WO2019202140A1

WO2019202140A1 - Process for dyeing keratin fibres comprising the application of a chromenol/chromen-2-one derivative, composition and device

Info

Publication number: WO2019202140A1
Application number: PCT/EP2019/060219
Authority: WO
Inventors: Cécile MAILLARD-BENNASAR; Hervé David
Original assignee: L'oreal
Priority date: 2018-04-19
Filing date: 2019-04-19
Publication date: 2019-10-24
Also published as: FR3080284A1; FR3080284B1

Abstract

The subject of the present application is a process for dyeing keratin fibres, in particular human keratin fibres such as the hair, comprising at least one step of applying to said keratin fibres one or more particular oxidation couplers of chromenol/chromen-2-one type, the dyeing compositions comprising such derivatives and also the devices using these compounds.

Description

Process for dyeing keratin fibres comprising the application of a chromenol/chromen-2-one derivative, composition and device

It is known practice to dye keratin fibres, and especially the human hair, with dyeing compositions containing oxidation dye precursors, generally called oxidation bases, such as ortho- or para-phenylenediamines, ortho- or para- aminophenols and heterocyclic compounds. These oxidation bases are colourless or weakly coloured compounds which, when combined with oxidizing products, are able to produce coloured compounds by a process of oxidative condensation.

It is also known that the shades obtained with these oxidation bases may be varied by combining them with couplers or colour modifiers, the latter being chosen especially from aromatic meta-diaminobenzenes, meta-aminophenols, meta diphenols and certain heterocyclic compounds such as indole compounds.

The variety of molecules used as oxidation bases and couplers allows a wide range of colours to be obtained.

The "permanent" colouration obtained by means of these oxidation dyes should moreover satisfy a certain number of requirements. Thus, it should allow shades to be obtained in the desired intensity, and it should show good resistance to external agents such as light, bad weather, washing, permanent waving treatments, perspiration and rubbing.

The dyes must also allow grey hair to be covered, and they must be as unselective as possible, i.e. they must make it possible to produce the smallest possible colouration differences all along the same lock of keratin fibre, which is generally differently sensitized (i.e. damaged) between its end and its root.

Heterocyclic oxidation bases make it possible to obtain a wide range of colours, but the combining thereof with conventional couplers sometimes lacks homogeneity and chromaticity and the selectivities are often considerable.

Moreover, it appears that market and consumer demand for hair dyeing products is turning to naturalness. In the field of natural dyeing, dyeing products as a general rule involve those which formulate only natural direct dyes or extracts containing them. While there are many consumer benefits (effectively healthy look, colouration perceived to be natural, etc.), these products still have some imperfections, such as build-up judged to be inferior compared with the synthetic versions, resistance to repeated shampooing judged to be still too weak, off-putting colour change.

There is therefore a real need to provide oxidation dyeing products, in particular couplers, derived from oxidation precursors which are of natural origin or are naturally occurring, or are constructed from natural building blocks which make it possible to equal or even improve the performance level of the oxidation dyeing. It would be desirable for the oxidation dye(s), in particular the oxidation couplers, to make it possible to dye keratin fibres in an intense, resistant and chromatic manner which is relatively unselective along the fibre, with good build-up of the colour, and capable of giving colourations that are resistant to the various attacks to which the fibres may be subjected, such as inclement weather, washing and perspiration.

These objectives are achieved with the present invention, a subject of which is in particular a process for dyeing keratin fibres, in particular human keratin fibres such as the hair, comprising at least i) a step of applying to said keratin fibres one or more oxidation couplers chosen from the compounds of formula (IA) below; and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and mixtures thereof:

in which formula (IA):

- z and q, which may be identical or different, equal 0 or 1, it being understood that z and q cannot simultaneously denote 0;

t represents an integer equal to 0, 1 or 2, it being understood that, when t is 2, then the R_SA radicals may be identical or different; R_IA and R_2A, which may be identical or different, represent:

• a hydroxyl radical,

• a linear or branched Ci-C₄ alkoxy radical, optionally substituted with one or more hydroxyl groups,

• an amino radical -NH₂, or

• an -N(R_4A)(R'_4A) radical in which R_4A and R'_{4 \}, which may be identical or different, represent:

o a hydrogen atom,

o a (Ci-C₆)alkyl or (C₂-C₆)alkenyl group, optionally substituted with one or more groups, which may be identical or different, chosen from i) hydroxyl, ii) amino -NH₂, iii) carboxy -COOH, iv) (Ci-C₄)alkoxycarbonyl, v) hydroxysulfonyl -S0₃H, vi) dihydroxyphosphonyl -P(0)(0H)₂,

o or R_4A and R'_4A can form, with the nitrogen atom to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, 5- to 7-membered heterocycle:

^■ optionally comprising one or more heteroatoms and/or additional groups chosen from -0-, -S-, -NH-, -N(R"_4A)- where R"_4A represents a (Ci-C₄)alkyl, -S(O)-, -S(0)₂-, -C(O)- or -C(S)- group and/or

^■ optionally substituted with one or more radicals, which may be identical or different, chosen from i) hydroxyl, ii) Ci-C₄ (hydroxy)alkyl, iii) Ci-C₄ alkoxycarbonyl and iv) carboxy -COOH radicals;

R_3A represents a hydrogen atom, a halogen atom, a carboxy -COOH radical, or a Ci-C₄ alkoxy radical optionally substituted with one or more hydroxyl groups;

R5_A represents i) a linear or branched Ci-C₆ alkyl radical optionally substituted with one or more groups, which may be identical or different, chosen from:

• hydroxyl,

• amino -NH₂,

• carboxy COOH

• (Ci-C₄)alkoxycarbonyl, or ii) a phenyl radical optionally substituted with one or more halogen atoms such as chlorine and/or bromine, and/or with one or more hydroxyl groups; R_6A represents:

• a hydrogen atom,

· a linear or branched Ci-C₆ alkyl radical, optionally substituted with one or more groups, which may be identical or different, chosen from i) hydroxyl, ii) aromatic or non-aromatic, saturated or unsaturated, preferably saturated, heterocycle-C(O)- wherein heterocycle comprises 5 or 6 ring members, comprising from 1 to 3 heteroatoms chosen from O, S and N and optionally substituted with one or more (Ci-C₄)alkyl groups, and/or

optionally interrupted with one or more heteroatoms and/or groups chosen from O, S, NH, N(R'"₄), C(O), and combinations thereof such as -O-C(O)-, -C(0)-0-, -NH-C(O)-, -C(0)-NH-, -C(0)-N(R"'_4A)-, - C(0)-0R"'_4A, with R"'_4A representing a (Ci-C₄)alkyl group optionally substituted with a hydroxyl;

more preferentially R_6A represents a hydrogen atom, -C(0)-N(R"'_4AK or -C(0)-0R"'_4A, with R"'_4A representing an ethyl or hydroxyethyl group; R_2A and R_6A, or R_2A and R_3A can form, with the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated heterocycle comprising from 5 to 7 ring members:

• optionally comprising one or more heteroatoms and/or additional groups chosen from -O-, -S-, -NH-, -N(R"_4A)- with R"_4A as defined above, - S(O)-, -S(0)₂-, -C(O)-, -C(S)- or a combination thereof such as -OC(O)-, C(0)0- and/or

• optionally substituted with one or more radicals, which may be identical or different, chosen from i) hydroxyl, ii) Ci-C₄ (hydroxy)alkyl, iii) Ci-C₄ alkoxycarbonyl and iv) carboxy -COOH radicals;

X denotes a -(CH₂)- or -CH(R_SB)- or -CO- diradical with R_SB having the same definition as Rs_A mentioned above;

Y denotes a -(CH₂)- or -CH(Rsc)- or -CO- diradical with Rsc having the same definition as Rs_A mentioned above when Y is bonded by two single bonds, or Y denotes a =(CH)- or =C(Rsc)- triradical with Rs_C as defined above when Y is bonded by 1 single bond and 1 double bond; it being understood that X and Y cannot simultaneously denote -CO-;

R5_A and R_SB, or R_SB and Rsc can form, with the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated heterocycle comprising from 5 to 7 ring members:

· optionally comprising one or more heteroatoms and/or additional groups chosen from -0-, -S-, -NH-, -N(R"_4A)- with R"_4A as defined above, - S(O)-, -S(0)₂-, -C(O)-, -C(S)- and/or

denotes a single bond or a double bond.

The applicant has in particular noted, surprisingly, that the process according to the invention makes it possible to obtain colourations of the keratin fibres which are powerful, resistant, chromatic and relatively unselective along the fibre, and/or with good build-up of the colour.

The compounds of formula (IA) according to the invention produce a wide colour range in oxidation dyeing. These couplers make it possible in particular to broaden the colour range. In addition, these chromenol/chromen-2-one derivatives of formula (IA) make it possible to obtain colourations with varied shades, in particular light shades, with glints, natural shades, dark natural shades.

The compounds of formula (IA) according to the invention can thus give colourations that are resistant to the various attacking factors to which keratin fibres may be subjected, such as inclement weather, light, washing and perspiration.

More particularly, the applicant has noted that the process according to the invention makes it possible to obtain colourations of the keratin fibres which are persistent with respect to shampooing operations, more particularly persistent with respect to at least two shampooing operations. A subject of the invention is also a cosmetic composition comprising one or more oxidation couplers of formula (IA) as defined above, and one or more oxidation bases. A subject of the invention is also a process for dyeing keratin fibres, in particular human keratin fibres such as the hair, comprising at least i) a step of applying to said keratin fibres one or more oxidation couplers chosen from the compounds of formula (IA) as defined above; and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and mixtures thereof.

A subject of the invention is also a multicompartment kit or device comprising a first compartment containing one or more oxidation couplers of formula (IA) as defined above, and a second compartment comprising one or more chemical oxidizing agents as defined below.

Other features, aspects, objects and advantages of the present invention will emerge even more clearly on reading the description and the examples that follow.

In the subsequent text, and unless otherwise indicated:

- the limits of a range of values are included in that range, in particular in the expressions "between... and ..." and "ranging from ... to ...";

- the expressions“at least one” and“at least” used in the present description are equivalent to the expressions“one or more” and“greater than or equal to”, respectively;

- the term“keratin fibres” according to the present application mainly denotes human keratin fibres and in particular the hair;

the term“alkyl” is intended to mean a linear or branched hydrocarbon-based radical, preferably of Ci-C₆;

the term“ unsaturated alkyl” is intended to mean a linear or branched, preferably Ci-C₆, hydrocarbon-based radical comprising at least one carbon-carbon double bond or at least one carbon-carbon triple bond, preferably at least one carbon- carbon double bond;

the term“hydroxyalkyl” is intended to mean an alkyl group as defined above substituted with one or more hydroxyl groups, preferably a (Ci-C₆)alkyl group substituted with a hydroxyl group, such as hydroxyethyl;

the term“ (hydroxy )alkyl” is intended to mean an alkyl or hydroxyalkyl group as defined above; the term "alkoxy" is intended to mean a group -O-alkyl with alkyl as defined above; in particular, alkoxy denotes a methoxy or ethoxy group;

the term“ hydroxyalkoxy” is intended to mean an alkoxy group as defined above, substituted with one or more hydroxyl groups, preferably a (Ci-C₆)alkoxy group substituted with a hydroxyl group, such as b-hydroxyethoxy;

the term“(hydroxy )alkoxy” is intended to mean an alkoxy or hydroxyalkoxy group as defined above;

the term“ hetewcycle” or“ heterocyclic” radical is intended to mean a non- cationic cyclic radical preferably comprising from 5 to 14 ring members and from 1 to 5 heteroatoms such as O, S and N, and/or at least one of the ring members of which denotes a -C(O)- diradical; more preferentially, said heterocyclic radical is monocyclic or bicyclic, comprising from 5 to 10 ring members and/or one of the ring members of which denotes a -C(O)- diradical; and from 1 to 3 heteroatoms chosen from N, O and S, particularly N and O, such as imidazolyls, pyridinyls, piperazinyls, pyrrolidinyls, morpholinyls, pyrimidinyls, thiazolyls, benzimidazolyls, benzothiazolyls, oxazolyls, benzotriazolyls, pyrazolyls, triazolyls, benzoxazolyls, piperidinyls, tetrahydropyrans, tetrahydropyranones; more particularly, said heterocyclic radical is monocyclic comprising from 5 to 6 ring members, one of which optionally denotes -C(O)-, and from 1 to 2 heteroatoms chosen from N and O, such as pyrazinyls, tetrahydropyrans or tetrahydropyranones ;

the term“(7 ietero)cycle” or“( heterocyclic” radical is intended to mean a hydrocarbon-based cyclic radical preferably comprising from 5 to 14 ring members, or a“ hetewcycle” radical as defined above;

Advantageously, R_SA represents i) a linear or branched C i -C₆ alkyl radical optionally substituted with one or more groups, which may be identical or different, chosen from:

• hydroxyl,

• amino -NH₂,

• carboxy COOH

• (Ci-C₄)alkoxycarbonyl, or ii) a phenyl radical optionally substituted with one or more halogen atoms such as chlorine and/or bromine, and/or with one hydroxyl groups.

According to one particular embodiment of the invention, the compounds of formula (IA) are such that t = 0 or 1 and Rs_A represents a linear or branched Ci-C₆, preferably linear Ci-C₄, alkyl radical, said alkyl radical being optionally substituted with a group chosen from i) hydroxyl, ii) carboxy COOH, iii) (Ci- C₄)alkoxycarbonyl, and in particular optionally substituted with ii) carboxy COOH, iii) (Ci-C₄)alkoxycarbonyl.

According to another particular embodiment of the invention, the compounds of formula (IA) are such that R_IA and R_2A, which may be identical or different, represent:

• a hydroxyl radical;

· a linear or branched Ci-C₄ alkoxy radical, optionally substituted with one or more hydroxyl groups, in particular optionally substituted with a hydroxyl group;

• an -NH(R_4A) radical in which R_4A represents a (Ci-C₆)alkyl, in particular (Ci-C₄)alkyl, group, said alkyl radical being optionally substituted with one or more groups, which may be identical or different, chosen from i) hydroxyl, iii) carboxy

-COOH, iv) (Ci-C₄)alkoxycarbonyl such as C0₂Me.

According to another particular embodiment of the invention, the compounds of formula (IA) are such that R_3A represents a hydrogen atom.

According to another particular embodiment of the invention, the compounds of formula (IA) are such that R_6A represents:

• a hydrogen atom;

• a linear or branched, in particular linear, Ci-C₆ alkyl radical, said alkyl radical being optionally substituted with a group chosen from i) hydroxyl, ii) heteroc-C(O)- with heteroc comprising 5 or 6 ring members, and being saturated, and comprising 1 or 2 heteroatoms chosen from O and N, and optionally substituted with one or more groups (Ci-C₄)alkyl such as methyl, iii) (Ci-C₄)alkoxycarbonyl such as C0₂Me, C0₂Et, iv) amido -CO-NH-R_a with R_a denoting a C₁-C₄ (hydroxy)alkyl radical such as hydroxyethyl.

According to another particular embodiment of the invention, the compounds of formula (IA) are such that R_2A and R _A, or R_2A and R_3A form, with the carbon atoms to which they are attached, a saturated heterocycle comprising from 5 to 7 ring members, in particular 6 ring members, said heterocycle comprising a group chosen from -O - or -OC(O)- or -C(0)0-.

According to a particular form of the invention, the compounds of formula

(IA) are such that ^' denotes a single bond, q =1, Y denotes a -(CH₂)- diradical, z = 0 or 1 and X denotes a -(CH₂)- or -CO- diradical. According to another particular form of the invention, the compounds of

>>

formula (IA) are such that denotes a double bond, q =1, Y denotes a =(CH)- triradical, z = 1 and X denotes a -CO- diradical.

Preferably, the compounds of formula (IA) are chosen from the compounds of formula (I), (II) or (III) below; and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and the mixtures thereof:

in which formulae (I), (II) and (III), independently from one formula to the other: n and m, which may be identical or different, are equal to 0 or 1 ;

p represents an integer equal to 0, 1, 2 or 3, it being understood that, when p is 2 or 3, then the R5 radicals may be identical or different;

p' and p", which may be identical or different, are equal to 0, 1 or 2, it being understood that, when p’ is 2, then the R'5 radicals may be identical or different, or that, when p” is 2, then the R"s radicals may be identical or different;

Ri, R'i, R"i, R₂, R'₂ and R"₂, which may be identical or different, represent:

• a hydroxyl radical,

• a linear or branched C₁-C₄ alkoxy radical, optionally substituted with one or more hydroxyl groups,

• an amino radical -NH₂, or

• an -N(R₄)(R'₄) radical in which R₄ and R'₄, which may be identical or different, represent:

o a hydrogen atom,

o a (Ci-C₆)alkyl or (C₂-C6)alkenyl group, optionally substituted with one or more groups, which may be identical or different, chosen from i) hydroxyl, ii) amino -NH₂, iii) carboxy -COOH, iv) (Ci-C₄)alkoxycarbonyl, v) hydroxysulfonyl -SO3H, vi) dihydroxyphosphonyl -P(0)(OH)₂,

o or R₄ and R'₄ can form, with the nitrogen atom to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, 5- to 7-membered heterocycle:

^■ optionally comprising one or more heteroatoms and/or additional groups chosen from -O-, -S-, -NH-, -N(R"₄)- where R"₄ represents a (Ci-C₄)alkyl, -S(O)-, -S(0)₂-, -C(O)- or -C(S)- group and/or

R3, R'3 and R^M3, which may be identical or different, represent a hydrogen atom, a halogen atom, a carboxy -COOH radical, or a Ci-C₄ alkoxy radical optionally substituted with one or more hydroxyl groups; R₅ represents i) a linear or branched Ci-C₆ alkyl radical optionally substituted with one or more groups, which may be identical or different, chosen from:

• hydroxyl,

· amino -NH₂, or

ii) a phenyl radical optionally substituted with one or more halogen atoms such as chlorine and/or bromine, and/or with one or more hydroxyl groups; R'₅ and R^M ₅, which may be identical or different, represent i) a linear or branched Ci-C₆ alkyl radical optionally substituted with one or more groups, which may be identical or different, chosen from:

• hydroxyl,

• carboxy -COOH,

• halogen atom(s) such as bromine and/or chlorine,

• C₁-C₄ alkoxycarbonyl, or

ii) a phenyl radical optionally substituted with one or more halogen atoms such as chlorine and/or bromine, and/or with one or more hydroxyl groups; R₆ represents:

• a hydrogen atom;

• a linear or branched Ci-C₆ alkyl radical, optionally substituted with one or more groups, which may be identical or different, chosen from i) hydroxyl, ii) aromatic or non-aromatic, saturated or unsaturated, preferably saturated, heterocycle-C(O)- wherein heterocycle comprises 5 or 6 ring members, comprising from 1 to 3 heteroatoms chosen from O, S and N and optionally substituted with one or more (Ci-C₄)alkyl groups, and/or

optionally interrupted with one or more heteroatoms and/or groups chosen from O, S, NH, N(R'"₄), C(O), and combinations thereof such as -O-C(O)-, -C(0)-0-, -NH-C(O)-, -C(0)-NH-, -C(0)-N(R'"₄)-, -C(O)- OR'"₄, with R'"₄ representing a (Ci-C₄)alkyl group optionally substituted with a hydroxyl;

more preferentially R₆ represents a hydrogen atom, -C(0)-N(R'"₄)-, or -C(0)-OR'"₄, with R'"₄ representing an ethyl or hydroxyethyl group;

R'₆ and R^M ₆, which may be identical or different, are as defined for R₆, preferably R'₆ and R'V, represent a hydrogen atom; R₂ and R₆ or R₂ and R₃, and/or R'₂ and RV, or R'₂ and R'₃, and/or R"₂ and R" can form, with the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, heterocycle comprising from 5 to 7 ring members:

· optionally comprising one or more heteroatoms and/or additional groups chosen from -0-, -S-, -NH-, -N(R"₄)- with R"₄ as defined above, -S(O)-,

-S(0)₂-, -C(O)-, -C(S)- and/or

when p' and/or p" is (are) equal to 2, the two R's radicals and/or the two R"s radicals can form, with the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, (hetero)cycle comprising 5 or 6 ring members:

· optionally comprising one or more heteroatoms and/or additional groups chosen from -0-, -S-, -NH-, -N(R"₄)- with R"4 as defined above, -S(O)-, -S(0)₂-, -C(O)-, -C(S)- and/or

• optionally substituted with one or more radicals, which may be identical or different, chosen from i) hydroxyl, ii) Ci-C₄ (hydroxy)alkyl, iii) Ci-C₄ alkoxycarbonyl and iv) carboxy -COOH radicals.

Advantageously, R5 represents i) a linear or branched Ci-C₆ alkyl radical optionally substituted with one or more groups, which may be identical or different, chosen from:

· hydroxyl,

• amino -NH₂, or

ii) a phenyl radical optionally substituted with one or more halogen atoms such as chlorine and/or bromine, and/or with one hydroxyl groups.

Advantageously, R'5 and R"s, which may be identical or different, represent i) a linear or branched Ci-C₆ alkyl radical optionally substituted with one or more groups, which may be identical or different, chosen from:

• hydroxyl,

• hydroxycarbonyl -COOH,

• halogen atom(s) such as bromine and/or chlorine, • C1-C4 alkoxycarbonyl, or

Dyeing process

The present invention relates to a process for dyeing keratin fibres, in particular human keratin fibres such as the hair, comprising at least i) a step of applying to said keratin fibres one or more oxidation couplers chosen from the compounds of formula (IA) or the compounds of formula (I), (II) or (III) as defined above; and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and mixtures thereof.

The compounds of formulae (IA), (I), (II) and (III) can be in the form of an organic or mineral acid or base salt.

The term “organic or mineral acid salt” is intended to mean more particularly those chosen from the addition salts with a cosmetically acceptable acid, such as the acidifying agents defined below, for instance the salts derived from i) hydrochloric acid HC1, ii) hydrobromic acid HBr, iii) sulfuric acid H₂S0₄, iv) alkylsulfonic acids: Alk-S(0)₂OH such as methylsulfonic acid and ethylsulfonic acid; v) arylsulfonic acids: Ar-S(0)₂OH such as benzenesulfonic acid and toluenesulfonic acid; vi) citric acid; vii) succinic acid; viii) tartaric acid; ix) lactic acid; x) alkoxysulfinic acids: Alk-0-S(0)0H such as methoxysulfinic acid and ethoxysulfinic acid; xi) aryloxysulfinic acids such as tolueneoxysulfinic acid and phenoxysulfinic acid; xii) phosphoric acid H P0₄; xiii) acetic acid CH₃C(0)-OH; xiv) triflic acid CF S0₃H; xv) tetrafluoroboric acid HBF₄, and xvi) hydroiodic acid HI.

More particularly, the compounds of formulae (IA), (I), (II) and (III) are optionally salified with strong mineral acids, such as HC1, HBr, HI, H₂S0₄ or H P0₄, or organic acids, for instance acetic acid, lactic acid, tartaric acid, citric acid, succinic acid, benzenesulfonic acid, para-toluenesulfonic acid, formic acid or methanesulfonic acid. The term “organic or mineral base salt” is intended to mean more particularly those chosen from the addition salts with a cosmetically acceptable base such as basifying agents as defined below, for instance alkali metal hydroxides, such as sodium hydroxide or potassium hydroxide, aqueous ammonia, amines or alkanolamines, or with a cosmetically acceptable anionic counterion as defined above.

The compounds of formulae (IA), (I), (II) and (III) may also be in the form of solvates, for example a hydrate or a solvate of a linear or branched alcohol such as ethanol or isopropanol.

According to one particular embodiment of the invention, n is 0.

According to another particular embodiment of the invention, n is 1.

According to one variant, p is 0.

According to one particular embodiment of the invention, m is 0.

According to another particular embodiment of the invention, m is 1.

Preferably, Ri, R’i and/or R”i represent, independently of one another, a hydroxyl radical.

According to one variant of the invention, Ri represents an

-N(R₄)(R'₄) group in which R₄ and R'₄, independently of one another, represent:

o a hydrogen atom,

o a (Ci-C₄)alkyl group optionally substituted with one or more hydroxyl groups,

o or R₄ and R'₄ form, with the nitrogen atom to which they are attached, a saturated 5- to 7-membered heterocycle which may also comprise another heteroatom O or N, and which is optionally substituted with one or more (Ci-C₄)alkyl groups; particularly -N(R₄)(R'₄) represents a piperazino, piperidino or morpholino group optionally substituted with a (Ci-C₄)alkyl group such as methyl, preferably piperazino substituted with a (Ci-C₄)alkyl group such as methyl.

According to another advantageous embodiment of the invention, R₂ represents a hydroxyl, (hydroxy)(Ci-C₄)alkoxy, (di)(Ci-C₄)(alkyl)amino,

(di)hydroxy(Ci-C₄)alkylamino, or (Ci-C₄)alkoxycarbonyl(Ci-C₄)alkylamino group; preferably, R₂ represents a hydroxyl group, a propylamino radical, or a hydroxyethyloxy, ethoxy, or methoxycarbonylmethylamino -NHCH₂C0₂Me radical.

According to one particular embodiment of the invention, R₃ represents a hydrogen atom.

Preferably, p is 0.

According to one particular embodiment of the invention, R₆ represents a hydrogen atom, or a group chosen from a) (hydroxy)(Ci-C5)alkyl, b) carboxy(Ci- Cs)alkyl, c) (Ci-C5)alkoxycarbonyl(Ci-Cs)alkyl, d) hydroxy(Ci- C₄)alkylaminocarbonyl(Ci-C5)alkyl, e) hydroxy(Ci-C₄)alkyloxycarbonyl(Ci-

Cs)alkyl, f) heterocycle-C(0)-(Ci-C₅)alkyl with heterocycle comprising 6 ring members, being saturated, comprising 1 or 2 heteroatoms chosen from O and N and being optionally substituted with one or more (Ci-C₄)alkyl groups, such as piperazino, piperidino or morpholino, preferably f) represents an N-(C i - C₄)alkylpiperazinocarbonyl(Ci-C5)alkyl group.

More preferentially, R₆ represents a hydrogen atom or a group chosen from the groups:

-hydroxyethyloxycarbonylethyl,

-hydroxyethylaminocarbonylethyl,

-ethoxycarbonylethyl,

-N-methylpiperazinocarbonylethyl.

According to one particular embodiment of the invention, R₂ forms, with R₆ and the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, preferably saturated, heterocycle comprising 5 or 6 ring members:

• comprising one or more heteroatoms and/or groups chosen from -O-, -S-, -N(H)-, -N(R"₄)- with R"₄ as defined above, -C(O)-, -C(S)- and/or • optionally substituted with one or more radicals, which may be identical or different, chosen from i) hydroxyl, ii) C₁-C₄ (hydroxy)alkyl, iii) C₁-C₄ alkoxycarbonyl and iv) carboxy -COOH radicals;

more preferentially, R₂ and R₆ form, with the carbon atoms to which they are attached, a saturated 5- or 6-membered heterocycle comprising one or two heteroatoms and/or groups chosen from O, S, -N(H)-, -N(R"₄) with R"₄ as defined above, -C(O)-,

-C(S)- , preferably form a tetrahydropyran group.

According to another advantageous embodiment of the invention, n is 0 or 1. According to another advantageous embodiment of the invention, R₃ forms, with R₂ and the carbon atoms to which they are attached, an aromatic or non aromatic, saturated or unsaturated, preferably saturated, heterocycle comprising 5 or 6 ring members:

• comprising one or more heteroatoms and/or groups chosen from -0-, -S-, -N(H)-, -N(R"₄)- with R"₄ as defined above, -S(O)-, -S(0)₂-, -C(O)-, -

C(S)- and/or

more preferentially, R₂ and R₃ form, with the carbon atoms to which they are attached, a saturated 5- or 6-membered heterocycle comprising one or two heteroatoms and/or groups chosen from O, S, -N(H)-, -N(R"₄) with R"₄ as defined above, -C(O)-, -C(S)- such as O and/or C(O), preferably a tetrahydropyran group.

According to one particular embodiment of the invention, R'₂ represents a hydroxyl group, an ethoxy group or a hydroxyethyloxy group.

According to one particular embodiment of the invention, R’ represents a hydrogen atom.

According to another particular embodiment of the invention, R's represents a (Ci-C₄)alkyl group optionally substituted with one or more carboxy groups, such as carboxymethyl.

According to another advantageous embodiment of the invention, R’ ₃ forms, with R'₂ and the carbon atoms to which they are attached, an aromatic or non aromatic, saturated or unsaturated, preferably saturated, heterocycle comprising 5 or 6 ring members: • comprising one or more heteroatoms and/or groups chosen from -0-, -S-, -N(H)-, -N(R"₄)- with R"₄ as defined above, -S(O)-, -S(0)₂-, -C(O)-, - C(S)- and/or

more preferentially, R’₂ and R’₃ form, with the carbon atoms to which they are attached, a saturated 5- or 6-membered heterocycle comprising one or two heteroatoms and/or groups chosen from O, S, -N(H)-, -N(R"₄) with R"₄ as defined above, -C(O)-, -C(S)- such as O and/or C(O), even more preferentially form a tetrahydropyran-2-one group.

According to one advantageous variant, R'₆ represents a hydrogen atom or a (Ci-C₄)alkyl group such as methyl, preferably RV, represents a hydrogen atom.

Preferably, p’ is 0 or 1.

Preferably, m is 1.

According to another variant, R’₆ forms, with R’₂ and the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, preferably saturated, heterocycle comprising 5 or 6 ring members:

• comprising one or more heteroatoms and/or groups chosen from -O-, -S-, -N(H)-, -N(R"₄)- with R"₄ as defined above, -S(O)-, -S(0)₂-, -C(O)-, - C(S)- and/or

· optionally substituted with one or more radicals, which may be identical or different, chosen from i) hydroxyl, ii) Ci-C₄ (hydroxy)alkyl, iii) Ci-C₄ alkoxycarbonyl and iv) carboxy -COOH radicals;

more particularly, R’₂ and R>, form, with the carbon atoms to which they are attached, a saturated 5- or 6-membered heterocycle comprising one or two heteroatoms and/or groups chosen from O, S, -N(H)-, -N(R"₄), -C(O)-, -C(S)- such as O and/or C(O), preferably form a tetrahydropyran-2-one group.

According to another advantageous embodiment of the invention:

- R"i represents a hydroxyl group, - R"₂ represents a hydroxyl group,

- R” ₃ represents a hydrogen atom,

- R” ₆ represents a hydrogen atom,

- p” is 0.

According to one preferred embodiment, the oxidation coupler(s) of formula (IA), (I), (II) or (III) are chosen from the compounds (1) to (21), and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and the mixtures thereof:



According to one preferred embodiment of the invention, the oxidation coupler(s) are in particular chosen from the compounds (1), (2), (3), (4), (5), (6), (7), (8), (9), (13) and (17), even more preferentially from the compounds (1), (3), (5), (6), (7), (8) and (9), and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and the mixtures thereof.

Another subject of the present invention relates to the compounds (1), (2), (13) and (17) as described above and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and the mixtures thereof.

According to another preferred embodiment of the invention, one or more oxidation bases are applied to the keratin fibres during step(s) i) of the dyeing process according to the invention.

By way of example, the oxidation bases are chosen from para- phenylenediamines, bis(phenyl)alkylenediamines, para-aminophenols, ortho- aminophenols and heterocyclic bases, and the corresponding addition salts.

Among the para-phenylenediamines that may be mentioned are, for example, para-phenylenediamine, para-toluenediamine, 2-chloro-para- phenylenediamine, 2,3-dimethyl-para-phenylenediamine, 2,6-dimethyl-para- phenylenediamine, 2,6-diethyl-para-phenylenediamine, 2,5-dimethyl-para- phenylenediamine, N,N-dimethyl -para-phenylenediamine, N,N-diethyl-para- phenylenediamine, N,N-dipropyl -para-phenylenediamine, 4-amino-N,N-diethyl-3- methylaniline, N,N-bis(P-hydroxyethyl)-para-phenylenediamine, 4-N,N-bis(P- hydroxyethyl)amino-2-methylaniline, 4-N,N-bis(P-hydroxyethyl)amino-2- chloroaniline, 2-P-hydroxyethyl-para-phenylenediamine, 2-methoxymethyl-para- phenylenediamine, 2-fluoro-para-phenylenediamine, 2-isopropyl-para- phenylenediamine, N-(P-hydroxypropyl)-para-phenylenediamine, 2-hydroxymethyl - para-phenylenediamine, N,N-dimethyl-3-methyl-para-phenylenediamine, N-ethyl-N-

(P-hydroxyethyl)-para-phenylenediamine, N-(p,y-dihydiOxypropyl /-para- phenylenediamine, N - (4’ -aminophenyl) -para-phenylenediamine, N -phenyl-para- phenylenediamine, 2-P-hydroxyethyloxy-para-phenylenediamine, 2-b- acetylaminoethyloxy-para-phenylenediamine, N-(P-methoxyethyl)-para- phenylenediamine, 4-aminophenylpyrrolidine, 2-thienyl-para-phenylenediamine, 2-b- hydroxyethylamino-5-aminotoluene and 3-hydroxy- 1 -(4’ -aminophenyl)pyrrolidine, and the corresponding addition salts with an acid.

Among the para-phenylenediamines mentioned above, para- phenylenediamine, para-toluenediamine, 2-isoprop yl-para-phenylenediamine, 2-b- hydroxyethyl-para-phenylenediamine, 2^-hydroxyethyloxy-para-phenylenediamine, 2,6-dimethyl-para-phenylenediamine, 2,6-diethyl-para-phenylenediamine, 2,3- dimethyl-para-phenylenediamine, N,N-bis(b-hydroxyethyl)-para-phenylenediamine, 2-chloro-para-phenylenediamine and 2^-acetylaminoethyloxy-para- phenylenediamine, and the corresponding addition salts with an acid, are particularly preferred.

Among the bis(phenyl)alkylenediamines that may be mentioned, for example, are N,N'-bis^-hydroxyethyl)-N,N'-bis(4'-aminophenyl)-l,3- diaminopropanol, N,N'-bis^-hydroxyethyl)-N,N'-bis(4'- aminophenyl)ethylenediamine, N,N'-bis(4-aminophenyl)tetramethylenediamine,

N,N'-bis^-hydroxyethyl)-N,N'-bis(4-aminophenyl)tetramethylenediamine, N,N'- bis(4-methylaminophenyl)tetramethylenediamine, N,N'-bis(ethyl)-N,N'-bis(4'-amino- 3'-methylphenyl)ethylenediamine and 1 ,8-bis(2,5-diaminophenoxy)-3,6-dioxaoctane, and the corresponding addition salts.

Among the para-aminophenols that are mentioned are, for example, para- aminophenol, 4-amino-3-methylphenol, 4-amino-3-fluorophenol, 4-amino-3- chlorophenol, 4-amino-3-hydroxymethylphenol, 4-amino-2-methylphenol, 4-amino- 2-hydroxymethylphenol, 4-amino-2-methoxymethylphenol, 4-amino-2- aminomethylphenol, 4-amino-2-(b-hydroxyethylaminomethyl)phenol and 4-amino-2- fluorophenol, and the corresponding addition salts with an acid.

Among the ortho-aminophenols that may be mentioned, for example, are 2- aminophenol, 2-amino-5-methylphenol, 2-amino-6-methylphenol and 5-acetamido-2- aminophenol, and the corresponding addition salts.

Among the heterocyclic bases that may be mentioned, for example, are pyridine, pyrimidine and pyrazole derivatives.

Among the pyridine derivatives that may be mentioned are the compounds described, for example, in patents GB 1 026 978 and GB 1 153 196, for example 2,5- diaminopyridine, 2-(4-methoxyphenyl)amino-3-aminopyridine and 3,4- diaminopyridine, and the corresponding addition salts. Other pyridine oxidation bases that are useful in the present invention are the 3-aminopyrazolo[l,5-a]pyridine oxidation bases or the corresponding addition salts described, for example, in patent application FR 2 801 308. Examples that may be mentioned include pyrazolo[l,5-a]pyrid-3-ylamine, 2-acetylaminopyrazolo[l,5- a]pyrid-3-ylamine, 2-(morpholin-4-yl)pyrazolo[l,5-a]pyrid-3-ylamine, 3- aminopyrazolo[ 1 ,5-a]pyridine-2-carboxylic acid, 2-methoxypyrazolo[ 1 ,5-a]pyrid-3- ylamine, (3-aminopyrazolo[l,5-a]pyrid-7-yl)methanol, 2-(3-aminopyrazolo[l,5- a]pyrid-5-yl)ethanol, 2-(3-aminopyrazolo[l,5-a]pyrid-7-yl)ethanol, (3- aminopyrazolo[l,5-a]pyrid-2-yl)methanol, 3,6-diaminopyrazolo[l,5-a]pyridine, 3,4- diaminopyrazolo[l,5-a]pyridine, pyrazolo[l,5-a]pyridine-3, 7-diamine, 7-(morpholin- 4-yl)pyrazolo[l,5-a]pyrid-3-ylamine, pyrazolo[l,5-a]pyridine-3, 5-diamine, 5- (morpholin-4-yl)pyrazolo[ 1 ,5-a]pyrid-3-ylamine, 2- [(3-aminopyrazolo[ 1 ,5-a]pyrid-5- yl)(2-hydroxyethyl)amino]ethanol, 2-[(3-aminopyrazolo[l,5-a]pyrid-7-yl)(2- hydroxyethyl)amino] ethanol, 3-aminopyrazolo[l,5-a]pyridin-5-ol, 3- aminopyrazolo[l,5-a]pyridin-4-ol, 3-aminopyrazolo[l,5-a]pyridin-6-ol, 3- aminopyrazolo[l,5-a]pyridin-7-ol, 2-P-hydroxyethoxy-3-aminopyrazolo[l,5- a]pyridine and 2-(4-dimethylpiperazinium-l-yl)-3-aminopyrazolo[l,5-a]pyridine, and the corresponding addition salts.

More particularly, the oxidation bases that are useful in the present invention are chosen from 3-aminopyrazolo[l,5-a]pyridines and are preferably substituted on carbon atom 2 with:

a) a (di)(Ci-C₆)(alkyl)amino group, said alkyl group possibly being substituted with at least one hydroxyl, amino or imidazolium group;

b) an optionally cationic 5- to 7-membered heterocyclo alkyl group comprising from 1 to 3 heteroatoms, optionally substituted with one or more (Ci-

C_fjalkyl groups such as a di(Ci-C₄)alkylpiperazinium group; or

c) a (Ci-C₆)alkoxy group optionally substituted with one or more hydroxyl groups, such as a b-hydroxyalkoxy group, and the corresponding addition salts.

Among the pyrimidine derivatives that may be mentioned are the compounds described, for example, in patents DE 2359399; JP 88-169571; JP OS- 63124; EP 0770375 or patent application WO 96/15765, such as 2, 4,5,6- tetraaminopyrimidine, 4-hydroxy-2,5,6-triaminopyrimidine, 2-hydroxy-4,5,6- triaminopyrimidine, 2,4-dihydroxy-5,6-diaminopyrimidine, 2,5,6-triaminopyrimidine and the addition salts thereof and the tautomeric forms thereof, when a tautomeric equilibrium exists.

Among the pyrazole derivatives that may be mentioned are the compounds described in patents DE 3843892 and DE 4133957 and patent applications WO 94/08969, WO 94/08970, FR-A-2 733 749 and DE 195 43 988, for instance 4,5- diamino- 1 -methylpyrazole, 4,5-diamino- 1 -(P-hydroxyethyl)pyrazole, 3,4- diaminopyrazole, 4,5-diamino- l-(4'-chlorobenzyl)pyrazole, 4,5-diamino- 1,3- dimethylpyrazole, 4,5-diamino-3-methyl- l-phenylpyrazole, 4,5-diamino- l-methyl-3- phenylpyrazole, 4-amino-l,3-dimethyl-5-hydrazinopyrazole, 1 -benzyl-4, 5-diamino- 3-methylpyrazole, 4,5-diamino-3-/er/-butyl- 1 -methylpyrazole, 4,5-diamino- 1 -tert- butyl-3-methylpyrazole, 4,5-diamino- l-(P-hydroxyethyl)-3-methylpyrazole, 4,5- diamino- l-ethyl-3-methylpyrazole, 4,5-diamino- l-ethyl-3-(4'- methoxyphenyl)pyrazole, 4,5-diamino- l-ethyl-3-hydroxymethylpyrazole, 4,5- diamino-3-hydroxymethyl- 1 -methylpyrazole, 4,5-diamino-3-hydroxymethyl- 1 - isoprop ylpyrazole, 4,5-diamino-3-methyl-l-isopropylpyrazole, 4-amino-5-(2'- aminoethyl)amino-l,3-dimethylpyrazole, 3,4,5-triaminopyrazole, l-methyl-3,4,5- triaminopyrazole, 3,5-diamino-l-methyl-4-methylaminopyrazole and 3,5-diamino-4- (P-hydroxyethyl)amino-l -methylpyrazole, and the corresponding addition salts. Use may also be made of 4,5-diamino- l-(P-methoxyethyl)pyrazole.

A 4,5-diaminopyrazole will preferably be used and even more preferentially

4,5-diamino- l-(P-hydroxyethyl)pyrazole and/or a corresponding salt.

The pyrazole derivatives that may also be mentioned include diamino-N,N- dihydropyrazolopyrazolones and in particular those described in patent application FR-A-2 886 136, such as the following compounds and the corresponding addition salts: 2,3-diamino-6,7-dihydro-lH,5H-pyrazolo[l,2-a]pyrazol-l-one, 2-amino-3- ethylamino-6,7 -dihydro- lH,5H-pyrazolo[ 1 ,2-a]pyrazol- 1 -one, 2-amino-3- isopropylamino-6, 7-dihydro- lH,5H-pyrazolo[l,2-a]pyrazol-l-one, 2-amino-3-

(pyrrolidin-l-yl)-6, 7-dihydro- lH,5H-pyrazolo[l,2-a]pyrazol-l-one, 4, 5-diamino- 1,2- dimethyl- 1 ,2-dihydropyrazol-3-one, 4,5-diamino- 1 ,2-diethyl- 1 ,2-dihydropyrazol-3- one, 4, 5-diamino- l,2-bis(2-hydroxyethyl)-l,2-dihydropyrazol-3-one, 2-amino-3-(2- hydroxyethyl)amino-6, 7-dihydro- lH,5H-pyrazolo[l,2-a]pyrazol-l-one, 2-amino-3- dimethylamino-6, 7-dihydro- lH,5H-pyrazolo[l,2-a]pyrazol-l-one, 2,3-diamino- 5,6,7,8-tetrahydro-lH,6H-pyridazino[l,2-a]pyrazol-l-one, 4-amino-l,2-diethyl-5- (pyrrolidin-l-yl)-l,2-dihydropyrazol-3-one, 4-amino-5-(3-dimethylaminopyrrolidin- l-yl)-l, 2-diethyl- l,2-dihydropyrazol-3-one and 2,3-diamino-6-hydroxy-6,7-dihydro- lH,5H-pyrazolo[ 1 ,2-a]pyrazol- 1 -one.

Use will preferably be made of 2, 3-diamino-6, 7-dihydro- lH,5H- pyrazolo[l,2-a]pyrazol-l-one and/or a corresponding salt.

Heterocyclic bases that will preferably be used are 4,5-diamino- 1-(b- hydroxyethyl)pyrazole and/or 2, 3-diamino-6, 7-dihydro- lH,5H-pyrazolo[ 1 ,2- a]pyrazol-l-one and/or a corresponding salt.

According to one particular embodiment of the invention, one or more additional oxidation couplers as described below, different from the compounds of formulae (IA), (I), (II) and/or (III), and also from the geometric or optical isomers thereof, the tautomers thereof, the organic or mineral acid or base salts thereof or the solvates thereof, can be applied during step(s) i) of the dyeing process according to the invention.

Among these additional oxidation couplers, mention may be made in particular of meta-phenylenediamines, meta-aminophenols, meta-diphenols, naphthalene -based coupling agents and heterocyclic coupling agents, and also the corresponding addition salts.

Mention may for example be made of l,3-dihydroxybenzene, 1,3- dihydroxy-2-methylbenzene, 4-chloro- 1 ,3-dihydroxybenzene, 2,4-diamino- 1-(b- hydroxyethyloxy)benzene, 2-amino-4-^-hydroxyethylamino)-l-methoxybenzene, l,3-diaminobenzene, l,3-bis(2,4-diaminophenoxy)propane, 3-ureidoaniline, 3- ureido- l-dimethylaminobenzene, sesamol, l^-hydroxyethylamino-3,4- methylenedioxybenzene, a-naphthol, 2-methyl- l-naphthol, 6-hydroxyindole, 4- hydroxyindole, 4-hydroxy-N-methylindole, 2-amino-3-hydroxypyridine, 6- hydroxybenzomorpholine, 3,5-diamino-2,6-dimethoxypyridine, 1-N-(b- hydroxyethyl)amino-3,4-methylenedioxybenzene, 2,6-bis^- hydroxyethylamino)toluene, 6-hydroxyindoline, 2,6-dihydroxy-4-methylpyridine, 1- H-3-methylpyrazol-5-one, l-phenyl-3-methylpyrazol-5-one, 2,6- dimethylpyrazolo[l,5-b]-l, 2, 4-triazole, 2, 6-dimethyl[3,2-c]-l, 2, 4-triazole and 6- methylpyrazolo[l,5-a]benzimidazole, 2-methyl-5-aminophenol, 5-N-(b- hydroxyethyl)amino-2-methylphenol, 3-aminophenol and 3-amino-2-chloro-6- methylphenol, the corresponding addition salts with an acid and the corresponding mixtures. According to another preferred embodiment of the invention, the process for dyeing keratin fibres, in particular human keratin fibres such as the hair, also comprises at least a step of applying ii) to said keratin fibres an oxidizing cosmetic composition comprising one or more chemical oxidizing agents, preferably chosen from hydrogen peroxide, urea peroxide, alkali metal bromates, persalts such as perborates and persulfates, peracids, and oxidase enzymes (with the possible cofactors thereof), among which mention may be made of peroxidases, 2-electron oxidoreductases such as uricases, and 4-electron oxygenases, for instance laccases; more preferentially, the chemical oxidizing agent is hydrogen peroxide;

it being understood that, between step(s) i) and step(s) ii), said fibres may be rinsed, and/or washed and then optionally dried.

Preferably, the process for dyeing keratin fibres, in particular human keratin fibres such as the hair, comprises at least i) a step of applying to said keratin fibres one or more oxidation couplers chosen from the compounds of formula (IA), (I), (II) or (III) as defined above, and one or more oxidation bases as defined above; and optionally at least a step of applying ii) to said keratin fibres an oxidizing cosmetic composition comprising one or more chemical oxidizing agents as described above, the chemical oxidizing agent more preferentially being hydrogen peroxide.

According to this preference, when step(s) ii) are carried out, it is understood that, between step(s) i) and step(s) ii), said fibres can be rinsed, and/or washed and then optionally dried.

Preferably, the compound(s) of formula (IA), (I), (II) or (III) according to the invention are applied for a leave-on time of between 1 and 75 minutes, preferably between 5 and 60 minutes, and even more preferentially between 10 and 55 minutes.

The compound(s) of formula (IA), (I), (II) or (III) according to the invention are generally applied to the keratin fibres at ambient temperature, preferably between 25 and 55°C.

Preferably, steps i) and ii) are carried out sequentially.

For the purposes of the present invention, the term "sequentially" is intended to mean that step(s) ii) are carried out before or after step(s) i), that is to say as pre treatment or post-treatment, preferably as post-treatment.

According to one variant of the invention, the application to said fibres: of the oxidation coupler(s) as described above;

of the chemical oxidizing agent(s) as described above;

of the optional oxidation base(s);

is simultaneous.

According to this variant, a ready-to-use cosmetic composition can be pre prepared, resulting from the mixing of a cosmetic composition comprising one or more oxidation couplers chosen from the compounds of formula (IA), (I), (II) or (III) as defined above and optionally one or more oxidation bases, and of an oxidizing cosmetic composition comprising one or more chemical oxidizing agents as defined above, so as to then be applied to said fibres.

According to this variant of the invention, said ready-to-use cosmetic composition can be applied for a leave-on time of between 1 and 75 minutes, preferably between 5 and 60 minutes, and even more preferentially between 10 and 55 minutes, and generally at ambient temperature, preferably between 25 and 55°C.

The term“simultaneously” is intended to mean that the compound(s) of formula (IA), (I), (II) or (III) as defined above, the chemical oxidizing agent(s) as defined above and optionally the oxidation base(s) as described above are applied to said keratin fibres at the same time. According to one particular embodiment of the invention, one or more direct dyes, chosen from those commonly used by those skilled in the art, can be applied to the keratin fibres during step i) of the dyeing process according to the invention.

Composition

The present invention also relates to a cosmetic composition comprising: one or more oxidation couplers chosen from the compounds of formula (IA), (I), (II) or (III) as defined above; preferably the oxidation coupler(s) are chosen from the compounds (1) to (21) as described above; and - one or more oxidation bases.

According to a preferred embodiment of the invention, the cosmetic composition comprises: one or more oxidation couplers chosen from the compounds (1), (2), (3), (4), (5), (6), (7), (8), (9), (13) and (17), more preferentially chosen from the compounds (1), (3), (5), (6), (7), (8) and (9), and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and the mixtures thereof; and one or more oxidation bases.

Another subject of the invention is a composition, in particular a cosmetic composition, comprising at least one compound chosen from the compounds (1), (2), (13) and (17) as described above and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and the mixtures thereof.

Preferably, the content of the oxidation coupler(s), chosen from the compounds of formula (IA), (I), (II) or (III), in the composition according to the invention is between 0.001% and 20% by weight, more preferentially between 0.005% and 6% by weight, relative to the total weight of the composition.

As indicated above, the cosmetic composition according to the invention also comprises at least one oxidation base, which can be chosen from those described above.

The oxidation base(s) each advantageously represent 0.001% to 10% by weight relative to the total weight of the composition, and preferably from 0.005% to 5% by weight relative to the total weight of the composition according to the invention.

According to one particular embodiment of the invention, the cosmetic composition according to the invention also comprises at least one additional oxidation coupler as described above, different from the compounds of formulae (IA), (I), (II) and/or (III), and also from the geometric or optical isomers thereof, the tautomers thereof, the organic or mineral acid or base salts thereof or the solvates thereof according to the invention.

Preferably, when they are present, the additional oxidation coupler(s), different from the compounds of formulae (IA), (I), (II) and/or (III), and also from the geometric or optical isomers thereof, the tautomers thereof, the organic or mineral acid or base salts thereof or the solvates thereof, each advantageously represent 0.001% to 10% by weight, more preferentially 0.005% to 5% by weight, relative to the total weight of the composition according to the invention.

According to another preferred embodiment of the invention, the composition also comprises one or more chemical oxidizing agents, preferably chosen from hydrogen peroxide, urea peroxide, alkali metal bromates, persalts such as perborates and persulfates, peracids, and oxidase enzymes (with the possible cofactors thereof), in particular peroxidases, 2-electron oxidoreductases such as uricases, and 4-electron oxygenases, for instance laccases; and more preferentially the chemical oxidizing agent is hydrogen peroxide.

Preferably, when they are present, the total content of the chemical oxidizing agent(s) present in the composition is strictly greater than 0.1% by weight relative to the total weight of the composition according to these variants.

According to another variant of the invention, the cosmetic composition is a ready- to-use cosmetic composition, especially for dyeing keratin fibres, in particular human keratin fibres such as the hair, which results from the mixing of a cosmetic composition comprising one or more oxidation couplers chosen from the compounds of formula (IA), (I), (II) or (III) as defined above and of an oxidizing cosmetic composition comprising one or more chemical oxidizing agents.

According to another variant of the invention, the composition comprising one or more oxidation couplers chosen from the compounds of formula (IA), (I), (II) or (III) as defined above and one or more oxidation bases is free of chemical oxidizing agent.

The expression“free of chemical oxidizing agent” is intended to mean that the composition does not comprise any chemical oxidizing agent, or that the total content of the chemical oxidizing agent(s) present in the composition is less than or equal to 0.1% by weight relative to the total weight of the composition according to this variant.

Preferably, the composition also comprises a medium that is cosmetically acceptable for dyeing keratin fibres.

A medium suitable for dyeing keratin fibres generally comprises water or a mixture of water and at least one organic solvent such as, for example, branched or unbranched Ci-C₄ lower alcohols, such as ethanol and isopropanol; polyols and polyol ethers, such as 2-butoxyethanol, propylene glycol, propylene glycol monomethyl ether, diethylene glycol monoethyl ether and monomethyl ether, and glycerol, and also aromatic alcohols such as benzyl alcohol or phenoxyethanol, and mixtures thereof.

Preferably, the pH of the cosmetic composition according to the invention is between 7.5 and 12, preferably between 8 and 11 and even more preferentially between 9 and 10.

The pH of the cosmetic composition according to the invention may optionally be adjusted to the desired value by means of one or more acidifying agents and/or one or more basifying agents.

Among the acidifying agents that may be mentioned, by way of example, are mineral or organic acids, for instance hydrochloric acid, orthophosphoric acid or sulfuric acid, carboxylic acids, for instance acetic acid, tartaric acid, citric acid and lactic acid, and sulfonic acids.

Among the basifying agents, examples that may be mentioned include aqueous ammonia, alkali metal carbonates, alkanolamines, such as mono-, di- and triethanolamines and derivatives thereof, sodium hydroxide, potassium hydroxide and the compounds of formula (VI) below:

R_aR_bN-Z-NR_cR_d ;

in which Z is a linear or branched (Ci-C₆)alkylene group optionally substituted in particular with one or more hydroxyl or amino groups, preferably Z = propylene, optionally substituted with a hydroxyl group or a Ci-C₄ alkyl radical; R_a, R_b, R_c and R_d, which may be identical or different, represent a hydrogen atom or a Ci-C₄ alkyl or C₁-C₄ hydroxyalkyl radical.

Advantageously, the cosmetic composition according to the invention may also comprise at least one additive chosen from direct dyes, fragrances, surfactants (cationic, anionic, non-ionic or amphoteric), sequestering agents, polymers, ceramides, silicones, preservatives, pearlescent agents or opacifiers, vitamins or pro vitamins.

When they are present, the total content of the additive(s) present in the composition is between 0.01% and 20% by weight relative to the total weight of the composition according to the invention.

The cosmetic composition according to the invention may be present in various forms, such as in the form of liquids, creams, gels, mousses or any other form that is suitable for dyeing keratin fibres, and especially human hair. A subject of the present invention is also a multicompartment dyeing device or kit, comprising a first compartment containing one or more oxidation couplers chosen from the compounds of formula (IA), (I), (II) or (III) as defined above, and a second compartment comprising one or more chemical oxidizing agents as defined above.

According to one preferred embodiment of the invention, the multicompartment device according to the invention comprises a first compartment containing the cosmetic composition according to the invention as defined above, and a second compartment comprising an oxidizing cosmetic composition containing one or more chemical oxidizing agents as defined above.

According to one variant of the invention, the device according to the invention comprises one compartment containing a ready-to-use cosmetic composition as defined above.

The examples that follow serve to illustrate the invention without, however, being limiting in nature.

EXAMPLES:

Example 1 : Chemical syntheses

Example 1.1: synthesis of 7-(propylamino)-3,4-dihydro-2H-chromen-5-ol

(1)

Commercial 3,4-dihydro-2H-chromene-5,7-diol (1 g; 6.02 mmol) and propylamine (356 mg; 6.02 mmol) in toluene are introduced into a round-bottomed flask fitted with the appropriate glassware. The reaction medium is refluxed for 3 hours.

The toluene is eliminated in a rotary evaporator until a crude is obtained that is purified by silica column chromatography (eluent: EtO Ac/heptane 2/8 to 5/5 in 10 CV). The crystals obtained are finally taken up in heptane, filtered and vacuum-dried at 40°C to obtain a beige-coloured product. The spectroscopic and spectrometric analyses are in accordance with the structure of the expected product (1).

Example 1 2 synthesis of (5,7-dihydroxy-2-oxo-3,4-dihydro-2H-chromen- 3-yl)acetic acid (2)

Phloroglucinol (2.52 g, 20 mmol) and itaconic acid (2.6 g, 20 mmol) in toluene are introduced into a round-bottomed flask fitted with the appropriate glassware (Dean-Stark apparatus). The reaction medium is refluxed for 30 minutes. 5 g of Amberlyst 15 are then added. The reaction medium is then left at reflux for a further l6h. After cooling of the reaction medium, the latter is filtered in order to remove the resin. The toluene is then eliminated in a rotary evaporator until a crude is obtained that is purified by silica column chromatography (eluent: EtO Ac/petroleum ether 1/1). A white-coloured product is obtained. The spectroscopic and spectrometric analyses are in accordance with the structure of the expected product (2).

Example 1.3: Synthesis of 5,7-dihydroxy-3,4-dihydro-2H-chromen-2-one

(3)

Acrylic acid (5.71 g, 79.3 mmol), 120 ml of toluene and 40 ml of THF, then phloroglucinol (10 g, 79.3 mmol) and 15 g of Amberlyst 15 are introduced into a round-bottomed flask fitted with the appropriate glassware (Dean-Stark apparatus). The reaction medium is refluxed for 16 hours. After cooling of the reaction medium, the latter is filtered in order to remove the resin. The toluene is then eliminated in a rotary evaporator until a crude is obtained that is purified by silica column chromatography (eluent: dichloromethane/methanol = 150/1). The product obtained is then recrystallized from an ethyl acetate/petroleum ether mixture. The expected product is white in colour.

The spectroscopic and spectrometric analyses are in accordance with the structure of the expected product (3).

Example 1. 4i Synthesis of 5-hydroxy-3,4,9,l0-tetrahydro-2H,8H- pyrano[2,3-f]chromene-2,8-dione (4)

Acrylic acid (12.57 g, 174.5 mmol), 120 ml of toluene and 40 ml of THF, then phloroglucinol (10 g, 79.3 mmol) and 12 g of Amberlyst 15 are introduced into a round-bottomed flask fitted with the appropriate glassware (Dean-Stark apparatus). The reaction medium is refluxed for 6 hours. After cooling of the reaction medium, the latter is filtered in order to remove the resin. The toluene is then eliminated in a rotary evaporator until a reaction crude is obtained. The product obtained is then taken up in a dichloromethane/methanol mixture. A further precipitate is obtained under these conditions. Said precipitate is filtered off and cleaned with a small amount of methanol. After drying, the expected product is white in colour. The spectroscopic and spectrometric analyses are in accordance with the structure of the expected product (4).

Example 1.5: synthesis of 5-[(2-hydroxyethyl)amino]-3,4-dihydro-2H- chromen-7-ol (17)

Commercial phloroglucinol (1 g; 6.02 mmol) and ethanolamine (356 mg; 6.02 mmol) in tetrahydrofuran are introduced into a round-bottomed flask fitted with the appropriate glassware. The reaction medium is left at ambient temperature (AT) for 16 hours.

The toluene is eliminated in a rotary evaporator until a crude is obtained that is purified by silica column chromatography. The product 9 obtained is then reacted in the presence of l,3-dibromopropane and of an aqueous-alcoholic solution of sodium hydroxide at 80°C for 8 hours. The reaction medium is subsequently concentrated and then neutralized with a 1N HC1 solution. An extraction of the aqueous phase in the presence of dichloromethane made it possible to obtain, after evaporation, an oily residue which was then subjected to purification by silica column chromatography. The product is beige in colour. The spectroscopic and spectrometric analyses are in accordance with the structure of the expected product (17).

Example 1.6: synthesis of 5-hydroxy-7-(2-hydroxyethoxy)-3,4-dihydro-2H- chromen-2-one (13)

The compound (3) (5.4 g; 30 mmol) and benzyl chloride (3.8 g, 30 mmol) in 80 ml of acetonitrile are introduced into a round-bottomed flask fitted with the appropriate glassware. Sodium bicarbonate (5 g, 60 mmol) then sodium iodide (1 g) are then added. The reaction medium is left at reflux for 6 hours.

The reaction medium is returned to ambient temperature and 300 ml of water are added. The aqueous phase is then extracted several times with ethyl acetate. The organic phases are then combined, dried over sodium sulfate, filtered and then concentrated under vacuum. The resulting reaction crude is then purified by silica column chromatography (petroleum ether/ethyl acetate: 5/1). The product (l3-a) is thus obtained (white solid). The spectroscopic and spectrometric analyses are in accordance with the structure of the expected product (l3-a). The latter ((l3-a), 1.2 g, 4.4 mmol) is then dissolved in DMF (20 ml) at 0°C. Potassium carbonate (1.2 g, 8.7 mmol) and the iodinated derivative 12 (2.36 g, 9 mmol) are added one after the other. The reaction medium is subsequently returned to ambient temperature and then left to stir at ambient temperature (AT) for 48 hours. After reaction, 100 ml of water are then added and the aqueous phase is then extracted several times with ethyl acetate. The organic phases are then combined, dried over sodium sulfate, filtered and then concentrated under vacuum. The resulting reaction crude is then purified by silica column chromatography (petroleum ether/ethyl acetate: 20/1) to give the compound (l3-b) (white solid). The analyses are in accordance with the structure of the expected product (l3-b). The third and final step of the reaction consisted in dissolving, in 40 ml of THF, 1.37 g of the compound (l3-b) previously obtained in the presence of 0.2 g of Pd/C at 10%. The mixture is then hydrogenated at ambient temperature (AT) for 16 hours. After reaction, filtration of the reaction medium is then carried out. The resulting reaction crude is then purified by silica column chromatography (dichloromethane/methanol: 5/1) to give the compound (13) (white solid). The analyses are in accordance with the structure of the expected product. The spectroscopic and spectrometric analyses are in accordance with the structure of the expected product (13).

Example 2: Colourations

Composition (A) according to the present invention was prepared from the ingredients of which the contents are indicated, as weight percentage of active material relative to the total weight of composition, in the table below.

Composition (A) was prepared with each of the oxidation bases below.

a) Procedure

At the time of use, each of compositions (Al) to (A7) comprising one of the oxidation couplers, chosen from the compounds (1), (3), (5), (6), (7), (8) and (9) as described above, is mixed with a 20-volume solution of aqueous hydrogen peroxide (6% by weight) according to a 1:1 ratio. The final pH of each of the mixtures is equal to 9.5.

Each mixture thus obtained is applied to a lock of grey hair containing 90% grey hairs. After a leave-on time of 45 minutes, the locks are rinsed, washed with a standard shampoo and then rinsed again. The locks are then dried. b) Results The shades observed for each of compositions (Al) to (A7) comprising one of the oxidation couplers (1), (3), (5), (6), (7), (8) and (9) according to the invention are grouped together in the table below.

The locks of hair treated according to the process of the invention exhibit intense, chromatic colourations which are unselective along the fibre.

The locks of hair treated according to the process of the invention also exhibit a broad range of light or dark shades, from violet to brown.

Claims

1. Process for dyeing keratin fibres, in particular human keratin fibres such as the hair, comprising at least i) a step of applying to said keratin fibres one or more oxidation couplers chosen from the compounds of formula (IA) below; and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and mixtures thereof:

in which formula (IA):

z and q, which may be identical or different, equal 0 or 1, it being understood that z and q cannot simultaneously denote 0;

t represents an integer equal to 0, 1 or 2, it being understood that, when t is 2, then the R_SA radicals may be identical or different;

R_IA and R_2A, which may be identical or different, represent:

• a hydroxyl radical,

• an amino radical -NH₂, or

• an -N(R_4A)(R'_4A) radical in which R_4A and R'_4A, which may be identical or different, represent:

o a hydrogen atom,

o a (Ci-C₆)alkyl or (C₂-C₆)alkenyl group, optionally substituted with one or more groups, which may be identical or different, chosen from i) hydroxyl, ii) amino -NH₂, iii) carboxy -COOH, iv) (Ci-C₄)alkoxycarbonyl, v) hydroxysulfonyl -SO₃H, vi) dihydroxyphosphonyl -P(0)(OH)₂, o or R_4A and R'_4A can form, with the nitrogen atom to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, 5- to 7-membered heterocycle:

^■ optionally comprising one or more heteroatoms and/or additional groups chosen from: -0-, -S-, -NH-, -N(R"_4A)- where R"_4A represents a (Ci-C₄)alkyl, -S(O)-, -S(0)₂-, -C(O)- or -C(S)- group and/or

- R5_A represents i) a linear or branched Ci-C₆ alkyl radical optionally substituted with one or more groups, which may be identical or different, chosen from:

• hydroxyl,

• amino -NH₂,

· carboxy COOH

• (Ci-C₄)alkoxycarbonyl, or

ii) a phenyl radical optionally substituted with one or more halogen atoms such as chlorine and/or bromine, and/or with one or more hydroxyl groups; R_6A represents:

· a hydrogen atom,

more preferentially R_6A represents a hydrogen atom, -C(0)-N(R'"_4AK or -C(0)-0R'"_{4 \}, with R"'_4A representing an ethyl or hydroxyethyl group;

R_2A and R_6A, or R_2A and R_3A can form, with the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated heterocycle comprising from 5 to 7 ring members:

• optionally comprising one or more heteroatoms and/or additional groups chosen from -0-, -S-, -NH-, -N(R"_4A)- with R"_4A as defined above, -

S(O)-, -S(0)₂-, -C(O)-, -C(S)- or a combination thereof such as - OC(O)-, -C(0)0- and/or

Y denotes a -(CH₂)- or -CH(Rsc)- or -CO- diradical with Rsc having the same definition as Rs_A mentioned above when Y is bonded by two single bonds, or Y denotes a =(CH)- or =C(Rsc)- triradical with Rs_C as defined above when Y is bonded by 1 single bond and 1 double bond;

understood that X and Y cannot simultaneously denote -CO-;

R_SA and R_SB, or R_SB and Rsc can form, with the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated heterocycle comprising from 5 to 7 ring members:

• optionally comprising one or more heteroatoms and/or additional groups chosen from -0-, -S-, -NH-, -N(R"_4A)- with R"_4A as defined above, - S(O)-, -S(0)₂-, -C(O)-, -C(S)- and/or

denotes a single bond or a double bond.

2. Process according to the preceding claim, characterized in that the compounds of formula (IA) are chosen from the compounds of formula (I), (II) or (III) below; and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and the mixtures thereof:

p represents an integer equal to 0, 1, 2 or 3, it being understood that, when p is 2 or 3, then the R₅ radicals may be identical or different;

p' and p", which may be identical or different, are equal to 0, 1 or 2, it being understood that, when p’ is 2, then the R'₅ radicals may be identical or different, or that, when p” is 2, then the R"s radicals may be identical or different;

• a hydroxyl radical,

• an amino radical -NH₂, or

o a hydrogen atom,

o a (Ci-C₆)alkyl or (C₂-C₆)alkenyl group, optionally substituted with one or more groups, which may be identical or different, chosen from i) hydroxyl, ii) amino -NH₂, iii) carboxy -COOH, iv) (Ci-C₄) alkoxycarbonyl, v) hydroxysulfonyl -SO₃H, vi) dihydroxyphosphonyl -P(0)(OH)₂,

o or R₄ and R'₄ can form, with the nitrogen atom to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, 5- to 7-membered heterocycle: ^■ optionally comprising one or more heteroatoms and/or additional groups chosen from -0-, -S-, -NH-, -N(R"₄)- where R"₄ represents a (Ci-C₄)alkyl, -S(O)-, -S(0)₂-, -C(O)- or -C(S)- group and/or

^■ optionally substituted with one or more radicals, which may be identical or different, chosen from i) hydroxyl, ii) Ci-C₄

(hydroxy)alkyl, iii) Ci-C₄ alkoxycarbonyl and iv) carboxy -COOH radicals;

R₃, R'₃ and R"₃, which may be identical or different, represent a hydrogen atom, a halogen atom, a carboxy -COOH radical, or a Ci-C₄ alkoxy radical optionally substituted with one or more hydroxyl groups;

R₅ represents i) a linear or branched Ci-C₆ alkyl radical optionally substituted with one or more groups, which may be identical or different, chosen from:

• hydroxyl,

· amino -NH₂, or

• hydroxyl,

• carboxy -COOH,

• halogen atom(s) such as bromine and/or chlorine,

• Ci-C₄ alkoxycarbonyl, or

• a hydrogen atom;

optionally interrupted with one or more heteroatoms and/or groups chosen from O, S, NH, N(R'"₄), C(O), and combinations thereof such as -O-C(O)-, -C(0)-0-, -NH-C(O)-, -C(0)-NH-, -C(0)-N(R'"₄)-, -C(O)-

OR'"₄, with R'"₄ representing a (Ci-C₄)alkyl group optionally substituted with a hydroxyl;

more preferentially R₆ represents a hydrogen atom, -C(0)-N(R'"₄)-, or -C(0)-0R'"₄, with R'"₄ representing an ethyl or hydroxyethyl group; - R'₆ and R'V,, which may be identical or different, are as defined for R₆, preferably R'₆ and R'V, represent a hydrogen atom;

R₂ and R₆ or R₂ and R₃, and/or R'₂ and RV, or R'₂ and RV, and/or R"₂ and R"₃ can form, with the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, heterocycle comprising from 5 to 7 ring members:

• optionally comprising one or more heteroatoms and/or additional groups chosen from -0-, -S-, -NH-, -N(R"₄)- with R"₄ as defined above, -S(O)-, -S(0)₂-, -C(O)-, -C(S)- and/or

when p' and/or p" is (are) equal to 2, the two RV radicals and/or the two R'V radicals can form, with the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, (hetero)cycle comprising 5 or 6 ring members:

• optionally comprising one or more heteroatoms and/or additional groups chosen from -O-, -S-, -NH-, -N(R"₄)- with R"4 as defined above, -S(O)-, -S(0)₂-, -C(O)-, -C(S)- and/or

3. Process according to the preceding claim, characterized in that R_l R'i and/or R'V represent, independently of one another, a hydroxyl radical.

4. Process according to either one of Claims 2 and 3, characterized in that R₂ represents a group:

hydroxyl,

- (hydroxy)(Ci-C₄)alkoxy,

(di) (C i -C₄ ) (alkyl) amino ,

(di)hydroxy(C i -C₄)alkylamino,

C i -C₄)alkoxycarbonyl(C i -C₄)alkylamino,

or forms, with R₆ and the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, preferably saturated, heterocycle comprising 5 or 6 ring members:

• comprising one or more heteroatoms and/or groups chosen from -0-, -S-, -N(H)-, -N(R"₄)- with R"₄ as defined in Claim 1, -C(O)-, -C(S)- and/or

• optionally substituted with one or more radicals, which may be identical or different, chosen from i) hydroxyl, ii) (Ci-C₄ (hydroxy)alkyl, iii) Ci-

C₄ alkoxycarbonyl and iv) carboxy -COOH radicals;

more preferentially, R₂ represents a hydroxyl group, or a propylamino, hydroxyethylamino or methoxycarbonylmethylamino radical, or R₂ and R₆ form, with the carbon atoms to which they are attached, a saturated 5- or 6-membered heterocycle comprising one or two heteroatoms and/or groups chosen from O, S, - N(H)-, -N(R"₄) with R"₄ as defined in Claim 1, -C(O)-, -C(S)- such as O and/or C(O), even more preferentially form a tetrahydropyran group.

5. Process according to any one of Claims 2 to 4, characterized in that R₃ represents a hydrogen atom or forms, with R₂ and the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, preferably saturated, heterocycle comprising 5 or 6 ring members:

• comprising one or more heteroatoms and/or groups chosen from -O-, -S-, -N(H)-, -N(R"₄)- with R”₄ as defined in Claim 1, -S(O)-, -S(0)₂-, -C(O)-, -C(S)- and/or

• optionally substituted with one or more radicals, which may be identical or different, chosen from i) hydroxyl, ii) (Ci-C₄ (hydroxy)alkyl, iii) Ci- C₄ alkoxycarbonyl and iv) carboxy -COOH radicals; more preferentially, R₃ represents a hydrogen atom or R₂ and R₃ form, with the carbon atoms to which they are attached, a saturated 5- or 6-membered heterocycle comprising one or two heteroatoms and/or groups chosen from O, S, -N(H)-, -N(R"₄) with R"₄ as defined in Claim 1, -C(O)-, -C(S)- such as O and/or C(O), even more preferentially a tetrahydropyran group.

6. Process according to any one of Claims 2 to 5, characterized in that R’₂ represents a group:

- hydroxyl,

- ethoxy,

- hydroxyethyloxy,

or forms, with R>, and the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, preferably saturated, heterocycle comprising 5 or 6 ring members:

· comprising one or more heteroatoms and/or groups chosen from -0-, -S-,

-N(H)-, -N(R"₄)- with R”₄ as defined in Claim 1, -S(O)-, -S(0)₂-, -C(O)-, -C(S)- and/or

• optionally substituted with one or more radicals, which may be identical or different, chosen from i) hydroxyl, ii) (Ci-C₄ (hydroxy)alkyl, iii) Ci- C₄ alkoxycarbonyl and iv) carboxy -COOH radicals;

more preferentially, R’₂ represents a hydroxyl group, an ethoxy group or a hydroxyethyloxy group, or R’₂ and R’₆ form, with the carbon atoms to which they are attached, a saturated 5- or 6-membered heterocycle comprising one or two heteroatoms and/or groups chosen from O, S, -N(H)-, -N(R"₄) as defined in Claim 1, -C(O)-, -C(S)- such as O and/or C(O), even more preferentially form a tetrahydropyran-2-one group.

7. Process according to any one of Claims 2 to 6, characterized in that R’₃ represents a hydrogen atom or forms, with R’₂ and the carbon atoms to which they are attached, an aromatic or non-aromatic, saturated or unsaturated, preferably saturated, heterocycle comprising 5 or 6 ring members:

• comprising one or more heteroatoms and/or groups chosen from -O-, -S-, -N(H)-, -N(R"₄)- with R”₄ as defined in Claim 1, -S(O)-, -S(0)₂-, -C(O)-, -C(S)- and/or • optionally substituted with one or more radicals, which may be identical or different, chosen from i) hydroxyl, ii) (C₁-C₄ (hydroxy)alkyl, iii) Ci- C₄ alkoxycarbonyl and iv) carboxy -COOH radicals;

more preferentially, R’₃ represents a hydrogen atom or R’₂ and R’₃ form, with the carbon atoms to which they are attached, a saturated 5- or 6-membered heterocycle comprising one or two heteroatoms and/or groups chosen from O, S, -N(H)-, -N(R"₄) with R"₄ as defined in Claim 1, -C(O)-, -C(S)- such as O and/or C(O), even more preferentially form a tetrahydropyran-2-one group.

8. Process according to any one of Claims 2 to 7, characterized in that R₆ represents a hydrogen atom, or a group chosen from a) (hydroxy)(Ci-Cs)alkyl, b) carboxy(Ci-Cs)alkyl, c) (C i -CsjalkoxycarbonyUC i -Csjalkyl, d) hydroxy(Ci- C₄)alkylaminocarbonyl(C i -C₅ )alkyl, e) hydroxy(C ₁ -C₄)alkyloxycarbonyl(C ₁ -

Cs)alkyl, f) heterocycle-C(0)-(Ci-C₅)alkyl with heterocycle comprising 6 ring members, being saturated, comprising 1 or 2 heteroatoms chosen from O and N and being optionally substituted with one or more (Ci-C₄)alkyl groups, such as piperazino, piperidino or morpholino, preferably f) represents an N-(C ₁ - C₄)alkylpiperazinocarbonyl(C ₁ -C₅ )alkyl group;

-hydroxyethyloxycarbonylethyl,

-hydroxyethylaminocarbonylethyl,

-ethoxycarbonylethyl,

-N-methylpiperazinocarbonylethyl.

9. Process according to any one of Claims 2 to 8, characterized in that R’₆ represents a hydrogen atom or a (Ci-C₄)alkyl group such as methyl, preferably RY, represents a hydrogen atom.

10. Process according to any one of Claims 2 to 9, characterized in that:

- R"i represents a hydroxyl group,

- R"₂ represents a hydroxyl group,

- R” ₃ represents a hydrogen atom,

- R” ₆ represents a hydrogen atom, - p” is 0.

11. Process according to any one of Claims 2 to 10, characterized in that the oxidation coupler(s) of formula (IA), (I), (II) or (III) are chosen from the compounds (1) to (21), and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and the mixtures thereof:

12. Process according to the preceding claim, characterized in that the oxidation coupler(s) are in particular chosen from the compounds (1), (3), (4), (5), (6), (7), (8), (9), (13) and (17), even more preferentially from the compounds (1), (2), (3), (5), (6), (7), (8) and (9), and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and the mixtures thereof.

13. Process according to any one of the preceding claims, characterized in that one or more oxidation bases are applied to said keratin fibres during step(s) i).

14. Process according to any one of the preceding claims, comprising at least ii) a step of applying to said keratin fibres an oxidizing cosmetic composition comprising one or more chemical oxidizing agents, preferably chosen from hydrogen peroxide, urea peroxide, alkali metal bromates, persalts such as perborates and persulfates, peracids, and oxidase enzymes (with the possible cofactors thereof), in particular peroxidases, 2-electron oxidoreductases such as uricases, and 4-electron oxygenases, for instance laccases; more preferentially the chemical oxidizing agent is hydrogen peroxide;

15. Process according to the preceding claim, characterized in that steps i) and ii) are carried out sequentially.

16. Process according to any one of Claims 1 to 14, characterized in that the application to said fibres:

- of the oxidation coupler(s) as defined according to any one of Claims 1 to

12;

of the chemical oxidizing agent(s) as defined according to Claim 14; of the optional oxidation base(s);

is simultaneous.

17. Cosmetic composition comprising:

one or more oxidation couplers as defined according to any one of Claims 1 to 12, preferably the oxidation coupler(s) are chosen from the compounds (1) to (21) as defined in Claim 11; and

- one or more oxidation bases.

18. Composition according to the preceding claim, characterized in that it also comprises one or more chemical oxidizing agents, preferably chosen from hydrogen peroxide, urea peroxide, alkali metal bromates, persalts such as perborates and persulfates, peracids, and oxidase enzymes (with the possible cofactors thereof), in particular peroxidases, 2-electron oxidoreductases such as uricases, and 4-electron oxygenases, for instance laccases; more preferentially, the chemical oxidizing agent is hydrogen peroxide.

19. Composition according to the preceding claim, characterized in that the pH of the composition is between 7.5 and 12, preferably between 8 and 11, and even more preferentially between 9 and 10.

20. Compound chosen from the compounds (1), (2), (13) and (17) as defined in Claim 11, and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and the mixtures thereof.

21. Composition comprising at least one compound chosen from the compounds (1), (2), (13) and (17) as defined according to Claim 11, and also the organic or mineral acid or base salts thereof, the tautomeric forms thereof, the optical isomers thereof, the geometric isomers thereof, the solvates thereof such as the hydrates thereof; and the mixtures thereof.

22. Multicompartment device comprising a first compartment containing one or more oxidation couplers as defined in any one of Claims 1 to 12, and a second compartment comprising one or more chemical oxidizing agents as defined in Claim 14.