defined previously, preferably of C3-C12;

- an “aryl” radical is a monocyclic, bicyclic or tricyclic, fused or non-fused, unsaturated and aromatic hydrocarbon-based cyclic radical, comprising from 6 to 14 carbon atoms, preferably between 6 and 12 carbon atoms; preferably, the aryl group comprises 1 ring of 6 carbon atoms such as phenyl, naphthyl, anthryl, phenanthryl and biphenyl, it being understood that the aryl radical may be substituted with one or more (Ci-C4)alkyl groups such as methyl, preferably tolyl, xylyl, or methylnaphthyl; preferably, the aryl group represents phenyl;

- an “arylene” radical is a divalent aryl radical with “aryl” as defined previously; preferably, arylene represents phenylene;

- a “heterocyclic” radical denotes a saturated or unsaturated, non-aromatic or aromatic, monocyclic or polycyclic hydrocarbon-based radical, comprising one or more heteroatoms, preferably from 1 to 5 atoms chosen from O, S or N, including from 3 to 20 ring members, preferably between 5 and 10 ring members, such as imidazolyl, pyrrolyl and furanyl;

- a “heterocycloalkylene” radical is a divalent heterocyclic group with “heterocyclic” as defined previously;

- an “aryloxy” radical denotes an aryl-oxy radical with “aryl” as defined previously;

- an “alkoxy” radical denotes an alkyl-oxy radical with “alkyl” as defined previously;

- an “acyloxy” radical denotes an ester radical R-C(O)-O- with R being an alkyl group as defined above;

- a “reactive” group is a group that is capable of forming a covalent bond with another identical or different group, by chemical reaction.

Unless otherwise indicated, when compounds are mentioned in the present patent application, this also includes the optical isomers thereof, the geometric isomers thereof, the tautomers thereof or the salts thereof, alone or as a mixture.

"Keratinous hair fibres” means the hair. In other words, the expressions “keratinous hair fibres” and “hair” are equivalent in the remainder of the description.

For the purposes of the present invention, “hair” means head hair. This term does not correspond to body hair, the eyebrows or the eyelashes. Polycarbodiimide compound

Composition C used in the context of the process according to the invention comprises at least one (poly)carbodiimide compound.

The composition may comprise at least two different (poly)carbodiimide compounds, present as a mixture in the composition.

The term "'(poly carbodiimide compound” means a compound comprising one or more carbodiimide groups, preferably at least two carbodiimide groups, more preferentially at least three carbodiimide groups; in particular, the number of carbodiimide groups does not exceed 200, preferably 150, more preferentially 100.

The term “ carbodiimide group” means a divalent linear triatomic fraction of general formula -(N=C=N)-.

The (poly)carbodiimide compound(s) according to the invention may optionally comprise in their structure one or more reactive groups other than carbodiimide groups, chosen from alkoxysilyl, hydroxysilyl, acetoxysilyl, vinylsilyl, acrylalkylsilyl, methacrylalkylsilyl, crotonylalkylsilyl, carboxyanhydridoalkylsilyl, carboxyalkylsilyl, hydroxyalkylsilyl, aldehydoalkylsilyl, mercaptoalkylsilyl, norbomenylsilyl, acylpentadienylalkylsilyl, maleimidoalkylsilyl, sulfonylalkylsilyl, (meth)acrylalkyl, crotonylalkyl, alkylepoxide such as propylepoxide or butylepoxide and azacyclopropane groups.

The reactive group(s) other than the carbodiimide groups may be pendent or end groups. Preferably, the (poly)carbodiimide compound(s) comprise one or more end groups other than carbodiimide groups, preferably one or more end groups chosen from alkoxysilyl, hydroxysilyl, acetoxysilyl, vinylsilyl, acrylalkylsilyl, methacrylalkylsilyl, crotonylalkylsilyl, carboxyanhydridoalkylsilyl, carboxyalkylsilyl, hydroxyalkylsilyl, aldehydoalkylsilyl, mercaptoalkylsilyl, norbomenylsilyl, acylpentadienylalkylsilyl, maleimidoalkylsilyl, sulfonylalkylsilyl, (meth)acrylalkyl, crotonylalkyl, alkylepoxide such as propylepoxide or butylepoxide and azacyclopropane groups.

According to a particular embodiment, the (poly)carbodiimide compound is chosen from the compounds of formula (I) below:

(I), in which: - Xi and X2 independently represent an oxygen atom O, a sulfur atom S or an NH group;

- Ri and R2 independently represent a group chosen from a hydrocarbonbased radical, preferably alkyl, optionally interrupted with one or more heteroatom(s), a group chosen from alkoxysilyl, hydroxysilyl, acetoxysilyl, vinylsilyl, acrylalkylsilyl, methacrylalkylsilyl, crotonylalkylsilyl, carboxyanhydridoalkylsilyl, carboxyalkylsilyl, hydroxyalkylsilyl, aldehydoalkylsilyl, mercaptoalkylsilyl, norbornenylsilyl, acylpentadienylalkylsilyl, maleimidoalkylsilyl, sulfonylalkylsilyl, (meth)acrylalkyl, crotonylalkyl, alkylepoxide such as propylepoxide or butylepoxide and azacyclopropane groups, and a hydrocarbon-based radical, preferably alkyl, optionally interrupted with one or more heteroatom(s) and with one or more groups chosen from alkoxysilyl, hydroxysilyl, acetoxysilyl, vinylsilyl, acrylalkylsilyl, methacrylalkylsilyl, crotonylalkylsilyl, carboxyanhydridoalkylsilyl, carboxyalkylsilyl, hydroxyalkylsilyl, aldehydoalkylsilyl, mercaptoalkylsilyl, norbornenylsilyl, acylpentadienylalkylsilyl, maleimidoalkylsilyl, sulfonylalkylsilyl, (meth)acrylalkyl, crotonylalkyl, alkylepoxide such as propylepoxide or butylepoxide and azacyclopropane groups;

- n denotes an integer ranging from 1 to 1000; and

- A is a monomer chosen from the compounds below: According to another embodiment, the (poly)carbodiimide compound is chosen from the compounds of formula (I’) below:

(D in which:

- Xi and X2 independently represent an oxygen atom O, a sulfur atom S or an NH group;

- Y 1 and Y 2 independently represent a divalent organic radical chosen from a saturated Ci to C36 aliphatic group or a Ci, to C24 aromatic or alkylaromatic group, the aliphatic or aromatic group optionally comprising one or more non-pendent heteroatoms, such as a nitrogen atom, an oxygen atom, a sulfur atom, or combinations thereof;

- Zi and Z2 independently represent a reactive end group or an inert end group;

- as inert end group, Zi and Z2 may represent, independently, a saturated, linear or branched or cyclic Ci to C50 aliphatic group, or a Ci, to Cis aromatic group, said aliphatic and aromatic groups optionally comprising from 1 to 10 heteroatoms chosen from nitrogen, oxygen, sulfur and combinations thereof, and the aliphatic or aromatic group may be partially or totally fluorinated; in this variant, Zi and Z2 comprise a bonding group CG connecting Zi to Yi and Z2 to Y2, the group CG possibly being a single covalent bond, a saturated C-C bond, an unsaturated covalent C-C bond, an amide group, an ester group, a carbonate group, a thioester group, an ether group, a urethane group, a thiourethane group or a urea group;

- as reactive end group, Zi and Z2 may be chosen from alkoxysilyl, hydroxysilyl, acetoxysilyl, vinylsilyl, acrylalkylsilyl, methacrylalkylsilyl, crotonylalkylsilyl, carboxyanhydridoalkylsilyl, carboxyalkylsilyl, hydroxyalkylsilyl, aldehydoalkylsilyl, mercaptoalkylsilyl, norbomenylsilyl, acylpentadienylalkylsilyl, maleimidoalkylsilyl, sulfonylalkylsilyl, (meth)acrylalkyl, crotonylalkyl, alkylepoxide such as propylepoxide or butylepoxide and azacyclopropane groups;

- Q represents an organopolymer or an organooligomer comprising repeating units of saturated, linear or branched or cyclic aliphatic groups, or of aromatic groups or alkylaromatic groups, coupled via carbonate, ester, ether, amide, urethane or urea repeating bonds or combinations thereof;

- A represents a divalent aliphatic, aromatic, alkylaromatic or linear, saturated, branched or cyclic radical having from 2 to 30 carbon atoms, which may optionally comprise one or more non-pendent heteroatoms such as a nitrogen atom, an oxygen atom, a sulfur atom, or combinations thereof, in the aliphatic chain or the aromatic chain;

- r denotes an integer equal to 0 or 1 ;

- m denotes an integer ranging from 0 to 1000, preferably equal to 0 or 1;

- m’ denotes an integer ranging from 0 to 1000, preferably equal to 0 or 1;

- n denotes an integer ranging from 0 to 1000, preferably equal to 0 or 1, with m + (m’*n ) > 2.

Preferably, Zi and Z2 independently represent a reactive end group; more preferentially, Zi and Z2 independently represent a group chosen from alkoxy silyl, hydroxysilyl, acetoxysilyl, vinylsilyl, acrylalkylsilyl, methacrylalkylsilyl, crotonylalkylsilyl, carboxyanhydridoalkylsilyl, carboxyalkylsilyl, hydroxyalkylsilyl, aldehydoalkylsilyl, mercaptoalkylsilyl, norbomenylsilyl, acylpentadienylalkylsilyl, maleimidoalkylsilyl, sulfonylalkylsilyl, (meth)acrylalkyl, crotonylalkyl, alkylepoxide such as propylepoxide or butylepoxide and azacyclopropane groups.

Such (poly)carbodiimide compounds are sold, for example, by the company Stahl B.V, under the name Permutex XR, or under the name RelcaLinklO, under the name Picassian XL, and Nisshinbo compounds sold under the name Carbodilite with the series V-02, V-02-L2, SV-02, E-02, V-10, SW-12G, E-03A, E-04DG-T, E-05, V- 04, V-02B, V-04PF, V-05.

Preferably, the (poly)carbodiimide compound(s) is (are) chosen from the compounds of formula (II) below:

(II), in which:

- Xi and X2 independently represent an oxygen atom O, a sulfur atom S or an NH group; - Ri and R2 independently represent a hydrocarbon-based radical optionally interrupted with one or more heteroatom(s);

- n and z denote an integer ranging from 1 to 20, with n+z > 2 and w denoting an integer ranging from 1 to 3;

- Li independently represents a Ci-Cis divalent aliphatic hydrocarbon-based radical, a C3-C15 cycloalkylene radical, a C3-C12 heterocycloalkylene group or a Cf>- C14 arylene group, and mixtures thereof;

- E independently represents a group chosen from:

- -O-R3-O-; -S-R4-S-; -R ₅ -N(R ₆ )-R4-N(R ₆ )-R5-; in which R3 and R4 independently represent a divalent hydrocarbon-based radical optionally interrupted with one or more heteroatom(s);

- R5 independently represents a covalent bond or a saturated divalent hydrocarbon-based radical, optionally interrupted with one or more heteroatom(s);

- Re independently represents a hydrogen atom or a hydrocarbon-based radical, optionally interrupted with one or more heteroatom(s).

The term ^hydrocarbon-based radical” means a saturated or unsaturated, linear or branched radical having from 1 to 300 carbon atoms, preferably from 1 to 250 carbon atoms, more preferentially from 1 to 200 carbon atoms. Preferably, the hydrocarbon-based radical is a saturated linear radical.

The hydrocarbon-based radical may comprise one or more cyclic groups.

The hydrocarbon-based radical may be interrupted with one or more heteroatom(s), in particular chosen from O, S or N and/or substituted with one or more cation(s), anion(s) or zwitterion(s) or cationic group(s) such as ammonium, anionic group(s) such as carboxylate, or zwitterionic group(s), and/or comprising a metal ion which may be incorporated in the form of a salt.

The term “heteroatom(s)” means an oxygen O, sulfur S or nitrogen N atom, and also halogen atoms such as Cl, F, Br and I. If the heteroatom is included in the chain of the hydrocarbon-based radical, the heteroatom is preferably chosen from oxygen O, sulfur S or nitrogen N atoms.

Preferably, Xi and X2 independently represent an oxygen atom.

Preferably, Ri and R2 are independently chosen from dialkylamino alcohols, alkyl esters of hydroxycarboxylic acid and monoalkyl ethers of (poly)alkylene glycol, in which a hydroxyl group has been removed, and mixtures thereof.

In a preferred embodiment, Ri and R2 are independently chosen from groups (i) to (iv) below:

(i) the compound of formula (III) below:

R ₇ -O-C(O)-C(R ₈ )(H)- (III), in which R7 represents a C1-C3 alkyl group, and Rs represents a hydrogen atom or a C1-C3 alkyl group; preferably, R7 is a methyl and Rs is a hydrogen atom or a methyl.

(ii) the compound of formula (IV) below:

R ₉ -[0-CH2-C(H)(RIO)] _P - (IV), in which R9 represents a C1-C4 alkyl group, Rio represents a hydrogen atom or a C1-C4 alkyl group and p denotes an integer ranging from 1 to 3; preferably, R9 is a methyl, ethyl or butyl, Rio is a hydrogen atom or a methyl and p is equal to 1.

(iii) the compound of formula (V) below:

(Rii) ₂ N-CH ₂ -C(H)(Ri2)- (V), in which Rn represents a C1-C4 alkyl group and RI ₂ represents a hydrogen atom or a C1-C4 alkyl group; preferably, Rn is a methyl, ethyl or butyl and RI ₂ is a hydrogen atom or a methyl.

(iv) the compound of formula (VI) below:

Ri3-[O-CH ₂ -C(H)(Ri ₄ )] _q - (VI), in which R13 represents a C1-C4 alkyl group or a phenyl, R14 represents a hydrogen atom or a C1-C4 alkyl group and q denotes an integer ranging from 4 to 30; preferably, R 13 is a methyl, ethyl or butyl and R 14 is a hydrogen atom or a methyl.

Preferably, Ri and R ₂ independently represent a compound of formula (VI) in which R13 represents a C1-C4 alkyl group or a phenyl, preferably a C1-C4 alkyl group, more preferentially a methyl, R14 represents a hydrogen atom or a C1-C4 alkyl group, preferably a hydrogen atom and q denotes an integer ranging from 4 to 30.

According to an alternative embodiment, Ri and R ₂ are different and one of the radicals Ri or R ₂ represents a compound of formula (IV) as described above and the other radical Ri or R ₂ represents a compound of formula (VI) as described above.

Preferably, in formula (IV), R9 is a methyl, ethyl or butyl and Rio is a hydrogen atom or a methyl and p is equal to 1.

Preferably, in formula (VI), R13 is a methyl, ethyl or butyl and R14 is a hydrogen atom or a methyl and q denotes an integer ranging from 4 to 30.

According to another alternative embodiment, Ri and R ₂ are identical and represent a compound of formula (VI) in which R13 represents a C1-C4 alkyl group or a phenyl, preferably a C1-C4 alkyl group, more preferentially a methyl, R14 represents a hydrogen atom or a C1-C4 alkyl group, preferably a hydrogen atom and q denotes an integer ranging from 4 to 30.

Preferably, n denotes an integer ranging from 1 to 20, more preferentially from 2 to 20. Preferably, z denotes an integer ranging from 1 to 20, more preferentially from 2 to 20.

Preferably, w is equal to 1.

Preferably, w is equal to 1, n+z denotes an integer ranging from 4 to 10.

Preferably, Li is chosen from a Ci-Cis divalent aliphatic hydrocarbon-based radical such as methylene, ethylene and propylene, a C3-C 15 cycloalkylene radical such as cyclopentylene, cycloheptylene and cyclohexylene, a C3-C12 heterocycloalkylene group such as imidazolene, pyrrolene and furanylene, or a Ce-Cu arylene group such as phenylene, and mixtures thereof.

For example, Li may be chosen from a radical derived from tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, 2,2,4- trimethylhexamethylene diisocyanate, 1,12-dodecane diisocyanate, norbornane diisocyanate, 2,4-bis(8-isocyanatooctyl)-l,3-dioctylcyclobutane, 4,4’- dicyclohexylmethane diisocyanate, tetramethylxylylene diisocyanate, isophorone diisocyanate, 1,5-napththylene diisocyanate, 4,4’ -diphenylmethane diisocyanate, 4,4’- diphenyldimethylmethane diisocyanate and phenylene diisocyanate, and mixtures thereof.

Preferably, Li is chosen from a C3-C15 cycloalkylene radical or a Ce-Cu arylene group, and mixtures thereof, such as the compounds of formula (VII) below:

Preferably, Li is 4,4-dicyclohexylenemethane corresponding to formula (VIII) below:

(VIII).

According to another embodiment, when LI is a Ce-Cu arylene group, Li is not the m-tetramethylxylylene radical represented by formula (IX) below:

(IX).

As indicated previously, E independently represents a group chosen from:

- -O-R3-O-; -S-R4-S-; -R ₅ -N(R ₆ )-R4-N(R ₆ )-R5-; in which R3 and R4 independently represent a divalent hydrocarbon-based radical optionally interrupted with one or more heteroatom(s);

- R5 independently represents a covalent bond or a saturated divalent hydrocarbon-based radical, optionally interrupted with one or more heteroatom(s); and

- Re independently represents a hydrogen atom or a hydrocarbon-based radical, optionally interrupted with one or more heteroatom(s).

Preferably, R3 and R4 are independently chosen from a Ce-Cu arylene radical such as phenylene, a C3-C12 cycloalkylene radical such as cyclopropylene and cyclobutylene, a linear or branched Ci-Cis alkylene radical such as methylene and ethylene, optionally interrupted with one or more heteroatom(s), and mixtures thereof.

More preferentially, R3 and R4 are independently chosen from a linear or branched Ci-Cis alkylene radical such as methylene, butylene, propylene, ethylene, optionally interrupted with one or more heteroatom(s).

Preferably, when R5 is not a covalent bond, R5 is chosen from a C6-C14 arylene radical such as phenylene, a C3-C12 cycloalkylene radical such as cyclopropylene and cyclobutylene, a linear or branched Ci-Cis alkylene radical such as methylene and ethylene, optionally interrupted with one or more heteroatom(s), and mixtures thereof.

Preferably, Re is chosen from a Ce-Cu arylene radical such as phenylene, a C3-C12 cycloalkylene radical such as cyclopropylene and cyclobutylene, a linear or branched Ci-Cis alkylene radical such as methylene and ethylene, optionally interrupted with one or more heteroatom(s), and mixtures thereof. Preferably, E represents a group -O-R3-O- in which R3 is chosen from a Ce- C14 arylene radical, a C3-C12 cycloalkylene radical, a linear or branched Ci-Cis alkylene radical, optionally interrupted with one or more heteroatom(s), and mixtures thereof.

More preferentially, E represents a group -O-R3-O- in which R3 represents a linear or branched Ci-Cis alkylene radical such as methylene, butylene, propylene, ethylene, optionally interrupted with one or more heteroatom(s).

According to a particular embodiment, the (poly)carbodiimide compound is a copolymer derived from alpha-methylstyryl isocyanates of formula (X) below:

(X), in which R independently represents an alkyl group having from 1 to 24 carbon atoms, a cycloalkyl group having from 3 to 24 carbon atoms or an aryl group having from 6 to 24 carbon atoms, and n denotes an integer ranging from 2 to 100.

In this embodiment, the term “alkyl group” is as defined previously.

In this embodiment, the term “cycloalkyl group” is as defined previously.

In this embodiment, n may denote an integer ranging from 2 to 50, preferably from 3 to 30 and even more preferentially from 5 to 10.

According to another particular embodiment, the (poly)carbodiimide compound is a compound of formula (XI) below:

(XI), in which R independently represents an alkyl group having from 1 to 24 carbon atoms, a cycloalkyl group having from 3 to 24 carbon atoms or an aryl group having from 6 to 24 carbon atoms.

The “alkyl group”, the “cycloalkyl group” and the “aryl group” are as defined previously. According to a preferred embodiment, the (poly)carbodiimide compound is chosen from the compounds of formula (I) or of formula (II) in which:

- Xi and X2 independently represent an oxygen atom;

- Ri and R2 are independently chosen from dialkylamino alcohols, alkyl esters of hydroxycarboxylic acid and monoalkyl ethers of (poly)alkylene glycol, in which a hydroxyl group has been removed, and mixtures thereof, preferably monoalkyl ethers of (poly)alkylene glycol, in which a hydroxyl group has been removed, more preferentially the compound of formula (VI) as described previously in which R13 represents a C1-C4 alkyl group or a phenyl, preferably a C1-C4 alkyl group, more preferentially a methyl, R14 represents a hydrogen atom or a C1-C4 alkyl group, preferably a hydrogen atom, and q denotes an integer ranging from 4 to 30;

- n and z, when they are present, denote an integer ranging from 1 to 20, with n+z > 2 and w is equal to 1 ;

- Li, when it is present, is chosen from a Ci-Cis divalent aliphatic hydrocarbon-based radical, a C3-C15 cycloalkylene radical, a C3-C12 heterocycloalkylene group or a Cf>- C14 arylene group, and mixtures thereof, preferably a C3-C15 cycloalkylene radical;

- A, when it is present, is chosen from a Ci-Cis divalent aliphatic hydrocarbon-based radical, a C3-C15 cycloalkylene radical, a C3-C12 heterocycloalkylene group or a Cf>- C14 arylene group, and mixtures thereof, preferably a C3-C15 cycloalkylene radical;

- E, when it is present, independently represents a group chosen from:

- -O-R3-O-; -S-R4-S-; -R ₅ -N(R ₆ )-R4-N(R ₆ )-R5-; in which R3 and R4 are independently chosen from a C6-C14 arylene radical, a C3-C12 cycloalkylene radical, a linear or branched Ci-Cis alkylene radical, optionally interrupted with one or more heteroatom(s), and mixtures thereof;

- when R5 is not a covalent bond, R5, when it is present, is chosen from a C6-C14 arylene radical, a C3-C12 cycloalkylene radical, a linear or branched Ci-Cis alkylene radical, optionally interrupted with one or more heteroatom(s), and mixtures thereof; and

- Re, when it is present, is chosen from a Ce-Cu arylene radical, a C3-C12 cycloalkylene radical, a linear or branched Ci-Cis alkylene radical, optionally interrupted with one or more heteroatom(s), and mixtures thereof.

Preferably, the (poly)carbodiimide compound is chosen from the compounds of formula (II) in which:

- Xi and X2 independently represent an oxygen atom;

- Ri and R2 are independently chosen from dialkylamino alcohols, alkyl esters of hydroxycarboxylic acid and monoalkyl ethers of (poly)alkylene glycol, in which a hydroxyl group has been removed, and mixtures thereof; - n and z denote an integer ranging from 1 to 20, with n+z > 2 and w is equal to 1;

- Li is chosen from a Ci-Cis divalent aliphatic hydrocarbon-based radical, a C3-C15 cycloalkylene radical, a C3-C12 heterocycloalkylene group or a Ce-Cu arylene group, and mixtures thereof;

- E independently represents a group chosen from:

- -O-R3-O-; -S-R4-S-; -R ₅ -N(R ₆ )-R4-N(R ₆ )-R5-; in which R3 and R4 are independently chosen from a C6-C14 arylene radical, a C3-C12 cycloalkylene radical, a linear or branched Ci-Cis alkylene radical, optionally interrupted with one or more heteroatom(s), and mixtures thereof;

- when R5 is not a covalent bond, R5 is chosen from a C6-C14 arylene radical, a C3- C12 cycloalkylene radical, a linear or branched Ci-Cis alkylene radical, optionally interrupted with one or more heteroatom(s), and mixtures thereof; and

- Re is chosen from a Ce-Cu arylene radical, a C3-C12 cycloalkylene radical, a linear or branched Ci-Cis alkylene radical, optionally interrupted with one or more heteroatom(s), and mixtures thereof.

More preferentially, the (poly)carbodiimide compound is chosen from the compounds of formula (II) in which:

- Xi and X2 independently represent an oxygen atom;

- Ri and R2 are, independently, monoalkyl ethers of (poly)alkylene glycol, in which a hydroxyl group has been removed;

- n and z denote an integer ranging from 1 to 20, with n+z > 2 and w is equal to 1;

- Li is a C3-C15 cycloalkylene radical;

- E independently represents a group chosen from:

- -O-R3-O-; -S-R4-S-; -R ₅ -N(R ₆ )-R4-N(R ₆ )-R5-; in which R3 and R4 are independently chosen from a C6-C14 arylene radical, a C3-C12 cycloalkylene radical, a linear or branched Ci-Cis alkylene radical, optionally interrupted with one or more heteroatom(s), and mixtures thereof;

- when R5 is not a covalent bond, R5 is chosen from a C6-C14 arylene radical, a C3- C12 cycloalkylene radical, a linear or branched Ci-Cis alkylene radical, optionally interrupted with one or more heteroatom(s), and mixtures thereof; and

- Re is chosen from a Ce-Cu arylene radical, a C3-C12 cycloalkylene radical, a linear or branched Ci-Cis alkylene radical, optionally interrupted with one or more heteroatom(s), and mixtures thereof.

Even more preferentially, the (poly)carbodiimide compound is chosen from the compounds of formula (II) in which:

- Xi and X2 independently represent an oxygen atom;

- Ri and R2 independently represent the compound of formula (VI) below: Ri3-[O-CH ₂ -C(H)(Ri ₄ )] _q - (VI), in which R13 represents a C1-C4 alkyl group or a phenyl, preferably a C1-C4 alkyl group, more preferentially a methyl, R14 represents a hydrogen atom or a C1-C4 alkyl group, preferably a hydrogen atom, and q denotes an integer ranging from 4 to 30;

- n and z denote an integer ranging from 2 to 20, with n+z ranging from 4 to 10 and w is equal to 1 ;

- Li is a C3-C15 cycloalkylene radical such as cyclopentylene, cycloheptylene, cyclohexylene and 4,4-dicyclohexylenemethane; and

- E represents a group -O-R3-O- wherein R3 is chosen from a C6-C14 arylene radical, a C3-C12 cycloalkylene radical, a linear or branched Ci-Cis alkylene radical, optionally interrupted with one or more heteroatom(s), and mixtures thereof.

Even more preferentially, the (poly)carbodiimide compound is chosen from the compounds of formula (II) in which:

- Xi and X ₂ independently represent an oxygen atom;

- Ri and R2 independently represent the compound of formula (VI) below:

Ri3-[O-CH ₂ -C(H)(Ri ₄ )] _q - (VI) in which R13 represents a C1-C4 alkyl group or a phenyl, preferably a C1-C4 alkyl group, more preferentially a methyl, R14 represents a hydrogen atom or a C1-C4 alkyl group, preferably a hydrogen atom, and q denotes an integer ranging from 4 to 30;

- n and z denote an integer ranging from 2 to 20, with n+z ranging from 4 to 10 and w is equal to 1 ;

- Li is a C3-C15 cycloalkylene radical such as cyclopentylene, cycloheptylene, cyclohexylene and 4,4-dicyclohexylenemethane, preferably 4,4- dicyclohexylenemethane; and

- E represents a group -O-R3-O- in which R3 represents a linear or branched Ci-Cis alkylene radical such as methylene, propylene, butylene, ethylene, optionally interrupted with one or more heteroatom(s).

According to a preferred embodiment, the (poly)carbodiimide compound is a compound of formula (XII) below:

(XII), in which LI is 4,4-dicyclohexylenemethane, n and z denote an integer ranging from 2 to 20, with n+z ranging from 4 to 10, E represents a group -O-R3-O- in which R3 represents a linear or branched Ci-Cis alkylene radical such as methylene, propylene, butylene, ethylene, optionally interrupted with one or more heteroatom(s), and r and s denote an integer ranging from 4 to 30.

Advantageously, the total amount of the (poly)carbodiimide compound(s) ranges from 0.01 to 20% by weight, preferably from 0.1 to 15% by weight, more preferentially from 0.2 to 10% by weight, even more preferentially from 0.5 to 8%, better still from 1 to 6% by weight relative to the total weight of composition C.

Compound having at least one carboxylic function

Composition C used in the context of the process according to the invention comprises at least one compound having at least one carboxylic function.

Preferably, the compound having at least one carboxylic function is chosen from silicone compounds comprising at least one carboxylic group, polyurethanes, acrylic polymers and mixtures thereof.

Polyurethanes and acrylic polymers

According to a preferred embodiment, composition C comprises at least one compound having at least one carboxylic function chosen from polyurethanes, acrylic polymers and mixtures thereof. Preferably, the compound(s) having at least one carboxylic function are in the form of aqueous dispersions of particles of polymer(s) chosen from polyurethanes, acrylic polymers and mixtures thereof.

Preferably, composition C comprises at least one compound having at least one carboxylic function, in the form of aqueous dispersions of particles of polyurethanes, of acrylic polymers, and mixtures thereof.

The dispersion(s) may be simple dispersions in the aqueous medium of the cosmetic composition. As a particular case of dispersions, mention may be made of latexes.

The aqueous dispersion(s) of polymer particles may be chosen from aqueous dispersions of polyurethane particles.

More particularly, the polyurethane(s) present in the aqueous dispersions used in the present invention result from the reaction of:

- a prepolymer of formula (A) below:

(A), in which

- Ri represents a divalent radical of a dihydroxylated compound;

- R2 represents a radical of an aliphatic or cycloaliphatic polyisocyanate;

- R3 represents a radical of a low molecular weight diol, optionally substituted with one or more ionic groups;

- n represents an integer ranging from 1 to 5, and

- m is greater than 1 ;

- at least one chain extender according to formula (B) below:

H2N-R4-NH2 (B), in which R4 represents an alkylene or alkylene oxide radical which is not substituted with one or more ionic or potentially ionic groups; and

- at least one chain extender according to formula (C) below:

H2N-R5-NH2 (C), in which R5 represents an alkylene radical substituted with one or more ionic or potentially ionic groups.

Among the dihydroxylated compounds that may be used according to the present invention, mention may be made particularly of the compounds having two hydroxyl groups and having a number-average molecular weight from approximately 700 to approximately 16000, and preferably from approximately 750 to approximately 5000. By way of example of dihydroxylated compounds having a high molecular weight, mention may be made of polyol polyesters, polyol poly ethers, poly hydroxylated polycarbonates, poly hydroxylated poly acetates, poly hydroxylated polyacrylates, polyhydroxylated amide polyesters, polyhydroxylated poly alkadienes, polyhydroxylated poly thioethers, and mixtures thereof. Preferably, the hydroxylated compounds are chosen from polyol polyesters, polyol polyethers, polyhydroxylated polycarbonates, and mixtures thereof.

The polyisocyanates that may be used according to the present invention are particularly chosen from organic diisocyanates having a molecular weight of approximately 112 to 1000, and preferably approximately 140 to 400.

Preferably, the polyisocyanates are chosen from diisocyanates and more particularly from those represented by the general formula R2(NCO)2, in which R2 represents a divalent aliphatic hydrocarbon-based group having from 4 to 18 carbon atoms, a divalent cycloaliphatic hydrocarbon-based group having from 5 to 15 carbon atoms, a divalent araliphatic hydrocarbon-based group having from 7 to 15 carbon atoms or a divalent aromatic hydrocarbon-based group having from 6 to 15 carbon atoms.

Preferably, R2 represents an organic diisocyanate. By way of example of organic diisocyanates, the following may particularly be chosen: tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, dodecamethylene diisocyanate, 1,3- diisocyanatocyclohexane, 1,4-diisocyanatocyclohexane, 3-isocyanatomethyl-3,5,5- trimethylcyclohexane isocyanate (isophorone diisocyanate or IPDI), bis(4- isocyanatocyclohexyl)methane, 1 ,3-bis(isocyanatomethyl)cyclohexane, 1 ,4- bis(isocyanatomethyl)cyclohexane, bis(4-isocyanato-3-methyl-cyclohexyl)methane, isomers of toluene diisocyanate (TDI) such as toluene 2,4-diisocyanate, toluene 2,6- diisocyanate and mixtures thereof, hydrogenated toluene diisocyanate, diphenylmethane 4,4’ -diisocyanate and mixtures with its diphenylmethane 2,4- diisocyanate isomers and optionally diphenylmethane 2,2'-diisocyanate , naphthalene 1,5-diisocyanate isomers, and mixtures thereof.

Preferably, the diisocyanates are aliphatic and cycloaliphatic diisocyanates, and are more preferentially chosen from 1,6-hexamethylene diisocyanate, 3- isocyanatomethyl-3,5,5-trimethylcyclohexane isocyanate, and mixtures thereof.

According to the present invention, "low molecular weight diol" means a diol having a molecular weight from approximately 62 to 700, and preferably from 62 to 200. These diols may comprise aliphatic, alicyclic or aromatic groups. Preferably, they comprise only aliphatic groups.

Preferably, R3 represents a low molecular weight diol having more than 20 carbon atoms, more preferentially chosen from ethylene glycol, diethylene glycol, 1,2- propanediol, 1,3 -propanediol, 1,4-butanediol, 1,3-butylene glycol, neopentyl glycol, butylethylpropanediol, cyclohexanediol, 1,4-cyclohexanedimethanol, 1,6-hexanediol, bisphenol A (2,2-bis(4-hydroxyphenyl)propane), hydrogenated bisphenol A (2,2- bis(4-hydroxycyclohexyl)propane), and mixtures thereof.

The low molecular weight diols may optionally comprise ionic or potentially ionic groups. Examples of low molecular weight diols containing ionic or potentially ionic groups are particularly described in patent US 3 412 054. Such compounds are preferably chosen from dimethylolbutanoic acid, dimethylolpropionic acid, polycaprolactone diols containing a carboxyl group, and mixtures thereof.

If low molecular weight diols containing ionic or potentially ionic groups are used, they are preferably used in an amount such that less than 0.30 meq of COOH per gram of polyurethane is present in the polyurethane dispersion.

The prepolymer is extended by means of two chain extender families. The first family of chain extenders corresponds to the compounds of general formula (B).

The chain extenders of formula (B) are preferably chosen from alkylenediamines, such as hydrazine, ethylenediamine, propylenediamine, 1,4- butylenediamine, piperazine; alkylene oxide diamines, such as 3-{2-[2-(3- aminopropoxy)ethoxy] ethoxy (propylamine (also known as dipropylamine diethylene glycol or DPA-DEG available from Tomah Products, Milton, Wis.), 2-methyl-l,5- pentanediamine (Dytec A from DuPont), hexanediamine, isophorone diamine, 4,4- methylenedi(cyclohexylamine), ether-amines of the DPA series, available from Tomah Products, Milton, Wis., such as dipropylamine propylene glycol, dipropylamine dipropylene glycol, dipropylamine tripropylene glycol, dipropylamine polypropylene glycol), dipropylamine ethylene glycol, dipropylamine poly (ethylene glycol), dipropylamine 1,3-propanediol, dipropylamine 2-methyl- 1,3 -propanediol, dipropylamine 1,4-butanediol, dipropylamine 1,3-butanediol, dipropylamine 1,6- hexanediol and dipropylamine cyclohexane- 1,4-dimethanol; and mixtures thereof.

The second family of chain extenders corresponds to the compounds of general formula (C). Such compounds preferably have an ionic or potentially ionic group and two groups that can react with isocyanate groups. Such compounds may optionally comprise two groups that react with isocyanate groups and one group which is ionic or capable of forming an ionic group. The ionic or potentially ionic group may preferably be chosen from ternary or quaternary ammonium groups or groups that can be converted into such groups, a carboxyl group, a carboxylate group, a sulfonic acid group and a sulfonate group. The at least partial conversion of groups that can be converted into a ternary or quaternary ammonium group salt may be performed before or during the mixing with water.

The chain extenders of formula (C) are preferably chosen from diaminosulfonates, for instance the sodium salt of N-(2-aminoethyl)-2- aminoethanesulfonic acid (ASA), the sodium salt of N-(2-aminoethyl)-2- aminopropionic acid, and mixtures thereof.

The polyurethane that may be used according to the present invention may optionally also comprise compounds which are located, respectively, at the chain ends and terminate said chains (chain terminators). Such compounds are particularly described in patents US 7 445 770 and/or US 7 452 770.

Preferably, the aqueous dispersion of polyurethane particles has a viscosity of less than 2000 mPa.s at 23°C, more preferentially less than 1500, and even better still less than 1000. Even more preferably, the aqueous polyurethane dispersion has a glass transition temperature of less than 0°C.

Preferably also, the aqueous polyurethane dispersion has a polyurethane (or active material, or dry matter) content, on the basis of the weight of the dispersion, of from 20% to 60% by weight, more preferentially from 25% to 55% by weight and even better still from 30% to 50% by weight. This means that the polyurethane content (dry matter) of the aqueous dispersion is preferably from 20% to 60% by weight, more preferentially from 25% to 55% by weight and even better still from 30% to 50% by weight, relative to the total weight of the dispersion.

Preferably also, the aqueous dispersion of polyurethane particles has a glass transition temperature (Tg) of less than or equal to -25°C, preferably less than -35°C and more preferentially less than -40°C.

The polyurethane particles may have a mean diameter ranging up to approximately 1000 nm, for example from approximately 50 nm to approximately 800 nm, better still from approximately 100 nm to approximately 500 nm. These particle sizes may be measured with a laser particle size analyser (for example Brookhaven BI90).

As non-limiting examples of aqueous polyurethane dispersions, mention may be made of those sold under the name Baycusan® by Bayer, for instance Baycusan® C1000 (INCI name: polyurethane-34), Baycusan® C1001 (INCI name: polyurethane- 34), Baycusan® C1003 (INCI name: polyurethane-32), Baycusan® C1004 (INCI name: polyurethane-35) and Baycusan® C1008 (INCI name: polyurethane-48). Mention may also be made of the aqueous polyurethane dispersions of isophthalic acid/adipic acid copolymer/hexylene glycol/neopentyl glycol/dimethylol acid/isophorone diisocyanate (INCI name: Polyurethane- 1, such as Luviset® PUR, BASF), the polyurethane of polycarbonate, polyurethane and aliphatic polyurethane of aliphatic polyester (such as the Neorez® series, DSM, such as Neorez® R989, Neorez® and R-2202).

According to a preferred embodiment, the aqueous dispersion of polyurethane particles may be chosen from aqueous dispersions of particles of compounds having the INCI name polyurethane-35 or compounds having the INCI name polyurethane - 34.

Preferably, the compound(s) having at least one carboxylic function are in the form of aqueous dispersions of particles of acrylic polymers, more preferentially in the form of aqueous dispersions of film-forming acrylic polymer particles.

For the purposes of the invention, “polymer” means a compound corresponding to the repetition of one or more units (these units being derived from compounds known as monomers). This or these units are repeated at least twice and preferably at least three times.

“Film-forming polymer” means a polymer that is capable of forming, by itself or in the presence of an auxiliary film-forming agent, a macroscopically continuous film on a support, particularly on the hair, and preferably a cohesive film.

For the purposes of the present invention, “acrylic polymer” means a polymer synthesized from at least one monomer chosen from (meth)acrylic acid and/or (meth)acrylic acid ester and/or (meth)acrylic acid amide.

The unit(s) derived from the (meth)acrylic acid monomers of the polymer may optionally be in the form of salt(s), particularly of alkali metal, alkaline-earth metal or ammonium salt(s), or organic base salt(s).

The (meth)acrylic acid esters (also known as (meth)acrylates) are advantageously chosen from alkyl (meth)acrylates, in particular Ci to C30, preferably Ci to C20 and better still Ci to C10 alkyl (meth)acrylates, aryl (meth)acrylates, in particular Cf> to C10 aryl (meth)acrylates, and hydroxyalkyl (meth)acrylates, in particular C2 to Ci, hydroxyalkyl (meth)acrylates.

Among the alkyl (meth)acrylates, mention may be made of methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, 2- ethylhexyl (meth)acrylate, lauryl (meth) acrylate and cyclohexyl (meth) acrylate.

Among the hydroxy alkyl (meth)acrylates, mention may be made of hydroxyethyl acrylate, 2-hydroxypropyl acrylate, hydroxyethyl methacrylate and 2- hydroxypropyl methacrylate. Among the aryl (meth)acrylates, mention may be made of benzyl acrylate and phenyl acrylate.

The (meth)acrylic acid esters that are particularly preferred are alkyl, preferably Ci to C30, more preferentially Ci to C20, even better still Ci to C10, and even more particularly Ci to C4 alkyl (meth)acrylates.

According to the present invention, the alkyl group of the esters may be fluorinated, or even perfluorinated, i.e. some or all of the hydrogen atoms of the alkyl group are substituted with fluorine atoms.

As (meth)acrylic acid amides, examples that may be mentioned include (meth)acrylamides and also N-alkyl(meth)acrylamides, in particular N-(C2 to C12 alkyl)(meth)acrylamides. Among the N-alkyl(meth)acrylamides, mention may be made of N-ethylacrylamide, N-t-butylacrylamide, N-t-octylacrylamide and N- undecy lacry lamide .

The acrylic polymer according to the invention may be a homopolymer or a copolymer, advantageously a copolymer, even better still a copolymer of (meth)acrylic acid and of (meth)acrylic acid esters.

Preferably, the acrylic polymer(s) according to the invention comprise one or more units derived from the following monomers: a) (meth) acrylic acid; and b) Ci to C30, more preferentially Ci to C20, better still Ci to C10, and even more particularly Ci to C4, alkyl (meth)acrylate.

Preferably, the aqueous dispersion of acrylic polymer particles does not comprise any surfactant.

“Surfactant” means any agent that is capable of modifying the surface tension between two surfaces.

Among the acrylic polymers according to the invention, mention may be made of copolymers of (meth)acrylic acid and of methyl or ethyl (meth)acrylate, in particular copolymers of methacrylic acid and of ethyl acrylate such as the compound sold under the trade name Luvimer MAE by the company BASF, or the compound Polyacrylate - 2 Crosspolymer sold under the trade name Fixate Superhold Polymer by the company Eubrizol, or the compound Acrylate Copolymer sold under the trade name Daitosol 3000 VP3 by the company Daito Kasei Kogyo, or the compound Acrylate Polymer sold under the trade name Daitosol 3000 SEPN-PE1 by the company Daito Kasei Kogyo.

The acrylic polymer may optionally comprise one or more additional monomers, other than the (meth)acrylic acid and/or (meth)acrylic acid ester and/or (meth)acrylic acid amide monomers. By way of additional monomer, mention will be made, for example, of styrene monomers, in particular styrene and a-methylstyrene, and preferably styrene.

In particular, the acrylic polymer may be a styrene/(meth)acrylate copolymer and particularly a polymer chosen from copolymers resulting from the polymerization of at least one styrene monomer and at least one Ci to C20, preferably Ci to C10, alkyl (meth)acrylate monomer.

The Ci to C10 alkyl (meth) acrylate monomer may be chosen from methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hexyl acrylate, octyl acrylate and 2-ethylhexyl acrylate.

As acrylic polymer, mention may be made of the styrene/(meth)acrylate copolymers sold under the name Joncryl 77 by the company BASF, under the name Yodosol GH41F by the company Akzo Nobel and under the name Syntran 5760 CG by the company Interpolymer.

Preferably, composition C comprises at least one aqueous dispersion of acrylic polymer particles.

More preferentially, composition C comprises at least one aqueous dispersion of acrylic polymer particles comprising one or more units derived from the following monomers: a) (meth) acrylic acid; and b) Ci to C30, more preferentially Ci to C20, better still Ci to C10, and even more particularly Ci to C4, alkyl (meth) acrylate.

Preferably, the aqueous dispersion of acrylic polymer particles has an acrylic polymer (or active material, or dry matter) content, on the basis of the weight of the dispersion, of from 20 to 60% by weight, more preferentially from 22 to 55% by weight and better still from 25 to 50% by weight.

Silicone acrylic copolymer

According to a particular embodiment, the silicone compound(s) comprising at least one carboxylic group are chosen from silicone acrylic copolymers.

Thus, according to a particular embodiment, the compound(s) having at least one carboxylic function are chosen from silicone acrylic copolymers.

Preferably, said silicone acrylic copolymers comprise:

- at least one acrylic, methacrylic or crotonic unit; and

- at least one poly dimethylsiloxane (PDMS) unit.

For the purposes of the present invention, "poly dimethylsiloxanes" (also known, in abbreviation, as PDMSs) means, in accordance with what is generally accepted, any organosilicon polymer or oligomer having a linear structure, of variable molecular weight, obtained by polymerization and/or polycondensation of suitably functionalized silanes, and constituted essentially of a repetition of main units in which the silicon atoms are connected together by oxygen atoms (siloxane -Si-O-Si- bond), comprising methyl radicals directly bonded via a carbon atom to said silicon atoms.

The PDMS chains that may be used to obtain the copolymer used according to the invention include at least one polymerizable radical group, preferably located on at least one of the ends of the chain, i.e. the PDMS may have, for example, a polymerizable radical group on each of the two ends of the chain or one polymerizable radical group on one end of the chain and one trimethylsilyl end group on the other end of the chain.

The term “polymerizable radical group" means a radical capable of polymerizing with other polymerizable radical groups or monomers. Preferably, the poly dimethylsiloxane unit comprises at least one polymerizable radical group.

Preferably, the polymerizable radical group comprises at least one vinyl group.

Preferably, the polydimethylsiloxane (PDMS) unit comprises at least one polymerizable radical group comprising at least one vinyl group, preferably at least two polymerizable radical groups comprising at least one vinyl group, preferably located on at least one of the ends of the chain.

As indicated previously, said silicone acrylic copolymer(s) preferably comprise at least one acrylic, methacrylic or crotonic unit, i.e. at least one unit comprising a carboxylic group.

“Carboxylic group” means a COOH or COO- functional group, it being possible for the counterion of the COO- group to be chosen from alkali metals, alkaline-earth metals and quaternary ammoniums.

Preferably, said silicone acrylic copolymers comprise:

- at least one acrylic, methacrylic or crotonic unit, and at least one acrylic ester, methacrylic ester or vinyl ester unit; and

- at least one poly dimethylsiloxane (PDMS) unit.

More preferentially, the composition comprises one or more silicone acrylic copolymers comprising:

- at least one crotonic unit and at least one unit chosen from an alkyl crotonate unit, the alkyl radical being a linear or branched saturated radical containing from 1 to 20 carbon atoms; a vinyl acetate unit; a vinyl alkyl ester unit, the alkyl radical being a linear or branched saturated radical containing from 2 to 20 carbon atoms; and mixtures thereof; and

- at least one poly dimethylsiloxane (PDMS) unit. “crotonic unit” means a unit derived from a crotonic acid monomer or a salt thereof.

“alkyl crotonate unit” means a unit derived from a crotonic acid ester monomer, having a linear or branched saturated alkyl radical containing from 1 to 20 carbon atoms.

“vinyl alkyl ester unit” means a unit derived from a vinyl ester monomer, having a linear or branched saturated alkyl radical containing from 2 to 20 carbon atoms.

“vinyl acetate unit” means a unit derived from a vinyl acetate monomer.

According to a preferred embodiment, said silicone acrylic copolymer(s) comprise:

- at least one crotonic unit, at least one vinyl acetate unit and at least one vinyl alkyl ester unit, the alkyl radical being a linear or branched saturated radical containing from 2 to 20 carbon atoms, preferably from 2 to 18 carbon atoms, and

- at least one poly dimethylsiloxane (PDMS) unit, preferably including at least one polymerizable radical group comprising at least one vinyl group.

According to a particularly preferred embodiment, said silicone acrylic copolymer(s) comprise:

- at least one crotonic unit, at least one vinyl acetate unit and at least one vinyl alkyl ester unit, the alkyl radical being a linear or branched saturated radical containing from 6 to 16 carbon atoms, and

- at least one poly dimethylsiloxane (PDMS) unit comprising at least one polymerizable radical group comprising at least one vinyl group.

More preferentially, the composition comprises one or more silicone acrylic copolymers comprising:

- at least one crotonic unit, at least one vinyl acetate unit and at least one vinyl alkyl ester unit, the alkyl radical being a linear or branched saturated radical containing from 2 to 20 carbon atoms, preferably from 2 to 18 carbon atoms, and

- at least one poly dimethylsiloxane (PDMS) unit comprising at least one polymerizable radical group comprising at least one vinyl group.

Even more preferentially, the composition comprises one or more silicone acrylic copolymers comprising:

- at least one crotonic unit, at least one vinyl acetate unit and at least one vinyl alkyl ester unit, the alkyl radical being a linear or branched saturated radical containing from 6 to 16 carbon atoms, and

- at least one poly dimethylsiloxane (PDMS) unit including at least one polymerizable radical group comprising at least one vinyl group. Among the silicone acrylic copolymers which may be used in the context of the invention, mention may be made of the compound sold by the company Wacker Chemie AG under the trade name Belsil® Pl 101, having the INCI name Crotonic Acid/Vinyl C8-12 Isoalkyl Esters/VA/Bis-Vinyldimethicone Crosspolymer.

The total amount of the compound(s) having at least one carboxylic function preferably ranges from 0.1 to 30% by weight, more preferentially from 0.5 to 20% by weight, even better still from 1 to 15% by weight, and even more preferentially from 2 to 10% by weight relative to the total weight of composition C.

The total amount of the aqueous dispersion(s) of particles of polymer(s) chosen from polyurethanes, acrylic polymers, and mixtures thereof preferably ranges from 0.1 to 40% by weight, more preferentially from 0.5 to 30% by weight, even better still from 1 to 25% by weight, and even more preferentially from 2 to 20% by weight relative to the total weight of composition C.

According to a particular embodiment, the total amount of the aqueous dispersion(s) of particles of acrylic polymer(s) preferably ranges from 0.1% to 40% by weight, more preferentially from 0.5% to 30% by weight, even better still from 1% to 25% by weight, and even more preferentially from 2% to 20% by weight relative to the total weight of composition C.

Advantageously, the total amount of silicone acrylic copolymer(s) ranges from 0.1 to 30% by weight, more preferentially from 0.5 to 20% by weight, even better still from 1 to 15% by weight, and even more preferentially from 2 to 10% by weight relative to the total weight of composition C.

Colouring agent comprising aluminium

Composition C used in the context of the process according to the invention comprises at least one colouring agent comprising aluminium other than the colouring agents comprising at least one aluminosilicate.

Preferably, the colouring agent(s) comprising aluminium according to the invention is (are) chosen from pigments comprising aluminium other than the pigments comprising at least one aluminosilicate.

The term "pigment" means a pigment that gives colour to keratinous materials. Their solubility in water at 25 °C and at atmospheric pressure (760 mmHg) is less than 0.05% by weight, and preferably less than 0.01%.

The pigments comprising aluminium according to the invention may comprise a substrate and optionally one or more layers that may be positioned on the substrate.

The substrate may be chosen from aluminium and aluminium oxides. In particular, the substrate may be chosen from lamellar aluminium flakes and lamellar aluminium oxide flakes.

The substrate may be passivated, for example by anodization.

The substrate may be coated with one or more layers.

Preferably, the substrate is coated with a layer B.

A layer A may be present between the substrate and the layer B.

A layer C positioned on the layer B may also be present.

The layers A, B and C may be made of materials that can be applied in the form of films and permanently to the substrate.

The layers A, B and C may partially, or even completely, cover the surface of the substrate.

For example, the upper face and/or the lower face of the surface of the substrate may be completely covered by at least one of layers A, B and C, whilst the side faces of the surface of the substrate are not covered.

The layer A may be made of at least one material chosen from metal oxides and/or hydrates of metal oxides with a low refractive index.

For the purposes of the present invention, a material "with a low refractive index" is understood to mean a material having a refractive index less than or equal to 1.8, preferably less than or equal to 1.6.

Advantageously, the layer A comprises at least 95% by weight, preferably at least 99% by weight, of metal oxides and/or of hydrates of metal oxides with a low refractive index relative to the total weight of the material constituting the layer A.

The metal oxides and/or hydrates of metal oxides with a low refractive index may be chosen from silicon (di)oxide, hydrated silicon oxide, aluminium oxide, hydrated aluminium oxide, boron oxide, germanium oxide, manganese oxide, magnesium oxide and mixtures thereof, preferably from silicon dioxide.

The layer A may have a thickness ranging from 1 to 100 nm, preferably ranging from 5 to 50 nm, more preferentially from 5 to 20 nm.

Advantageously, the layer B is constituted of at least one metal oxide with a high refractive index.

For the purposes of the present invention, a material "with a high refractive index" is understood to mean a material having a refractive index greater than or equal to 1.9, preferably greater than or equal to 2.0, more preferentially greater than or equal to 2.4.

The metal oxides with a high refractive index may be chosen from the metal oxides that absorb light, such as ferric oxide, cobalt (II) oxide, chromium (III) oxide, titanium (III) oxide, vanadium (V) oxide, and mixtures thereof. The metal oxides with a high refractive index may also be chosen from noncoloured oxides, such as titanium dioxide and/or zirconium oxide.

The layer B may have a thickness of at least 50 nm, preferably ranging from 50 to 400 nm, more preferentially from 50 to 300 nm.

Advantageously, the layer C may be made of at least one material chosen from metal oxides and/or hydrates of metal oxides.

The metal oxides and/or hydrates of metal oxides may be chosen from silicon (di)oxide, hydrated silicon oxide, aluminium oxide, hydrated aluminium oxide, zinc oxide, tin oxide, titanium dioxide, zirconium oxide, iron (III) oxide, chromium oxide and mixtures thereof, preferably from silicon dioxide.

The layer C may have a thickness ranging from 10 to 500 nm, preferably ranging from 50 to 300 nm.

Preferably, the substrate is coated with a layer B only.

Preferably, the substrate is coated with a layer comprising at least one metal oxide with a high refractive index, more preferentially chosen from the metal oxides that absorb light, such as ferric oxide, cobalt (II) oxide, chromium (III) oxide, titanium (III) oxide, vanadium (V) oxide, and mixtures thereof.

Advantageously, the colouring agent comprising aluminium according to the invention has a thickness ranging from 70 to 500 nm, preferably ranging from 100 to 400 nm.

According to a preferred embodiment, organic compounds such as silanes may be added to the outermost layer, i.e. to layer A, or to layer B or to layer C.

Preferably, the pigment(s) comprising aluminium according to the invention is (are) coated with a layer comprising organic compounds such as silanes.

Preferably, the organic compounds may be chosen from methacryloxypropenyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3- acryloxypropyltrimethoxysilane, 2-acryloxyethyltrimethoxysilane, 3 -methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, 2-methacryloxy- ethyltriethoxysilane, 2-acryloxyethyltriethoxysilane, 3- methoxypropyl- tris(methoxyacryloxypropyl)silane, 3-methacryloxypropyltrimethoxysilane, methacryloxypropyltris(propoxy)silane, 3-methacryloxypropyl(butoxy)silane, 3- acryloxypropyltris(methoxyethoxy)silane, 3-acryloxypropyltris(butoxyethoxy)silane, 3-acryloxypropyltris(butoxy)silane, vinyltrimethoxysilane, vinyltriethoxysilane, vinylethyldichlorosilane, vinylmethyldiacetoxysilane, vinylmethyldichlorosilane, vinylmethyldiethoxysilane, vinyltriacetoxy silane, vinyltrichlorosilane, phenylvinyldiethoxy silane or phenylallyldichlorosilane. As an example of a colouring agent comprising aluminium according to the invention, mention may be made of the product sold under the trade name STARBRITE REVEAL AQ 4172PA sold by the company Siberline.

The pigments may be dispersed in the composition by means of a dispersant.

The dispersant serves to protect the dispersed particles against agglomeration or flocculation thereof. This dispersant may be a surfactant, an oligomer, a polymer or a mixture of several thereof, bearing one or more functionalities with strong affinity for the surface of the particles to be dispersed. In particular, they may become physically or chemically attached to the surface of the pigments. These dispersants also contain at least one functional group that is compatible with or soluble in the continuous medium. In particular, esters of 12-hydroxystearic acid in particular and of C8 to C20 fatty acid and of polyols such as glycerol or diglycerol are used, such as poly(12-hydroxystearic acid) stearate with a molecular weight of approximately 750 g/mol, such as the product sold under the name Solsperse 21 000 by the company Avecia, polyglyceryl-2 dipoly hydroxy stearate (CTFA name) sold under the reference Dehymyls PGPH by the company Henkel, or else polyhydroxystearic acid such as the product sold under the reference Arlacel P100 by the company Uniqema, and mixtures thereof.

As other dispersants that may be used in the compositions of the invention, mention may be made of quaternary ammonium derivatives of polycondensed fatty acids, for instance Solsperse 17 000 sold by the company Avecia, and polydimethylsiloxane/oxypropylene mixtures such as those sold by the company Dow Coming under the references DC2-5185 and DC2-5225 C.

According to a particular embodiment of the invention, the dispersant is present with organic or inorganic pigments in submicron- sized particulate form.

“ Submicron- sized” or “ submicronic” means pigments having a particle size that has been micronized by a micronization method and having a mean particle size of less than a micrometre (pm), in particular between 0.1 and 0.9 pm, and preferably between 0.2 and 0.6 pm.

According to one embodiment, the dispersant and the pigment(s) are present in a (dispersantpigment) amount, according to a weight ratio, of between 1: 4 and 4: 1, particularly between 1.5: 3.5 and 3.5: 1 or better still between 1.75: 3 and 3: 1.

The dispersant(s) may therefore have a silicone backbone, such as silicone polyether, and dispersants of aminosilicone type. Among the suitable dispersants that may be mentioned are: - aminosilicones, i.e. silicones comprising one or more amino groups such as those sold under the names and references: BYK LPX 21879 by BYK, GP-4, GP-6, GP-344, GP-851, GP-965, GP-967 and GP-988-1, sold by Genesee Polymers,

- silicone acrylates such as Tego® RC 902, Tego® RC 922, Tego® RC 1041, and Tego® RC 1043, sold by Evonik,

- polydimethylsiloxane (PDMS) silicones bearing carboxylic groups such as X-22162 and X-22370 by Shin-Etsu, epoxy silicones such as GP-29, GP-32, GP-502, GP-504, GP-514, GP-607, GP-682, and GP-695 by Genesee Polymers, or Tego® RC 1401, Tego® RC 1403, Tego® RC 1412 by Evonik.

According to one particular embodiment, the dispersant(s) are of aminosilicone type and are cationic.

The colouring agent(s) comprising aluminium according to the invention may be present in a total amount ranging from 0.001 to 20% by weight, preferably from 0.005 to 15% by weight relative to the total weight of composition C. Preferably, the colouring agent(s) comprising aluminium according to the invention is (are) chosen from pigments comprising aluminium other than pigments comprising at least one aluminosilicate.

The pigment(s) comprising aluminium other than pigments comprising at least one aluminosilicate may be present in a total amount ranging from 0.05 to 20% by weight, preferably from 0.1 to 15% by weight, better still from 0.5 to 10% by weight relative to the total weight of composition C.

The composition C used within the context of the process according to the invention may further comprise one or more pigments other than the pigments comprising aluminium according to the invention.

Said pigments that may be used are particularly chosen from the organic and/or mineral pigments known in the art, particularly those described in Kirk- Othmer’s Encyclopedia of Chemical Technology and in Ullmann’s Encyclopedia of Industrial Chemistry.

They may be natural, of natural origin, or non-natural.

These pigments may be in pigment powder or paste form. They may be coated or uncoated.

Said pigments may be chosen, for example, from mineral pigments, organic pigments, lakes, pigments with special effects such as nacres or glitter flakes, and mixtures thereof.

Said pigment may be a mineral pigment. “Mineral pigment” means any pigment that satisfies the definition in Ullmann’s encyclopedia in the chapter on inorganic pigments. Among the mineral pigments that are useful in the present invention, mention may be made of iron oxides, chromium oxides, manganese violet, ultramarine blue, chromium hydrate, ferric blue and titanium oxide.

Said pigment may be an organic pigment. “Organic pigment” means any pigment that satisfies the definition in Ullmann’s Encyclopedia in the chapter on organic pigments.

The organic pigment may particularly be chosen from nitroso, nitro, azo, xanthene, pyrene, quinoline, anthraquinone, triphenylmethane, fluorane, phthalocyanine, metal-complex, isoindolinone, isoindoline, quinacridone, perinone, perylene, diketopyrrolopyrrole, indigo, thioindigo, dioxazine, triphenylmethane and quinophthalone compounds.

In particular, the white or coloured organic pigments may be chosen from carmine, carbon black, aniline black, azo yellow, quinacridone, phthalocyanine blue, the blue pigments codified in the Colour Index under the references CI 42090, 69800, 69825, 74100, 74160, the yellow pigments codified in the Colour Index under the references CI 11680, 11710, 19140, 20040, 21100, 21108, 47000, 47005, the green pigments codified in the Colour Index under the references CI 61565, 61570, 74260, the orange pigments codified in the Colour Index under the references CI 11725, 45370, 71105, the red pigments codified in the Colour Index under the references CI 12085, 12120, 12370, 12420, 12490, 14700, 15525, 15580, 15620, 15630, 15800, 15850, 15865, 15880, 26100, 45380, 45410, 58000, 73360, 73915, 75470, the pigments obtained by oxidative polymerization of indole or phenol derivatives as described in patent FR 2 679 771.

Examples that may also be mentioned include pigment pastes of organic pigments, such as the products sold by the company Hoechst under the names:

- Cosmenyl Yellow 10G: Yellow 3 pigment (CI 11710);

- Cosmenyl Yellow G: Yellow 1 pigment (CI 11680);

- Cosmenyl Orange GR: Orange 43 pigment (CI 71105);

- Cosmenyl Red R: Red 4 pigment (CI 12085);

- Cosmenyl Carmine FB: Red 5 pigment (CI 12490);

- Cosmenyl Violet RL: Violet 23 pigment (CI 51319);

- Cosmenyl Blue A2R: Blue 15.1 pigment (CI 74160);

- Cosmenyl Green GG: Green 7 pigment (CI 74260);

- Cosmenyl Black R: Black 7 pigment (CI 77266).

Said pigments may also be in the form of composite pigments, as described in patent EP 1 184 426. These composite pigments may particularly be composed of particles including an inorganic core, at least one binder for attaching the organic pigments to the core, and at least one organic pigment which at least partially covers the core.

The organic pigment may also be a lake. “Lake” means dyes adsorbed onto insoluble particles, the assembly thus obtained remaining insoluble during use.

The inorganic substrates onto which the dyes are adsorbed are, for example, silica, calcium sodium borosilicate or calcium aluminium borosilicate.

Among the dyes, mention may be made of carminic acid. Mention may also be made of the dyes known under the following names: D & C Red 21 (CI 45 380), D & C Orange 5 (CI 45 370), D & C Red 27 (CI 45 410), D & C Orange 10 (CI 45 425), D & C Red 3 (CI 45 430), D & C Red 4 (CI 15 510), D & C Red 33 (CI 17 200), D & C Yellow 5 (CI 19 140), D & C Yellow 6 (CI 15 985), D & C Green (CI 61 570), D & C Yellow 1 O (CI 77 002), D & C Green 3 (CI 42 053), D & C Blue 1 (CI 42 090).

An example of a lake that may be mentioned is the product known under the following name: D&C Red 7 (CI 15 850:1).

Said pigment may also be a pigment with special effects. “Pigments with special effects” means pigments that generally create a coloured appearance (characterized by a certain shade, a certain vivacity and a certain level of luminance) that is non-uniform and that changes based on the conditions of observation (light, temperature, angles of observation, etc.). They thereby differ from coloured pigments, which afford a standard uniform opaque, semi-transparent or transparent shade.

Several types of pigments with special effects exist: those with a low refractive index, such as fluorescent or photochromic pigments, and those with a higher refractive index, such as nacres, interference pigments or glitter flakes.

Examples of pigments with special effects that may be mentioned include nacreous pigments such as mica coated with titanium or with bismuth oxychloride, coloured nacreous pigments such as mica covered with titanium and with iron oxides, mica covered with iron oxide, mica covered with titanium and particularly with ferric blue or with chromium oxide, mica covered with titanium and with an organic pigment as defined previously, and also nacreous pigments based on bismuth oxychloride. Nacreous pigments that may be mentioned include the nacres Cellini sold by BASF (mica-TiO2-lake), Prestige sold by Eckart (mica-TiO2), Prestige Bronze sold by Eckart (mica-Fe2O3) and Colorona sold by Merck (mica-TiO2-Fe2O3).

Mention may also be made of the gold-coloured nacres sold particularly by the company BASF 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 particularly by the company Merck under the name Bronze fine (17384) (Colorona) and Bronze (17353) (Colorona) and by the company BASF under the name Super bronze (Cloisonne); the orange nacres sold particularly by the company BASF 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 particularly by the company BASF under the name Nu-antique copper 340XB (Cloisonne) and Brown CL4509 (Chromalite); the nacres with a copper tint sold particularly by the company BASF under the name Copper 340A (Timica); the nacres with a red tint sold particularly by the company Merck under the name Sienna fine (17386) (Colorona); the nacres with a yellow tint sold particularly by the company BASF under the name Yellow (4502) (Chromalite); the red nacres with a gold tint sold particularly by the company BASF under the name Sunstone G012 (Gemtone); the pink nacres sold particularly by the company BASF under the name Tan opale G005 (Gemtone); the black nacres with a gold tint sold particularly by the company BASF under the name Nu antique bronze 240 AB (Timica), the blue nacres sold particularly by the company Merck under the name Matte blue (17433) (Microna), the white nacres with a silvery tint sold particularly by the company Merck under the name Xirona Silver, and the golden-green pink-orange nacres sold particularly by the company Merck under the name Indian summer (Xirona), and mixtures thereof.

Still as examples of nacres, mention may also be made of particles including a borosilicate substrate coated with titanium oxide.

Particles comprising a glass substrate coated with titanium oxide are particularly sold under the name Metashine MC1080RY by the company Toyal.

Finally, examples of nacres that may also be mentioned include polyethylene terephthalate glitter flakes, particularly those sold by the company Meadowbrook Inventions under the name Silver IP 0.004X0.004 (silver glitter flakes). It is also possible to envisage multilayer pigments based on synthetic substrates, such as silica, calcium sodium borosilicate or calcium aluminium borosilicate.

The pigments with special effects may also be chosen from reflective particles, i.e. particularly from particles whose size, structure, particularly the thickness of the layer(s) of which they are made and their physical and chemical nature, and surface state, allow them to reflect incident light. This reflection may, where appropriate, have an intensity sufficient to create, at the surface of the composition or of the mixture, when it is applied to the support to be made up, highlight points that are visible to the naked eye, i.e. more luminous points that contrast with their environment by appearing to sparkle.

The reflective particles may be selected so as not to significantly alter the colouring effect generated by the colouring agents with which they are combined, and more particularly so as to optimize this effect in terms of colour rendition. They may more particularly have a yellow, pink, red, bronze, orangey, brown, gold and/or coppery colour or tint.

These particles may have varied forms and may particularly be in platelet or globular form, in particular in spherical form.

The reflective particles, regardless of their form, may or may not have a multilayer structure and, in the case of a multilayer structure, may have, for example, at least one layer of uniform thickness, particularly of a reflective material.

When the reflective particles do not have a multilayer structure, they may be composed, for example, of metal oxides, with the exception of aluminium oxides, particularly titanium or iron oxides obtained synthetically.

When the reflective particles have a multilayer structure, they may include, for example, a natural or synthetic substrate, particularly a synthetic substrate at least partially coated with at least one layer of a reflective material, particularly of at least one metal or metallic material. The substrate may be made of one or more organic and/or inorganic materials.

More particularly, it may be chosen from glasses, ceramics, graphite, metal oxides, with the exception of aluminium oxides, silicas, silicates, particularly aluminosilicates and borosilicates, and synthetic mica, and mixtures thereof, this list not being limiting.

The reflective material may include a layer of metal or of a metallic material.

Reflective particles are particularly described in JP-A-09188830, JP-A- 10158450, JP-A-10158541, JP-A-07258460 and JP-A-05017710.

Again as an example of reflective particles including a mineral substrate coated with a layer of metal, mention may also be made of particles including a silver- coated borosilicate substrate.

Particles with 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 with a glass substrate coated with a nickel/chromium/molybdenum alloy are sold under the names Crystal Star GF 550 and GF 2525 by this same company.

Use may also be made of particles comprising a metal substrate, such as silver, iron, chromium, nickel, molybdenum, gold, copper, zinc, tin, magnesium, steel, bronze or titanium, said substrate being coated with at least one layer of at least one metal oxide, such as titanium oxide, iron oxide, cerium oxide, chromium oxide, silicon oxides and mixtures thereof.

Examples that may be mentioned include bronze powder or copper powder coated with SiO2 sold under the name Visionaire by the company Eckart. Mention may also be made of interference pigments which are not attached to a substrate, such as liquid crystals (Helicones HC from Wacker) or interference holographic glitter flakes (Geometric Pigments or Spectra f/x from Spectratek). Special effect pigments also comprise fluorescent pigments, whether these are substances that are fluorescent in daylight or that produce an ultraviolet fluorescence, phosphorescent pigments, photochromic pigments, thermochromic pigments and quantum dots, sold, for example, by the company Quantum Dots Corporation.

The variety of pigments that may be used in the present invention makes it possible to obtain a wide range of colours, and also particular optical effects such as metallic effects or interference effects.

The size of the pigment used in the composition according to the present invention is generally between 10 nm and 200 pm, preferably between 20 nm and 80 pm and more preferentially between 30 nm and 50 pm.

The pigments may be dispersed in the composition by means of a dispersant as described above.

Moreover, said pigments may be surface-treated with an organic agent.

Thus, the pigments surface-treated beforehand that are useful in the context of the invention are pigments which have been completely or partially subjected to a surface treatment of chemical, electronic, electrochemical, mechanochemical or mechanical nature with an organic agent, such as those described particularly in Cosmetics and Toiletries, February 1990, Vol. 105, pages 53-64, before being dispersed in the composition in accordance with the invention. These organic agents may be chosen, for example, from waxes, for example carnauba wax and beeswax; fatty acids, fatty alcohols and derivatives thereof, such as stearic acid, hydroxy stearic acid, stearyl alcohol, hydroxystearyl alcohol and lauric acid and derivatives thereof; anionic surfactants; lecithins; sodium, potassium, magnesium, iron, titanium, zinc or aluminium salts of fatty acids, for example aluminium stearate or laurate; metal alkoxides; polyethylene; (meth)acrylic polymers, for example polymethyl methacrylates; polymers and copolymers containing acrylate units; alkanolamines; silicone compounds, for example silicones, particularly poly dimethylsiloxanes; organofluorine compounds, for example perfluoroalkyl ethers; fluorosilicone compounds.

The surface-treated pigments that are useful in the composition may also have been treated with a mixture of these compounds and/or may have undergone several surface treatments. The surface-treated pigments that are useful in the context of the present invention may be prepared according to surface-treatment techniques that are well known to those skilled in the art, or may be commercially available as is.

Preferably, the surface-treated pigments are coated with an organic layer.

The organic agent with which the pigments are treated may be deposited on the pigments by evaporation of solvent, chemical reaction between the molecules of the surface agent or creation of a covalent bond between the surface agent and the pigments.

The surface treatment may thus be performed, for example, by chemical reaction of a surface agent with the surface of the pigments and creation of a covalent bond between the surface agent and the pigments or the fillers. This method is particularly described in patent US 4 578 266.

An organic agent covalently bonded to the pigments will preferably be used.

The agent for the surface treatment may represent from 0.1 to 50% by weight of the total weight of the surface-treated pigment, preferably from 0.5 to 30% by weight and even more preferentially from 1 to 20% by weight of the total weight of the surface-treated pigment.

Preferably, the surface treatments of the pigments are chosen from the following treatments:

- a PEG- silicone treatment, for instance the AQ surface treatment sold by LCW;

- a methicone treatment, for instance the SI surface treatment sold by LCW;

- a dimethicone treatment, for instance the Covasil 3.05 surface treatment sold by LCW;

- a dimethicone/trimethylsiloxysilicate treatment, for instance the Covasil 4.05 surface treatment sold by LCW;

- a magnesium myristate treatment, for instance the MM surface treatment sold by LCW;

- an aluminium dimyristate treatment, for instance the MI surface treatment sold by Miyoshi;

- a perfluoropolymethyl isopropyl ether treatment, for instance the FHC surface treatment sold by LCW;

- an isostearyl sebacate treatment, for instance the HS surface treatment sold by Miyoshi;

- a perfluoroalkyl phosphate treatment, for instance the PF surface treatment sold by Daito; - an acrylate/dimethicone copolymer and perfluoroalkyl phosphate treatment, for instance the FSA surface treatment sold by Daito;

- a polymethylhydrogenosiloxane/perfluoroalkyl phosphate treatment, for instance the FS01 surface treatment sold by Daito;

- an acrylate/dimethicone copolymer treatment, for instance the ASC surface treatment sold by Daito;

- an isopropyl titanium triisostearate treatment, for instance the ITT surface treatment sold by Daito;

- an acrylate copolymer treatment, for instance the APD surface treatment sold by Daito;

- a perfluoroalkyl phosphate/isopropyl titanium triisostearate treatment, for instance the PF + ITT surface treatment sold by Daito.

Preferably, said pigments may be chosen from mineral, mixed mineral- organic or organic pigments.

In one variant of the invention, said pigments are organic pigments, preferentially organic pigments surface-treated with an organic agent chosen from silicone compounds. In another variant of the invention, said pigments are mineral pigments.

According to a particular embodiment, the composition C used in the context of the process according to the invention comprises at least one pigment comprising aluminium other than the pigments comprising at least one aluminosilicate and at least one pigment other than the pigments comprising aluminium according to the invention.

Direct dye

Composition C used in the context of the process according to the invention may also comprise one or more direct dye(s) other than the colouring agents comprising aluminium previously described.

"Direct dye” means natural and/or synthetic dyes, other than oxidation dyes. These are dyes which will spread superficially over the fibre.

They may be ionic or non-ionic, preferably cationic or non-ionic.

Examples of suitable direct dyes that may be mentioned include azo direct dyes; (poly)methine dyes such as cyanines, hemicyanines and styryls; carbonyl dyes; azine dyes; nitro(hetero)aryl dyes; tri(hetero)arylmethane dyes; porphyrin dyes; phthalocyanine dyes and natural direct dyes, alone or in the form of mixtures.

The direct dyes are preferably cationic direct dyes. Mention may be made of the hydrazono cationic dyes of formulae (XIII) and (XIV) and the azo cationic dyes (XV) and (XVI) below: in which formulae (XIII) to (XVI):

- Het+ represents a cationic heteroaryl radical, preferentially bearing an endocyclic cationic charge, such as imidazolium, indolium or pyridinium, which is optionally substituted, preferentially with at least one (Ci-Cs)alkyl group such as methyl;

- Ar+ represents an aryl radical, such as phenyl or naphthyl, bearing an exocyclic cationic charge, preferentially ammonium, particularly tri(Ci- C8)alkylammonium, such as trimethylammonium;

- Ar represents an aryl group, particularly phenyl, which is optionally substituted, preferentially with one or more electron-donating groups such as i) optionally substituted (Ci-Cs)alkyl, ii) optionally substituted (Ci-Cs)alkoxy, iii) (di)(Ci-C8)(alkyl)amino optionally substituted on the alkyl group(s) with a hydroxyl group, iv) aryl(Ci-C8)alkylamino, v) optionally substituted N-(Ci-Cs)alkyl-N- aryl(Ci-C8)alkylamino or alternatively Ar represents a julolidine group;

- Ar’ ’ represents an optionally substituted (hetero)aryl group, such as phenyl or pyrazolyl, which are optionally substituted, preferentially with one or more (Ci- Cs)alkyl, hydroxyl, (di)(Ci-C8)(alkyl)amino, (Ci-Cs)alkoxy or phenyl groups;

- Ra and Rb, which are identical or different, represent a hydrogen atom or a (Ci-Cs)alkyl group, which is optionally substituted, preferentially with a hydroxyl group; or else the substituent Ra with a substituent of Het+ and/or Rb with a substituent of Ar form, together with the atoms that bear them, a (hetero)cycloalkyl; in particular, Ra and Rb represent a hydrogen atom or a (Ci-C4)alkyl group optionally substituted with a hydroxyl group;

- Q- represents an organic or mineral anionic counterion, such as a halide or an alkyl sulfate.

In particular, mention may be made of the azo and hydrazono direct dyes bearing an endocyclic cationic charge of formulae (XIII) to (XVI) as defined previously; more particularly, the cationic direct dyes bearing an endocyclic cationic charge described in patent applications WO 95/15144, WO 95/01772 and EP 714 954; preferentially, the following direct dyes:

(XVIII), in which formulae (XVII) and (XVIII):

- R ¹ represents a (Ci-C4)alkyl group such as methyl;

- R ² and R ³ , which are identical or different, represent a hydrogen atom or a (Ci-C4)alkyl group, such as methyl; and

- R ⁴ represents a hydrogen atom or an electron-donating group such as optionally substituted (Ci-Cs)alkyl, optionally substituted (Ci-Cs)alkoxy, or (di)(Ci- Cs)(alkyl)amino optionally substituted on the alkyl group(s) with a hydroxyl group; in particular, R ⁴ is a hydrogen atom;

- Z represents a CH group or a nitrogen atom, preferentially CH;

- Q- is an anionic counterion as defined previously, in particular a halide, such as chloride, or an alkyl sulfate, such as methyl sulfate or mesityl.

In particular, the dyes of formulae (XVII) and (XVIII) are chosen from Basic Red 51, Basic Yellow 87 and Basic Orange 31 or derivatives thereof with Q’ being an anionic counterion as defined previously, particularly halide such as chloride, or an alkyl sulfate such as methyl sulfate or mesityl.

The direct dyes may be chosen from anionic direct dyes. The anionic direct dyes of the invention are dyes commonly referred to as “acid” direct dyes owing to their affinity for alkaline substances. “Anionic direct dye” means any direct dye including in its structure at least one CO2R or SO3R substituent with R denoting a hydrogen atom or a cation originating from a metal or an amine, or an ammonium ion. The anionic dyes may be chosen from direct nitro acid dyes, azo acid dyes, azine acid dyes, triarylmethane acid dyes, indoamine acid dyes, anthraquinone acid dyes, indigoid dyes and natural acid dyes.

As acid dyes which are useful for the invention, mention may be made of the dyes of formulae (XIX), (XIX’), (XX), (XX’), (XXI), (XXI’), (XXII), (XXII’), (XXIII), (XXIV), (XXV) and (XXVI) below: a) the diaryl anionic azo dyes of formula (XIX) or (XIX'): in which formulae (XIX) and (XIX'):

- R7, Rs, R9, R 10, R’7, R’s, R’9 and R’ 10, which are identical or different, represent a hydrogen atom or a group chosen from:

- alkyl;

- alkoxy, alkylthio;

- hydroxyl, mercapto;

- nitro, nitroso;

- R°-C(X)-X’-, R°-X’-C(X)-, R°-X’-C(X)-X”- with R° representing a hydrogen atom or an alkyl or aryl group; X, X’ and X’ ’ , which are identical or different, representing an oxygen or sulfur atom, or NR with R representing a hydrogen atom or an alkyl group;

- (O) ₂ S(O-)-, M+ with M+ representing a hydrogen atom or a cationic counterion;

- (O)CO— , M+ with M+ as defined previously;

- R”-S(O)2-, with R” representing a hydrogen atom or an alkyl group, an aryl, (di) (alkyl) amino or aryl(alkyl)amino group; preferentially a phenylamino or phenyl group;

- R”’-S(O)2-X’- with R”’ representing an optionally substituted alkyl or aryl group, X’ as defined previously;

- (di) (alkyl) amino;

- ary l(alkyl) amino optionally substituted with one or more groups chosen from i) nitro; ii) nitroso; iii) (O)2S(O-)-, M+ and iv) alkoxy with M+ as defined previously; - optionally substituted heteroaryl; preferentially a benzothiazolyl group;

- cycloalkyl, particularly cyclohexyl;

- Ar-N=N- with Ar representing an optionally substituted aryl group; preferentially a phenyl optionally substituted with one or more alkyl, (O)2S(O-)-, M+ or phenylamino groups;

- or alternatively two contiguous groups R? with Rs or Rs with R9 or R9 with Rio together form a fused benzo group A’; and R’7 with R’ s or R’ s with R’9 or R’9 with R’ 10 together form a fused benzo group B’; with A’ and B’ optionally substituted with one or more groups chosen from i) nitro; ii) nitroso; iii) (O)2S(O )-, M ⁺ ; iv) hydroxyl; v) mercapto; vi) (di)(alkyl)amino; vii) R°-C(X)-X’-; viii) R°-X’-C(X)-; ix) R°-X’-C(X)-X”-; x) Ar-N=N- and xi) optionally substituted ary l(alkyl) amino; with M ⁺ , R°, X, X’, X” and Ar as defined previously;

- W represents a sigma bond c, an oxygen or sulfur atom, or a divalent radical i) -NR- with R as defined previously, or ii) methylene -C(Ra)(Rb)- with Ra and Rb, which are identical or different, representing a hydrogen atom or an aryl group, or alternatively Ra and Rb form, together with the carbon atom that bears them, a spiro cycloalkyl; preferentially, W represents a sulfur atom or Ra and Rb together form a cyclohexyl; it being understood that formulae (XIX) and (XIX’) comprise at least one sulfonate radical (O)2S(O-)-, M+ or one carboxylate radical (O)CO— , M+ on one of the rings A, A’, B, B’ or C; preferentially sodium sulfonate.

As examples of dyes of formula (XIX), mention may be made of: Acid Red 1, Acid Red 4, Acid Red 13, Acid Red 14, Acid Red 18, Acid Red 27, Acid Red 28, Acid Red 32, Acid Red 33, Acid Red 35, Acid Red 37, Acid Red 40, Acid Red 41, Acid Red 42, Acid Red 44, Pigment Red 57, Acid Red 68, Acid Red 73, Acid Red 135, Acid Red 138, Acid Red 184, Food Red 1, Food Red 13, Acid Orange 6, Acid Orange 7, Acid Orange 10, Acid Orange 19, Acid Orange 20, Acid Orange 24, Yellow 6, Acid Yellow 9, Acid Yellow 36, Acid Yellow 199, Food Yellow 3, Acid Violet 7, Acid Violet 14, Acid Blue 113, Acid Blue 117, Acid Black 1, Acid Brown 4, Acid Brown 20, Acid Black 26, Acid Black 52, Food Black 1, Food Black 2, Food Yellow 3 or Sunset Yellow; and, as examples of dyes of formula (XIX’), mention may be made of: Acid Red 111, Acid Red 134, Acid Yellow 38; b) the pyrazolone anionic azo dyes of formulae (XX) and (XX'):

(XX’), in which formulae (XX) and (XX’):

- Rn, R12 and R13, which are identical or different, represent a hydrogen or halogen atom, an alkyl group or -(O)2S(O-), M+ with M+ as defined previously;

- R14 represents a hydrogen atom, an alkyl group or a group -C(O)O“, M ⁺ with M ⁺ as defined previously;

- R15 represents a hydrogen atom;

- Ri6 represents an oxo group, in which case R’ i6 is absent, or alternatively R15 with Ri6 together form a double bond;

- R17 and Ris, which are identical or different, represent a hydrogen atom, or a group chosen from:

- (O) ₂ S(O-)-, M+ with M+ as defined previously;

- Ar-O-S(O)2- with Ar representing an optionally substituted aryl group; preferentially a phenyl optionally substituted with one or more alkyl groups;

- R19 and R20 together form either a double bond, or a benzo group D’, which is optionally substituted;

- R’ 16, R’ 19 and R’20, which are identical or different, represent a hydrogen atom or an alkyl or hydroxyl group;

- R21 represents a hydrogen atom or an alkyl or alkoxy group;

- Ra and Rb, which are identical or different, are as defined previously; preferentially, Ra represents a hydrogen atom and Rb represents an aryl group;

- Y represents either a hydroxyl group or an oxo group; > represents a single bond when Y is an oxo group; and represents a double bond when Y represents a hydroxyl group; it being understood that formulae (XX) and (XX’) comprise at least one sulfonate radical (O)2S(O-)-, M+ or one carboxylate radical -C(O)O-, M+ on one of the rings D or E; preferentially sodium sulfonate;

As examples of dyes of formula (XX), mention may be made of: Acid Red 195, Acid Yellow 23, Acid Yellow 27, Acid Yellow 76, and, as an example of a dye of formula (XX’), mention may be made of: Acid Yellow 17; c) the anthraquinone dyes of formulae (XXI) and (XXI'):

(XXD, in which formulae (XXI) and (XXI’):

- R22, R23, R24, R25, R26 and R27, which are identical or different, represent a hydrogen or halogen atom, or a group chosen from:

- alkyl;

- hydroxyl, mercapto;

- alkoxy, alkylthio;

- optionally substituted aryloxy or arylthio, preferentially substituted with one or more groups chosen from alkyl and (O)2S(O )-, M ⁺ with M ⁺ as defined previously; - ary l(alkyl) amino optionally substituted with one or more groups chosen from alkyl and (O)2S(O-)-, M ⁺ with M ⁺ as defined previously;

- (di) (alkyl) amino;

- (di)(hydroxyalkyl)amino;

- (O) ₂ S(O-)-, M+ with M+ as defined previously;

- Z’ represents a hydrogen atom or a group NR28R29 with R28 and R29, which are identical or different, representing a hydrogen atom or a group chosen from:

- alkyl;

- polyhydroxyalkyl such as hydroxyethyl;

- aryl optionally substituted with one or more groups, particularly i) alkyl such as methyl, n-dodecyl, n-butyl; ii) (O)2S(O-)-, M ⁺ with M ⁺ as defined previously; iii) R°-C(X)-X’-, R°-X’-C(X)-, R°-X’-C(X)-X”- with R°, X, X’ and X” as defined previously, preferentially R° represents an alkyl group;

- cycloalkyl, particularly cyclohexyl;

- Z represents a group chosen from hydroxyl and NR’2sR’29 with R’28 and R’29, which are identical or different, representing the same atoms or groups as R28 and R29 as defined previously; it being understood that formulae (XXI) and (XXI’) comprise at least one sulfonate radical (O)2S(O-)-, M+ or one carboxylate radical -C(O)O-, M+; preferentially sodium sulfonate;

As examples of dyes of formula (XXI), mention may be made of: Acid Blue 25, Acid Blue 43, Acid Blue 62, Acid Blue 78, Acid Blue 129, Acid Blue 138, Acid Blue 140, Acid Blue 251, Acid Green 25, Acid Green 41, Acid Violet 42, Acid Violet 43, Mordant Red 3; EXT Violet No. 2; and, as an example of a dye of formula (XXI’), mention may be made of: Acid Black 48; d) the nitro dyes of formulae (XXII) and (XXII’):

(XXII),

(XXII’), in which formulae (XXII) and (XXII'):

- R30, R31 and R32, which are identical or different, represent a hydrogen or halogen atom, or a group chosen from:

- alkyl;

- alkoxy optionally substituted with one or more hydroxyl groups, alkylthio optionally substituted with one or more hydroxyl groups;

- hydroxyl, mercapto;

- nitro, nitroso;

- polyhaloalkyl;

- R°-C(X)-X’-, R°-X’-C(X)-, R°-X’-C(X)-X”- with R°, X, X’ and X” as defined previously;

- (O) ₂ S(O-)-, M+ with M+ as defined previously;

- (O)CO— , M+ with M+ as defined previously;

- (di) (alkyl) amino;

- (di)(hydroxyalkyl)amino;

- heterocycloalkyl such as piperidino, piperazino or morpholino; in particular, R30, R31 and R32 represent a hydrogen atom;

- Rc and Rd, which are identical or different, represent a hydrogen atom or an alkyl group;

- W is as defined previously; W particularly represents an -NH- group;

- ALK represents a linear or branched divalent Ci-Ce alkylene group; in particular, ALK represents a -CH2-CH2- group;

- n is 1 or 2;

- p represents an integer inclusively between 1 and 5;

- q represents an integer inclusively between 1 and 4;

- u is 0 or 1 ;

- when n is 1, J represents a nitro or nitroso group; particularly nitro;

- when n is 2, J represents an oxygen or sulfur atom, or a divalent radical - S(O) _m - with m representing an integer 1 or 2; preferentially, J represents an -SO2- radical;

- M’ represents a hydrogen atom or a cationic counterion; , which may be present or absent, represents a benzo group optionally substituted with one or more groups R30 as defined previously; it being understood that formulae (XXII) and (XXII’) comprise at least one sulfonate radical (O)2S(O-)-, M+ or one carboxylate radical -C(O)O-, M+; preferentially sodium sulfonate.

As examples of dyes of formula (XXII), mention may be made of: Acid Brown 13 and Acid Orange 3; as examples of dyes of formula (XXII'), mention may be made of: Acid Yellow 1, the sodium salt of 2,4-dinitro-l-naphthol-7-sulfonic acid, 2-piperidino-5-nitrobenzenesulfonic acid, 2-(4’-N,N-(2”-hydroxyethyl)amino-2’- nitro)anilineethanesulfonic acid, 4-P-hydroxyethylamino-3-nitrobenzenesulfonic acid; EXT D&C Yellow 7; e) the triarylmethane dyes of formula (XXIII):

(XXIII), in which formula (XXIII):

- R33, R34, R35 and R36, which are identical or different, represent a hydrogen atom or a group chosen from alkyl, optionally substituted aryl and optionally substituted arylalkyl; particularly an alkyl and benzyl group optionally substituted with a group (O)mS(O-)-, M+ with M+ and m as defined previously;

- R37, R38, R39, R40, R41, R42, R43 and R44, which are identical or different, represent a hydrogen atom or a group chosen from:

- alkyl;

- alkoxy, alkylthio;

- (di) (alkyl) amino;

- hydroxyl, mercapto;

- nitro, nitroso;

- R°-C(X)-X’-, R°-X’-C(X)-, R°-X’-C(X)-X”- with R° representing a hydrogen atom or an alkyl or aryl group; X, X’ and X’ ’ , which are identical or different, representing an oxygen or sulfur atom, or NR with R representing a hydrogen atom or an alkyl group;

- (O) ₂ S(O-)-, M+ with M+ representing a hydrogen atom or a cationic counterion;

- (O)CO— , M+ with M+ as defined previously;

- or alternatively two contiguous groups R41 with R42 or R42 with R43 or R43 with R44 together form a fused benzo group: I'; with I' optionally substituted by one or more groups chosen from i) nitro; ii) nitroso; iii) (O)2S(O-)-, M+; iv) hydroxyl; v) mercapto; vi) (di) (alkyl) amino; vii) R°-C(X)-X'-; viii) R°-X'-C(X)-; ix) R°-X'-C(X)- X"-; with M+, R°, X, X', X" as defined above; in particular, R37 to R40 represent a hydrogen atom and R41 to R44, which are identical or different, represent a hydroxyl or (O)2S(O-)-, M+ group; and, when R43 with R44 together form a benzo group, it is preferentially substituted by an (O)2S(O-)- group; it being understood that at least one of the rings G, H, I or I’ comprises at least one sulfonate radical (O)2S(O-)- or one carboxylate radical -C(O)O-; preferentially sulfonate.

As examples of dyes of formula (XXIII), mention may be made of: Acid Blue 1; Acid Blue 3; Acid Blue 7, Acid Blue 9; Acid Violet 49; Acid Green 3; Acid Green 5 and Acid Green 50. f) the xanthene-based dyes of formula (XXIV): in which formula (XXIV):

- R45, R46, R47 and R48, which are identical or different, represent a hydrogen or halogen atom;

- R49, R50, R51 and R52, which are identical or different, represent a hydrogen or halogen atom, or a group chosen from:

- alkyl;

- alkoxy, alkylthio; - hydroxyl, mercapto;

- nitro, nitroso;

- (O) ₂ S(O-)-, M+ with M+ representing a hydrogen atom or a cationic counterion;

- (O)CO— , M+ with M+ as defined previously; particularly, R49, R50, R51 and R52 represent a hydrogen or halogen atom;

- G represents an oxygen or sulfur atom or a group NRe with Re as defined previously; particularly, G represents an oxygen atom;

- L represents an alkoxide O’, M ⁺ ; a thioalkoxide S’, M ⁺ or a group NRf, with Rf representing a hydrogen atom or an alkyl group, and M ⁺ as defined above; M ⁺ is particularly sodium or potassium;

- L’ represents an oxygen or sulfur atom or an ammonium group: N+RfRg, with Rf and Rg, which are identical or different, representing a hydrogen atom or an optionally substituted alkyl or aryl group; L’ particularly represents an oxygen atom or a phenylamino group optionally substituted with one or more alkyl or (O)mS(O-)-, M+ groups with m and M+ as defined previously;

- Q and Q’, which are identical or different, represent an oxygen or sulfur atom; particularly, Q and Q’ represent an oxygen atom;

- M ⁺ is as defined previously.

As examples of dyes of formula (XXIV), mention may be made of: Acid Yellow 73; Acid Red 51; Acid Red 52; Acid Red 87; Acid Red 92; Acid Red 95; Acid Violet 9; g) the indole -based dyes of formula (XXV):

(XXV), in which formula (XXV):

- R53, R54, R55, R56, R57, R58 , R59 and Reo, which are identical or different, represent a hydrogen atom or a group chosen from:

- alkyl;

- alkoxy, alkylthio;

- hydroxyl, mercapto;

- nitro, nitroso; - R°-C(X)-X’-, R°-X’-C(X)-, R°-X’-C(X)-X”- with R° representing a hydrogen atom or an alkyl or aryl group; X, X’ and X”, which are identical or different, representing an oxygen or sulfur atom, or NR with R representing a hydrogen atom or an alkyl group;

- (O) ₂ S(O-)-, M+ with M+ representing a hydrogen atom or a cationic counterion;

- (O)CO— , M+ with M+ as defined previously;

- G represents an oxygen or sulfur atom or a group NRe with Re as defined previously; particularly, G represents an oxygen atom;

- Ri and Rh, which are identical or different, represent a hydrogen atom or an alkyl group; it being understood that formula (XXV) comprises at least one sulfonate radical (O)2S(O-)-, M+ or one carboxylate radical -C(O)O-, M+; preferentially sodium sulfonate.

As an example of dyes of formula (XXV), mention may be made of: Acid Blue 74; h) the quinoline -based dyes of formula (XXVI): in which formula (XXVI):

- Rei represents a hydrogen or halogen atom or an alkyl group;

- R62, R63 and R64, which are identical or different, represent a hydrogen atom or a group (O)2S(O-)-, M+ with M+ representing a hydrogen atom or a cationic counterion; or alternatively Ro i with R62, or Ro i with R64, together form a benzo group optionally substituted with one or more groups (O)2S(O-)-, M+ with M+ representing a hydrogen atom or a cationic counterion; it being understood that formula (XXVI) comprises at least one sulfonate radical (O)2S(O-)-, M+, preferentially sodium sulfonate.

As examples of dyes of formula (XXVI), mention may be made of: Acid Yellow 2, Acid Yellow 3 and Acid Yellow 5. Among the natural direct dyes that may be used according to the invention, mention may be made of lawsone, juglone, alizarin, purpurin, carminic acid, kermesic acid, purpurogallin, protocatechaldehyde, indigo, isatin, curcumin, spinulosin, apigenidin and orceins. Use may also be made of extracts or decoctions containing these natural dyes and particularly henna-based poultices or extracts.

Preferably, the direct dyes are chosen from anionic direct dyes.

The direct dye(s) can be present in a total amount ranging from 0.001 to 10% by weight, preferably from 0.005 to 5% by weight relative to the total weight of composition C.

Non-carboxylic anionic thickener

Composition C used in the context of the process according to the invention may also comprise at least one non-carboxylic anionic thickener.

For the purposes of the present invention, “non-carboxylic agent” means an agent which does not comprise any carboxylic acid functions (-COOH) or carboxylate functions (-COO ).

For the purposes of the present invention, “thickener” means a compound which increases the viscosity of a composition into which it is introduced at a concentration of 0.05% by weight relative to the total weight of the composition, by at least 20 cps, preferably by at least 50 cps, at room temperature (25 °C), at atmospheric pressure and at a shear rate of 1 s ¹ (the viscosity may be measured using a cone/plate viscometer, a Haake R600 rheometer or the like).

Preferably, the non-carboxylic anionic thickener(s) are chosen from non- carboxylic anionic polymers, more preferentially from anionic polymers bearing a sulfonic group or groups.

For the purposes of the invention, “anionic polymer” means a polymer comprising one or more anionic or anionizable groups, and not comprising any cationic or cationizable groups.

Advantageously, the non-carboxylic anionic thickener(s) are chosen from anionic polymers including at least one ethylenically unsaturated monomer bearing a sulfonic group, in free form or partially or totally neutralized form.

These polymers may be crosslinked or non-crosslinked. They are preferably crosslinked.

These polymers may be associative or non-associative, preferably non- associative.

It is recalled that “associative polymers” are polymers that are capable, in an aqueous medium, of reversibly associating with each other or with other molecules. Their chemical structure more particularly comprises at least one hydrophilic zone and at least one hydrophobic zone.

“Hydrophobic group” means a radical or polymer with a saturated or unsaturated, linear or branched hydrocarbon-based chain, comprising at least 8 carbon atoms, preferably from 10 to 30 carbon atoms, in particular from 12 to 30 carbon atoms and more preferentially from 18 to 30 carbon atoms.

Preferentially, the hydrocarbon-based group originates from a monofunctional compound. By way of example, the hydrophobic group may be derived from a fatty alcohol such as stearyl alcohol, dodecyl alcohol or decyl alcohol. It may also denote a hydrocarbon-based polymer, for instance polybutadiene.

The ethylenically unsaturated monomers bearing a sulfonic group are particularly chosen from vinylsulfonic acid, styrenesulfonic acid, (meth)acrylamido(C i -C22)alkylsulfonic acids, N-(C i -C22)alkyl(meth)acrylamido(C i - C22)alkylsulfonic acids such as undecylacrylamidomethanesulfonic acid, and also partially or totally neutralized forms thereof.

More preferentially, use will be made of (meth)acrylamido(Ci- C22)alkylsulfonic acids, for example acrylamidomethanesulfonic acid, acrylamidoethanesulfonic acid, acrylamidopropanesulfonic acid, 2-acrylamido-2- methylpropanesulfonic acid, methacrylamido-2-methylpropanesulfonic acid, 2- acrylamido-n-butanesulfonic acid, 2-acrylamido-2,4,4-trimethylpentanesulfonic acid, 2-methacrylamidododecylsulfonic acid or 2-acrylamido-2,6-dimethyl-3- heptanesulfonic acid, and also their partially or completely neutralized forms.

2-Acrylamido-2-methylpropanesulfonic acid (AMPS), and also partially or totally neutralized forms thereof, will more particularly be used.

Among the 2-acrylamido-2-methylpropanesulfonic acid copolymers, mention may be made of partially or totally neutralized crosslinked copolymers of 2- acrylamido-2-methylpropanesulfonic acid and of acrylamide; mention may be made in particular of the product described in Example 1 of EP 503 853, and reference may be made to said document as regards these polymers.

Mention may also be made of copolymers of 2-acrylamido-2- methylpropanesulfonic acid or salts thereof and of hydroxyethyl acrylate, such as the compound sold under the name Sepinov EMT 10 by the company SEPPIC (INCI name: hydroxyethylacrylate/sodium acryloyldimethyl taurate copolymer).

The associative AMPS polymers may particularly be chosen from random associative AMPS polymers modified by reaction with a C6-C22 n-monoalkylamine or di-n-alkylamine, and such as those described in patent application WO 00/31154 (forming an integral part of the content of the description). These polymers may also contain other ethylenically unsaturated hydrophilic monomers chosen, for example, from (meth)acrylic acid derivatives, such as esters thereof obtained with monoalcohols or mono- or polyalkylene glycols, (meth)acrylamides, vinylpyrrolidone, or mixtures of these compounds.

The preferred polymers of this family are chosen from associative copolymers of AMPS and of at least one ethylenically unsaturated hydrophobic monomer.

These same copolymers may also contain one or more ethylenically unsaturated monomers not including a fatty chain, such as (meth)acrylic acid derivatives, particularly esters thereof obtained with monoalcohols or mono- or polyalkylene glycols, (meth)acrylamides, vinylpyrrolidone, or mixtures of these compounds.

These copolymers are described particularly in patent application EP- A 750 899, patent US 5 089 578 and in the following publications from Yotaro Morishima:

- Self-assembling amphiphilic polyelectrolytes and their nanostructures, Chinese Journal of Polymer Science, Vol. 18, No. 40, (2000), 323-336;

- Micelle formation of random copolymers of sodium 2-(acrylamido)-2- methylpropanesulfonate and a non-ionic surfactant macromonomer in water as studied by fluorescence and dynamic light scattering, Macromolecules, Vol. 33, No. 10, (2000), 3694-3704;

- Solution properties of micelle networks formed by non-ionic moieties covalently bound to an polyelectrolyte: salt effects on rheological behavior - Langmuir, Vol. 16, No. 12, (2000) 5324-5332;

- Stimuli responsive amphiphilic copolymers of sodium 2-(acrylamido)-2- methylpropanesulfonate and associative macromonomers, Polym. Preprint, Div. Polym. Chem., 40(2), (1999), 220-221.

Among these polymers, mention may be made of:

- crosslinked or non-crosslinked, neutralized or non-neutralized copolymers, including from 15% to 60% by weight of AMPS units and from 40% to 85% by weight of (C8-Ci6)alkyl(meth)acrylamide or (C8-Ci6)alkyl(meth)acrylate units relative to the polymer, such as those described in patent application EP-A750 899;

- terpolymers including from 10 mol% to 90 mol% of acrylamide units, from 0.1 mol% to 10 mol% of AMPS units and from 5 mol% to 80 mol% of n-(Ce- Ci8)alkylacrylamide units, such as those described in patent US-5 089 578.

Mention may also be made of copolymers of totally neutralized AMPS and of dodecyl methacrylate, and also crosslinked and non-crosslinked copolymers of AMPS and of n-dodecylmethacrylamide, such as those described in the Morishima articles mentioned above. Preferably, the non-carboxylic anionic thickener(s) are chosen from sodium 2-acrylamido-2-methylpropanesulfonate/hydroxy ethyl acrylate copolymer, sold by the company SEPPIC (INCI name hydroxyethyl acrylate/sodium acryloyldimethyl taurate copolymer).

Advantageously, the total amount of the non-carboxylic anionic thickener(s) ranges from 0.01 to 20% by weight, preferably from 0.1 to 10% by weight, better still from 0.1 to 5% by weight, and even better still from 0.1 to 3% by weight, relative to the total weight of composition C.

Associative polymers

Composition C according to the invention may further comprise at least one associative polymer other than the compound having at least one carboxylic function as defined previously and other than the non-carboxylic anionic thickener as defined previously.

It is recalled that “associative polymers” are polymers that are capable, in an aqueous medium, of reversibly associating with each other or with other molecules.

Their chemical structure more particularly comprises at least one hydrophilic zone and at least one hydrophobic zone.

“Hydrophobic group” means a radical or polymer with a saturated or unsaturated, linear or branched hydrocarbon-based chain, comprising at least 10 carbon atoms, preferably from 10 to 30 carbon atoms, in particular from 12 to 30 carbon atoms and more preferentially from 18 to 30 carbon atoms.

Preferentially, the hydrocarbon-based group originates from a monofunctional compound. By way of example, the hydrophobic group may be derived from a fatty alcohol such as stearyl alcohol, dodecyl alcohol or decyl alcohol. It may also denote a hydrocarbon-based polymer, for instance polybutadiene.

The associative polymers may be of non-ionic, anionic, cationic or amphoteric nature.

Preferably, the associative polymer(s) are chosen from anionic associative polymers.

Among the associative polymers of anionic type that may be mentioned are:

- (a) those comprising at least one hydrophilic unit and at least one fatty-chain allyl ether unit, more particularly those whose hydrophilic unit is formed by an ethylenic unsaturated anionic monomer, more particularly a vinylcarboxylic acid and most particularly an acrylic acid or a methacrylic acid or mixtures thereof.

Among these anionic associative polymers, those that are particularly preferred according to the invention are polymers formed from 20 to 60% by weight of acrylic acid and/or of methacrylic acid, from 5 to 60% by weight of lower alkyl (meth)acrylates, from 2 to 50% by weight of fatty-chain allyl ether, and from 0 to 1% by weight of a crosslinking agent which is a well-known copolymerizable unsaturated polyethylenic monomer, for instance diallyl phthalate, allyl (meth)acrylate, divinylbenzene, (poly)ethylene glycol dimethacrylate or methylenebisacrylamide.

Among the latter polymers, those most particularly preferred are crosslinked terpolymers of methacrylic acid, of ethyl acrylate and of polyethylene glycol (10 EO) stearyl alcohol ether (Steareth-10), notably those sold by the company Ciba under the names Salcare SC 80® and Salcare SC 90®, which are aqueous 30% emulsions of a crosslinked terpolymer of methacrylic acid, of ethyl acrylate and of steareth-10 allyl ether (40/50/10).

- (b) those comprising i) at least one hydrophilic unit of unsaturated olefinic carboxylic acid type, and ii) at least one hydrophobic unit of the type such as a (C io- C30) alkyl ester of an unsaturated carboxylic acid.

(C 10-C30) alkyl esters of unsaturated carboxylic acids that are useful in the invention comprise, for example, lauryl acrylate, stearyl acrylate, decyl acrylate, isodecyl acrylate and dodecyl acrylate, and the corresponding methacrylates, lauryl methacrylate, stearyl methacrylate, decyl methacrylate, isodecyl methacrylate and dodecyl methacrylate.

Anionic polymers of this type are described and prepared, for example, according to patents US 3 915 921 and US 4 509 949.

Among anionic associative polymers of this type, use will more particularly be made of those constituted of from 95 to 60% by weight of acrylic acid (hydrophilic unit), 4 to 40% by weight of C10-C30 alkyl acrylate (hydrophobic unit) and 0 to 6% by weight of crosslinking polymerizable monomer, or alternatively those constituted of from 98 to 96% by weight of acrylic acid (hydrophilic unit), 1 to 4% by weight of C10- C30 alkyl acrylate (hydrophobic unit) and 0.1 to 0.6% by weight of crosslinking polymerizable monomer such as those described above.

Among said polymers above, those most particularly preferred according to the present invention are the products sold by the company Goodrich under the trade names Pemulen TRI®, Pemulen TR2®, Carbopol 1382®, and even more preferentially Pemulen TRI®, and the product sold by the company SEPPIC under the name Coatex SX®.

Mention may also be made of the acrylic acid/lauryl methacrylate/vinylpyrrolidone terpolymer sold under the name Acrylidone LM by the company ISP. - (c) maleic anhydride/C30-C38 a-olefin/alkyl maleate terpolymers, such as the product (maleic anhydride/C30-C38 a-olefin/isopropyl maleate copolymer) sold under the name Performa V 1608® by the company Newphase Technologies.

- (d) acrylic terpolymers comprising: i) approximately 20 to 70% by weight of an a,P-monoethylenically unsaturated carboxylic acid [A], ii) approximately 20 to 80% by weight of an a,P-monoethylenically unsaturated non- surfactant monomer other than [A], iii) approximately 0.5 to 60% by weight of a non-ionic monourethane which is the reaction product of a monohydric surfactant with a monoethylenically unsaturated monoisocyanate, such as those described in patent application EP-A-0 173 109 and more particularly the terpolymer described in Example 3, namely a methacrylic acid/methyl acrylate/behenyl alcohol dimethyl-meta-isopropenylbenzylisocyanate ethoxylated (40 EO) terpolymer, as an aqueous 25% dispersion.

- (e) copolymers comprising, among their monomers, an a,P- monoethylenically unsaturated carboxylic acid and an ester of an a,P- monoethylenically unsaturated carboxylic acid and of an oxyalkylenated fatty alcohol.

Preferentially, these compounds also comprise, as monomer, an ester of an a,P-monoethylenically unsaturated carboxylic acid and of a C1-C4 alcohol.

An example of a compound of this type that may be mentioned is Aculyn 22® sold by the company Rohm & Haas, which is a methacrylic acid/ethyl aery late/oxy alky lenated stearyl methacrylate terpolymer; and also Aculyn 88, also sold by the company Rohm & Haas.

Advantageously, the associative polymer(s) other than the compounds having at least one carboxylic function described previously and other than the non-carboxylic anionic thickeners described previously are chosen from acrylic associative polymers, more preferentially carboxylic acrylic associative polymers.

Particularly preferably, the associative polymer(s) other than the compounds having at least one carboxylic function described previously and other than the non- carboxylic anionic thickeners described previously are chosen from copolymers including among their monomers an a,P-monoethylenically unsaturated carboxylic acid and an ester of an a,P-monoethylenically unsaturated carboxylic acid and of an oxyalkylenated fatty alcohol.

Advantageously, the total amount of the associative polymer(s) other than the compound(s) having at least one carboxylic function as defined previously and other than the non-carboxylic anionic thickener(s) as defined previously ranges from 0.05 to 15% by weight, preferably from 0.05 to 10% by weight, more preferentially from 0.1 to 5% by weight and even more preferentially from 0.1 to 1% by weight, relative to the total weight of composition C.

Organic solvents

Composition C according to the invention may comprise one or more organic solvents.

Examples of organic solvents that may be mentioned include lower C1-C4 alkanols, such as ethanol and isopropanol; polyols and polyol ethers, for instance 2- butoxy ethanol, 1,2-hexanediol, propylene glycol, pentylene glycol, propylene glycol monomethyl ether and diethylene glycol monoethyl ether and monomethyl ether, and also aromatic alcohols, in particular aromatic monoalcohols, for instance benzyl alcohol, phenoxyethanol, and mixtures thereof.

The organic solvents may be present in a total amount between 0.01 and 60% by weight, preferably between 0.05 and 50% by weight and more preferentially inclusively between 0.1 and 45% by weight relative to the total weight of composition C.

Composition C used in the context of the process according to the invention may be aqueous. The water content may range from 1 to 90% by weight, preferably from 10 to 80% by weight and more preferentially from 20 to 75% by weight relative to the total weight of composition C.

Additives

Composition C used in the context of the process according to the invention may contain any adjuvant or additive usually used.

Among the additives that may be contained in the composition, mention may be made of reducing agents, softeners, antifoams, moisturizers, UV-screening agents, peptizers, fragrances, anionic, cationic, non-ionic or amphoteric surfactants, proteins, vitamins, polymers other than the polymers described previously, preserving agents, silicones, oils, waxes other than the silicones in the form of wax, and mixtures thereof.

Composition C used in the context of the process according to the invention may particularly be in the form of a suspension, a dispersion, a gel, an emulsion, particularly an oil-in-water (O/W) or water-in-oil (W/O) emulsion, or a multiple emulsion (W/O/W or polyol/O/W or O/W/O), in the form of a cream, a mousse, a stick, a dispersion of vesicles, particularly of ionic or non-ionic lipids, or a two-phase or multi-phase lotion. A person skilled in the art may select the appropriate presentation form, and also the method for preparing it, on the basis of their general knowledge, taking into account firstly the nature of the constituents used, particularly their solubility in the support, and secondly the intended application of the composition.

Protocol

Composition C described above may be used on wet or dry hair, and also on any type of fair or dark, natural or coloured, permanent-waved, bleached or relaxed hair.

According to a particular embodiment of the invention, the hair is washed before applying composition C.

Preferably, a washing, rinsing, draining or drying step is performed after composition C is applied to the hair.

More preferentially, a drying step is carried out after the application of composition C to the hair.

The application to the hair can be carried out by any conventional means, in particular using a comb, a fine brush, a coarse brush, a sponge or with the fingers.

The application of composition C to the hair is generally performed at room temperature (between 15 and 25 °C).

After applying composition C to the hair, it is possible to wait for between 1 minute and 6 hours, in particular between 1 minute and 2 hours, more particularly between 1 minute and 1 hour, more preferentially between 1 minute and 30 minutes, before, for example, a washing, rinsing, draining and/or drying step.

After applying composition C, the hair may be left to dry or may be dried, for example at a temperature of greater than or equal to 30°C.

The process according to the invention may thus comprise a step of applying heat to the hair using a heating tool.

The heat application step of the process of the invention can be carried out using a hood, a hairdryer, a straightening iron or a curling iron, a Climazon...

Preferably, the heat application step of the process of the invention is performed using a hairdryer.

When the process of the invention involves a step of applying heat to the hair, the step of applying heat to the hair takes place after applying composition C to the hair.

During the step of applying heat to the hair, a mechanical action may be exerted on the locks, such as combing, brushing or running the fingers through. When the step of applying heat to the hair is performed using a hood or a hairdryer, the temperature is preferably between 30°C and 110°C, preferentially between 50°C and 90°C.

When the step of applying heat to the hair is performed using a straightening iron, the temperature is preferably between 110°C and 220°C, preferably between 140°C and 200°C.

In a particular variant, the process of the invention involves a step (cl) of applying heat using a hood, a hairdryer or a Climazon, preferably a hairdryer, and a step (c2) of applying heat using a straightening or curling iron, preferably a straightening iron.

Step (cl) may be performed before step (c2).

During step (cl), also referred to as the drying step, the hair may be dried, for example at a temperature of greater than or equal to 30°C. According to a particular embodiment, this temperature is greater than 40°C. According to a particular embodiment, this temperature is greater than 45°C and less than 110°C.

Preferably, if the hair is dried, it is dried, in addition to a supply of heat, with a flow of air. This flow of air during drying makes it possible to improve the strand separation of the coating.

During the drying, a mechanical action may be exerted on the locks, such as combing, brushing or running the fingers through.

During step (c2), the passage of the straightening or curling iron, preferably the straightening iron, may be performed at a temperature ranging from 110°C to 220°C, preferably between 140°C and 200°C.

After the heating step, a shaping step may be performed, for example with a straightening iron; the temperature for the shaping step may be between 110°C and 220°C, preferably between 140°C and 200°C.

Preferably, the invention is a process for dyeing the hair comprising the following steps: i) the application to the hair of at least one composition C comprising:

- at least one (poly)carbodiimide compound as described previously;

- at least one compound having at least one carboxylic function as described previously; and

- at least one colouring agent comprising aluminium other than the colouring agents comprising at least one aluminosilicate as described previously; then ii) optionally a leave-on time of said composition C on the hair of from 1 minute to 30 minutes, preferably from 1 to 20 minutes; then iii) optionally a step of washing, rinsing, draining and/or drying said hair. Preferably, composition C also comprises at least one non-carboxylic anionic thickener as described previously.

Preferably, composition C also comprises at least one associative polymer as described above, other than the compound having at least one carboxylic function as defined previously and other than the non-carboxylic anionic thickener as defined previously.

Advantageously, the step of applying composition C to the hair is repeated several times.

According to one preferred embodiment, the dyeing process according to the invention is a process for dyeing the hair consisting in extemporaneously mixing, at the time of use, at least two compositions A and B to obtain a composition C and in applying composition C to the hair, with:

- composition A comprising at least one (poly)carbodiimide compound as described previously;

- composition B comprising at least one compound having at least one carboxylic function as described above, composition A and/or composition B comprising at least one colouring agent comprising aluminium other than the colouring agents comprising at least one aluminosilicate as described previously.

Composition A and/or composition B may optionally comprise at least one non- carboxylic anionic thickener as described previously and/or at least one associative polymer as described above, other than the compound having at least one carboxylic function as defined previously and other than the non-carboxylic anionic thickener as defined previously.

Preferably, composition B comprises at least one colouring agent comprising aluminium other than the colouring agents comprising at least one aluminosilicate as described previously.

Preferably, composition A does not comprise at least one colouring agent comprising aluminium other than the colouring agents comprising at least one aluminosilicate as described previously.

According to this embodiment, compositions A and B are mixed preferably less than 15 minutes before application to the hair, more preferentially less than 10 minutes before application, better still less than 5 minutes before application.

The weight ratio between composition A and composition B preferably ranges from 0.1 to 10, preferentially from 0.2 to 5 and better still from 0.5 to 2, or even from 0.6 to 1.5. In a particular embodiment, the weight ratio between composition A and composition B is equal to 1.

According to one particular embodiment, the hair dyeing process according to the invention is a process for dyeing the hair consisting in extemporaneously mixing, at the time of use, at least two compositions A and B to obtain a composition C and in applying composition C to the hair, with:

- composition A comprising at least one (poly)carbodiimide compound as described previously; and

- composition B comprising at least one compound having at least one carboxylic function as described above, and at least one colouring agent comprising aluminium other than the colouring agents comprising at least one aluminosilicate as described previously; composition A and/or composition B optionally comprising at least one non-carboxylic anionic thickener as described previously and/or at least one associative polymer as described above, other than the compound having at least one carboxylic function as defined previously and other than the non-carboxylic anionic thickener as defined previously.

Advantageously, composition A and/or composition B comprises (comprise) at least one non-carboxylic anionic thickener as described previously, at least one associative polymer as described above, other than the compound having at least one carboxylic function as defined previously and other than the non-carboxylic anionic thickener as defined previously.

The total amount of the (poly)carbodiimide compound(s) preferably ranges from 0.01 to 40% by weight, more preferentially from 0.1 to 30% by weight, better still from 0.5 to 20% by weight and even more preferentially from 1 to 12% by weight relative to the total weight of composition A.

The total amount of the compound(s) having at least one carboxylic function preferably ranges from 0.2 to 60% by weight, more preferentially from 1 to 40% by weight, better still from 1 to 30% by weight, and even more preferentially from 2 to 20% by weight relative to the total weight of composition B.

The total amount of the aqueous dispersion(s) of particles of polymer(s) chosen from polyurethanes, acrylic polymers, and mixtures thereof, preferably ranges from 0.2 to 60% by weight, more preferentially from 1 to 50% by weight, better still from 1 to 40% by weight, and even more preferentially from 2 to 30% by weight, relative to the total weight of composition B.

According to a particular embodiment, the total amount of the aqueous dispersion(s) of particles of acrylic polymer(s) preferably ranges from 0.2 to 60% by weight, more preferentially from 1 to 50% by weight, better still from 1 to 40% by weight, and even more preferentially from 2 to 30% by weight, relative to the total weight of composition B.

Multi-compartment device (kit)

The present invention also relates to a device for dyeing the hair comprising a plurality of compartments containing:

- in a first compartment, a composition A comprising: a) at least one (poly)carbodiimide compound as described previously;

- in a second compartment, a composition B comprising: b) at least one compound comprising at least one carboxylic function as described previously, composition A and/or composition B comprising: c) at least one colouring agent comprising aluminium other than the colouring agents comprising at least one aluminosilicate.

The present invention will now be described more specifically by means of examples, which do not in any way limit the scope of the invention. However, the examples make it possible to support specific features, variants and preferred embodiments of the invention.

EXAMPLES

The (poly)carbodiimide(s) of the invention are accessible via synthetic methods known to those skilled in the art starting from commercial products or reagents that can be synthesized according to chemical reactions that are also known to those skilled in the art. Mention may be made, for example, of the book Sciences of Synthesis - Houben - Weyl Methods of Molecular Transformations, 2005, Georg Thiem Verlag Kg, Rudigerstrasse 14, D-70469 Stuttgart, or the American patent US 4 284 730 or the Canadian patent application CA 2 509 861.

More particularly, the process for preparing the (poly)carbodiimides of the invention involves, in a first step, a diisocyanate reagent (1):

O=C=N-Li-N=C=O (1), in which formula (1) Li is as defined previously, which reacts in the presence of a carboimidation catalyst (2) such as those described in US 4 284 730, particularly phosphorus-based catalysts particularly chosen from phospholene oxides and phospholene sulfoxides, diaza- and oxaza-phospholanes, preferably under an inert atmosphere (nitrogen or argon), and in particular in a polar solvent which is preferably aprotic such as THF, glyme, diglyme, 1,4-dioxane or DMF, at a temperature between room temperature and the reflux temperature of the solvent, preferably approximately 140°C; to give the carbodiimide diisocyanate compound (3):

O=C=N-Li-(N=C=N-Li) _n -N=C=O (3), in which formula (3) Li and n are as defined previously. Benzoyl halogen such as benzoyl chloride may be added to deactivate the catalyst.

To obtain “symmetrical” (poly)carbodiimides, during the second step of the preparation process, compound (3) reacts with 1 molar equivalent (1 eq.) of nucleophilic reagent Ri-Xi-H then 0.5 eq. of reagent H-E-H with Ri, Xi and E as defined previously, to give the “symmetrical” compound (4) according to the invention:

[Ri-Xi-C(O)-NH-Li-(N=C=N-Li) _n -NH-C(O)] ₂ -E (4), in which formula (4) Ri , Xi , Li , n and E are as defined previously. According to one variant to obtain compound (4) from (3), it is possible first to add 0.5 eq. of reagent H-E-H and then 1 eq. of reagent Ri-Xi-H.

To obtain “dissymmetrical” (poly)carbodiimides, during the second step of the preparation process, compound (3) reacts with 1 molar equivalent (1 eq.) of nucleophilic reagent Ri-Xi-H, then 1 eq. of reagent H-E-H with Ri, Xi and E as defined above, to give compound (5):

Ri -Xi-C(O)-NH-Li -(N=C=N-Li ) _n -NH-C(O)-E-H (5), in which formula (5) Ri, Xi, Li, n and E are as defined previously.

According to one variant to obtain compound (5) from (3), it is possible first to add 1 eq. of reagent Ri-Xi-H, then 0.5 eq. of reagent H-E-H.

During a third step, compound (5) reacts with 1 eq. of compound (6)

R ₂ -X ₂ -C(O)-NH-LI-(N=C=N-LI)Z-N=C=O (6); said compound (6) is prepared beforehand from compound (3’):

O=C=N-Li-(N=C=N-Li) _z -N=C=O (3’), in which formula (3’) Li and z are as defined previously, which reacts with 1 eq. of nucleophilic reagent R ₂ -X ₂ -H with Li, R ₂ , X ₂ and z as defined previously, to give the dissymmetrical compound (7):

R i -X i -C(O)-NH-L i -(N=C=N-L i ) _n -NH-C(O)-E-C(O)-NH-L i -(N=C=N- LI)Z-NH-C(O)-X ₂ -R ₂ (7), in which formula (7) Ri, Xi, Li, R ₂ , X ₂ , n, z and E are as defined previously.

It is also possible to react 1 molar equivalent of compound O=C=N-Li- (N=C=N-Li) _z -N=C=O (3’) with 1/w molar equivalent of H-E-H, then 1 eq. of nucleophilic reagent R ₂ -X ₂ -H to give compound (8):

H-[E-C(O)-NH-LI-(N=C=N-LI) _Z ]W-NH-C(O)-X ₂ -R ₂ (8), in which formula (8) Li, R2, X2, z and E are as defined previously, and w is an integer between 1 and 3; more preferentially, w = 1.

This last compound (8) can then react with 1 eq. of compound (4’):

Ri-Xi-C(O)-NH-Li-(N=C=N-Li) _n -N=C=O (4’), (said compound (4’) being able to be synthesized by reaction of 0.5 eq. of nucleophilic reagent R1-X1-H with 1 equivalent of compound (3)), to give the (poly)carbodiimide (9) of the invention:

R 1 -X 1 -C(O)-NH-L 1 -(N=C=N-L 1 ) _n -NH-C(O)-[E-C(O)-NH-L 1 -(N=C=N- LI) _Z ] _W -NH C(O)-X ₂ -R2 (9), in which formula (9) Li, Ri, Xi, R2, X2, n, z, w and E are as defined previously.

The (poly)carbodiimide compounds, and similarly all the reaction intermediates and reagents, may be purified via conventional methods known to those skilled in the art, such as extraction with water and water-immiscible organic solvent, precipitation, centrifugation, filtration and/or chromatography.

Example 1: Process for synthesizing the (poly)carbodiimide compound

50 g of 4,4’-dicyclohexylmethane diisocyanate and 0.5 g of 4,5-dihydro-3- methyl-l-phenyl-lH-phosphole 1-oxide were placed with stirring in a 500 ml threenecked round-bottomed flask equipped with a thermometer, a stirrer and a reflux tube.

The reaction medium was heated at 140°C under nitrogen for 4 hours, the reaction being monitored by infrared spectroscopy by means of the absorption of the isocyanate functions between 2200 and 2300 cm ¹ , and then cooled to 120°C.

A mixture of 5.3 g of polyethylene glycol monomethyl ether and 1.2 g of 1,4- butanediol are introduced with stirring into the reaction medium. The temperature of 120°C is maintained until the isocyanate functions have totally disappeared, monitored by infrared spectroscopy at 2200-2300 cm ¹ , and is then cooled to room temperature.

After cooling to room temperature, the reaction medium is poured dropwise with vigorous stirring into a 500 ml glass beaker containing 85 g of distilled water, to give the desired product in the form of a translucent yellow liquid.

Example 2

Compositions A, B 1 and B2 as described in table 1 below were prepared: the amounts are expressed as g of starting material as obtained/100 g, unless otherwise mentioned.

[Table 1]

(1) synthesized according to the synthetic process described in Example 1 (containing 40% active material in water),

(2) sold by the company SEPPIC under the name Sepinov EMTIO (containing 90% active material).

[Table 2]

(3) sold by the company Daito Kasei Kogyo under the trade name Daitosol 3000SLPN-

PE1 (aqueous dispersion containing 30% active material)

(4) sold by the company Rohm & Haas under the trade name Aculyn 22®

(oxyalkylenated methacrylic acid/ethyl acrylate/stearyl methacrylate terpolymer containing 30% active material) (5) sold by the company ECKART under the trade name SYNCRYSTAL SOFT SILVER,

(6) sold by the company Siberline under the trade name Starbrite Reveal AQ 4172PA.

Two mixtures were then produced. Composition A was mixed with each of compositions B l and B2 in a 50/50 weight ratio to obtain two compositions Cl and C2.

Thus, the process using composition Cl is a comparative process. The process using composition C2 is a process according to the invention.

Protocol

Each of compositions Cl and C2 is applied to locks of TD 4 (tone depth 4) natural hair, or to locks of dry natural hair containing 90% white hairs (NW90), in a proportion of 0.8 g of composition per gram of lock. The locks of hair are then dried with a hairdryer at medium heat, while being combed.

The locks of hair are then stored at room temperature and humidity for 24 hours.

The measurements of lightening and of coverage were then carried out. These measurements were performed using a Minolta Spectrophotometer CM3600A colorimeter (illuminant D65, angle 10°, specular component included). The colour is defined according to the CIE L*a*b* system, in which L* represents the intensity of the colour, a* indicates the green/red colour axis and b* the blue/yellow colour axis.

Evaluation of the lightening

The lightening is demonstrated with the aid of the component L*. The higher the value of L*, the lighter the colour appears.

For these measurements, locks of TD 4 (tone depth 4) natural hair were used.

The results are collated in Table 3 below.

[Table 3]

It is clearly apparent that the locks of hair treated with the process according to the invention have a value of L* approximately two times higher than that of the locks of hair treated with a comparative process. Thus, the process according to the invention makes it possible to obtain a significatively lighter colour. In other words, the coloured coating obtained with the process according to the invention exhibits an improved level of lightening.

Evaluation of the coverage

The coverage of a composition is represented by the colour difference AE obtained between the locks of TD (tone depth) 4 natural hair (dark hair) and the locks of natural hair containing 90% white hairs (very light hair), after dyeing. The lower the colour difference AE, the better the coverage.

Thus, to determine the coverage, the compositions used are applied to a lock of TD 4 natural hair and to a lock of natural hair containing 90% white hairs. The greater the coverage of the composition, the closer the colour results on a lock of TD 4 natural hair and on a lock of natural hair containing 90% white hairs.

The results are collated in Table 4 below.

[Table 4]

It is clearly apparent that a greater colour difference is obtained between the locks of NW90 and TD4 hair when they are treated with the comparative process than when they are treated with the process according to the invention.

Furthermore, the ratio between the colour differences AE (41.1/4.6) is approximately equal to 9. Thus, the process according to the invention makes it possible to obtain a coverage 9 times greater than that with the comparative process.

Consequently, the coloured coating obtained with the process according to the invention has a significantly improved coverage.