PROCESS FOR THE PREDICTABLE DYEING OF KERATINOUS FIBRES
BY APPLICATION OF A COMPOSITION COMPRISING A DIAMINO-
N,N-DIHYDROPYRAZOLONE DERIVATIVE AND OF A FUNDAMENTAL
OR GOLDEN-HIGHLIGHTS COMPOSITION
A subject-matter of the invention is a process for the predictable colouring of keratinous fibres and in particular of human keratinous fibres, such as the hair, by application to the said fibres of a composition comprising at least one oxidation base derived from diamino-N,N-dihydropyrazolone and at least one specific coupler, mixed with a "fundamental" and/or "golden fundamental" and/or "golden" composition.
It is known to dye keratinous fibres and in particular human keratinous fibres, such as the hair, with dyeing compositions comprising oxidation dye precursors, in particular ortho- or para-phenylenediamines, ortho- or para-aminophenols, or heterocyclic compounds, such as diaminopyrazole derivatives, pyrazolo[1,5-a]pyrimidine derivatives, pyrimidine derivatives, pyridine derivatives, indole derivatives or indoline derivatives, generally known as oxidation bases. Oxidation dye precursors or oxidation bases are colourless or weakly coloured compounds which, in combination with oxidizing products, can give rise, by an oxidative coupling process, to coloured or colouring compounds. Permanent colourings are thus obtained.
It is also known that it is possible to vary the shades obtained with these oxidation bases by combining them with couplers or colouring modifiers, the latter being chosen in particular from meta-phenylenediamines, meta-aminophenols, meta-hydroxyphenols and certain heterocyclic compounds.
The variety of the molecules involved as oxidation bases and couplers makes it possible to obtain a rich palette of colours.

The use of oxidation bases, such as para-phenylenediamine and para-aminophenol derivatives, makes it possible to obtain a fairly broad range of colours at basic pH without, however, achieving shades of good chromaticity, while conferring on the hair excellent properties of intensity of colour, a variety of shades, of uniformity in the colour and of resistance to external agents.
In conventional oxidation dyeing processes, the professional or nonprofessional user, wishing to obtain predictable colours, can mix compositions of different shades in order to access the desired colour, indeed even the desired intermediate shade. For example, it is expected that a "blond" dyeing composition mixed with a "coppery highlight" composition gives a "blond with coppery highlight" colouring to keratinous fibres. The advantage of these mixtures thus lies in the possibility of being able to predict the shaded colouring and thus of not limiting the creativity of the user.
In point of fact, certain oxidation dyeing precursors do not make it possible to achieve a predictable colouring as a mixture with another composition comprising "fundamental" and/or "golden fundamental" and/or "golden" shades. The result of the mixing of the dyeing compositions is risky or whimsical. In particular, it proved to be the case that the result of colour on the keratinous fibres was not very predictable, during mixings carried out by the styling practitioner between the "coppery highlight" or "light red" shades and "fundamental" and/or "golden fundamental" and/or "golden" compositions, when one of the compositions comprises in particular the coupler 6 -chloro-2 -methyl-5-aminophenol.
Consequently, the aim of the present invention is to

provide a novel process for the colouring of keratinous fibres which makes possible a predictable colouring with varied, powerful, chromatic, attractive and not very selective shades which is highly resistant to the various attacks which hair may be subjected to, such as shampoos, light, sweat and permanent deformations.
This technical problem has been solved by a process for colouring keratinous fibres which consists in applying, to the fibres, a mixture of a composition (A) and of a "fundamental" or "golden fundamental" or "golden" dyeing composition (B) ; the said composition (A) comprising at least one coupler 6-chloro-2-methyl-5-aminophenol and at least one oxidation base derived from diamino-N,N-dihydropyrazolone of formula (I) or one of its salts,
(Formula Removed)
in which:
• R1, R2, R3 and R4, which are identical or different,
represent:
a linear or branched C1-C6 alkyl radical optionally substituted by one or more radicals chosen from the group consisting of an OR5 radical, an NR6R7 radical, a carboxyl radical, a sulpho radical, a carboxamido CONR6R7 radical, a sulphonamido S02NR6R7 radical, a heteroaryl or an aryl optionally substituted by one or more (C1-C4) alkyl, hydroxyl, C1-C2 alkoxy, amino or (di) (C1-C2) alkylamino groups;
an aryl radical optionally substituted by one or more (C1-C4) alkyl, hydroxyl, C1-C2 alkoxy, amino or (di) (C1-C2)alkylamino groups;
- a 5- or 6-membered heteroaryl radical optionally substituted by one or more radicals chosen from (C1-C2) alkyl or (C1-C2) alkoxy;

• R3 and R4 can also represent a hydrogen atom;
• R5, R6 and R7, which are identical or different,
represent:
a hydrogen a torn;
a linear or branched C1-C4 alkyl radical optionally substituted by one or more radicals chosen from hydroxyl, (C1-C2) alkoxy, carboxamido CONR8R9, sulphonyl S02R8 or aryl optionally substituted by a (C1-C4) alkyl, hydroxyl, (C1-C2) alkoxy, amino or (di) (C1-C2) alkylamino; or an aryl radical optionally substituted by a (Ca-C4)alkyl, hydroxyl, (C1-C2) alkoxy, amino or (di) (C1-C2) alkylamino;
• R6 and R7, which are identical or different, can
also represent a carboxamido CONR8R9 radical or a
sulphonyl S02R8 radical;
• R8 and R9, which are identical or different,
represent a hydrogen atom or a linear or branched
C1-C4 alkyl radical optionally substituted by one
or more hydroxyl or (C1-C2) alkoxy groups;
• R1 and R2, on the one hand, and R3 and R4, on the
other hand, can form, with the nitrogen atom or
atoms to which they are attached, a saturated or
unsaturated 5- to 7-membered heterocycle
optionally substituted by one or more radicals
chosen from the group consisting of halogen atoms,
amino, (di) (C1-C4)alkylamino, hydroxyl, carboxyl,
carboxamido or (C1-C2) alkoxy radicals or (C1-C4) alkyl
radicals optionally substituted by one or more
hydroxyl, amino, (di)alkylamino, alkoxy, carboxyl
or sulphonyl radicals;
• R3 and R4 can also form, together with the nitrogen
atom to which they are attached, a 5- or 7-
membered heterocycle, the carbon atoms of which
can be replaced by an oxygen atom or an optionally
substituted nitrogen atom.
Unexpectedly, when the coupler of substituted meta-aminophenol type, such as 6-chloro-2-methyl-5-amino-

phenol, in the composition (A) is combined with at least one oxidation base of formula (I), such as 2,3-diamino-6,7-dihydro-lH,5H-pyrazolo[1,2-a]pyrazol-1-one, in the same composition (A) , this makes it possible to obtain colourings which are predictable with regard to the colour of the keratinous fibres, once mixed with a "fundamental" and/or "golden fundamental" and/or "golden" dyeing composition (B). The colouring obtained after the application of the mixture to the said fibres is that expected, i.e. the keratinous fibres are coloured with shades with "coppery" or "red" highlights.
Furthermore, this colouring is powerful, attractive, not very selective and resistant to the various attacks which hair may be subjected to, such as shampoos, light, sweat and permanent deformations. It also makes it possible to obtain intense and varied colourings at neutral pH. It makes it possible in particular to obtain natural shades.
In the context of the present invention, an alkyl radical corresponds to a saturated, linear or branched, preferably C1-C10 unless otherwise indicated, preferentially C1-C6, preferably C1-C4, hydrocarbon chain, such as the methyl, ethyl, propyl, isopropyl, isobutyl, tert-butyl, pentyl or hexyl radical.
In the context of the present invention, the heteroatom or heteroatoms can be chosen from an oxygen atom, a nitrogen atom, a sulphur atom or a phosphorus atom.
In the context of the present invention, a halogen atom can be chosen from a chlorine atom, a bromine atom, an iodine atom and a fluorine atom.
More particularly, in the formula (I) , the R1 and R2 radicals, which are identical or different, are chosen from:

- a C1-C6, preferably C1-C4, alkyl radical optionally
substituted by a hydroxyl, a (C1-C2) alkoxy, an
amino or a (di) (C1-C2) alkylamino;
- a phenyl, methoxyphenyl, ethoxyphenyl or benzyl
radical.
Preferably, the R1 and R2 radicals, which are identical
or different, are chosen from a methyl, ethyl,
2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl or
phenyl radical.
According to another embodiment, the R1 and R2 radicals form, together with the nitrogen atoms to which they are attached, an optionally substituted, saturated or unsaturated, 5- or 6-membered ring.
The R1 and R2 radicals form, together with the nitrogen atoms to which they are attached, a pyrazolidine or pyridazolidine ring optionally substituted by one or more (C1-C4) alkyl, hydroxyl, (C1-C2) alkoxy, carboxyl, carboxamido, amino or (di) (C1-C2) alkylamino radicals.
More advantageously still, the R1 and R2 radicals form, together with the nitrogen atoms to which they are attached, a pyrazolidine or pyridazolidine ring.
As regards the R3 and R4 radicals, the latter, which are identical or different, are chosen more particularly from a hydrogen atom; a linear or branched C1-C6, preferably (C1-C4) alkyl radical optionally substituted by one or more hydroxyl, (C1-C2) alkoxy, amino or (di)(C1-C2)alkylamino radicals; or a phenyl radical optionally substituted by one or more hydroxyl, amino or ((C1-C2)alkoxy radicals.
Preferably, the R3 and R4 radicals, which are identical or different, are chosen from a hydrogen atom or a methyl, ethyl, isopropyl, 2-hydroxyethyl, 3-hydroxy-

propyl, 2-hydroxypropyl or 2-carboxyethyl radical. According to a specific embodiment, the R3 and R4 radicals represent a hydrogen atom.
According to another embodiment, the R3 and R4 radicals form, together with the nitrogen atom to which they are attached, a 5- or 7-membered ring chosen from the heterocycles pyrrolidine, piperidine, homopiperidine, piperazine or homopiperazine; it being possible for the said rings to be substituted by one or more hydroxyl, amino, (di) (C1-C2)alkylamino, carboxyl, carboxamido or C1-C4 alkyl radicals, the C1-C4 alkyl radical optionally being substituted by one or more hydroxyl, amino or (di) (C1-C2) alkylamino radicals.
More particularly, the R3 and R4 radicals form, together with the nitrogen atom to which they are attached, a 5-or 7-membered ring chosen from pyrrolidine, 2,5-dimethylpyrrolidine, pyrrolidine-2-carboxylic acid, 3-hydroxypyrrolidine-2-carboxylic acid, 4-hydroxypyrrol-idine-2-carboxylic acid, 2,4-dicarboxypyrrolidine, 3-hydroxy-2-hydroxymethylpyrrolidine, 2-carboxamido-pyrrolidine, 3-hydroxy-2-carboxamidopyrrolidine, 2-(di-ethylcarboxamido)pyrrolidine, 2-(hydroxymethyl)pyrrol-idine, 3,4-dihydroxy-2-(hydroxymethyl)pyrrolidine, 3-hydroxypyrrolidine, 3,4-dihydroxypyrrolidine, 3-aminopyrrolidine, 3-(methylamino)pyrrolidine, 3-(di-methylamino)pyrrolidine, 4-amino-3-hydroxypyrrolidine, 3-hydroxy-4-[(2-hydroxyethyl)amino]pyrrolidine, piper-idine, 2,6-dimethylpiperidine, 2-carboxypiperidine, 2-carboxamidopiperidine, 2-hydroxymethylpiperidine, 3-hydroxy-2-hydroxymethylpiperidine, 3-hydroxypiper-idine, 4-hydroxypiperidine, 3-hydroxymethylpiperidine, homopiperidine, 2-carboxyhomopiperidine, 2-carboxamido-homopiperidine, homopiperazine, N-methylhomopiperazine or N-(2-hydroxyethyl)homopiperazine.
Preferably, the R3 and R4 radicals form, together with the nitrogen atom to which they are attached, a 5- or

7-membered ring chosen from pyrrolidine, 3-hydroxy-
pyrrolidine, 3-aminopyrrolidine, 3-(dimethylamino)-
pyrrolidine, pyrrolidine-2-carboxylic acid, 3-
hydroxypyrrolidine-2-carboxylic acid, piperidine,
hydroxypiperidine, homopiperidine, diazepane, N-
methylhomopiperazine or N- (β-
hydroxyethyl)homopiperazine.
In accordance with an even more preferred embodiment of the invention, the R3 and R4 radicals form, together with the nitrogen atom to which they are attached, a 5-membered ring, such as pyrrolidine, 3-hydroxypyrrol-idine, 3-aminopyrrolidine or 3-(dimethylamino)pyrrol-idine .
The compounds of formula (I) can optionally be salified by strong inorganic acids, such as, for example, HCl, HBr, HI, H2SO4 or H3PO4, or organic acids, such as, for example, acetic acid, lactic acid, tartaric acid, citric acid, succinic acid, benzenesulphonic acid, para-toluenesulphonic acid, formic acid or (C1-C4 alkyl)SO3H acid, such as methanesulphonic acid.
They can also be in the form of solvates, for example a hydrate or a solvate of a linear or branched alkyl, such as ethanol or isopropanol.
Mention may be made, as examples of derivatives of formula (I), of the compounds presented below or their addition salts:
4,5-diamino-l,2-dimethyl-l,2-dihydropyrazol-3-one;
4-amino-5-methylamino-1,2-dimethyl-1,2-dihydropyrazol-
3 -one;
4-amino-5-dimethylamino-1, 2-dimethyl-l,2-
dihydropyrazol-3-one;
4-amino-5-(2-hydroxyethyl)amino-1,2-dimethyl-l,2-
dihydropyrazol-3-one;

4-amino-5-(pyrrolidin-1-yl)-1,2-dimethyl-1,2-dihydropyrazol-3-one;
4-amino-5-(piperidin-1-yl)-1,2-dimethyl-1,2-dihydropyrazol-3-one;
4,5-diamino-l,2-di(2-hydroxyethyl)-1,2-dihydropyrazol-
3-one;
4-amino-5-methylamino-l,2-di(2-hydroxyethyl)-1,2-
dihydropyrazol-3-one;
4-amino-5-dimethylamino-l,2-di(2-hydroxyethyl)-1,2-
dihydropyrazol-3-one;
4-amino-5-(2-hydroxyethyl)amino-1,2-di(2-hydroxyethyl)-
1,2-dihydropyrazol-3-one;
4-amino-5-(pyrrolidin-1-yl)-1,2-di(2-hydroxyethyl)-1,2-
dihydropyrazol-3-one;
4-amino-5-(piperidin-1-yl)-1,2-di(2-hydroxyethyl)-1,2-
dihydropyrazol-3-one;
4,5-diamino-l,2-diethyl-l,2-dihydropyrazol-3-one;
4,5-diamino-l,2-phenyl-l,2-dihydropyrazol-3-one;
4,5-diamino-l-ethyl-2-methyl-1,2-dihydropyrazol-3-one;
4,5-diamino-2-ethyl-l-methyl-l,2-dihydropyrazol-3-one;
4,5-diamino-l-phenyl-2-methyl-l,2-dihydropyrazol-3-one;
4,5-diamino-2-phenyl-l-methyl-l,2-dihydropyrazol-3-one;
4,5-diamino-l-(2-hydroxyethyl)-2-methyl-1,2-
dihydropyrazol-3-one;
4,5-diamino-2-(2-hydroxyethyl)-1-methyl-l,2-
dihydropyrazol-3-one;
2,3-diamino-6,7-dihydro-lH,5H-pyrazolo[1,2-a]pyrazol-1-
one,-
2-amino-3-methylamino-6,7-dihydro-lH,5H-pyrazolo[1,2-
a]pyrazol-1-one;
2-amino-3-dimethylamino-6,7-dihydro-lH,5H-pyrazolo[1,2-
a]pyrazol-1-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[1,2-a]pyrazol-1-one;

2-amino-3-(2-hydroxyethyl)amino-6,7-dihydro-lH,5H-
pyrazolo[1,2-a]pyrazol-1-one;
2-amino-3-(2-hydroxypropyl)amino-6,7-dihydro-lH,5H-
pyrazolo[1,2-a]pyrazol-1-one;
2-amino-3-bis[(2-hydroxyethyl)amino]-6,7-dihydro-lH,5H-
pyrazolo[1,2-a]pyrazol-1-one;
2-amino-3-(pyrrolidin-1-yl)-6,7-dihydro-lH,5H-
pyrazolo[1,2-a]pyrazol-1-one;
2-amino-3-(3-hydroxypyrrolidin-l-yl)-6,7-dihydro-lH,5H-
pyrazolo[1,2-a]pyrazol-1-one;
2-amino-3-(piperidin-1-yl)-6,7-dihydro-lH,5H-
pyrazolo[1,2-a]pyrazol-1-one;
2,3-diamino-6-hydroxy-6,7-dihydro-lH,5H-pyrazolo[1,2-
a]pyrazol-1-one;
2,3-diamino-6-methyl-6,7-dihydro-lH,5H-pyrazolo[1,2-
a]pyrazol-1-one;
2,3-diamino-6,6-dimethyl-6,7-dihydro-lH,5H-
pyrazolo[1,2-a]pyrazol-1-one;
2,3-diamino-5,6,7,8-tetrahydro-lH,6H-pyridazino[1,2-a]pyrazol-1-one;
2,3-diamino-5,8-dihydro-lH,6H-pyridazino[1,2-a]pyrazol-1-one;
4-amino-5-dimethylamino-l,2-diethyl-l,2-dihydropyrazol-
3-one;
4-amino-l,2-diethyl-5-ethylamino-l,2-dihydropyrazol-3-
one;
4-amino-l,2-diethyl-5-isopropylamino-l,2-dihydropyrazol-
3-one;
4-amino-l,2-diethyl-5-(2-hydroxyethylamino)-1,2-
dihydropyrazol-3-one;
4-amino-5-(2-dimethylaminoethylamino)-1,2-diethyl-l,2-
dihydropyrazol-3-one;
4-amino-5-[bis(2-hydroxyethyl)amino]-1,2-diethyl-l,2-
dihydropyrazol-3-one ;
4-amino-l,2-diethyl-5-(3-(imidazol-1-yl)propylamino)-

1,2-dihydropyrazol-3-one;
4-amino-5-dimethylamino-l,2-diethyl-l,2-dihydropyrazol-3-one;
4-amino-l,2-diethyl-5-ethylamino-l,2-dihydropyrazol-3-one;
4-amino-l,2-diethyl-5-isopropylamino-l,2-dihydropyrazol-3-one;
4-amino-l,2-diethyl-5-(2-hydroxyethylamino)-1,2-dihydropyrazol-3-one;
4-amino-5-(2-dimethylaminoethylamino)-1,2-diethyl-l,2-dihydropyrazol-3 -one;
4-amino-5-[bis(2-hydroxyethyl)amino]-1,2-diethyl-l,2-dihydropyrazol-3-one;
4-amino-l,2-diethyl-5-(3-(imidazol-l-yl)propylamino)-1,2-dihydropyrazol-3-one;
4-amino-l,2-diethyl-5-(3-hydroxypyrrolidin-l-yl)-1,2-dihydropyrazol-3-one;
4-amino-l,2-diethyl-5-(pyrrolidin-1-yl)-1,2-dihydropyrazol-3-one;
4-amino-5-(3-dimethylaminopyrrolidin-l-yl)-1,2-diethyl-1,2-dihydropyrazol-3-one;
4-amino-l,2-diethyl-5-(4-methylpiperazin-l-yl)-pyrazolidin-3-one;
2,3-diamino-6-hydroxy-6,7-dihydro-5H-pyrazolo[1,2-a]pyrazol-1-one;
some of which are represented below in order to illustrate the names by the chemical structures:

(Table Removed)
Among these compounds, the diamino-N, N-dihydro-pyrazolone derivatives of formula (I) or their addition salts which are particularly preferred are: 2,3-diamino-6,7-dihydro-lH,5H-pyrazolo[1,2-a]pyrazol-1-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[1,2-a]pyrazol-1-one;
2-amino-3-(pyrrolidin-1-yl)-6,7-dihydro-lH,5H-pyrazolo[1,2-a]pyrazol-1-one;
4,5-diamino-l,2-dimethyl-l,2-dihydropyrazol-3-one; 4 , 5 -diamino -1,2- diethyl -1, 2 -dihydropyrazol - 3 - one ,-4,5-diamino-l,2-di(2-hydroxyethyl)-1,2-dihydropyrazol-3-one;
2-amino-3-(2-hydroxyethyl)amino-6,7-dihydro-lH,5H-pyrazolo[1,2-a]pyrazol-1-one;
2-amino-3-dimethylamino-6,7-dihydro-lH,5H-pyrazolo[1,2-a]pyrazol-1-one;
2,3-diamino-5,6,7,8-tetrahydro-lH,6H-pyridazino [1,2-a]pyrazol-1-one;
4-amino-1,2-diethyl- 5-(pyrrolidin-1-yl)-1,2-dihydro-pyrazol -3-one;
4-amino-5-(3-dimethylaminopyrrolidin-l-yl)-1,2-diethyl-1,2-dihydropyrazol-3-one;
2,3-diamino-6-hydroxy-6,7-dihydro-lH,5H-pyrazolo [1,2-a]pyrazol-1-one.
Preference will be given even more particularly to the
use, as compound of formula (I), of 2,3-diamino-6,7-dihydro-lH,5H-pyrazolo[1,2-a]pyrazol-1-one and its addition salts.
The composition (A) comprises at least one coupler of specific halogenated substituted meta-aminophenol type chosen from 6-chloro-2-methyl-5-aminophenol and one of its salts.
Preferably, the amount of 6-chloro-2-methyl-5-aminophenol is between 0.001 and 8% and more preferably between 0.1 and 5% of the total weight of the dyeing composition (A).
The oxidation base or bases of formula (I) are generally each present in an amount of between 0.001 and 8% by weight approximately of the total weight of the dyeing composition (A), preferably between 0.1 and 5%.
A subject-matter of a specific embodiment is a composition (A) of coppery shade, in which the molar ratio of the oxidation base of formula (I), including in particular 2,3-diamino-6,7-dihydro-lH,5H-pyrazolo[1,2-a]pyrazol-1-one, to the coupler 6-chloro-2-methyl-5-aminophenol is less than 1. Preferably, the said ratio is between 0.5 and 0.95.
In another embodiment, the composition (A) of coppery shade comprises another preferably nonhalogenated substituted meta-aminophenol coupler, particularly 2-methyl-5-aminophenol, for which the molar ratio of the oxidation base of formula (I), in particular 2,3-diamino-6,7-dihydro-lH,5H-pyrazolo[1,2-a]pyrazol-1-one, to the additional coupler is greater than 1. Preferably, the said ratio is between 2 and 5.
The composition (A) of use in the process of the invention can comprise other oxidation bases and other

couplers different from those of use in the present invention and conventionally used for the dyeing of keratinous fibres.
The composition (A) of the present invention can, for example, comprise additional oxidation bases chosen from para-phenylenediamines, bisphenylalkylenediamines, para-aminophenols, bis-para-aminophenols, ortho-amino-phenols, ortho-phenylenediamines, heterocyclic bases other than the derivatives of formula (I) as defined above and their addition salts.
Mention may be made, among para-phenylenediamines, by
way of example, of para-phenylenediamine, para-
toluylenediamine, 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(β-hydroxyethyl)-
para-phenylenediamine, 4-N, N-bis(β-hydroxyethyl)amino-
2-methylaniline, 4-N,N-bis(β-hydroxyethyl)amino-
2-chloroaniline, 2-(β-hydroxyethyl)-para-phenylene-
diamine, 2-fluoro-para-phenylenediamine, 2-isopropyl-
para-phenylenediamine, N-(β-hydroxypropyl)-para-
phenylenediamine , 2-hydroxymethyl-para-
phenylenediamine, N,N-dimethyl-3-methyl-para-phenylene-
diamine, N,N-(ethyl, β-hydroxyethyl)-para-phenylene-
diamine, N- (β,y-dihydroxypropyl)-para-phenylenediamine,
N-(4' -aminophenyl)-para-phenylenediamine, N-phenyl-
para-phenylenediamine, 2-(β-hydroxyethyloxy)-para-
phenylenediamine, 2-(β-acetylaminoethyloxy)-para-
phenylenediamine, N-(β-methoxyethyl)-para-phenylene-
diamine, 4-aminophenylpyrrolidine, 2-thienyl-para-
phenylenediamine, 2-(β-hydroxyethylamino)-5-amino-
toluene, 3-hydroxy-l-(4'-aminophenyl)pyrrolidine and
their addition salts with an acid.

Among the para-phenylenediamines mentioned above, para-
phenylenediamine, para-toluylenediamine, 2-isopropyl-
para-phenylenediamine, 2- (β-hydroxyethyl)-para-
phenylenediamine, 2-(β-hydroxyethyloxy)-para-
phenylenediamine, 2,6-dimethyl-para-phenylenediamine,
2,6-diethyl-para-phenylenediamine, 2,3-dimethyl-para-
phenylenediamine, N,N-bis(β-hydroxyethyl)-para-
phenylenediamine, 2-chloro-para-phenylenediamine,
2- (β-acetylaminoethyloxy)-para-phenylenediamine and
their addition salts with an acid are particularly
preferred.
Mention may be made, among bisphenylalkylenediamines,
by way of example, of N,N'-bis(β-hydroxyethyl)-N,N'-
bis(4'-aminophenyl)-1,3-diaminopropanol, N,N'-bis(β-
hydroxyethyl)-N,N'-bis(4'-aminophenyl)ethylenediamine,
N,N'-bis(4-aminophenyl)tetramethylenediamine, N,N' -
bis(β-hydroxyethyl)-N,N'-bis(4-amino-
phenyl)tetramethylenediamine, N,N'-bis(4-methylamino-
phenyl)tetramethylenediamine, N,N'-bis(ethyl)-N,N'-
bis(4'-amino-3'-methylphenyl)ethylenediamine,
1,8-bis(2,5-diaminophenoxy)-3,6-dioxaoctane and their
addition salts with an acid.
Mention may be made, among para-aminophenols, by way of
example, of para-aminophenol, 4-amino-3-methylphenol,
4 -amino-3-fluorophenol, 4-amino-3-(hydroxymethyl)-
phenol, 4-amino-2-methylphenol, 4-amino-
2-(hydroxymethyl)phenol, 4-amino-2-(methoxy-
methyl)phenol, 4-amino-2-(aminomethyl)phenol, 4-amino-2-((P-hydroxyethyl)aminomethyl)phenol, 4-amino-2-fluorophenol and their addition salts with an acid.
Mention may be made, among ortho-aminophenols, by way of example, of 2-aminophenol, 2-amino-5-methylphenol, 2-amino-6-methylphenol, 5-acetamido-2-aminophenol and their addition salts with an acid.
Mention may be made, among heterocyclic bases, by way
of example, of pyridine derivatives, pyrimidine derivatives and pyrazole derivatives.
Mention may be made, among pyridine derivatives, of the compounds disclosed, for example, in Patents GB 1 026 978 and GB 1 153 196, such as 2,5-diaminopyridine, 2-[(4-methoxyphenyl)amino]-3-aminopyridine, 2,3-diamino-6-methoxypyridine, 2-[(β-methoxyethyl)amino]-3-amino-6-methoxypyridine, 3,4-diaminopyridine and their addition salts with an acid.
Other pyridine oxidation bases are the 3-aminopyrazolo[1,5-a]pyridine oxidation bases or their addition salts disclosed, for example, in Patent Application FR 2 801 308. Mention may be made, by way of example, of pyrazolo [1,5-a]pyridin-3-ylamine; 2-(acetylamino)pyrazolo[1,5-a]pyridin-3-ylamine; 2-(morpholin-4-yl)pyrazolo[1,5-a]pyridin-3-ylamine; 3-aminopyrazolo[1,5-a]pyridine-2-carboxylic acid; 2-methoxypyrazolo[1,5-a]pyridin-3-ylamine; (3-aminopyrazolo[1,5-a]pyridin-7-yl)methanol; 2-(3-aminopyrazolo[1,5-a]pyridin-5-yl)ethanol; 2- (3-aminopyrazolo [1, 5-a] pyridin-7-yl) ethanol ,-(3-aminopyrazolo[1,5-a]pyridin-2-yl)methanol; 3,6-diaminopyrazolo[1,5-a]pyridine;
3,4-diaminopyrazolo[1,5-a]pyridine; pyrazolo [1,5-a]-
pyridine-3,7-diamine; 7-(morpholin-4-yl)pyrazolo-
[1,5-a]pyridin-3-ylamine; pyrazolo[1,5-a]pyridine-
3,5-diamine; 5-(morpholin-4-yl)pyrazolo[1,5-a]pyridin-
3-ylamine; 2-[(3-aminopyrazolo[1,5-a]pyridin-
5-yl) (2-hydroxyethyl)amino]ethanol; 2-[(3-amino-pyrazolo [1,5-a]pyridin-7-yl)(2-hydroxyethyl)amino]-ethanol; 3-aminopyrazolo[1,5-a] pyridin-5-ol; 3-amino-pyrazolo [1,5-a]pyridin-4-ol; 3-aminopyrazolo[1,5-a] -pyridin-6-ol; 3-aminopyrazolo[1,5-a]pyridin-7-ol; and their addition salts with an acid or with a base.
Mention may be made, among pyrimidine derivatives, of the compounds disclosed, for example, in Patents DE 23 59 399; JP 88-169571; JP 05-63124; EP 0 770 375 or Patent Application WO 96/15765, such as 2,4,5,6-tetraaminopyrimidine, 4-hydroxy-2,5,6-triamino-pyrimidine, 2-hydroxy-4,5,6-triaminopyrimidine, 2,4-dihydroxy-5,6-diaminopyrimidine or 2,5,6-triamino-pyrimidine, and pyrazolopyrimidine derivatives, such as those mentioned in Patent Application FR-A-2 750 048 and among which may be mentioned pyrazolo[1, 5-a] -pyrimidine-3 , 7-diamine,- 2, 5-dimethylpyrazolo [1, 5-a] -pyrimidine-3,7-diamine; pyrazolo[1,5-a]pyrimidine-3,5-diamine; 2,7-dimethylpyrazolo[1,5-a]pyrimidine-3,5-diamine; 3-aminopyrazolo[1,5-a]pyrimidin-7-ol; 3-aminopyrazolo[1,5-a]pyrimidin-5-ol; 2-(3-amino-pyrazolo [1, 5-a]pyrimidin-7-ylamino)ethanol, 2-(7-amino-pyrazolo[1,5-a]pyrimidin-3-ylamino)ethanol, 2-[(3-aminopyrazolo[1,5-a]pyrimidin-7-yl)(2-hydroxy-ethyl) amino]ethanol, 2-[(7-aminopyrazolo [1,5-a]-pyrimidin-3-yl)(2-hydroxyethyl)amino]ethanol, 5,6-dimethylpyrazolo[1,5-a]pyrimidine-3,7-diamine, 2,6-dimethylpyrazolo[1,5-a]pyrimidine-3,7-diamine, 2,5,N7,N7-tetramethylpyrazolo[1,5-a]pyrimidine-3,7-diamine, 3-amino-5-methyl-7-(imidazolylpropyl-amino)pyrazolo[1,5-a]pyrimidine and their addition salts with an acid and their tautomeric forms, when a tautomeric equilibrium exists.
Mention may be made, among pyrazole derivatives, of the
compounds disclosed in Patents DE 38 43 892 and
DE 41 33 957 and Patent Applications WO 94/08969, WO
94/08970, FR-A-2 733 749 and DE 195 43 988, such as
4 , 5-diamino-l-methylpyrazole, 4,5-diamino-l-
((3-hydroxyethyl) pyrazole, 3 , 4 -diaminopyrazole,
4,5-diamino-l-(4'-chlorobenzyl)pyrazole, 4,5-diamino-
1,3-dimethylpyrazole, 4, 5-diamino-3-methyl-
1-phenylpyrazole, 4 , 5-diamino-l-methyl-3-phenyl-pyrazole, 4 -amino-1,3-dimethyl-5-hydrazinopyrazole, 1-benzyl-4,5-diamino-3-methylpyrazole, 4,5-diamino-

3-(tert-butyl)-1-methylpyrazole, 4,5-diamino-l-(tert-butyl)-3-methylpyrazole, 4,5-diamino-l-(P-hydroxy-ethyl) -3-methylpyrazole, 4,5-diamino-l-ethyl-3-methyl-pyrazole, 4,5-diamino-l-ethyl-3-(4'-methoxyphenyl)-pyrazole, 4 , 5-diamino-l-ethyl-3-(hydroxymethyl)-pyrazole, 4,5-diamino-3-hydroxymethyl-l-methylpyrazole, 4,5-diamino-3-hydroxymethyl-l-isopropylpyrazole, 4,5-diamino-3-methyl-l-isopropylpyrazole, 4-amino-5-(2'-aminoethyl)amino-1,3-dimethylpyrazole, 3,4,5-tri-aminopyrazole, 1-methyl-3 , 4, 5-triaminopyrazole, 3,5-diamino-l-methyl-4-(methylamino)pyrazole, 3,5-diamino-4-(β-hydroxyethyl)amino-1-methylpyrazole and their addition salts with an acid.
The additional oxidation base or bases present in the composition (A) of the invention are generally each present in an amount of between 0.001 and 10% by weight approximately of the total weight of the dyeing composition, preferably between 0.005 and 6%.
The dyeing composition (A) can also comprise additional couplers other than 6-chloro-2-methyl-5-aminophenol.
Mention may in particular be made of meta-phenylenediamines, meta-aminophenols, meta-diphenols, naphthalene couplers, heterocyclic couplers and their addition salts.
Mention may more particularly be made, among meta-
aminophenols of use in the context of the invention, of
3-aminophenol, 5-amino-2-methoxyphenol, 5-amino-
2- (p-hydroxyethyloxy)phenol, 5-amino-2-methylphenol,
5-N- (P-hydroxyethyl)amino-2-methylphenol, 5-N-
(β-hydroxyethyl)amino-4-methoxy-2-methylphenol, 5-amino-4-methoxy-2-methylphenol, 5-amino-4-chloro-2-methyl-phenol, 5-amino-2,4-dimethoxyphenol, 5- (y-hydroxypropyl-amino)-2-methylphenol, 3-(dimethylamino)phenol; 2-methyl-5-(dimethylamino)phenol, 2-ethyl-5-(dimethyl-amino) phenol, 2-methoxy-5-(dimethylamino)phenol, 2-eth-

oxy-5-(dimethylamino)phenol, 2-(β-hydroxyethyl)-5-
(dimethylamino)phenol, 3-(diethylamino)phenol, 2-methyl-
5-(diethylamino)phenol, 2-ethyl-5-(diethylamino)phenol, 2-methoxy-5-(diethylamino)phenol, 2-ethoxy-5-(diethyl-amino) phenol, 2- (β-hydroxyethyl)-5-(diethylamino)phenol, 3-[di(β-hydroxyethyl)amino] phenol, 2-methyl-5-[di(β-hydroxyethyl)amino]phenol, 2-ethyl-5-[di(β-hydroxy-ethyl) amino] phenol, 2-methoxy-5-[di(β-hydroxyethyl)-amino]phenol, 2-ethoxy-5-[di(β-hydroxyethyl)amino]-phenol, 2- (β-hydroxyethyl)-5-[di(β-hydroxyethyl)amino]-phenol, 3-(pyrrolidin-1-yl)phenol, 2-methyl-5-
(pyrrolidin-1-yl)phenol, 2-ethyl-5-(pyrrolidin-1-yl)-phenol, 2-methoxy-5-(pyrrolidin-1-yl)phenol, 2-ethoxy-5-
(pyrrolidin-l-yl)phenol, 2- (β-hydroxyethyl)-5-(pyrrol-idin-1-yl)phenol, 3-(piperidin-l-yl)phenol, 2-methyl-5-
(piperidin-1-yl)phenol, 2-ethyl-5-(piperidin-1-yl)-phenol, 2-methoxy-5-(piperidin-1-yl)phenol, 2-ethoxy-5-
(piperidin-1-yl)phenol, 2-(β-hydroxyethyl)-5-(piperidin-l-yl)phenol, 3-(piperazin-1-yl)phenol, 2-methyl-5-
(piperazin-l-yl)phenol, 2-ethyl-5-(piperazin-1-yl)-phenol, 2-methoxy-5-(piperazin-l-yl)phenol, 2-ethoxy-5-
(piperazin-1-yl)phenol, 2- (β-hydroxyethyl)-5-(piperazin-l-yl)phenol, 3-(4-methylpiperazin-l-yl)phenol, 2-methyl-5-(4-methylpiperazin-1-yl)phenol, 2-ethyl-5-(4-methyl-piperazin-l-yl) phenol, 2-methoxy-5-(4-methylpiperazin-l-yl)phenol, 2-ethoxy-5- (4-methylpiperazin-l-yl)phenol, 2-
(β-hydroxyethyl)-5-(4-methylpiperazin-1-yl)phenol, 3- (4-
ethylpiperazin-1-yl)phenol, 2-methyl-5-(4-ethyl-
piperazin-1-yl)phenol, 2-ethyl-5-(4-ethylpiperazin-l-
yDphenol, 2-methoxy-5- (4-ethylpiperazin-l-yl)phenol, 2-
ethoxy-5-(4-ethylpiperazin-l-yl)phenol, 2- (β-hydroxy-
ethyl) -5-(4-ethylpiperazin-l-yl)phenol, 3- (4-(β-hydroxy-
ethyl) piperazin-1-yl) phenol, 2-methyl-5-(4-(β-
hydroxyethyl)piperazin-1-yl)phenol, 2-ethyl-5-(4-(β-
hydroxyethyl)piperazin-1-yl)phenol, 2-methoxy-5-(4-(β-
hydroxyethyl)piperazin-l-yl)phenol, 2-ethoxy-5-(4-(β-
hydroxyethyl)piperazin-1-yl)phenol, 2- (P-hydroxyethyl)-
5-(4-(β-hydroxyethyl)piperazin-1-yl)phenol, 3-(mor-
pholin-4-yl)phenol, 2-methyl-5-(morpholin-4-yl)phenol,

2-ethyl-5-(morpholin-4-yl)phenol, 2-methoxy-5-(mor-pholin-4-yl)phenol, 2-ethoxy-5-(morpholin-4-yl)phenol, 2-(β-hydroxyethyl)-5-(morpholin-4-yl)phenol, and their addition salts.
Mention may be made, as examples of couplers other than meta-aminophenols, of 1,3-dihydroxybenzene, 1,3-dihydroxy-2-methylbenzene, 4-chloro-l,3-dihydroxy-benzene, 2,4-diamino-l-(β-hydroxyethyloxy)benzene, 2-amino-4-((β-hydroxyethylamino)-1-methoxybenzene, 1,3-diaminobenzene, 1,3-bis(2,4-diaminophenoxy)propane, 3-ureidoaniline, 3-ureido-l-(dimethylamino)benzene, sesamol, l-β-hydroxyethylamino-3 , 4-methylenedioxy-benzene, α-naphthol, 2-methyl-1-naphthol, 6-hydroxy-indole, 4-hydroxyindole, 4-hydroxy-N-methylindole, 2-amino-3-hydroxypyridine, 6-hydroxybenzomorpholine, 3 , 5-diamino-2, 6-dimethoxypyridine, 1-N- (β-hydroxy-ethyl) amino-3 , 4-methylenedioxybenzene, 2 , 6-bis (β-hydroxyethylamino)toluene and their addition salts with an acid.
Generally, the addition salts of the oxidation bases and couplers which can be used in the context of the invention are chosen in particular from the addition salts with an acid, such as hydrochlorides, hydrobromides, sulphates, citrates, succinates, tartrates, lactates, tosylates, benzenesulphonates, alkyltosylates, phosphates and acetates, and the addition salts with a base, such as sodium hydroxide, potassium hydroxide, aqueous ammonia, amines or alkanolamines.
The dyeing composition (A) in accordance with the invention can additionally comprise one or more direct dyes which can in particular be chosen from nitrobenzene dyes, azo direct dyes or methine direct dyes. These direct dyes can be nonionic, anionic or cationic in nature.

The term "fundamental" or "golden fundamental" or "golden" dyeing composition is understood to mean any composition comprising at least one oxidation base and optionally at least one coupler resulting, on keratinous fibres, in a "fundamental" or "golden fundamental" or "golden" shade, i.e. a shade which can, for example, be defined by the following general formula:
(Formula Removed)
in which:
H represents the level of tone of the shade
as defined in the work The Science of Hair
Care, 2nd edition, published by Taylor and
Francis Group, 2005, pp. 295, and H can,
according to the work, be between 1 and 10
inclusive; it is, according to the invention,
between 4 and 9; preferably, H is between 6
and 9 and more preferably between 7 and 9;
RI represents the primary or dominant
highlight with R1=l corresponding to the ash
highlight, Ri=2: iridescent highlight, R1=3:
golden highlight, R1=4: coppery highlight,
R1=5: mahogany highlight, R1=6: red highlight,
R1=7: green highlight; R1 according to the
invention is equal to 3;
R2 represents the secondary or correcting
highlight;
n represents an integer 0 or 1; when n
represents 1, the sign 0 softens the strength
of the RI (and R2) highlight;
N1 represents an integer 0 or 1;
n2 represents an integer 0 or 1; when n2
represents 1, R2 can take each of the values
from 1 to 7 mentioned above.
Mention may be made, as examples of fundamental or golden fundamental or golden shades according to the

invention, of the shades 7-8-9-7.03-8.03-9.03-7.3-8.3-9.3 .
Preferably, n1 has a value 1. More preferably, n1 has the value 1 and n is zero.
More particularly, the "fundamental" or "golden fundamental" or "golden" composition is chosen so that, in the presence of an oxidizing agent, it results, at ambient temperature on a lock of unpermed grey hair comprising 90% of white hairs, in the following values in the L*a*b* colorimetric system:
a* belongs to the range [0; +20] , b* belongs to the range [0; +20] and L* belongs to the range [0; +50].
A specific embodiment of the invention relates to the "fundamental" composition (B) having the following L*a*b* values:
a* belongs to the range [0; +6], b* belongs to the range [ + 10; +15] and L* belongs to the range [ + 20; + 50] .
Another embodiment of the invention relates to the "golden fundamental" composition (B) having the following L*a*b* values:
a* belongs to the range [ + 6; +10], b* belongs to the range [ + 15; +20] and L* belongs to the range [+20; +50] .
The oxidation base or bases present in the composition (B) and the coupler or couplers optionally present in the composition (B) are as defined above for additional bases and couplers of the composition (A).
Preferably, the composition (B) does not comprise compounds of formula (I) or 6-chloro-2-methyl-5-aminophenol.
In a specific embodiment of the invention, the

composition (B) comprises at least one oxidation base chosen from para-phenylenediamines, of which in particular para-phenylenediamine, para-toluylene-diamine, 2-isopropyl-para-phenylenediamine, 2- (β-hydroxyethyl) -para-phenylenediamine, 2- (β-hydroxy-ethyloxy)-para-phenylenediamine, 2,6-dimethyl-para-phenylenediamine, 2,6-diethyl-para-phenylenediamine, 2, 3-dimethyl-para-phenylenediamine, N,N-bis(β-hydroxy-ethyl)-para-phenylenediamine, 2-chloro-para-phenylene-diamine, 2-(β-acetylaminoethyloxy)-para-phenylene-diamine and their addition salts with an acid are particularly preferred. Preferably, the oxidation base of the composition (B) is chosen from para-toluene-diamine, para-phenylenediamine and one of their salts.
Furthermore, in an advantageous embodiment, the proportion by weight of the oxidation base or bases of the composition (B) is preferably less than or equal to 5 mmol per 100 g of the said composition.
Another embodiment of the invention relates to the coupler or couplers of the composition (B) chosen from meta-diphenols, such as 1,3-dihydroxybenzene, meta-aminophenols, such as 3-aminophenol, and meta-phenylenediamines, such as 2,4-diamino-l-(β-hydroxy-ethyloxy)benzene.
The medium appropriate for dyeing, also referred to as dyeing vehicle, is a cosmetic medium generally composed of water or of a mixture of water and of at least one organic solvent in order to dissolve the compounds which would not be sufficiently soluble in water. Mention may be made, as organic solvent, for example, of lower C1-C4 alkanols, such as ethanol and isopropanol; polyols and polyol ethers, such as 2-butoxyethanol, propylene glycol, propylene glycol monomethyl ether, diethylene glycol monoethyl ether or diethylene glycol monomethyl ether; and aromatic alcohols, such as benzyl alcohol or phenoxyethanol, and

their mixtures.
The solvents are preferably present in proportions preferably of between 1 and 40% by weight approximately with respect to the total weight of the dyeing composition and more preferably still between 5 and 30% by weight approximately.
The dyeing compositions (A) and/or (B) in accordance with the invention can also include various adjuvants conventionally used in compositions for dyeing the hair, such as anionic, cationic, nonionic, amphoteric or zwitterionic surface-active agents or their mixtures, anionic, cationic, nonionic, amphoteric or zwitterionic polymers or their mixtures, inorganic or organic thickening agents and in particular anionic, cationic, nonionic and amphoteric polymeric associative thickeners, antioxidants, penetration agents, sequestering agents, fragrances, buffers, dispersing agents, conditioning agents, such as, for example, volatile or nonvolatile and modified or unmodified silicones, film-forming agents, ceramides, preservatives or opacifying agents.
The above adjuvants are generally present in an amount, for each of them, of between 0.01 and 20% by weight with respect to the weight of the dyeing compositions (A) and (B) .
Of course, a person skilled in the art will take care to choose this or these optional additional compounds so that the advantageous properties intrinsically attached to the oxidation dyeing composition in accordance with the invention are not, or not substantially, detrimentally affected by the envisaged addition or additions.
The pH of the dyeing compositions (A) and/or (B) is generally between 3 and 12 approximately and preferably

between 5 and 11 approximately. It can be adjusted to the desired value using acidifying or basifying agents generally used in dyeing keratinous fibres or else using conventional buffering systems.
Mention may be made, among acidifying agents, by way of examples, of inorganic or organic acids, such as hydrochloric acid, orthophosphoric acid, sulphuric acid, carboxylic acids, such as acetic acid, tartaric acid, citric acid or lactic acid, or sulphonic acids.
Mention may be made, among basifying agents, by way of examples, of aqueous ammonia, alkaline carbonates, alkanolamines, such as mono-, di- and triethanolamines and their derivatives, sodium hydroxide, potassium hydroxide and the compounds of following formula (III) :
(Formula Removed)
in which W is a propylene residue optionally substituted by a hydroxyl group or a C1-C4 alkyl radical and Ra, Rb, RC and Rd, which are identical or different, represent a hydrogen atom, a C1-C4 alkyl radical or a C1-C4 hydroxyalkyl radical.
The dyeing compositions (A) and/or (B) can be provided in various forms, such as in the form of liquids, creams or gels or in any other form appropriate for carrying out dyeing of keratinous fibres and in particular of human hair.
The mixture of the two compositions (A) and (B) is preferably in a ratio (A) / (B) by weight of between 5/1 and 1/5 and preferably between 3/1 and 1/3. More preferably, the ratio by weight of the (A)/(B) mixture is 1/1.

The mixture can be prepared before or at the time of application to keratinous fibres.
The process of the present invention is a process for colouring keratinous fibres which consists in applying, to the fibres, a mixture of a composition (A) and of a "fundamental" or "golden fundamental" dyeing composition (B);
the said composition (A) comprising at least one coupler chosen from 6-chloro-2-methyl-5-aminophenol and one of its salts and comprising at least one oxidation base derived from the diamino-N,N-dihydropyrazolone of formula (I) or one of its salts,
(Formula Removed)
(I)
in which:
• R1, R2, R3 and R4, which are identical or different,
represent:
a linear or branched C1-C6 alkyl radical optionally substituted by one or more radicals chosen from the group consisting of an OR5 radical, an NR6R7 radical, a carboxyl radical, a sulpho radical, a carboxamido CONR6R7 radical, a sulphonamido S02NR6R7 radical, a heteroaryl or an aryl optionally substituted by one or more (C1-C4)alkyl, hydroxyl, C1-C2 alkoxy, amino or (di) (Ci-C2)alkylamino groups;
an aryl radical optionally substituted by one or more C1-C4 alkyl, hydroxyl, C1-C2 alkoxy, amino or (di) C1-C2 alkylamino groups,-a 5- or 6-membered heteroaryl radical optionally substituted by one or more radicals chosen from C1-C4 alkyl or C1-C2 alkoxy;
• R3 and R4 can also represent a hydrogen atom;

• R5, R6 and R7, which are identical or different,
represent:
a hydrogen atom;
a linear or branched C1-C4 alkyl radical optionally substituted by one or more radicals chosen from hydroxyl, C1-C2 alkoxy, carboxamido CONR8R9, sulphonyl S02R8 or aryl optionally substituted by a C1-C4 alkyl, hydroxyl, C1-C2 alkoxy, amino or (di) C1-C2 alkylamino; or an aryl radical optionally substituted by a C1-C4 alkyl, hydroxyl, C1-C2 alkoxy, amino or (di) C1-C2 alkylamino,-
• R6 and R7, which are identical or different, can
also represent a carboxamido CONR8R9 radical or a
sulphonyl SO2R8 radical;
• R8 and R9, which are identical or different,
represent a hydrogen atom or a linear or branched
C1-C4 alkyl radical optionally substituted by one
or more hydroxyl or C1-C2 alkoxy groups;
• RI and R2, on the one hand, and R3 and R4, on the
other hand, can form, with the nitrogen atom or
atoms to which they are attached, a saturated or
unsaturated 5- to 7-membered heterocycle
optionally substituted by one or more radicals
chosen from the group consisting of halogen atoms,
amino, (di) C1-C4alkylamino, hydroxyl, carboxyl,
carboxamido or C1-C2 alkoxy radicals or C1-C4 alkyl
radicals optionally substituted by one or more
hydroxyl, amino, (di)alkylamino, alkoxy, carboxyl
or sulphonyl radicals;
• R3 and R4 can also form, together with the nitrogen
atom to which they are attached, a 5- or 7-
membered heterocycle, the carbon atoms of which
can be replaced by an oxygen atom or an optionally
substituted nitrogen atom.
According to a specific embodiment, the mixture of the composition (A) and (B) is preferably added at the time of use to a composition comprising, in a medium

appropriate for dyeing, at least one oxidizing agent, this oxidizing agent being present in an amount sufficient to develop a colouring. The mixture obtained is subsequently applied to the keratinous fibres. After a leave-in time of 3 to 50 minutes approximately, preferably 5 to 30 minutes approximately, more preferably 20 minutes, the keratinous fibres are rinsed, washed with a shampoo, rinsed again and then dried.
The oxidizing agents conventionally used for the oxidation dyeing of keratinous fibres are, for example, hydrogen peroxide, urea hydrogen peroxide, alkali metal bromates, persalts, such as perborates and persulphates, peracids and oxidase enzymes, among which may be mentioned peroxidises, 2-electron oxidoreductases, such as uricases, and 4-electron oxygenases, such as laccases. Hydrogen peroxide is particularly preferred.
The oxidizing composition can also include various adjuvants conventionally used in compositions for dyeing the hair and as defined above.
The pH of the oxidizing composition including the oxidizing agent is such that, after mixing with the dyeing composition, the pH of the resulting composition applied to the keratinous fibres preferably varies between 3 and 12 approximately and more preferably still between 5 and 11. It can be adjusted to the desired value using acidifying or basifying agents commonly used in dyeing keratinous fibres and as defined above.
The colour can be developed at acidic, neutral or alkaline pH and the oxidizing agent can be added to the composition of the invention only at the time of use or it can be employed from an oxidizing composition comprising it, applied simultaneously or sequentially

with the mixture of compositions of the invention.
Preferably, this colouring is developed at neutral pH.
The ready-for-use composition which is finally applied to the keratinous fibres can be provided in various forms, such as in the form of liquids, creams or gels or in any form appropriate for carrying out dyeing of keratinous fibres and in particular of human hair.
Another subject-matter of the invention is a dyeing kit or multicompartment device in which a first compartment includes a dyeing composition (A) comprising at least one coupler chosen from 6-chloro-2-methyl-5-aminophenol and one of its salts and also comprising at least one diamino-N, W-dihydropyrazolone oxidation base of formula (I), such as 2,3-diamino-6,7-dihydro-lH,5H-pyrazolo[1,2-a]pyrazol-1-one, a second compartment includes a composition (B) of fundamental or golden fundamental shade and a third compartment includes the oxidizing agent or an oxidizing composition.
This device can be equipped with a means which makes it possible to deliver the desired mixture to the hair, such as the devices described in Patent FR-2 586 913 on behalf of the Applicant Company.
A specific embodiment relates to a dyeing kit as defined above in which the first compartment comprises a dyeing composition (A) of coppery shade, the second compartment comprises a composition (B) of fundamental shade and the final compartment comprises an oxidizing agent.
The examples which follow serve to illustrate the invention without, however, exhibiting a limiting nature.
COLOURING PROCESS EXAMPLE

Composition (A) of the "coppery" shade;

(Table Removed)

Composition (B) of the "golden" shade:

(Table Removed)

Composition (C) of the "coppery" shade, the oxidation base of which derived from diamino-N,N-dihydropyrazolone has been replaced by para-aminophenol, and comprising the specific coupler 6-chloro-2-methyl-5-aminophenol

(Table Removed)

Method of applicaiton and results
At the time of use, the composition (A) or (C) is mixed with the composition (B) in a ratio by weight of 1/1 and then the resulting mixture is mixed with an oxidizing agent in the proportions by weight of 1/1.5 (1+1.5). The oxidizing agent is an oxidizing agent of 25-volume (25 V) hydrogen peroxide type. A pH of approximately 10 is obtained.
The mixtures (A)/(B) or (C)/(B) are applied to locks of grey hair comprising 90% of natural white hairs (NW) in a proportion of 30 g of mixture per 2 g of hair. After leaving for 20 minutes at ambient temperature, the locks are rinsed, washed with a standard shampoo, rinsed again and then dried.

(Table Removed)
Oxidizing agent*: 25-volume hydrogen peroxide

Thus, the mixture of the compositions (A)/(B) colours the keratinous fibres in a predictable way with a coppery shade which completely covers the white hairs.
On the other hand, the mixture of the compositions (C)/(B) colours the fibres blond with undesirable "purplish" shades.
It is thus apparent that the presence of the oxidation base of diamino-N,N-dihydropyrazolone type of formula (I), such as the salt of 2,3-diamino-6,7-dihydro-lH, 5H-pyrazolo[1,2-a]pyrazol-l-one, in the composition (A) makes it possible to prevent an unpredictable colour and/or shade originating from the mixture of "fundamental" or "golden fundamental" with a "shaded" dyeing composition comprising a meta-aminophenol coupler substituted by halogen, including in particular 6 -chloro-2-methyl-5-aminophenol.

CLAIMS
1. Process for colouring keratinous fibres which consists in applying, to the fibres, a mixture of a composition (A) and of a "fundamental" or "golden fundamental" or "golden" dyeing composition (B); the said composition (A) comprising at least one coupler chosen from 6-chloro-2-methyl-5-aminophenol and one of its salts and comprising at least one oxidation base derived from diamino-N,N-dihydropyrazolone of formula (I) or one of its salts,
(I)
in which:
• R1, R2/ R3 and R4, which are identical or different,
represent:
a linear or branched C1-C6 alkyl radical optionally substituted by one or more radicals chosen from the group consisting of an OR5 radical, an NReR? radical, a carboxyl radical, a sulpho radical, a carboxamido CONR6R7 radical, a sulphonamido S02NR6R7 radical, a heteroaryl or an aryl optionally substituted by one or more (C1-C4)alkyl, hydroxyl, C1-C2 alkoxy, amino or (di) (C1-C2)alkylamino groups;
an aryl radical optionally substituted by one or more (C1-C4) alkyl, hydroxyl, C1-C2 alkoxy, amino or (di)(C1-C2)alkylamino groups; - a 5- or 6-membered heteroaryl radical optionally substituted by one or more radicals chosen from (C1-C4) alkyl or (C1-C2) alkoxy;
• R3 and R4 can also represent a hydrogen atom;
• R5, R6 and R7, which are identical or different,
represent:
a hydrogen atom;
a linear or branched C1-C4 alkyl radical

optionally substituted by one or more radicals chosen from hydroxyl, C1-C2 alkoxy, carboxamido CONR8R9, sulphonyl S02Re or aryl optionally substituted by a (C1-C4) alkyl, hydroxyl, C1-C2 alkoxy, amino or (di) C1-C2 alkylamino; or an aryl radical optionally substituted by a (C1-C4)alkyl, hydroxyl, C1-C2 alkoxy, amino or (di) (C1-C2) alkylamino;
• R6 and R7, which are identical or different, can
also represent a carboxamido CONR8Rg radical or a
sulphonyl SO2R8 radical;
• R8 and Rg, which are identical or different,
represent a hydrogen atom or a linear or branched
Ci-C4 alkyl radical optionally substituted by one
or more hydroxyl or C1-C2 alkoxy groups;
• RX and R2, on the one hand, and R3 and R4/ on the
other hand, can form, with the nitrogen atom or
atoms to which they are attached, a saturated or
unsaturated 5- to 7-membered heterocycle
optionally substituted by one or more radicals
chosen from the group consisting of halogen atoms,
amino, (di) (C1-C4)alkylamino, hydroxyl, carboxyl,
carboxamido or C1-C2 alkoxy radicals or C1-C4 alkyl
radicals optionally substituted by one or more
hydroxyl, amino, (di)alkylamino, alkoxy, carboxyl
or sulphonyl radicals;
• R3 and R4 can also form, together with the nitrogen
atom to which they are attached, a 5- or 7-
membered heterocycle, the carbon atoms of which
can be replaced by an oxygen atom or an optionally
substituted nitrogen atom;
in the presence of an oxidizing agent.
2. Colouring process according to the preceding claim, in which the oxidation base of the composition (A) of formula (I) comprises R1 and R2 groups which form, together with the nitrogen atoms to which they are attached, a pyrazolidine or pyridazolidine ring optionally substituted by one or more C1-C4 alkyl

radicals, a hydroxyl, a (C1-C2)alkoxy, a carboxyl, a carboxamido, an amino or a (di) (C1-C2)alkylamino.
3. Colouring process according to either one of the preceding claims, in which the oxidation base of the composition (A) of formula (I) comprises R3 and R4 groups which are chosen from a hydrogen atom; a linear or branched d-C6 alkyl radical optionally substituted by one or more hydroxyl, (C1-C2) alkoxy, amino or (di) (C1-C2)alkylamino radicals; or a phenyl radical optionally substituted by one or more hydroxyl, amino or (C1-C2)alkoxy radicals.
4 . Colouring process according to any one of the preceding claims, in which the oxidation base of the composition (A) is chosen from 2,3-diamino-6,7-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-one and one of its salts.
5. Process according to any one of the preceding
claims, in which the amount by weight of the coupler 6-
chloro-2-methyl-5-aminophenol or one of its salts is
between 0.001 and 8%.
6. Process according to any one of the preceding
claims, in which the amount by weight of oxidation base
of formula (I) of the composition (A) is between 0.001
and 8%.
7. Colouring process according to any one of the
preceding claims, in which the ratio by weight of the
mixture of the composition (A) to the composition (B)
is a ratio (A)/(B) of between 5/1 and 1/5.
8. Colouring process according to any one of the
preceding claims, in which the composition (B) is a
"fundamental" or "golden fundamental" or "golden"
composition chosen so that, in the presence of an
oxidizing agent, it results, at ambient temperature on

a lock of unpermed grey hair comprising 90% of white hairs, in the following values in the L*a*b* colorimetric system:
a* belongs to the range [0; +20], b* belongs to the range [0; +20] and L* belongs to the range [0; +50].
9. Colouring process according to the preceding claim,
in which the composition (B) comprises at least one
oxidation base chosen from para-phenylenediamines and
their salts.
10. Colouring process according to the preceding claim,
in which the para-phenylenediamines and their salts are
chosen from para-toluenediamine, para-phenylenediamine
and their salts.
11. Colouring process according to any one of Claims 8
to 10, in which the oxidation base of the composition
(B)is at a level of less than or equal to 5 mmol per
100 g of composition (B).
12. Colouring process according to any one of the
preceding Claims 8 to 11, in which the composition (B)
comprises at least one coupler chosen from meta-
diphenols, meta-aminophenols and meta-
phenylenediamines.
13. Dyeing kit or multicompartment device in which a
first compartment includes a dyeing composition (A)
comprising at least one diamino-.W/.W-dihydropyrazolone
oxidation base of formula (I) as defined in Claims 1 to
4 and at least one specific coupler chosen from
6-chloro-2-methyl-5-aminophenol and one of its salts, a
second compartment includes a composition (B) of
"fundamental" or "golden fundamental" or "golden" shade
optionally in proportions by weight as defined in
Claim 5 and a third compartment includes the oxidizing
agent or an oxidizing composition.