AU730767B2

AU730767B2 - Composition for the oxidation dyeing of keratin fibres and dyeing process using this composition

Info

Publication number: AU730767B2
Application number: AU76604/98A
Authority: AU
Inventors: Mireille Maubru
Original assignee: LOreal SA
Current assignee: LOreal SA
Priority date: 1997-06-03
Filing date: 1998-05-06
Publication date: 2001-03-15
Anticipated expiration: 2018-05-06
Also published as: PL337155A1; JP3882130B2; CN1198572C; AU7660498A; ES2212299T3; KR20010013181A; EP0988021B1; FR2763841B1; EP0988021A1; FR2763841A1; HUP0002411A2; BR9809532A; HUP0002411A3; JP2000513748A; CA2290681A1; RU2187297C2; DE69819722D1; CN1259039A; WO1998055083A1; DE69819722T2

Abstract

The invention concerns a ready-for-use keratin fibre oxidation dyeing composition, in particular for human keratin fibres such as hair, comprising, in a medium suitable for dyeing, at least a heterocyclic oxidation dye, at least an oxydoreductase enzyme with 2 electrons in the presence of at least a donor for said enzyme, and the dyeing method using said composition.

Description

I*

1 COMPOSITION FOR THE OXIDATION DYEING OF KERATIN FIBRES AND DYEING PROCESS USING THIS COMPOSITION The invention relates to a composition for the oxidation dyeing of keratin fibres, and in particular human keratin fibres such as the hair, comprising, in a medium which is suitable for dyeing, at least one heterocyclic oxidation dye and at least one enzyme of 2-electron oxidoreductase type in the presence of at least one donor for the said enzyme, and to the dyeing process using this composition.

It is known practice to dye keratin fibres, and in particular human hair, with dye compositions containing oxidation dye precursors, in particular ortho- or para-phenylenediamines, ortho- or paraaminophenols and heterocyclic bases, which are generally referred to as oxidation bases. Oxidation dye precursors, or oxidation bases, are colourless or weakly coloured compounds which, when combined with oxidizing products, can give rise to coloured compounds and dyes by a process of oxidative condensation.

It is also known that the shades obtained with these oxidation bases can be varied by combining them with couplers or coloration modifiers, the latter being chosen in particular from aromatic meta-diamines, meta-aminophenols, meta-diphenols and certain heterocyclic compounds.

IV (b f% 2 The variety of molecules used as oxidation bases and couplers allows a wide range of colours to be obtained.

The so-called "permanent" coloration obtained by means of these oxidation dyes must moreover satisfy a certain number of requirements. Thus, it must have no toxicological drawbacks, it must be able to give shades of the desired intensity and it must be able to withstand external agents (light, bad weather, washing, permanent-waving, perspiration, rubbing).

The dyes must also be able to cover white hair and, lastly, they must be as unselective as possible, i.e. they must give the smallest possible coloration differences along the same length of keratin fibre, which may in fact be differently sensitized damaged) between its tip and its root.

The oxidation dyeing of keratin fibres is generally carried out in alkaline medium, in the presence of hydrogen peroxide. However, the use of alkaline media in the presence of hydrogen peroxide has the drawback of causing appreciable degradation of the fibres, as well as bleaching of the keratin fibres, which is not always desirable.

The oxidation dyeing of keratin fibres can also be carried out using oxidizing systems other than hydrogen peroxide, such as enzymatic systems. Thus, it f.

3 has already been proposed to dye keratin fibres, in particular in patent application EP-A-0,310,675, with compositions comprising an oxidation dye precursor of benzenic type, in combination with enzymes such as pyranose oxidase, glucose oxidase or uricase, in the presence of a donor for the said enzymes. Although being used under conditions which do not result in a degradation of the keratin fibres which is comparable to that caused by the dyes used in the presence of hydrogen peroxide, these dyeing processes nevertheless lead to colorations which are less intense.

The Applicant has now discovered that it is possible to obtain novel dyes, which are capable of giving intense colorations without giving rise to any significant degradation or bleaching of keratin fibres, and which are relatively unselective and show good resistance to the various attacking factors to which the hair may be subjected, by combining at least one oxidation base, at least one coupler and at least one enzyme of 2-electron oxidoreductase type in the presence of at least one donor for the said enzyme, the oxidation base(s) and/or the coupler(s) used being chosen from suitably selected heterocyclic compounds.

This discovery forms the basis of the present invention.

A first subject of the invention is thus a 'F

(W

4 ready-to-use composition for the oxidation dyeing of keratin fibres, and in particular human keratin fibres such as the hair, comprising the combination of at least one oxidation base and at least one coupler, characterized in that it comprises, in a medium which is suitable for dyeing, at least one enzyme of 2-electron oxidoreductase type in the presence of at least one donor for the said enzyme, and in that the said oxidation base and/or the said coupler is chosen from heterocyclic compounds with the exclusion of monocyclic pyridine compounds.

The ready-to-use dye composition in accordance with the invention gives colorations which are more intense than those obtained with dye compositions containing only benzenic dyes in the presence of an enzyme of 2-electron oxidoreductase type, and of a donor for the said enzyme, which is not the case with a conventional oxidizing system such as hydrogen peroxide. The colorations obtained with the ready-to-use dye composition in accordance with the invention is moreover relatively unselective and has excellent properties of resistance both with respect to atmospheric agents such as light and bad weather and with respect to perspiration and the various treatments to which the hair may be subjected (washing, permanent waving).

S'

A subject of the invention is also a process for the oxidation dyeing of keratin fibres using this ready-to-use dye composition.

The 2-electron oxidoreductase(s) used in the ready-to-use dye composition in accordance with the invention can be chosen in particular from pyranose oxidases, glucose oxidases, glycerol oxidases, lactate oxidases, pyruvate oxidases and uricases.

According to the invention, the 2-electron oxidoreductase is preferably chosen from uricases of animal, microbiological or biotechnological origin.

By way of example, mention may be made in particular of uricase extracted from boar liver, uricase from Arthrobacter globiformis, as well as uricase from Aspergillus flavus.

The 2-electron oxidoreductase(s) can be used in pure crystalline form or in a form diluted in a diluent which is inert with respect to the said 2-electron oxidoreductase.

The 2-electron oxidoreductase(s) in accordance with the invention preferably represent(s) from 0.01 to 20% by weight approximately relative to the total weight of the ready-to-use dye composition, and even more preferably from 0.1 to 5% by weight approximately relative to this weight.

According to the invention, the term "donor" f, 6 means the various substrates also necessary for the functioning of the said 2-electron oxidoreductase(s).

The nature of the donor (or substrate) for the said enzyme varies depending on the nature of the 2-electron oxidoreductase used. For example, as donors for pyranose oxidases, mention may be made of D-glucose, L-sorbose and D-xylose; as a donor for glucose oxidases, mention may be made of D-glucose; as a donor for glycerol oxidases, mention may be made of glycerol and dihydroxyacetone; as donors for lactate oxidases, mention may be made of lactic acid and its salts; as donors for pyruvate oxidases, mention may be made of pyruvic acid and its salts; and finally, as donors for uricases, mention may be made of uric acid and its salts.

The donor(s) (or substrate(s)) used in accordance with the invention preferably represent(s) from 0.01 to 20% by weight approximately relative to the total weight of the ready-to-use dye composition in accordance with the invention, and even more preferably from 0.1 to 5% by weight approximately relative to this weight.

Among the heterocyclic oxidation bases which can be used in the ready-to-use dye composition according to the invention, mention may be made in particular of pyrimidine derivatives and pyrazole 11 .1 f 7 derivatives, and the addition salts thereof with an acid.

Among the pyrimidine derivatives, mention may be made more particularly of the compounds described, for example, in German patent DE 2,359,399 or Japanese patents JP 88-169,571 and JP 91-106,059, such as 2,4,5,6-tetraamiriopyrimidine, 4-hydroxy-2,5,6-triaminopyrimidine and the addition salts thereof with an acid, as well as pyrazolopyrimidine derivatives such as pyrazolo[l,5-a]pyrimidine-3,7-diamine, 2-methylpyrazolo pyrimidine-3, 7-diamine, 2,5-dimethylpyrazolo[1,5-alpyrimidine-3,7-diamine, pyrazolo 5-a] pyrimidine-3, 2,7-dimethylpyrazolo[1,5-alpyrimidine-3,5-diamine, 3-aminopyrazolo[l,5-a]pyrimidin-7-ol, 3-amino- 5-methylpyrazolo[1,5-alpyrimidin-7-ol, 3-aminopyrazolo[1,5-alpyrimidin-5-ol, 2- (3-aminopyrazolo [1,5-a]pyrimidin-7-ylamino) ethanol, 3 -amino-7- 3-hydroxyethylamino-5-methylpyrazolo[1,5-a] pyrimidine, 2- (7-aminopyrazolo[1,5-alpyrimidin- 3-ylamino)ethanol, 2- [(3-aminopyrazolo [1,5-al pyrimidin- 7-yl) (2-hydroxyethyl)amino] ethanol, 2- [(7-aminopyrazolo pyrirnidin- 3-yl) (2-hydroxyethyl)amino] ethanol, 5, 6 -dimethylpyrazolo[1,5-a]pyrirnidine-3,7-diamine, 2,6-dimethylpyrazolo[l, 5-alpyrirnidine-3,7-diamine and 8 2,5-N-7,N-7-tetramethylpyrazolo[1,5-a]pyrimidine- 3,7-diamine, and the addition salts thereof and the tautomers thereof, when a tautomeric equilibrium exists.

Among the pyrazole derivatives, mention may be made more particularly of the compounds described in patents or patent applications DE 3,843,892, DE 4,133,957, DE 4,234,886, DE 4,234,887, FR 2,733,749, FR 2,735,685, WO 94/08969 and WO 94/08970, such as 4,5-diaminopyrazole, 3,4-diaminopyrazole, l-benzyl-4,5-diamino-3-methylpyrazole, 4-amino- 1,3-dimethyl-5-hydrazinopyrazole, 4,5-diamino-3-methyl- 1-phenylpyrazole, 4,5-diamino-3-methyl-1-tertbutylpyrazole, 4,5-diamino-l-methyl-3-tertbutylpyrazole, 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-l-methylpyrazole, 4,5-diamino-3-hydroxymethyl-l-isopropylpyrazole and 4,5-diamino-3-methyl-l-isopropylpyrazole, and the addition salts thereof with an acid.

When they are present, the heterocyclic oxidation base(s) in accordance with the invention preferably represent(s) from 0.0005 to 12% by weight approximately relative to the total weight of the

I.

9 ready-to-use dye composition, and even more preferably from 0.005 to 6% by weight approximately relative to this weight.

Among the heterocyclic couplers which can be used in the ready-to-use dye composition according to the invention, mention may be made in particular of indole derivatives, indoline derivatives, benzimidazole derivatives, benzomorpholine derivatives, sesamol derivatives, pyrazoloazole derivatives, pyrroloazole derivatives, imidazoloazole derivatives, pyrazolopyrimidine derivatives, derivatives, pyrrolo[3,2-d]oxazole derivatives, pyrazolo[3,4-d]thiazole derivatives, thiazoloazole S-oxide derivatives and thiazoloazole S,S-dioxide derivatives, and the addition salts thereof with an acid.

Among the indole derivatives which can be used as heterocyclic couplers in the dye composition in accordance with the invention, mention may be made more particularly of the compounds of formula below, and the addition salts thereof with an acid:

X

R

3 R2 Ri in which: RI represents a hydrogen atom, a Ci-C, alkyl radical, a

C

2

-C

4 mono- or polyhydroxyalkyl radical or a

C,-C

4 aminoalkyl radical in which the amine is mono- or disubstituted with a Cl-C 4 alkyl group;

R

2 represents a hydrogen atom or a Cl-C, alkyl radical;

R

3 represents a hydrogen atom or a Cl-C 4 alkyl or hydroxyl radical; X represents a hydroxyl radical or a radical NHR 4 in which R 4 represents a hydrogen atom or a Cl-C, alkyl or

C

1

-C

4 hydroxyalkyl radical.

Among the indole compounds of formula (I) above, mention may be made more particularly of 4-hydroxyindole, 6-hydroxyindole, 7-aminoindole, 6-aminoindole, 7-hydroxyindole, 7-ethyl- 6-(3-hydroxyethyl)aminoindole, 4-aminoindole, 6-hydroxy-l-methylindole, 5,6-dihydroxyindole, 4-hydroxy-l-N-methylindole, 4-hydroxy-2-methylindole, 4-hydroxy-l-N- ((-hydroxyethyl)indole, 4-hydroxy- 1-N- (-hydroxypropyl)indole, 1-N-(3,y-dihydroxypropyl)- 4-hydroxyindole, 4-hydroxy-1-N- (-hydroxyethyl) and 1-N-(y-dimethylaminopropyl)- 4-hydroxyindole, and the addition salts thereof with an acid.

Among the indoline derivatives which can be used as heterocyclic couplers in the dye composition in accordance with the invention, mention may be made in particular of 4-hydroxyindoline, 6-hydroxyindoline, 6-aminoindoline and 5,6-dihydroxyindoline, and the addition salts thereof with an acid.

Among the benzimidazole derivatives which can be used as heterocyclic couplers in the dye composition in accordance with the invention, mention may be made more particularly of the compounds of formula (II) below, and the addition salts thereof with an acid:

R

7 R (R 6 I)

RR

in which: Rs represents a hydrogen atom or a Ci-C, alkyl radical,

R

6 represents a hydrogen atom or a Cl-C 4 alkyl or phenyl radical, R, represents a hydroxyl, amino or methoxy radical, R, represents a hydrogen atom or a hydroxyl, methoxy or

C

1

-C

4 alkyl radical; with the proviso that: when R, denotes an amino radical, then it occupies position 4, when R, occupies position 4, then R 8 occupies position 7, when R, occupies position 5, then R 8 occupies position 6.

Among the benzimidazole derivatives of formula (II) above, mention may be made more particularly of 4-hydroxybenzimidazole, 4-aminobenzimidazole, 4-hydroxy-7-methylbenzimidazole, 4-hydroxy-2-methylbenzimidazole, 1-butyl-4-hydroxybenzimidazole, 4-amino-2-methylbenzimidazole, 5,6-dihydroxybenzimidazole, 5-hydroxy-6-methoxybenzimidazole, 4,7-dihydroxybenzimidazole, 4,7-dihydroxyl-methylbenzimidazole, 4,7-dimethoxybenzimidazole, 5,6-dihydroxy-l-methylbenzimidazole, 5,6-dihydroxy- 2-methylbenzimidazole and 5,6-dimethoxybenzimidazole, and the addition salts thereof with an acid.

Among the benzomorpholine derivatives which can be used as heterocyclic couplers in the ready-touse dye composition in accordance with the invention, mention may be made more particularly of the compounds of formula (III) below, and the addition salts thereof with an acid: 0 Z N in which: R, and Ro, which may be identical or different, represent a hydrogen atom or a alkyl radical, Z represents a hydroxyl or amino radical.

Among the benzomorpholine derivatives of formula (III) above, mention may be made more particularly of 6-hydroxy-1,4-benzomorpholine, N-methyl-6-hydroxy-l,4-benzomorpholine and 6-amino- 1,4-benzomorpholine, and the addition salts thereof with an acid.

Among the sesamol derivatives which can be used as heterocyclic coupler in the ready-to-use dye composition in accordance with the invention, mention may be made more particularly of the compounds of formula (IV) below, and the addition salts thereof with an acid:

R

1 1

R

1 2 I, (IV) 0 in which: R, denotes a hydroxyl, amino, (C,-C 4 )alkylamino, monohydroxy (Cl-C 4 alkylamino or polyhydroxy (C 2

-C

4 )alkylamino radical,

R

12 denotes a hydrogen or halogen atom or a C 1 alkoxy radical.

1 14 Among the sesamol derivatives of formula (IV) above, mention may be made more particularly of 2-bromo-4,5-methylenedioxyphenol, 2-methoxyand 2- (-hydroxyethyl)amino- 4,5-methylenedioxybenzene, and the addition salts thereof with an acid.

Among the pyrazoloazole derivatives which can be used as heterocyclic couplers in the ready-to-use dye composition in accordance with the invention, mention may be made more particularly of the compounds described in the following patents and patent applications: FR 2,075,583, EP-A-119,860, EP-A-285,274, EP-A-244,160, EP-A-578,248, GB 1,458,377, US 3,227,554, US 3,419,391, US 3,061,432, US 4,500,630, US 3,725,067, US 3,926,631, US 5,457,210, JP 84/99437, JP 83/42045, JP 84/162548, JP 84/171956, JP 85/33552, JP 85/43659, JP 85/172982, JP 85/190779 and in the following publications: Chem. Ber. 32, 797 (1899), Chem. Ber. 89, 2550, (1956), J. Chem. Soc. Perkin trans I, 2047, (1977), J. Prakt. Chem., 320, 533, (1978); the teachings of which form an integral part of the present application.

As pyrazoloazole derivatives, mention may be made most particularly of: 2-methylpyrazolo[l,5-b]-1,2,4-triazole, 2-ethylpyrazolo[1,5-b]-1,2,4-triazole, 1.

2-isopropylpyrazolo[1,5-b]-1,2,4-triazole, 2-phenylpyrazolo[l,5-b]-1,2,4-triazole, 2,6-dimethylpyrazolo[l,5-b]-1,2,4-triazole, 7-chloro-2,6-dimethylpyrazolo[l,5-b]-1,2,4-triazole, 3,6-dimethylpyrazolo[3,2-c]-1,2,4-triazole, 6-phenyl-3-methylthiopyrazolo[3,2-c]-1,2,4-triazole and and the addition salts thereof with an acid.

Among the pyrroloazole derivatives which can be used as heterocyclic couplers in the ready-to-use dye composition in accordance with the invention, mention may be made more particularly of the compounds described in the following patents and patent applications: US 5,256,526, EP-A-557,851, EP-A-578,248, EP-A-518,238, EP-A-456,226, EP-A-488,909, EP-A-488,248, and in the following publications: D.R. Liljegren Ber. 1964, 3436; E.J. Browne, 1962, 5149; P. Magnus, 1990, 112, 2465; P. Magnus, 1987, 109, 2711; Angew. Chem. 1960, 72, 956; and Rec. Tray. Chim. 1961, 80, 1075; the teachings of which form an integral part of the present application.

As pyrroloazole derivatives, mention may be made most particularly of: 16 5-cyano-4-ethoxycarbonyl-8-methylpyrrolo[l,2-b]- 1,2,4-triazole, 5-cyano-8-methyl-4-phenylpyrrolo[l,2-b]- 1,2,4-triazole, 7-amido-6-ethoxycarbonylpyrrolo [1,2-a]-benzimidazole, and the addition salts thereof with an acid.

Among the imidazoloazole derivatives which can be used as heterocyclic couplers in the ready-touse dye composition in accordance with the invention, mention may be made more particularly of the compounds described in the following patents and patent applications: US 5,441,863; JP 62-279,337; JP 06-236,011 and JP 07-092,632, the teachings of which form an integral part of the present application.

As imidazoloazole derivatives, mention may be made most particularly of: 7,8-dicyanoimidazolo[3,2-a]imidazole, 7,8-dicyano-4-methylimidazolo[3,2-a]imidazole, and the addition salts thereof with an acid.

Among the pyrazolopyrimidine derivatives which can be used as heterocyclic couplers in the ready-to-use dye composition in accordance with the invention, mention may be made more particularly of the compounds described in the following patent application: EP-A-304,001, the teaching of which forms an integral part of the present application.

17 As pyrazolopyrimidine derivatives, mention may be made most particularly of: pyrazolo[1,5-a]pyrimidin-7-one, 2,5-dimethylpyrazolo[l,5-a]pyrimidin-7-one, 2-methyl-6-ethoxycarbonylpyrazolo[1,5-a]pyrimidin- 7-one, 2-methyl-5-methoxymethylpyrazolo[1,5-a]pyrimidin- 7-one, 2-tert-butyl-5-trifluoromethylpyrazolo[1,5-a]pyrimidin-7-one, 2,7-dimethylpyrazolo[1,5-a]pyrimidin-5-one, and the addition salts thereof with an acid.

Among the pyrazoline-3,5-dione derivatives which can be used as heterocyclic couplers in the ready-to-use dye composition in accordance with the invention, mention may be made more particularly of the compounds described in the following patents and patent applications: JP 07-036159, JP 07-084348 and US 4,128,425, and in the following publications: L. WYZGOWSKA, Acta. Pol. Pharm. 1982, 39 83 E. HANNIG, Pharmazie, 1980, 35 231 M.H. ELNAGDI, Bull. Chem. Soc. Jap., 46 1830, 1973 G. CARDILLO, Gazz. Chim. Ital. 1966, 96, 973, the teachings of which form an integral part of the present application.

n 18 As pyrazoline-3,5-dione derivatives, mention may be made most particularly of: 1,2-diphenylpyrazoline-3,5-dione, 1,2-diethylpyrazoline-3,5-dione, and the addition salts thereof with an acid.

Among the pyrrolo[3,2-d]oxazole derivatives which can be used as heterocyclic couplers in the ready-to-use dye composition in accordance with the invention, mention may be made more particularly of the compounds described in patent application JP 07-325,375, the teaching of which forms an integral part of the present application.

Among the pyrazolo[3,4-d]thiazole derivatives which can be used as heterocyclic couplers in the ready-to-use dye composition in accordance with the invention, mention may be made more particularly of the compounds described in patent application JP 07-244,361 and in J. Heterocycl. Chem. 16, 13, (1979).

Among the thiazoloazole S-oxide and thiazoloazole S,S-dioxide derivatives which can be used as heterocyclic couplers in the ready-to-use dye composition in accordance with the invention, mention may be made more particularly of the compounds described in the following documents: JP 07-098489; Khim. Geterotsilk. Soedin, 1967, p. 93; J. Prakt. Chem., 318, 1976, p. 12; Indian J. Heterocycl. Chem. 1995, 5, p. 135; Acta. Pol. Pharm. 1995, 52 415; Heterocycl. Commun. 1995, 1 297; Arch. Pharm. (Weinheim, Ger.), 1994, 327 825.

When they are present, this or these heterocyclic coupler(s) preferably represent(s) from 0.0001 to 10% by weight approximately relative to the total weight of the ready-to-use dye composition and even more preferably from 0.005 to 5% by weight approximately relative to this weight.

The ready-to-use dye composition in accordance with the invention can also contain, in addition to the dyes defined above, other oxidation bases and/or other couplers and/or other dyes such as, for example, direct dyes, in particular to modify the shades or to enrich them with glints.

Among the oxidation bases which can additionally be present in the ready-to-use dye composition in accordance with the invention, mention may be made in particular of para-phenylenediamines, bis(phenyl)alkylenediamines, ortho-phenylenediamines, para-aminophenols and ortho-aminophenols, and the addition salts thereof with an acid.

When they are used, these additional oxidation bases preferably represent from 0.0005 to 12% by weight approximately relative to the total weight of the dye composition and even more preferably from 0.005 to 6% by weight approximately relative to this weight.

Among the couplers which can additionally be present in the ready-to-use dye composition in accordance with the invention, mention may be made in particular of meta-phenylenediamines, meta-aminophenols and meta-diphenols, and the addition salts thereof with an acid.

When they are present, these additional couplers preferably represent from 0.0001 to 10% by weight approximately relative to the total weight of the ready-to-use dye composition and even more preferably from 0.005 to 5% by weight approximately relative to this weight.

In general, the addition salts with an acid o which can be used in the context of the dye compositions of the invention (oxidation bases and couplers) are chosen in particular from the hydrochlorides, hydrobromides, sulphates, tartrates, lactates and acetates.

The medium which is suitable for dyeing (or support) for the ready-to-use dye composition in accordance with the invention generally consists of water or a mixture of water and at least one organic solvent to dissolve the compounds which would not be sufficiently soluble in water. By way of organic solvents, mention may be made, for example, of Ci-C 4 alkanols, such as ethanol and isopropanol; glycerol; glycols and glycol ethers such as 2-butoxyethanol, propylene glycol, propylene glycol monomethyl ether, diethylene glycol monoethyl ether and monomethyl ether, and aromatic alcohols such as benzyl alcohol or phenoxyethanol, similar products and mixtures thereof.

The solvents can be present in proportions preferably of between 1 and 40% by weight approximately relative to the total weight of the dye composition, and even more preferably between 5 and 30% by weight approximately.

The pH of the ready-to-use composition in accordance with the invention is chosen such that the enzymatic activity of the 2-electron oxidoreductase is not adversely affected. It is generally between 5 and 11 approximately and preferably between 6.5 and approximately. It can be adjusted to the desired value using acidifying or basifying agents usually used for dyeing keratin fibres.

Among the acidifying agents, mention may be made, by way of example, 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, and sulphonic acids.

Among the basifying agents, mention may be made, by way of example, of aqueous ammonia, alkaline carbonates, alkanolamines such as mono-, di- and triethanolamine, 2-methyl-2-aminopropanol and derivatives thereof, sodium hydroxide, potassium hydroxide and the compounds of formula below:

R

13 N-W-N (V)

R

1 4 R 16 in which W is a propylene residue optionally substituted with a hydroxyl group or a C,-C 4 alkyl radical; R 3

R

4

R

1 and R 16 which may be identical or different, represent a hydrogen atom or a Cl-C, alkyl or Cz-C 4 hydroxyalkyl radical.

The ready-to-use dye composition in accordance with the invention can also contain various adjuvants used conventionally in compositions for dyeing the hair, such as anionic, cationic, nonionic, amphoteric or zwitterionic surfactants or mixtures thereof, anionic, cationic, nonionic, amphoteric or zwitterionic polymers or mixtures thereof, inorganic or organic thickeners, antioxidants, enzymes other than the 2-electron oxidoreductases used in accordance with

P

23 the invention, such as, for example, peroxidases, penetrating agents, sequestering agents, fragrances, buffers, dispersing agents, conditioners, such as, for example, silicones, film-forming agents, preserving agents and opacifiers.

Needless to say, a person skilled in the art will take care to select this or these optional additional compound(s) such that the advantageous properties intrinsically associated with the ready-touse dye composition in accordance with the invention are not, or are not substantially, adversely affected by the addition or additions envisaged.

The ready-to-use dye composition in accordance with the invention can be in various forms, such as in the form of liquids, creams or gels, which may be pressurized, or in any other form which is suitable for dyeing keratin fibres, and in particular human hair. In this case, the oxidation dye(s) and the 2-electron oxidoreductase(s) are present in the same ready-to-use composition, and consequently the said composition must be free of gaseous oxygen, so as to avoid any premature oxidation of the oxidation dye(s).

A subject of the invention is also a process for dyeing keratin fibres, and in particular human keratin fibres such as the hair, using the ready-to-use dye composition as defined above.

According to this process, at least one ready-to-use dye composition as defined above is applied to the fibres, for a period which is sufficient to develop the desired coloration, after which the fibres are rinsed, optionally washed with shampoo, rinsed again and dried.

The time required to develop the coloration on the keratin fibres is usually between 3 and minutes and even more precisely between 5 and 40 minutes.

According to one specific embodiment of the invention, the process includes a preliminary step which consists in separately storing, on the one hand, a composition comprising, in a medium which is suitable for dyeing, at least one heterocyclic oxidation base as defined above and/or at least one heterocyclic coupler as defined above, and, on the other hand, a composition comprising, in a medium which is suitable for dyeing, at least one enzyme of 2-electron oxidoreductase type in the presence of at least one donor for the said enzyme, and then in mixing them together at the time of use, after which this mixture is applied to the keratin fibres.

The compositions A and B in accordance with the invention can be packaged in a multi-compartment dyeing device or multi-compartment dyeing "kit" or any other multi-compartment packaging system, a first compartment of which contains composition as defined above and a second compartment of which contains composition as defined above. These devices can be equipped with a means for delivering the desired mixture onto the hair, such as the devices described in patent FR-2,586,913 in the name of the Applicant.

The examples which follow are intended to illustrate the invention without thereby limiting its scope.

EXAMPLES

COMPARATIVE EXAMPLES 1 AND 2 The ready-to-use dye compositions below were prepared (contents in grams): COMPOSITION 2 para-Phenylenediamine (benzenic 0.324 oxidation base) 2,4,5,6-Tetraaminopyrimidine sulphate 0.714 (heterocyclic oxidation base) Resorcinol (benzenic coupler) 0.33 0.33 Uricase from Arthrobacter globiformis, at 20 International Units 1.5 sold by the company Sigma Uric acid 1.5 Common dye support Demineralized water qs 100 g 100 g Example not forming part of the invention Common dye support: Ethanol Hydroxypropyl guar gum sold under the name Jaguar HP 60 by the company Mayhall Poly(C 8

-C

10 )alkylglucoside as an aqueous solution containing 60% active material buffered with ammonium citrate sold under the name Oramix CG110 by the company SEPPIC Monoethanolamine qs 10.0 g 0.8 g 8.0 g pH It is important to note that each of the ready-to-use dye compositions described above contains the same molar amount of each of the oxidation bases, i.e. 3 x 10- 3 mol.

Each of the ready-to-use dye compositions described above was applied to locks of natural grey hair containing 90% white hairs, for 30 minutes. The hair was then rinsed, washed with a standard shampoo and then dried.

The colour of the locks was then evaluated before and after dyeing in the Munsell system using a Minolta CM 2002 colorimeter so as to determine the intensity of the colorations obtained with each of the compositions described above.

The difference between the colour of the lock before dyeing and the colour of the lock after dyeing was calculated by applying the Nickerson formula: AE 0.4 CoAH 6AV 3AC as described, for example, in "Couleur, Industrie et Technique [Colour, Industry and Technology]"; pages 14-17; Vol. No. 5; 1978.

In this formula, AE represents the difference in colour between two locks, AH, AV and AC represent the variation in the absolute value of the parameters H, V and C, and Co represents the purity of the lock relative to which it is desired to evaluate the difference in colour.

The intensity of the coloration (AE) is proportionately greater the larger the figure indicated.

The results are given in Table I below: Table I Colour of the Colour of the Intensity of the EXAMPLE hair before hair coloration dyeing after dyeing AH AV AC AE 3.2 Y 5.0/1.6 3.2 Y 3.6/2.2 0 1.4 0.6 10.2 2 3.2 Y 5.0/1.6 8.3 R 3.7/2.9 14.9 1.3 1.3 21.2 Example not forming part of the invention.

These results show that, in the presence of the uricase/uric acid oxidizing system, the ready-touse dye composition of Example 1 not forming part of the invention, since it does not contain a heterocyclic oxidation dye, gives a coloration which is markedly 28 less intense than that of the ready-to-use dye composition of Example 2 in accordance with the invention which contains at least one heterocyclic compound, i.e. a heterocyclic oxidation base which is 2,4,5,6-tetraaminopyrimidine.

COMPARATIVE EXAMPLES 3 AND 4 The ready-to-use dye compositions below were prepared (contents in grams): COMPOSITION .0 para-Phenylenediamine (benzenic 0.648 oxidation base) 2,4,5,6-Tetraaminopyrimidine sulphate 1.428 (heterocyclic oxidation base) Resorcinol (benzenic coupler) 0.66 0.66 Common dye support Demineralized water qs 100 g 100 g Example not forming part of the invention Common dye support: Ethanol Hydroxypropyl guar gum sold under the name Jaguar HP 60 by the company Mayhall Poly(C 8 -Co 0 )alkylglucoside as an aqueous solution containing 60% active material buffered with ammonium citrate sold under the name Oramix CG110 by the company SEPPIC Monoethanolamine qs 20.0 g 1.6 g 8.0 g pH It is important to note that each of the

II

29 ready-to-use dye compositions described above contains the same molar amount of each of the oxidation bases, i.e. 6 x 10 3 mol.

At the time of use, each of the ready-to-use dye compositions described above was mixed with an equal amount by weight of a 20-volume hydrogen peroxide solution by weight).

Each of the resulting mixtures was applied to locks of natural grey hair containing 90% white hairs, for 30 minutes. The locks of hair were then rinsed, washed with a standard shampoo, rinsed again and then dried.

As described before for Examples 1 and 2 above, the coloration was evaluated in the Munsell system, before and after dyeing, using a Minolta CM2002 colorimeter.

The intensity of the coloration was calculated by applying the Nickerson formula.

The results are collated in Table II below: Table II Colour of the Colour of the Intensity of the EXAMPLE hair before hair coloration dyeing after dyeing AH AV AC 8E 2.9 Y 5.9/1.5 9.3 YR 3.6 3.4 0.3 23.5 2.5/1.2 2.9 Y 5.9/1.5 2.5 YR 10.4 1.5 1.5 19.7 4.4/3.0 Example not forming part of the invention.

In contrast with what was demonstrated before for the Comparative Examples 1 and 2, these results show that by using a conventional oxidizing system not forming part of the invention, such as, for example, hydrogen peroxide in this case, the replacement of a benzenic dye with a heterocyclic dye (in this case para-phenylenediamine was replaced with 2,4,5,6-tetraaminopyrimidine) does not make it possible to increase the intensity of the colorations obtained.

COMPARATIVE EXAMPLES 5 AND 6 The ready-to-use dye compositions below were prepared (contents in grams): COMPOSITION 6 dihydrochloride 0.546 (oxidation base outside the invention) 2,4,5,6-Tetraaminopyrimidine sulphate 0.714 (heterocyclic oxidation base) Resorcinol (benzenic coupler) 0.33 0.33 Uricase from Arthrobacter globiformis, at 20 sold by the company 1.0 Sigma Uric acid 1.0 Common dye support Demineralized water qs 100 g 100 g Example not forming part of the invention Common dye support: This is identical to the one used for Examples 1 and 2 above.

It is important to note that each of the ready-to-use dye compositions described above contains the same molar amount of each of the oxidation bases, i.e. 3 x 10- 3 mol.

As described before for Examples 1 and 2 above, the coloration was evaluated in the Munsell system, before and after dyeing, using a Minolta CM 2002 colorimeter.

The results are collated in Table III below: Table III Colour of the Colour of the Intensity of the EXAMPLE hair before hair coloration dyeing after dyeing AH AV AC AE 2.9 Y 5.9/1.5 4.8 YR 8.1 1.1 0.6 13.3 4.8/2.1 6 2.9 Y 5.9/1.5 10.0 R 12.9 1.2 1.1 18.2 4.7/2.6 Example not forming part of the invention.

These results show that, in the presence of the uricase/uric acid oxidizing system, the ready-touse dye composition of Example 5 not forming part of the invention, since it contains which is a monocyclic pyridine oxidation base outside the invention, gives a coloration which is markedly less intense than that of the ready-to-use dye composition of Example 6 in accordance with the 32 invention which contains at least one heterocyclic compound in accordance with the invention, i.e. a heterocyclic oxidation base which is 2,4,5,6-tetraaminopyrimidine.

EXAMPLES 7 TO 13 OF DYEING The ready-to-use dye compositions below in accordance with the invention were prepared (contents in grams): EXAMPLE 7 8 9 10 11 12 13 Pyrazolo[l,5-alpyrimidine-3,7-diamine 0.666 0.666 dihydrochioride 3 -Amino-7-13-hydroxyethylamino-5- 0.729 methylpyrazolo 5-alpyrimidine hydrochloride____________ para- Phenylenediamine 0.216 0.216 4,5-Diamino-l-ethyl-3-methylpyrazole 0.639 0.639 dihydrochioride 0.369 6-Hydroxy-l, 4-benzomorpholine 0.453 1-Methyl-2-hydroxy-4- U3-hydroxyethyl) aminobenzene 0.501 2-Methoxy-4..5-methylenedioxyalilile hydrochloride I- 0.407 2,6-Dimethylpyra zolo[l,5-bI-l,2,4-triazole para- 0.617 toluenesuiphonate meta -Aminophenol 0.327 l-1-Hydroxyethyloxy-2,4-diaminobenzene 0.723 dihydrochloride Uricase from Arthrobacter globiformis at 0.8 1.2 1.0 0.8 1.0 2.0 1.8 I.U./mg, sold by the company Uric acid 1.2 1.5 2.0 0.8 1.5 2.0 Common dye support(*)(* Demineralized water qs 100100 b g 1b00g b00g b00g b00g b00g Common dye support: This is identical to the one used for Examples 1 and 2 above.

Each of the ready-to-use dye compositions described above was applied to locks of natural or permanent-waved grey hair containing 90% white hairs, for 30 minutes. The hair was then rinsed, washed with a standard shampoo and then dried.

The locks of hair were dyed in the shades given in Table IV below.

Table IV 0000

S.

005 0*

S

OS.

00...

0 0000

S

EXAMPLE Shade obtained on Shade obtained on natural hair permanent-waved hair 7 Golden iridescent Golden iridescent 8 Iridescent Iridescent 9 Coppery iridescent Coppery iridescent 10 Golden ash Matt ash 11 Intense iridescent Intense iridescent 12 Dark purple Dark purple 13 Violet Violet Throughout the specification and claims, the words "comprise", "comprises" and "comprising" are used in a non-exclusive sense.

Claims

1. Ready-to-use composition for the oxidation dyeing of keratin fibres, comprising the combination of at least one oxidation base and at least one coupler, characterised in that it comprises, in a medium which is suitable for dyeing, at least one enzyme of 2-electron oxidoreductase type in the presence of at least one donor for the said enzyme, and in that the said oxidation base and/or the said coupler is chosen from heterocyclic compounds with the exclusion of monocyclic pyridine compounds.

2. Composition according to Claim 1, characterized in that the 2-electron oxidoreductase is 15 chosen from uricases of animal, microbiological or biotechnological origin.

3. Composition according to Claim 1 or 2, •characterized in that the 2-electron oxidoreductase(s) represent(s) from 0.01 to 20% by weight relative to the 20 total weight of the ready-to-use dye composition.

4. Composition according to Claim 3, characterized in that the 2-electron oxidoreductase(s) represent(s) from 0.1 to 5% by weight relative to the total weight of the ready-to-use dye composition.

5. Composition according to Claim 2, characterized in that the donor (or substrate) for the said 2-[lacuna] oxidoreductase is chosen from uric acid and its salts.

6. Composition according to any one of the preceding claims, characterized in that the donor(s) represent(s) from 0.01 to 20% by weight relative to the total weight of the ready-to-use dye composition.

7. Composition according to Claim 6, characterized in that the donor(s) represent(s) from 0.1 to 5% by weight relative to the total weight of the ready-to-use dye composition.

8. Composition according to any one of the preceding claims, characterized in that the heterocyclic oxidation base(s) is (are) chosen from pyrimidine derivatives and pyrazole derivatives, and the addition salts thereof with an acid.

9. Composition according to Claim 8, characterized in that the pyrimidine derivatives are chosen from 2,4,5,6-tetraaminopyrimidine, 4-hydroxy- 2,5,6-triaminopyrimidine and pyrazolopyrimidine derivatives, and the addition salts thereof with an acid.

Composition according to Claim 9, characterized in that the pyrazolopyrimidine derivatives are chosen from 3,7-diamine, 2-methylpyrazolo[1,5-a]pyrimidine- 3,7-diamine, 2,5-dimethylpyrazolo[1,5-a]pyrimidine- 3,7-diamine, pyrazolo[l,5-alpyrimidine-3,5-diamine, 2, 7-dimethylpyrazolo pyrimidine-3, 3-aminopyrazolo[l,5-alpyrimidin-7-ol, 3-amino- [1,5-al pyrimidin-7-ol, 3-aminopyrazolo[1,5-alpyrimidin-5-ol, 2- (3-aminopyrazolo [l,5-alpyrimidin-7-ylamino) ethanol, 3-amino-7-f3-hydroxyethylamino-5-methylpyrazolo[1,l5-a] pyrimidine, 2- (7-aminopyrazolo 3-ylamino)ethanol, 2- [(3-aminopyrazolo pyrimidin- 7-yl) (2-hydroxyethyl) amino] ethanol, 2- [(7-aminopyrazolo[1,5-alpyrimidin- 3-yl) (2-hydroxyethyl) amino] ethanol, 5,6-dimethylpyrazolo[l,5-alpyrimidine-3,7-diamine, 2,6-dimethylpyrazolo[1,5-alpyrimidine-3,7-diamine and 2,5-N-7,N-7-tetramethylpyrazolo[l,5-alpyrimidine- 3,7-diamine, and the addition salts thereof and the tautomers thereof, when a tautomeric equilibrium exists.

11. Composition according to Claim 8, characterized in that the pyrazole derivatives are chosen from 4,5-diaminopyrazole, 1-methylpyrazole, l-benzyl-4, 3,4-diaminopyrazole, 1-benzyl-4,5-diamino- 3-methylpyrazole, 4-amino-1, 3-dimethyl- 5-hydrazinopyrazole, 4, 5-diamino-3-methyl- 1-phenylpyrazole, 4,5-diamino-3-methyl-l-tert- butylpyrazole, 4,5-diamino-l-methyl-3-tert- butylpyrazole, 4,5-diamino-1-ethyl-3-methylpyrazole, 4,5-diamino-1-ethyl-3-(4'-methoxyphenyl)pyrazole, 4,5-diamino-1-ethyl-3-hydroxymethylpyrazole, 4,5-diamino-3-hydroxymethyl-l-methylpyrazole, 4,5-diamino-3-hydroxymethyl-l-isopropylpyrazole and 4,5-diamino-3-methyl-l-isopropylpyrazole, and the addition salts thereof with an acid.

12. Composition according to any one of the preceding claims, characterized in that the heterocyclic oxidation base(s) represent(s) from 0.0005 to 12% by weight relative to the total weight of the ready-to-use dye composition.

13. Composition according to Claim 12, characterized in that the heterocyclic oxidation base(s) represent(s) from 0.005 to 6% by weight relative to the total weight of the ready-to-use dye composition.

14. Composition according to any one of the preceding claims, characterized in that the heterocyclic coupler(s) is (are) chosen from indole derivatives, indoline derivatives, benzimidazole derivatives, benzomorpholine derivatives, sesamol derivatives, pyrazoloazole derivatives, pyrroloazole derivatives, imidazoloazole derivatives, pyrazolopyrimidine derivatives, derivatives, pyrrolo[3,2-d]oxazole derivatives, pyrazolo[3,4-d]thiazole derivatives, thiazoloazole S-oxide derivatives and thiazoloazole S,S-dioxide derivatives, and the addition salts thereof with an acid.

Composition according to Claim 14, characterized in that the indole derivatives are chosen from the compounds of formula below, and the addition salts thereof with an acid: x N R2 RR R in which: R, represents a hydrogen atom, a C 1 -C 4 alkyl radical, a C 2 -C 4 mono- or polyhydroxyalkyl radical or a aminoalkyl radical in which the amine is mono- or disubstituted with a C,-C 4 alkyl group; R 2 represents a hydrogen atom or a Ci-C 4 alkyl radical; R 3 represents a hydrogen atom or a C 1 -C 4 alkyl or hydroxyl radical; X represents a hydroxyl radical or a radical NHR 4 in which R 4 represents a hydrogen atom or a C 1 -C 4 alkyl or Ci-C 4 hydroxyalkyl radical.

16. Composition according to Claim characterized in that the indole derivatives are chosen from 4-hydroxyindole, 6-hydroxyindole, 7-aminoindole, 6-aminoindole, 7-hydroxyindole, 7-ethyl-6-(B-hydroxy- ethyl)aminoindole, 4-aminoindole, 6-hydroxy- 1-methylindole, 5,6-dihydroxyindole, 4-hydroxy- l-N-methylindole, 4-hydroxy-2-methylindole, 4-hydroxy- 4-hydroxy-l-N- (-hydroxyethyl)indole, 4-hydroxy-l-N- (-hydroxypropyl)indole, 1-N-(P,y-dihydroxypropyl)-4-hydroxyindole, 4-hydroxy- and 1-N-(y-dimethylaminopropyl)-4-hydroxyindole, and the addition salts thereof with an acid.

17. Composition according to Claim 14, characterized in that the indoline derivatives are chosen from 4-hydroxyindoline, 6-hydroxyindoline, 6-aminoindoline and 5,6-dihydroxyindoline, and the addition salts thereof with an acid.

18. Composition according to Claim 14, characterized in that the benzimidazole derivatives are chosen from the compounds of formula (II) below, and the addition salts thereof with an acid: R 7 R 8 N R6 R in which: ,R 5 represents a hydrogen atom or a Cl-C 4 alkyl radical, 1 41 R, represents a hydrogen atom or a Cl-C, alkyl or phenyl radical, R, represents a hydroxyl, amino or methoxy radical, R, represents a hydrogen atom or a hydroxyl, methoxy or C,-C 4 alkyl radical; with the proviso that: when R, denotes an amino radical, then it occupies position 4, when R, occupies position 4, then R, occupies position 7, when R, occupies position 5, then R 8 occupies position 6.

19. Composition according to Claim 18, characterized in that the benzimidazole derivatives are chosen from 4-hydroxybenzimidazole, 4-aminobenzimid- azole, 4-hydroxy-7-methylbenzimidazole, 4-hydroxy- 2-methylbenzimidazole, l-butyl-4-hydroxybenzimidazole, 4-amino-2-methylbenzimidazole, 5,6-dihydroxybenzimid- azole, 5-hydroxy-6-methoxybenzimidazole, 4,7-dihydroxybenzimidazole, 4,7-dihydroxy- l-methylbenzimidazole, 4,7-dimethoxybenzimidazole, 5,6-dihydroxy-l-methylbenzimidazole, 5,6-dihydroxy- 2-methylbenzimidazole and 5,6-dimethoxybenzimidazole, and the addition salts thereof with an acid.

20. Composition according to Claim 14, characterized in that the benzomorpholine derivatives 42 are chosen from the compounds of formula (III) below, and the addition salts thereof with an acid: 0 ya 11 1 Z 1 R9 in which: R 9 and R 10 which may be identical or different, represent a hydrogen atom or a C 1 -C 4 alkyl radical, Z represents a hydroxyl or amino radical.

21. Composition according to Claim characterized in that the benzomorpholine derivatives are chosen from 6-hydroxy-1,4-benzomorpholine, N-methyl-6-hydroxy-l,4-benzomorpholine and 6-amino- 1,4-benzomorpholine, and the addition salts thereof with an acid.

22. Composition according to Claim 14, characterized in that the sesamol derivatives are chosen from the compounds of formula (IV) below, and the addition salts thereof with an acid: i o (IV) 0 a-/ in which: Rj denotes a hydroxyl, amino, (C -C 4 )alkylamino, 43 monohydroxy alkylamino or polyhydroxy alkylamino radical, denotes a hydrogen or halogen atom or a C 1 -C 4 alkoxy radical.

23. Composition according to Claim 22, characterized in that the sesamol derivatives are chosen from 2-bromo-4, 2-methoxy-4, 5-methylenedioxyaniline and 2- (1-hydroxyethyl) amino-4, 5-methylenedioxybenzene, and the addition salts thereof with an acid.

24. Composition according to Claim 14, characterized in that the pyrazoloazole derivatives are chosen from: 2-methylpyrazolo[1,5-b] -1,2,4-triazole, 2-ethylpyrazolo[l,5-b] -1,2,4-triazole, 2-isopropylpyrazolo 11,5-b] -1,2,4-triazole, 2-phenylpyrazolo[l,5-b] -1,2,4-triazole, 2,6-dimethylpyrazolo[l,5-bI -1,2,4-triazole, 7-chloro-2,6-dimethylpyrazolo[l,5-b] -1,2,4-triazole, 3,6-dimethylpyrazolo[3,2-c]-1,2,4-triazole, 6-phenyl-3-methylthiopyrazolo[3,2-c] -1,2,4-triazole and 6-aminopyrazolo[Il, 5-a] benzimidazole, and the addition salts thereof with an acid.

25. Composition according to Claim 14, characterized in that the pyrroloazole derivatives are IC' 44 chosen from: 5-cyano-4-ethoxycarbonyl-8-methylpyrrolo 1,2,4 -triazole, 5-cyano-8-methyl-4-phenylpyrrolo[1,2-b] 1,2,4-triazole, 7-amido-6-ethoxycarbonylpyrrolo[1,2-aI -benzimidazole, and the addition salts thereof with an acid.

26. Composition according to Claim 14, characterized in that the imidazoloazole derivatives are chosen from: 7, 8-dicyanoimidazolo imidazole, 7,8-dicyano-4-methylimidazolol3,2-alimidazole, and the addition salts thereof with an acid.

27. Composition according to Claim 14, characterized in that the pyrazolopyrimidine derivatives are chosen from: pyrazolo[l, 5-a] pyrimidin-7-one, 2, 5-dimethylpyrazolo pyrimidin-7-one, 2-methyl-6-ethoxycarbonylpyrazolo pyrimidin- 7-one, 2-methyl-5-methoxymethylpyrazolo 5-a] pyrimidin- 7-one, 2-tert-butyl-5-trifluoromethylpyrazolo[1,5-a] pyrimidin-7-one, 2,7-dimethylpyrazolo[1,5-alpyrimidin-5-one, and the addition salts thereof with an acid. -J *i

28. Composition according to Claim 14, characterized in that the derivatives are chosen from: 1,2-diphenylpyrazoline-3,5-dione, 1,2-diethylpyrazoline-3,5-dione, and the addition salts thereof with an acid.

29. Composition according to any one of the preceding claims, characterized in that the heterocyclic coupler(s) represent(s) from 0.0001 to by weight relative to the total weight of the ready-to- use dye composition.

Composition according to Claim 29, characterized in that the heterocyclic coupler(s) represent(s) from 0.005 to 5% by weight relative to the total weight of the ready-to-use dye composition.

31. Composition according to any one of the preceding claims, characterized in that it contains at least one additional oxidation base chosen from para- phenylenediamines, bis(phenyl)alkylenediamines, ortho- phenylenediamines, para-aminophenols and ortho- aminophenols, and the addition salts thereof with an acid and/or at least one additional coupler chosen from meta-phenylenediamines, meta-aminophenols and meta- diphenols, and the addition salts thereof with an acid.

32. Composition according to any one of the preceding claims, characterized in that the addition salts with an acid are chosen from hydrochlorides, hydrobromides, sulphates, tartrates, lactates and acetates.

33. Composition according to any one of the preceding claims, characterized in that the medium which is suitable for dyeing consists of water or a mixture of water and at least one organic solvent.

34. Composition according to any one of the preceding claims, characterized in that it has a pH of between 5 and 11.

35. Composition according to any one of the preceding claims, characterized in that it contains at least one peroxidase. @0SO S *5*S 5 S *5

36. Process for dyeing keratin fibres, characterised in that at least one ready-to-use dye composition as defined in any one of the preceding claims is applied to the said fibres, for a period which is sufficient to develop the desired coloration. S 5*55 20

37. Process according to Claim 36, characterized in that it includes a preliminary step which consists in separately storing, on the one hand, 0 a composition comprising, in a medium which is suitable for dyeing, at least one heterocyclic oxidation base as defined in any one of Claims 1, 8 to 13 and 32 and/or at least one heterocyclic coupler as defined in any one of Claims 1, 14 to 30 and 32, and, on the other hand, a composition comprising, in a medium which is suitable for dyeing, at least one enzyme of 2-electron oxidoreductase type in the presence of at least one donor for the said enzyme, and then in mixing them together at the time of use, after which this mixture is applied to the keratin fibres.

38. A dyeing kit, when used to perform the process of claim 37, characterised in that the kit includes a first compartment comprising composition and a second compartment comprising composition Dated this 3rd day of January 2001 L'OREAL By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia o e o