The subject of the present invention is a process for dyeing and/or lightening keratin materials, and in particular human keratin fibres such the hair, comprising the application of a composition resulting from the mixing of a composition A comprising a (bi)carbonate and ammonium hydroxide, and of an oxidizing composition B comprising a fatty substance in a content of greater than or equal to 25% by weight, at least one of the compositions comprising an oxyalkylenated (OA), preferably oxyethylenated (OE), non-ionic surfactant comprising a number of oxyalkylenated units ranging from 1 to 9, an oxyalkylenated (OA), preferably oxyethylenated (OE), non-ionic surfactant comprising at least 10 oxyalkylene units and a neutral or acidic amino acid.

Among the methods for dyeing human keratin fibres such as the hair, mention may be made of oxidation or permanent dyeing which uses dyeing compositions containing oxidation dye precursors, generally known as oxidation bases. These oxidation bases are colourless or weakly coloured compounds which, when combined with oxidizing products, may give rise to coloured compounds via a process of oxidative condensation.

The processes usually used for dyeing and/or lightening human keratin fibres consist in using (in combination with the dyeing composition in the case of a dyeing process) an aqueous composition comprising at least one oxidizing agent, under alkaline pH conditions in the vast majority of cases. This oxidizing agent has the role of degrading the melanin of the hair, which, depending on the nature of the oxidizing agent present, leads to more or less pronounced lightening of the fibres.

It also has the role of activating the oxidation of the oxidation dye precursors and the formation of coloured species. The oxidizing agent generally used is hydrogen peroxide.

One of the difficulties arises from the fact that the dyeing and/or lightening process is performed under alkaline conditions and that the alkaline agent most commonly used is aqueous ammonia (or ammonium hydroxide). The use of aqueous ammonia is particularly advantageous in processes of this type. Specifically, it makes it possible to adjust the pH of the composition to an alkaline pH to enable activation of the oxidizing agent. In addition, this basifying agent causes swelling of the keratin fibre, with raising of the scales, which promotes the penetration of the oxidizing agent, and also of the oxidation dyes, into the fibre, and thus increases the efficiency of the dyeing and/or lightening reactions. However, this basifying agent is highly volatile, and this causes unpleasantness to the user on account of the strong and fairly unpleasant characteristic odour of ammonia that is given off during the process.

Furthermore, the amount of ammonia given off requires the use of higher contents than necessary in order to compensate for this loss. This is not without consequences for the user, who not only is inconvenienced by the odour, but may also be confronted with greater risks of intolerance, for instance irritation of the scalp, which is reflected especially by stinging.

It has been proposed to replace all or some of the aqueous ammonia with one or more other standard basifying agents, but the solutions proposed hitherto do not result in compositions that are as effective as those based on aqueous ammonia, especially since these basifying agents do not provide sufficient lightening or dyeing of the pigmented fibres in the presence of the oxidizing agent. In addition, use of basifying agents in the form of salts such as (bi)carbonates can destabilize the composition comprising them and/or lead to significant damage to the fibre.

In point of fact, oxidation dyeing must satisfy a certain number of requirements. Thus, it must be free of toxicological drawbacks, it must enable varied shades to be obtained which have good resistance to external attacking factors such as light, bad weather, washing, permanent waving, perspiration and rubbing.

The colourings must also be powerful and make it possible to cover grey hair and, finally, they must be as unselective as possible, i.e. make it possible to produce the smallest possible colour differences along the same keratin fibre, which generally comprises areas that are differently sensitized (i.e. damaged) from its end to its root.

The compositions obtained must also have good mixing and application properties, and in particular good rheological properties so as not to run down onto the face, the scalp or beyond the areas that it is proposed to dye, when they are applied.

Finally, the dyeing operations must, as far as is possible, respect the integrity of the keratin fibres and give said fibres the best possible cosmetic properties.

Many attempts have been made in the field of hair dyeing in order to improve the dyeing properties, for example with the aid of adjuvants. However, the choice of these adjuvants is difficult in so far as they must improve the dyeing properties of dyeing compositions without harming the other properties of these compositions. In particular, these adjuvants must not harm the stability of the compositions, the application properties of the dyeing operation or the cosmetic properties of the dyed fibres. The aim of the present invention is to obtain a novel process for dyeing and/or lightening of keratin fibres which does not have the drawbacks of the prior art.

More particularly, the aim of the present invention is to provide a dyeing process, in particular for the oxidation dyeing of keratin fibres, which is very effective in terms of colouration, in particular in terms of coverage of grey hair, of level of power or strength of colouration, of selectivity, and of quality of the uniformity of the dyeing, with stable alkaline and oxidizing compositions that are easy to mix and to apply, which limits the olfactory problems on application while at the same time detrimentally modifying the keratin fibres as little as possible.

Another object of the present invention is to provide a process for lightening keratin fibres which does not have the drawbacks of those used with the existing compositions, these drawbacks being caused by the presence of large amounts of aqueous ammonia, and which is at least as effective in terms of the lightening and the uniformity of this lightening.

In parallel with the lightening of the fibres, there is also a risk of damage to these fibres and of their cosmetic properties.

This aim is achieved with the present invention, a subject of which is a process for dyeing and/or lightening keratin materials, and in particular keratin fibres, more particularly the hair, comprising the application to the keratin materials of a dyeing and/or lightening composition obtained by mixing:

a) at least one composition A comprising

- at least one (bi)carbonate,

- ammonium hydroxide,

- optionally at least one colouring agent,

b) at least one composition B comprising

- at least one chemical oxidizing agent, preferably hydrogen peroxide, and

- at least one fatty substance, which is preferably liquid, in a content of greater than or equal to 25% by weight relative to the total weight of the composition B,

the composition A and/or the composition B comprising:

- at least one oxyalkylenated (OA), preferably oxyethylenated (OE), non-ionic surfactant comprising a number of OA units, preferably OE units, ranging from 1 to 9, - at least one oxyalkylenated (OA), preferably oxyethylenated (OE), non-ionic surfactant comprising at least 10 OA units, preferably OE units, and

- at least one neutral or acidic amino acid and/or a salt thereof.

According to the invention, the term "chemical oxidizing agent" is intended to mean an oxidizing agent other than atmospheric oxygen.

When the process in accordance with the invention is used for dyeing keratin fibres, good dyeing properties are obtained, especially strong, powerful, chromatic and sparingly selective colourings that allow good coverage of grey hair and that show good resistance to the various attacking factors to which the hair may be subjected, such as shampoo, light, sweat and permanent reshaping operations, without impairing the cosmetic properties of the keratin fibres.

When the process in accordance with the present invention is used for bleaching or lightening keratin materials, especially the skin or keratin fibres, it produces a good lightening effect on the keratin materials without damaging them or impairing their cosmetic properties.

In addition, this process makes it possible to obtain entirely satisfactory dyeing or lightening compositions while using a lower concentration of basifying agent such as aqueous ammonia or while allowing the replacement of this basifying agent, leading to the disappearance of the olfactory discomfort due to this compound.

A subject of the invention is also a composition for dyeing (C) and/or lightening keratin materials, in particular keratin fibres,

comprising, in a cosmetically acceptable medium:

- at least one (bi)carbonate,

- ammonium hydroxide,

- optionally at least one colouring agent,

- at least one fatty substance, which is preferably liquid, in a content of greater than or equal to 25% by weight relative to the total weight of the composition B,

- at least one oxyalkylenated (OA), preferably oxyethylenated (OE), non-ionic surfactant comprising a number of OA units, preferably OE units, ranging from 1 to 9,

at least one oxyalkylenated (OA), preferably oxyethylenated (OE), non- ionic surfactant comprising at least 10 OA units, preferably OE units, - at least one chemical oxidizing agent, preferably hydrogen peroxide, and

- at least one neutral or acidic amino acid and/or a salt thereof.

Another subject of the invention is the use of the composition described above for treating keratin materials, in particular keratin fibres, in particular for dyeing and/or lightening keratin materials, in particular keratin fibres.

In the text hereinbelow, unless otherwise indicated, the limits of the indicated ranges are included in the invention.

The term“at least one” is intended to mean“one or more”. a) Composition A

Alkaline agent

Ammonium hydroxide

The content of ammonium hydroxide in the composition according to the invention more particularly represents from 0.01% to 15% by weight, preferably from 0.1% to 10% by weight and more preferentially from 1 % to 10% by weight relative to the total weight of the composition A.

(Bi)carbonate

The term“(bi)carbonate” is intended to mean a carbonate or a bicarbonate.

The (bi)carbonate(s) is/are preferably chosen from:

- carbonate(s), preferably chosen from:

a) carbonates of alkali metals (Met2 ⁺ , CO ₃ ² ), of alkaline-earth metals (Met’ ²⁺ , CC>3 ² ) or of phosphonium (R"4P ⁺ )2,CC>3 ² with Met’ representing an alkaline- earth metal and Met representing an alkali metal, and R”, which may be identical or different, representing a hydrogen atom or an optionally substituted (Ci-C ₆ )alkyl group such as hydroxyethyl; and mixtures thereof;

- or bicarbonate(s), preferably chosen from:

b) the compounds having the formulae below:

> R' ⁺ , HCO ₃ with R' representing a hydrogen atom, an alkali metal, or a phosphonium group R ^M 4P ⁺ - where R", which may be identical or different, represent a hydrogen atom, an optionally substituted (C1- C ₆ )alkyl group such as hydroxyethyl and, when R' represents a hydrogen atom, the hydrogen carbonate is then called dihydrogen carbonate (CO2, H2O); and

> Met’ ²⁺ (HCC>3 ^" )2 with Met’ representing an alkaline-earth metal;

- and mixtures thereof.

More particularly, the (bi)carbonate(s) is/are chosen from alkali metal and alkaline-earth metal (bi)carbonates; preferentially alkali metal (bi)carbonates, ammonium (bi)carbonates, or mixtures thereof.

Preferably, they are chosen from (bi)carbonates of Na, K, Mg, Ca and mixtures thereof. Preferably, the b(i)carbonate(s) is/are chosen from Na (bi)carbonate and K (bi)carbonate, and mixtures thereof.

According to one preferred embodiment, the (bi)carbonate(s) is/are ammonium bicarbonate.

These bicarbonates may originate from a natural water, for example spring water from the Vichy basin or from La-Roche Posay or Badoit water (cf. for example, patent document FR 2 814 943). Mention may in particular be made of sodium bicarbonate or sodium hydrogen carbonate [144-55-8] = NaHCC>3, and calcium bicarbonate = Ca(HCC>3)2.

The (bi)carbonate(s) may be present in a content ranging from 0.1 % to 15% by weight, preferably from 0.5% to 10% by weight, better still from 1 % to 7% by weight relative to the total weight of the composition A.

According to one embodiment, the (bi)carbonate(s) are present in a content of greater than or equal to 2% by weight, better still greater than or equal to 4% by weight, even better still greater than or equal to 5% relative to the weight of the composition A.

Additional alkaline agent

The composition A of the process of the invention may comprise one or more additional alkaline agents distinct from the ammonium hydroxide and the (bi)carbonate.

The additional basifying agent(s) may be mineral or organic or hybrid.

The additional mineral basifying agent(s) are preferably chosen from sodium hydroxide and potassium hydroxide, and mixtures thereof.

The organic basifying agent(s) are preferably chosen from organic amines with a pK _b at 25°C of less than 12, preferably less than 10 and even more advantageously less than 6. It should be noted that it is the pK _b corresponding to the function of highest basicity. In addition, the organic amines do not comprise any alkyl or alkenyl fatty chain comprising more than ten carbon atoms.

The organic basifying agent(s) are chosen, for example, from alkanolamines, oxyethylenated and/or oxypropylenated ethylenediamines, basic amino acids and the compounds of formula (II) below:

in which formula (II) W is a divalent C1-C6 alkylene radical optionally substituted with one or more hydroxyl groups or a C1-C6 alkyl radical, and/or optionally interrupted with one or more heteroatoms such as O, or NR _U ; R _x , R _y , R _z , R _t and R _u , which may be identical or different, represent a hydrogen atom or a C1-C6 alkyl, C1-C6 hydroxyalkyl or C1-C6 aminoalkyl radical.

Examples of amines of formula (II) that may be mentioned include 1 ,3- diaminopropane, 1 ,3-diamino-2-propanol, spermine and spermidine.

The term“alkanolamine” is intended to mean an organic amine comprising a primary, secondary or tertiary amine function, and one or more linear or branched C-i-Cs alkyl groups bearing one or more hydroxyl radicals.

Organic amines chosen from alkanolamines such as monoalkanolamines, dialkanolamines or trialkanolamines, comprising one to three identical or different C1-C4 hydroxyalkyl radicals, are in particular suitable for implementing the invention.

Among the compounds of this type, mention may be made of monoethanolamine (MEA), diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, N-dimethylaminoethanolamine, 2-amino-2-methyl-1 -propanol, triisopropanolamine, 2- amino-2-methyl-1 ,3-propanediol, 3-amino-1 ,2-propanediol, 3-dimethylamino-1 ,2- propanediol and tris(hydroxymethylamino)methane.

The organic amine may also be chosen from organic amines of heterocyclic type. Mention may particularly be made of pyridine, piperidine, imidazole, triazole, tetrazole and benzimidazole

The organic amine may also be chosen from compounds including a guanidine function. As amines of this type that may be used in the present invention, mention may be made in particular of creatine, creatinine, 1 ,1-dimethylguanidine, 1 ,1- diethylguanidine, glycocyamine, metformin, agmatine, N-amidinoalanine, 3- guanidinopropionic acid, 4-guanidinobutyric acid and 2- ([amino(imino)methyl]amino)ethane-1 -sulfonic acid. Hybrid compounds that may be mentioned include the salts of the amines mentioned previously with acids such as carbonic acid or hydrochloric acid.

Monoethanolamine hydrochloride may in particular be used.

The additional organic basifying agent(s) may be chosen from basic amino acids. The term "basic amino acids" is intended to mean amino acids which have a pH, at ambient temperature, in water of greater than 7. Preferably, the basic amino acids comprise a number of amino groups that is greater than the number of acid groups.

The basic amino acid(s) may be chosen from arginine, lysine and L-asparagine, and/or salts thereof.

Preferably, the additional basifying agent(s) present in composition A of the invention are chosen from alkanolamines, preferably corresponding to those of formula (III). The composition A according to the invention may have a content of additional basifying agent(s) ranging from 0.01 % to 20% by weight, preferably from 0.1 % to 10% by weight relative to the weight of the composition A.

According to one particular embodiment, the composition A or the final composition C used in the process according to the invention does not contain additional basifying agent.

Dyeing agent

The composition A according to the invention may comprise at least one colouring agent chosen from oxidation dye precursors and direct dyes, and mixtures thereof, preferably chosen from oxidation dye precursors, in particular from oxidation bases.

The direct dye(s) may be chosen from the direct dyes conventionally used in direct dyeing. By way of example, these direct dyes are chosen from nitrobenzene dyes, azo direct dyes, methine direct dyes, quinone direct dyes, azine direct dyes, triarylmethane direct dyes, indoamine direct dyes and natural direct dyes. These direct dyes may be of non-ionic, anionic or cationic nature.

Among the benzene direct dyes, mention may be made of 1 ,4-diamino-2- nitrobenzene, 1 -amino-2-nitro-4-(P-hydroxyethylamino)benzene, 1 -amino-2-nitro-4- bis(P-hydroxyethyl)aminobenzene, 1 ,4-bis(P-hydroxyethylamino)-2-nitrobenzene, 1 -b- hydroxyethylamino-2-nitro-4-bis-(P-hydroxyethylamino)benzene , 1 -b- hydroxyethylamino-2-nitro-4-aminobenzene, 1 ^-hydroxyethylamino-2-nitro-4-(ethyl)$- hydroxyethyl)aminobenzene, 1 -amino-3-methyl-4^-hydroxyethylamino-6- nitrobenzene, 1 -amino-2-nitro-4^-hydroxyethylamino-5-chlorobenzene, 1 ,2-diamino-4- nitrobenzene, 1 -amino-2-p-hydroxyethylamino-5-nitrobenzene, 1 ,2-bis-(P- hydroxyethylamino)-4-nitrobenzene, 1 -amino-2-[tris(hydroxymethyl)methylamino]-5- nitrobenzene, 1 -hydroxy-2-amino-5-nitrobenzene, 1 -hydroxy-2-amino-4-nitrobenzene, 1 -hydroxy-3-nitro-4-aminobenzene, 1 -hydroxy-2-amino-4, 6-dinitrobenzene, 1 -b- hydroxyethyloxy-2-p-hydroxyethylamino-5-nitrobenzene, l -methoxy-2-b- hydroxyethylamino-5-nitrobenzene, 1 ^-hydroxyethyloxy-3-methylamino-4- nitrobenzene, 1 ^,Y-dihydroxypropyloxy-3-methylamino-4-nitrobenzene, 1 -b- hydroxyethylamino-4-b,g-dihydroxypropyloxy-2-nitrobenzene, 1 -b,g- dihydroxypropylamino-4-trifluoromethyl-2-nitrobenzene, 1 ^-hydroxyethylamino-4- trifluoromethyl-2-nitrobenzene, 1 ^-hydroxyethylamino-3-methyl-2-nitrobenzene, 1 -b- aminoethylamino-5-methoxy-2-nitrobenzene, 1 -hydroxy-2-chloro-6-ethylamino-4- nitrobenzene, 1 -hydroxy-2-chloro-6-amino-4-nitrobenzene, 1 -hydroxy-6-[bis-$- hydroxyethyl)amino]-3-nitrobenzene, 1 -b-hydroxyethylamino-2-nitrobenzene, 1 - hydroxy-4^-hydroxyethylamino-3-nitrobenzene.

Among the azo direct dyes, mention may be made of the cationic azo dyes described in patent applications WO 95/15144, WO 95/01772, EP 0 714 954, FR 2 822 696, FR 2 825 702, FR 2 825 625, FR 2 822 698, FR 2 822 693, FR 2 822 694, FR 2 829 926, FR 2 807 650, WO 02/078 660, WO 02/100 834, WO 02/100 369 and FR 2 844 269, the content of which forms an integral part of the invention.

Among these compounds, mention may be made most particularly of 1 ,3-dimethyl- 2-[[4-(dimethylamino)phenyl]azo]-1 H-imidazolium chloride, 1 ,3-dimethyl-2-[(4- aminophenyl)azo]-1 H-imidazolium chloride and 1 -methyl-4-

[(methylphenylhydrazono)methyl]pyridinium methyl sulfate.

Among the azo direct dyes, mention may also be made of the following dyes, described in the Colour Index International 3rd edition: Disperse Red 17, Acid Yellow 9, Acid Black 1 , Basic Red 22, Basic Red 76, Basic Yellow 57, Basic Brown 16, Acid Yellow 36, Acid Orange 7, Acid Red 33, Acid Red 35, Basic Brown 17, Acid Yellow 23, Acid Orange 24, Disperse Black 9.

Mention may also be made of 1 -(4’-aminodiphenylazo)-2-methyl-4-bis^- hydroxyethyl)aminobenzene and 4-hydroxy-3-(2-methoxyphenylazo)-1 - naphthalenesulfonic acid.

Among the quinone direct dyes, mention may be made of the following dyes: Disperse Red 15, Solvent Violet 13, Acid Violet 43, Disperse Violet 1 , Disperse Violet 4, Disperse Blue 1 , Disperse Violet 8, Disperse Blue 3, Disperse Red 1 1 , Acid Blue 62, Disperse Blue 7, Basic Blue 22, Disperse Violet 15, Basic Blue 99, and also the following compounds: 1 -N-methylmorpholiniumpropylamino-4-hydroxyanthraquinone, 1 - aminopropylamino-4-methylaminoanthraquinone, 1 -aminopropylaminoanthraquinone, 5-3-hydroxyethyl-1 ,4-diaminoanthraquinone, 2-aminoethylaminoanthraquinone, 1 ,4- bis(3,y-dihydroxypropylamino)anthraquinone.

Among the azine dyes, mention may be made of the following compounds: Basic Blue 17, Basic Red 2.

Among the triarylmethane dyes, mention may be made of the following compounds: Basic Green 1 , Acid Blue 9, Basic Violet 3, Basic Violet 14, Basic Blue 7, Acid Violet 49, Basic Blue 26, Acid Blue 7.

Among the indoamine dyes, mention may be made of the following compounds: 2-3-hydroxyethylamino-5-[bis(3-4’-hydroxyethyl)amino]anili no-1 ,4-benzoquinone, 2-b- hydroxyethylamino-5-(2’-methoxy-4’-amino)anilino-1 ,4-benzoquinone, 3-N-(2’-chloro- 4’-hydroxy)phenylacetylamino-6-methoxy-1 ,4-benzoquinoneimine, 3-N-(3’-chloro-4’- methylamino)phenylureido-6-methyl-1 ,4-benzoquinoneimine and 3-[4’-N-

(ethylcarbamylmethyl)amino]phenylureido-6-methyl-1 ,4-benzoquinoneimine.

Among the natural direct dyes that may be used according to the invention, mention may be made of lawsone, juglone, alizarin, purpurin, carminic acid, kermesic acid, purpurogallin, protocatechaldehyde, indigo, isatin, curcumin, spinulosin, apigenidin and orceins. Use may also be made of extracts or decoctions comprising these natural dyes and in particular henna-based poultices or extracts.

The direct dye(s) are generally present in the composition A in an amount of between 0.001 % and 20% by weight approximately and even more preferentially between 0.005% and 10% by weight approximately relative to the total weight of the composition.

The oxidation dye(s) may be chosen from the oxidation bases and couplers conventionally used in the field of dyeing.

Examples of oxidation bases that may be mentioned include para- phenylenediamines, double bases, para-aminophenols, ortho-aminophenols and heterocyclic bases, and the addition salts thereof.

Among the para-phenylenediamines, mention may be made, by way of example, of para-phenylenediamine, para-toluenediamine, 2-chloro-para-phenylenediamine, 2,3- dimethyl-para-phenylenediamine, 2,6-dimethyl-para-phenylenediamine, 2,6-diethyl- para-phenylenediamine, 2,5-dimethyl-para-phenylenediamine, N,N-dimethyl-para- phenylenediamine, N,N-diethyl-para-phenylenediamine, N,N-dipropyl-para- phenylenediamine, 4-amino-N,N-diethyl-3-methylaniline, N,N-bis(p-hydroxyethyl)-para- phenylenediamine, 4-N,N-bis(p-hydroxyethyl)amino-2-methylaniline, 4-N,N-bis(p- hydroxyethyl)amino-2-chloroaniline, 2-p-hydroxyethyl-para-phenylenediamine, 2-fluoro- para-phenylenediamine, 2-isopropyl-para-phenylenediamine, N-(p-hydroxypropyl)- para-phenylenediamine, 2-hydroxymethyl-para-phenylenediamine, N,N-dimethyl-3- methyl-para-phenylenediamine, N-ethyl-N-(p-hydroxyethyl)-para-phenylenediamine, N- (P,y-dihydroxypropyl)-para-phenylenediamine, N-(4’-aminophenyl)-para- phenylenediamine, N-phenyl-para-phenylenediamine, 2-p-hydroxyethyloxy-para- phenylenediamine, 2-p-acetylaminoethyloxy-para-phenylenediamine, N-(b- methoxyethyl)-para-phenylenediamine, 4-aminophenylpyrrolidine, 2-thienyl-para- phenylenediamine, 2-p-hydroxyethylamino-5-aminotoluene and 3-hydroxy-1-(4’- aminophenyl)pyrrolidine, and the addition salts thereof with an acid.

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

Among the double bases, examples that may be mentioned include bis(phenyl)alkylenediamines and bis-para-aminophenols.

Among the bis(phenyl)alkylenediamines, examples that may be mentioned include N,N’-bis(p-hydroxyethyl)-N,N’-bis(4’-aminophenyl)-1 ,3-diaminopropanol, N,N’-bis(p- hydroxyethyl)-N,N’-bis(4’-aminophenyl)ethylenediamine, N,N’-bis(4- aminophenyl)tetramethylenediamine, N,N’-bis(p-hydroxyethyl)-N,N’-bis(4- aminophenyl)tetramethylenediamine, N,N’-bis(4- methylaminophenyl)tetramethylenediamine, N,N’-bis(ethyl)-N,N’-bis(4’-amino-3’- methylphenyl)ethylenediamine and 1 ,8-bis(2,5-diaminophenoxy)-3,6-dioxaoctane, and addition salts thereof with an acid.

Among the para-aminophenols that may be mentioned, for example, are para- aminophenol, 4-amino-3-methylphenol, 4-amino-3-fluorophenol, 4-amino-3- hydroxymethylphenol, 4-amino-2-methylphenol, 4-amino-2-hydroxymethylphenol, 4- amino-2-methoxymethylphenol, 4-amino-2-aminomethylphenol, 4-amino-2-(p- hydroxyethylaminomethyl)phenol and 4-amino-2-fluorophenol, and the addition salts thereof with an acid. Among the ortho-aminophenols, examples that may be mentioned include 2- aminophenol, 2-amino-5-methylphenol, 2-amino-6-methylphenol and 5-acetamido-2- aminophenol, and the addition salts thereof with an acid.

Among the heterocyclic bases, examples that may be mentioned include pyridine derivatives, pyrimidine derivatives and pyrazole derivatives.

Among the pyridine derivatives, mention may be made of the compounds described, for example, in patents GB 1 026 978 and GB 1 153 196, for instance 2,5- diaminopyridine, 2-(4-methoxyphenyl)amino-3-aminopyridine, 2,3-diamino-6- methoxypyridine, 2-(p-methoxyethyl)amino-3-amino-6-methoxypyridine and 3,4- diaminopyridine, and the addition salts thereof with an acid.

Other pyridine oxidation bases that are useful in the present invention are the 3- aminopyrazolo[1 ,5-a]pyridine oxidation bases or addition salts thereof described, for example, in patent application FR 2 801 308. Examples that may be mentioned include pyrazolo[1 ,5-a]pyrid-3-ylamine, 2-acetylaminopyrazolo[1 ,5-a]pyrid-3-ylamine, 2- (morpholin-4-yl)pyrazolo[1 ,5-a]pyrid-3-ylamine, 3-aminopyrazolo[1 ,5-a]pyridine-2- carboxylic acid, 2-methoxypyrazolo[1 ,5-a]pyrid-3-ylamine, (3-aminopyrazolo[1 ,5- a]pyrid-7-yl)methanol, 2-(3-aminopyrazolo[1 ,5-a]pyrid-5-yl)ethanol, 2-(3- aminopyrazolo[1 ,5-a]pyrid-7-yl)ethanol, (3-aminopyrazolo[1 ,5-a]pyrid-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]pyrid-3-ylamine, pyrazolo[1 ,5- a]pyridine-3, 5-diamine, 5-(morpholin-4-yl)pyrazolo[1 ,5-a]pyrid-3-ylamine, 2-[(3- aminopyrazolo[1 ,5-a]pyrid-5-yl)(2-hydroxyethyl)amino]ethanol, 2-[(3- aminopyrazolo[1 ,5-a]pyrid-7-yl)(2-hydroxyethyl)amino]ethanol, 3-aminopyrazolo[1 ,5- a]pyridin-5-ol, 3-aminopyrazolo[1 ,5-a]pyridin-4-ol, 3-aminopyrazolo[1 ,5-a]pyridin-6-ol, 3-aminopyrazolo[1 ,5-a]pyridin-7-ol and 2-[(3-aminopyrazolo[1 ,5-a]pyridin-2- yl)oxy]ethanol, and the addition salts thereof with an acid or with a base.

Among the pyrimidine derivatives, mention may be made of the compounds described, for example, in patents DE 2 359 399; JP 88-169 571 ; JP 05-63124; EP 0 770 375 or patent application WO 96/15765, for instance 2, 4,5,6- tetraaminopyrimidine, 4-hydroxy-2,5,6-triaminopyrimidine, 2-hydroxy-4,5,6- triaminopyrimidine, 2,4-dihydroxy-5,6-diaminopyrimidine and 2,5,6-triaminopyrimidine, and pyrazolopyrimidine derivatives such as those mentioned in patent application FR- A-2 750 048, and among which mention may be made of 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-aminopyrazolo[1 ,5- a]pyrimidin-7-ylamino)ethanol, 2-(7-aminopyrazolo[1 ,5-a]pyrimidin-3-ylamino)ethanol,

2-[(3-aminopyrazolo[1 ,5-a]pyrimidin-7-yl)(2-hydroxyethyl)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 and 3-amino- 5-methyl-7-imidazolylpropylaminopyrazolo[1 ,5-a]pyrimidine, and the addition salts thereof with an acid, and the tautomeric forms thereof, when a tautomeric equilibrium exists.

Among the pyrazole derivatives that may be mentioned are the compounds described in patents DE 3 843 892 and DE 4 133 957, and patent applications WO 94/08969, WO 94/08970, FR-A-2 733 749 and DE 195 43 988, for instance 4,5- diamino-1 -methylpyrazole, 4,5-diamino-1 -(p-hydroxyethyl)pyrazole, 3,4- diaminopyrazole, 4,5-diamino-1 -(4’-chlorobenzyl)pyrazole, 4,5-diamino-1 ,3- dimethylpyrazole, 4,5-diamino-3-methyl-1 -phenylpyrazole, 4,5-diamino-1 -methyl-3- phenylpyrazole, 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-1 -tert-butyl-3- methylpyrazole, 4,5-diamino-1 -(p-hydroxyethyl)-3-methylpyrazole, 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-1 -methylpyrazole, 4,5- diamino-3-hydroxymethyl-1 -isopropylpyrazole, 4,5-diamino-3-methyl-1 - isopropylpyrazole, 4-amino-5-(2’-aminoethyl)amino-1 ,3-dimethylpyrazole, 3,4,5- triaminopyrazole, 1 -methyl-3, 4, 5-triaminopyrazole, 3,5-diamino-1 -methyl-4- methylaminopyrazole and 3, 5-diamino-4-(p-hydroxyethyl)amino-1 -methylpyrazole, and the addition salts thereof with an acid.

Pyrazole derivatives that may also be mentioned include diamino-N,N- dihydropyrazolopyrazolones and especially those described in patent application FR 2 886 136, such as the following compounds and the addition salts thereof.

Among these compounds, the following are preferred:

2,3-diamino-6,7-dihydro-1 H,5H-pyrazolo[1 ,2-a]pyrazol-1 -one,

2-amino-3-ethylamino-6,7-dihydro-1 H,5H-pyrazolo[1 ,2-a]pyrazol-1 -one,

2-amino-3-isopropylamino-6,7-dihydro-1 H,5H-pyrazolo[1 ,2-a]pyrazol-1 -one,

2-amino-3-(pyrrolidin-1 -yl)-6,7-dihydro-1 H,5H-pyrazolo[1 ,2-a]pyrazol-1 -one,

4.5-diamino-1 ,2-dimethyl-1 ,2-dihydropyrazol-3-one,

4.5-diamino-1 ,2-diethyl-1 ,2-dihydropyrazol-3-one,

4.5-diamino-1 ,2-di(2-hydroxyethyl)-1 ,2-dihydropyrazol-3-one, 2-amino-3-(2-hydroxyethyl)amino-6,7-dihydro-1 H,5H-pyrazolo[1 ,2-a]pyrazol-1-one, 2-amino-3-dimethylamino-6,7-dihydro-1 H,5H-pyrazolo[1 ,2-a]pyrazol-1-one,

2.3-diamino-5,6,7,8-tetrahydro-1 H,6H-pyridazino[1 ,2-a]pyrazol-1-one,

4-amino-1 ,2-diethyl-5-(pyrrolidin-1 -yl)-1 ,2-dihydropyrazol-3-one,

4-amino-5-(3-dimethylaminopyrrolidin-1 -yl)-1 ,2-diethyl-1 ,2-dihydropyrazol-3-one,

2.3-diamino-6-hydroxy-6,7-dihydro-1 H,5H-pyrazolo[1 ,2-a]pyrazol-1-one.

Heterocyclic bases that will preferentially be used include 4,5-diamino-1-(3- hydroxyethyl)pyrazole, 2,3-diamino-6,7-dihydro-1 H,5H-pyrazolo[1 ,2-a]pyrazol-1-one and 2-[(3-aminopyrazolo[1 ,5-a]pyridin-2-yl)oxy]ethanol and/or the addition salts or solvates thereof.

The oxidation base(s) are generally present in the dyeing composition A in an amount of between 0.001 % and 10% by weight approximately and preferably between 0.005% and 6% by weight approximately relative to the total weight of the composition.

Examples of couplers that may be mentioned include meta-phenylenediamines, meta-aminophenols, meta-diphenols, naphthalene-based couplers and heterocyclic couplers, and the addition salts thereof.

Mention may be made especially of 2-methyl-5-aminophenol, 5-N-(b- hydroxyethyl)amino-2-methylphenol, 6-chloro-2-methyl-5-aminophenol, 3-aminophenol,

1.3-dihydroxybenzene, 1 ,3-dihydroxy-2-methylbenzene, 4-chloro-1 ,3- dihydroxybenzene, 2,4-diamino-1 -(3-hydroxyethyloxy)benzene, 2-amino-4-(3- hydroxyethylamino)-1 -methoxybenzene, 1 ,3-diaminobenzene, 1 ,3-bis(2,4- diaminophenoxy)propane, 3-ureidoaniline, 3-ureido-1 -dimethylaminobenzene, sesamol, 1-3-hydroxyethylamino-3,4-methylenedioxybenzene, a-naphthol, 2-methyl-1- naphthol, 6-hydroxyindole, 4-hydroxyindole, 4-hydroxy-N-methylindole, 2-amino-3- hydroxypyridine, 6-hydroxybenzomorpholine, 3,5-diamino-2,6-dimethoxypyridine, 1-N- (3-hydroxyethyl)amino-3,4-methylenedioxybenzene and 2,6-bis(3- hydroxyethylamino)toluene, and the addition salts thereof with an acid.

The coupler(s) are generally present in the composition A in an amount of between 0.001 % and 10% by weight approximately and preferably between 0.005% and 6% by weight approximately relative to the total weight of the composition.

In general, the addition salts of the oxidation bases and couplers that may be used in the context of the invention are especially chosen from the addition salts with an acid, such as the hydrochlorides, hydrobromides, sulfates, citrates, succinates, tartrates, lactates, tosylates, benzenesulfonates, phosphates and acetates, and the addition salts with a base, such as sodium hydroxide, potassium hydroxide, aqueous ammonia, amines or alkanolamines. b) Oxidizing composition B

Fatty substance

The composition B of the process according to the invention comprises one or more fatty substances, preferably liquid(s) (or oil).

The term "fatty substance" is intended to mean an organic compound that is insoluble in water at ordinary temperature (25°C) and at atmospheric pressure (760 mmHg) (solubility of less than 5%, preferably less than 1 % and even more preferentially less than 0.1 %). They have in their structure at least one hydrocarbon-based chain comprising at least 6 carbon atoms or a sequence of at least two siloxane groups. In addition, the fatty substances are generally soluble in organic solvents under the same temperature and pressure conditions, for instance chloroform, ethanol, benzene, liquid petroleum jelly or decamethylcyclopentasiloxane.

The term "o/T is intended to mean a "fatty substance" that is liquid at ambient temperature (25°C) and at atmospheric pressure (760 mmHg or 1.013x10 ⁵ Pa).

The term "non-silicone o/T is intended to mean an oil not containing any silicon (Si) atoms and the term "silicone o/ is intended to mean an oil containing at least one silicon atom.

More particularly, the fatty substances are chosen from C6-C16 hydrocarbons, hydrocarbons comprising more than 16 carbon atoms, non-silicone oils of animal origin, triglycerides of plant or synthetic origin, fluoro oils, fatty alcohols, non-salified fatty acids, esters of fatty acid and/or of fatty alcohol other than triglycerides, non-silicone waxes other than solid fatty alcohols and than solid synthetic esters, and silicones, and mixtures thereof.

It is recalled that, for the purposes of the invention, fatty alcohols, esters and acids more particularly bear at least one linear or branched, saturated or unsaturated hydrocarbon- based group comprising 6 to 30 carbon atoms, which is optionally substituted, in particular with one or more hydroxyl groups (in particular 1 to 4). If they are unsaturated, these compounds may comprise one to three conjugated or unconjugated carbon- carbon double bonds.

The linear or branched hydrocarbons of mineral or synthetic origin, comprising more than 16 carbon atoms, are preferably chosen from liquid paraffins, liquid petroleum jelly, polydecenes and hydrogenated polyisobutene such as Parleam®, and mixtures thereof. As regards the C6-C16 lower alkanes, they are linear or branched, or possibly cyclic.

Examples that may be mentioned include hexane, cyclohexane, undecane, dodecane, tridecane or isoparaffins, such as isohexadecane, isodecane or isododecane, and mixtures thereof.

A hydrocarbon-based oil of animal origin that may be mentioned is perhydrosqualene.

The triglycerides of plant or synthetic origin are preferably chosen from liquid fatty acid triglycerides comprising from 6 to 30 carbon atoms, for instance heptanoic or octanoic acid triglycerides, or, alternatively, more particularly from those present in plant oils, for instance sunflower oil, corn oil, soybean oil, marrow oil, grapeseed oil, sesame seed oil, hazelnut oil, apricot oil, macadamia oil, arara oil, sunflower oil, castor oil, avocado oil, jojoba oil, shea butter oil or synthetic caprylic/capric acid triglycerides, for instance those sold by the company Stearineries Dubois or those sold under the names Miglyol® 810, 812 and 818 by the company Dynamit Nobel, and mixtures thereof.

The fluoro oils may be chosen from perfluoromethylcyclopentane and perfluoro-1 ,3- dimethylcyclohexane, sold under the names Flutec® PC1 and Flutec® PC3 by the company BNFL Fluorochemicals; perfluoro-1 ,2-dimethylcyclobutane; perfluoroalkanes such as dodecafluoropentane and tetradecafluorohexane, sold under the names PF 5050® and PF 5060® by the company 3M, or alternatively bromoperfluorooctyl sold under the name Foralkyl® by the company Atochem; nonafluoromethoxybutane and nonafluoroethoxyisobutane; perfluoromorpholine derivatives such as 4-trifluoromethyl perfluoromorpholine sold under the name PF 5052® by the company 3M.

The fatty alcohols that are suitable for use in the invention are more particularly chosen from linear or branched, saturated or unsaturated alcohols comprising from 8 to 30 carbon atoms. Examples that may be mentioned include cetyl alcohol, stearyl alcohol and a mixture thereof (cetylstearyl alcohol), octyldodecanol, 2-butyloctanol, 2- hexyldecanol, 2-undecylpentadecanol, oleyl alcohol, linolenyl alcohol, ricinoleyl alcohol, undecylenyl alcohol and linoleyl alcohol, and mixtures thereof.

The fatty acids that may be used in the context of the invention are more particularly chosen from saturated or unsaturated carboxylic acids comprising from 6 to 30 carbon atoms and in particular from 9 to 30 carbon atoms. They are advantageously chosen from myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid, linoleic acid, linolenic acid and isostearic acid. These fatty acids are, in the composition of the invention, not salified with organic or mineral bases, so as not to give rise to soaps.

As regards the esters of fatty acids and/or of fatty alcohols other than the triglycerides mentioned above and plant waxes, mention may especially be made of esters of saturated or unsaturated, linear C1-C26 or branched C3-C26 aliphatic monoacids or polyacids and of saturated or unsaturated, linear C1-C26 or branched C3-C26 aliphatic monoalcohols or polyalcohols, the total carbon number of the esters being greater than or equal to 6 and more advantageously greater than or equal to 10.

Among the monoesters, mention may be made of dihydroabietyl behenate; octyldodecyl behenate; isocetyl behenate; cetyl lactate; C12-C15 alkyl lactate; isostearyl lactate; lauryl lactate; linoleyl lactate; oleyl lactate; (iso)stearyl octanoate; isocetyl octanoate; octyl octanoate; cetyl octanoate; decyl oleate; isocetyl isostearate; isocetyl laurate; isocetyl stearate; isodecyl octanoate; isodecyl oleate; isononyl isononanoate; isostearyl palmitate; methylacetyl ricinoleate; myristyl stearate; octyl isononanoate; 2-ethylhexyl isononanoate; octyl palmitate; octyl pelargonate; octyl stearate; octyldodecyl erucate; oleyl erucate; ethyl and isopropyl palmitates, 2-ethylhexyl palmitate, 2-octyldecyl palmitate, alkyl myristates such as isopropyl, butyl, cetyl, 2-octyldodecyl, myristyl or stearyl myristate, hexyl stearate, butyl stearate, isobutyl stearate; dioctyl malate, hexyl laurate, 2-hexyldecyl laurate and mixtures thereof.

Still within the context of this variant, esters of C4-C22 dicarboxylic or tricarboxylic acids and of C1-C22 alcohols and esters of mono-, di- or tricarboxylic acids and of C2-C26 di-, tri-, tetra- or pentahydroxy alcohols may also be used.

Mention may especially be made of: diethyl sebacate; diisopropyl sebacate; diisopropyl adipate; di-n-propyl adipate; dioctyl adipate; diisostearyl adipate; dioctyl maleate; glyceryl undecylenate; octyldodecyl stearoyl stearate; pentaerythrityl monoricinoleate; pentaerythrityl tetraisononanoate; pentaerythrityl tetrapelargonate; pentaerythrityl tetraisostearate; pentaerythrityl tetraoctanoate; propylene glycol dicaprylate; propylene glycol dicaprate; tridecyl erucate; triisopropyl citrate; triisostearyl citrate; glyceryl trilactate; glyceryl trioctanoate; trioctyldodecyl citrate; trioleyl citrate; propylene glycol dioctanoate; neopentyl glycol diheptanoate; diethylene glycol diisononanoate; and polyethylene glycol distearates, and mixtures thereof. Among the esters mentioned above, it is preferred to use ethyl, isopropyl, myristyl, cetyl or stearyl palmitate, 2-ethylhexyl palmitate, 2-octyldecyl palmitate, alkyl myristates such as isopropyl, butyl, cetyl or 2-octyldodecyl myristate, hexyl stearate, butyl stearate, isobutyl stearate; dioctyl malate, hexyl laurate, 2-hexyldecyl laurate, isononyl isononanoate and cetyl octanoate, and mixtures thereof.

The composition may also comprise, as fatty ester, sugar esters and diesters of C6-C30 and preferably C12-C22 fatty acids. It is recalled that the term "sugar" is intended to mean oxygen-bearing hydrocarbon-based compounds bearing several alcohol functions, with or without aldehyde or ketone functions, and which comprise at least 4 carbon atoms. These sugars may be monosaccharides, oligosaccharides or polysaccharides.

Examples of suitable sugars that may be mentioned include sucrose, glucose, galactose, ribose, fucose, maltose, fructose, mannose, arabinose, xylose and lactose, and derivatives thereof, especially alkyl derivatives, such as methyl derivatives, for instance methylglucose.

The esters of sugar and of fatty acids may especially be chosen from the group comprising the esters or mixtures of esters of sugars described previously and of linear or branched, saturated or unsaturated C6-C30, preferably C12-C22, fatty acids. If they are unsaturated, these compounds may comprise one to three conjugated or unconjugated carbon-carbon double bonds.

The esters according to this variant may also be chosen from mono-, di-, tri- and tetraesters, polyesters, and mixtures thereof.

These esters may be, for example, oleates, laurates, palmitates, myristates, behenates, cocoates, stearates, linoleates, linolenates, caprates and arachidonates, or mixtures thereof such as, in particular, oleopalmitate, oleostearate and palmitostearate mixed esters.

More particularly, use is made of monoesters and diesters and especially sucrose, glucose or methylglucose monooleate or dioleate, stearate, behenate, oleopalmitate, linoleate, linolenate or oleostearate.

An example that may be mentioned is the product sold under the name Glucate® DO by Amerchol, which is a methylglucose dioleate.

Examples of esters or mixtures of esters of sugar and of fatty acid that may also be mentioned include:

- the products sold under the names F160, F140, F110, F90, F70 and SL40 by the company Crodesta, respectively denoting sucrose palmitostearates formed from 73% monoester and 27% diester and triester, from 61% monoester and 39% diester, triester and tetraester, from 52% monoester and 48% diester, triester and tetraester, from 45% monoester and 55% diester, triester and tetraester, from 39% monoester and 61% diester, triester and tetraester, and sucrose monolaurate;

- the products sold under the name Ryoto Sugar Esters, for example referenced B370 and corresponding to sucrose behenate formed from 20% monoester and 80% diester, triester and polyester;

- the sucrose mono-dipalmito-stearate sold by the company Goldschmidt under the name Tegosoft® PSE.

The non-silicone wax(es) other than solid fatty alcohols and solid synthetic esters are chosen especially from carnauba wax, candelilla wax, esparto wax, paraffin wax, ozokerite, plant waxes, such as olive tree wax, rice wax, hydrogenated jojoba wax or absolute flower waxes, such as the blackcurrant blossom essential wax sold by the company Bertin (France), or animal waxes, such as beeswaxes or modified beeswaxes (cerabellina); other waxes or waxy raw materials that may be used according to the invention are especially marine waxes, such as the wax sold by the company Sophim under the reference M82, polyethylene waxes or polyolefin waxes in general.

The fatty substance(s) do not comprise any C2-C3 oxyalkylene units. Preferably, they do not contain any glycerol units. More particularly, the fatty substances are other than fatty acids.

More particularly, the fatty substances are chosen from compounds that are liquid or pasty at ambient temperature and at atmospheric pressure.

Preferably, the fatty substance is a compound that is liquid at a temperature of 25°C and at atmospheric pressure, or oil.

According to one preferred variant, the fatty substances are not silicone-based.

The fatty substances are preferably chosen from C6-C16 hydrocarbons, hydrocarbons comprising more than 16 carbon atoms, non-silicone oils of animal origin, triglycerides of plant or synthetic origin, fatty alcohols, fatty acid and/or fatty alcohol esters, or mixtures thereof.

Preferably, the fatty substance is chosen from linear or branched hydrocarbons, of mineral or synthetic origin, comprising more than 16 carbon atoms, or mixtures thereof, for instance liquid petroleum jelly. The composition B used in the process of the invention has a content of fatty substance, which is preferably liquid, of greater than or equal to 25% by weight of the total weight of the composition, preferably greater than or equal to 30% by weight, better still greater than or equal to 40% by weight and even more preferentially greater than or equal to 45% by weight, better still greater than or equal to 50% by weight.

The fatty substance(s) generally represent from 25% to 80% by weight, preferably from 30% to 70%, even more preferentially from 40% to 65% and better still from 45% to 60% by weight relative to the total weight of the composition B.

Chemical oxidizing agent

The composition B comprises one or more chemical oxidizing agents. The term "chemical oxidizing agent" is intended to mean an oxidizing agent other than atmospheric oxygen.

More particularly, the chemical oxidizing agent(s) are chosen from hydrogen peroxide, urea peroxide, alkali metal bromates, peroxygenated salts, for instance persulfates or perborates, peracids and precursors thereof, and alkali metal or alkaline- earth metal percarbonates.

The oxidizing agent is advantageously hydrogen peroxide .

The concentration of chemical oxidizing agents may range more particularly from 0.1 % to 50% by weight, even more preferentially from 3% to 20% by weight and better still from 5% to 15% by weight relative to the weight of the composition B.

According to one particular embodiment, the composition B in accordance with the invention comprises no oxidation dye precursor or persalt.

According to one particular embodiment, the composition B in accordance with the invention comprises no colouring agent or persalt.

Neutral or acidic amino acid

The composition A and/or the oxidizing composition B that are used in the process according to the invention comprise one or more neutral or acidic amino acids.

The term "neutral amino acids" is intended to mean amino acids which have a pH, at ambient temperature (25°C), in water of between 5 and 7 inclusive. The term "acidic amino acids" is intended to mean amino acids which have a pH, at ambient temperature, in water of less than 5.

Preferably, the neutral or acidic amino acids of the invention comprise a number of amino groups that is less than or equal to the number of acid groups.

The neutral or acidic amino acid may be chosen from the amino acids of formulae (I) and (II) below, and also the betaine forms thereof, the optical isomers thereof, the solvates thereof such as hydrates, and the organic or mineral acid or base salts thereof:

(I) (II)

in which formulae (I) and (II):

- R represents a hydrogen atom, or a linear or branched, preferably linear, C1-C5 alkyl group, optionally interrupted with one or more heteroatoms such as O, S or N, said alkyl group being optionally substituted with at least one group chosen from hydroxyl, amino, -SH, -C(0)-0H, -S(0) ₂ -0H, -C(0)-0-, M ⁺ , and -S(0) ₂ -0-, M ⁺ , with M ⁺ representing a cationic counterion such as an alkali metal, alkaline-earth metal, or ammonium,

- n is 0 or 1 .

The salt(s) of the neutral or acidic amino acids may be chosen from the alkali or alkaline- earth metal salts or the ammonium salts.

The neutral or acidic amino acid(s) may be chosen from alanine, glycine, isoleucine, Leucine, serine, threonine, cysteine and methionine. Mention may also be made of proline, valine, N-phenylalanine, tryptophan and tyrosine, and/or the salts thereof. Preferably, the neutral or acidic amino acid(s) are chosen from the compounds of formula (I) and/or the salts thereof, more preferentially from alanine, glycine, isoleucine, leucine, serine, threonine, cysteine and methionine, and/or the salts thereof, and even more preferably from cysteine and methionine, and mixtures thereof.

The total amount of neutral or acidic amino acids in the composition A and/or B can range from 0.05% to 15% by weight relative to the total weight of each composition A and/or B, preferably from 0.1 % to 15%, better from 0.2% to 10% by weight, better still from 0.3 to 7% by weight, still preferably from 0.5% to 5% by weight of each composition A and/or B.

Preferably, composition A or B comprises from 0.7 to 4% by weight relative to the total weight of each composition A or B, and still preferably, composition A comprises from 0.7 to 4% by weight relative to the total weight of composition A.

The total amount of neutral or acidic amino acids in the composition resulting from the mixing of the compositions A and B can range from 0.01 % to 10% by weight relative to the total weight of each composition A and/or B, preferably from 0.1 % to 5% by weight, better still from 0.2% to 2% by weight.

Oxyalkylenated surfactants

The composition A and/or the oxidizing composition B that are used in the process according to the invention comprise at least one oxyalkylenated (OA) non-ionic surfactant comprising a number of OA units ranging from 1 to 9, said OA units preferably being oxyethylene units (OE), and at least one oxyalkylenated (OA) non-ionic surfactant comprising at least 10 OA units, said OA units preferably being oxyethylene (OE) units. According to one embodiment, the composition A and the composition B each comprise at least one oxyalkylenated (OA) non-ionic surfactant comprising a number of OA units, preferably OE units, ranging from 1 to 9, and at least one oxyalkylenated (OA) non-ionic surfactant comprising at least 10 OA units, preferably OE units.

Preferably, the oxyalkylenated non-ionic surfactants according to the invention are chosen from oxyethylenated non-ionic surfactants.

The oxyethylenated non-ionic surfactants comprising a number of OE units ranging from 1 to 9 and the oxyethylenated (OE) non-ionic surfactants comprising at least 10 OE units can be chosen from the following categories:

• oxyethylenated (C8-C24)alkylphenols,

• saturated or unsaturated, linear or branched, oxyethylenated, C ₈ -C ₃₀ and preferably C12-C22 fatty alcohols,

• saturated or unsaturated, linear or branched, oxyethylenated, C8-C30 amides, • esters of saturated or unsaturated, linear or branched, C8-C30 acids and of polyethylene glycols,

• polyoxyethylenated esters of saturated or unsaturated, linear or branched, Cs- C30 acids and of sorbitol,

• saturated or unsaturated, oxyethylenated plant oils,

and mixtures thereof.

Preferably, the oxyethylenated non-ionic surfactant comprising at least 10 OE units and the oxyethylenated non-ionic surfactant comprising from 1 to 9 OE units are chosen from oxyethylenated, saturated or unsaturated, linear or branched, preferably linear, C8-C30, preferably C12-C22 and better still C14-C20, fatty alcohols, for instance cetyl alcohol, oleyl alcohol, oleocetyl alcohol, behenyl alcohol, cetearyl alcohol and stearyl alcohol, and mixtures thereof, and more preferably stearyl alcohol.

Use is preferably made, as oxyethylenated non-ionic surfactant comprising from 1 to 9 OE units, of oxyethylenated non-ionic surfactants comprising from 2 to 8 and preferably from 2 to 4 OE units, for instance the products of addition of ethylene oxide and stearyl alcohol such as stearyl alcohol 2 OE (CTFA name: Steareth-2).

The oxyethylenated non-ionic surfactants comprising at least 10 OE units used in the invention may in particular contain a number of oxyethylene groups, ranging from 10 to 50, preferably from 15 to 30 and better still from 15 to 25, for instance the products of addition of ethylene oxide and stearyl alcohol such as stearyl alcohol 20 OE (CTFA name: Steareth-20), and mixtures thereof.

The content of oxyalkylenated, preferably oxyethylenated, non-ionic surfactant(s) comprising from 1 to 9 oxyalkylene units, preferably oxyethylene units, in the composition A and/or B according to the invention may range from 0.1 % to 15% by weight, preferably from 0.5% to 10% by weight and better still from 1 % to 6% by weight relative to the total weight of each composition A and/or B.

The content of oxyalkylenated, preferably oxyethylenated, non-ionic surfactants comprising at least 10 oxyalkylene groups, preferably oxyethylene groups, in the composition A and/or B may range from 0.1 % to 15% by weight, preferably from 0.5% to 10% by weight and better still from 1 % to 6% by weight relative to the total weight of the composition A and/or B. The total amount of oxyalkylenated, preferably oxyethylenated, non-ionic surfactants in the composition A and/or B may range from 1 % to 25% by weight, preferably from 2% to 15% by weight and better still from 3% to 7% by weight relative to the total weight of each composition A and/or B.

According to one embodiment, the composition B of the process according to the invention comprises at least one oxyethylenated (OE) non-ionic surfactant comprising a number of OE units ranging from 1 to 9 and at least one oxyethylenated (OE) non-ionic surfactant comprising at least 10 OE units.

Preferably, the weight ratio, in the composition B of the invention, of the amount of oxyethylenated non-ionic surfactant(s) comprising a number of OE units ranging from 1 to 9 to the amount of oxyethylenated non-ionic surfactant(s) comprising at least 10 OE units is greater than 1 , preferably greater than or equal to 1.2, better still greater than or equal to 1.5 and even better still greater than or equal to 2.

This weight ratio may range, for example, from 1 to 15, better still from 1 to 10 and even better still from 1 to 5.

According to one embodiment, the composition A of the process according to the invention comprises at least one oxyethylenated (OE) non-ionic surfactant comprising a number of OE units ranging from 1 to 9 and at least one oxyethylenated (OE) non-ionic surfactant comprising at least 10 OE units.

Preferably, the weight ratio, in the composition A of the invention, of the amount of oxyethylenated non-ionic surfactant(s) comprising a number of OE units ranging from 1 to 9 to the amount of oxyethylenated non-ionic surfactant(s) comprising at least 10 OE units is less than 1 , preferably less than or equal to 0.9, better still less than or equal to 0.8 and even better still less than or equal to 0.7.

This weight ratio may range, for example, from 0.1 to 0.9, better still from 0.2 to 0.8 and even better still from 0.3 to 0.6.

According to one preferred embodiment, the composition A and the composition B of the process according to the invention comprise at least one oxyethylenated (OE) non- ionic surfactant comprising a number of OE units ranging from 1 to 9 and at least one oxyethylenated (OE) non-ionic surfactant comprising at least 10 OE units.

According to one embodiment, the combination of the oxyethylenated non-ionic surfactant comprising at least 10 OE units and the oxyethylenated non-ionic surfactant comprising from 1 to 9 OE units constitutes the main surfactant system of the composition A and/or B.

The term "main surfactant system" is intended to mean a system which, in its absence, does not lead to the formation of a stable composition.

The term "stable" is intended to mean a composition which, after having been placed in an oven at 45°C for two months, does not show, after returning to ambient temperature, any phase separation.

According to a particular embodiment, the combination of the oxyalkylenated, preferably oxyethylenated, non-ionic surfactant(s) comprising at least 10 OA units, preferably OE units, and of the oxyalkylenated, preferably oxyethylenated, non-ionic surfactant(s) comprising from 1 to 9 OA units, preferably OE units, constitutes the sole surfactant system of the composition A and/or B.

The term "sole" is intended to mean that any possible additional surfactant system is present in a content not exceeding 1 %, and preferably not exceeding 0.5%. More preferably, the term "sole" denotes a total absence of any other surfactant system. According to a particular embodiment, the composition A and/or B comprises a single oxyalkylenated, preferably oxyethylenated, non-ionic surfactant comprising at least 10 OA units, preferably OE units, and a single oxyalkylenated, preferably oxyethylenated, non-ionic surfactant comprising from 1 to 9 OA units, preferably OE units, as sole surfactant system.

The composition A and/or the composition B according to the invention preferably comprises a cosmetically acceptable medium. For the purposes of the present invention, the term “cosmetically acceptable medium” is intended to mean a medium that is compatible with keratin materials, in particular keratin fibres, and in particular human keratin fibres such as the hair.

The cosmetically acceptable medium of the composition in accordance with the present invention generally comprises water and/or one or more water-soluble organic solvents. Examples of water-soluble organic solvents that may be mentioned include Ci- C ₄ lower alkanols, such as ethanol and isopropanol; aromatic alcohols such as benzyl alcohol or phenoxyethanol; polyols or polyol ethers such as ethylene glycol monomethyl, monoethyl and monobutyl ether, propylene glycol or ethers thereof such as propylene glycol monomethyl ether, butylene glycol, dipropylene glycol, and also diethylene glycol alkyl ethers, for instance diethylene glycol monoethyl ether or monobutyl ether, or alternatively glycerol; and also mixtures thereof. The organic solvents are preferably present in proportions of between 0.1 % and 35% by weight approximately, and even more preferentially between 1% and 40% by weight approximately, relative to the total weight of the composition A or B.

The composition A and/or B in accordance with the invention may also comprise additional compounds conventionally used in cosmetics. These compounds may especially be chosen from thickening or stabilizing polymers, non-silicone conditioning polymers, especially cationic non-silicone polymers, chelating agents and fragrances.

According to another embodiment, the composition B according to the invention is free of thickening polymer.

The composition A may comprise at least one fatty substance such as those described above for the composition B, preferences included, and/or at least one surfactant, preferably non-ionic, as described in the composition B, preferences included.

Needless to say, those 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 composition in accordance with the invention are not, or are not substantially, adversely affected by the envisaged addition(s).

The compositions A and B according to the invention may be in various forms, such as in the form of a cream, a gel, a milk, a lotion or a mousse, or in any other form that is suitable for treating keratin materials, in particular keratin fibres, and especially human keratin fibres such as the hair. Preferably, they are in the form of a cream or a milk.

The pH of the dyeing and/or lightening composition resulting from mixing A and B is advantageously between 3 and 12, preferably between 5 and 11 and preferentially between 7 and 11 , limits inclusive.

It may be adjusted to the desired value by means of acidifying or basifying agents customarily used in the dyeing of keratin fibres, or alternatively using standard buffer systems.

The alkaline and acidifying agents are, for example, those described previously. The compositions (A) and (B) are preferably mixed at the time of use in an (A)/(B) weight ratio preferably ranging from 1 :1 to 1 :3.

According to the process according to the invention, the dyeing and/or lightening composition resulting from mixing the compositions A and B as defined above is applied to dry or wet keratin fibres. It is left in place on the fibres for a time generally ranging from 1 minute to 1 hour and preferably from 5 minutes to 55 minutes.

The temperature during the dyeing process conventionally ranges from ambient temperature (between 15°C and 25°C) to 80°C, preferably from ambient temperature to 60°C.

After the treatment, the human keratin fibres are optionally rinsed with water, optionally washed with a shampoo and then rinsed with water, before being dried or left to dry.

Another subject of the invention is a composition (C) for dyeing and/or lightening keratin materials, in particular keratin fibres, comprising, in a cosmetically acceptable medium:

- at least one (bi)carbonate,

- ammonium hydroxide,

- optionally at least one colouring agent,

- at least one fatty substance, which is preferably liquid, in a content of greater than or equal to 25% by weight relative to the total weight of the composition,

- at least one oxyalkylenated (OA), preferably oxyethylenated (OE), non-ionic surfactant comprising a number of OA units, preferably OE units, ranging from 1 to 9,

- at least one oxyalkylenated (OA), preferably oxyethylenated (OE), non-ionic surfactant comprising at least 10 OA units, preferably OE units,

- at least one chemical oxidizing agent, preferably hydrogen peroxide, and

- at least one neutral or acidic amino acid and/or a salt thereof.

The colouring agents, alkaline agents, oxidizing agents, oxyalkylenated (OA), preferably oxyethylenated (OE), non-ionic surfactants comprising at least 10 OA units and oxyalkylenated non-ionic surfactants comprising a number of OA units, preferably OE units, ranging from 1 to 9, that are present in the dyeing and/or lightening composition are as described above for the compositions A and B, contents and preferences included.

Finally, the invention relates to a multi-compartment device comprising a first compartment containing the composition (A) as described above and at least a second compartment containing the composition (B) as described above, the compositions in the compartments being intended to be mixed before application.

The examples that follow illustrate the invention without being limiting in nature.

EXAMPLE

The following compositions were prepared (unless otherwise mentioned, the amounts are expressed in g% of product):

Oxidizing composition (B)

At the time of use, the following mixtures are prepared:

M1 : 1 part by weight of formula A1 with 2 parts by weight of formula B1 (comparative)

M2: 1 part by weight of formula A1 with 2 parts by weight of formula B2 (comparative)

M3: 1 part by weight of formula A2 with 2 parts by weight of formula B1 (comparative)

M4: 1 part by weight of formula A2 with 2 parts by weight of formula B2 (invention)

10 g of each mixture (pH = 9.9 ± 0.1 ) are applied to a 1 g chestnut-brown natural pigmented lock (TD 4). The leave-on time is 50 minutes on a hotplate regulated at 33°C. After the leave-on time, each lock is rinsed, washed with an iNOA POST shampoo and then left to dry at 60°C.

The lightening of the locks is evaluated in the CIE L ^* a ^* b ^* system, using a Minolta Spectrophotometer CM2600D colorimeter. In this L ^* a ^* b ^* system, the three parameters denote, respectively, the intensity (L ^* ), a ^* indicates the green/red colour axis and b ^* the blue/yellow colour axis.

Results

As shown in the table below, the use of a mixture of an oxidizing composition B2 comprising more than 25% of fatty substance with a composition A2 comprising the combination of ammonium hydroxide + ammonium bicarbonate alkaline agents makes it possible to obtain a significant improvement in the lightening of the hair, in comparison with a mixture of a composition B2 and a composition A1 comprising ammonium hydroxide alone as alkaline agent or in comparison with a mixture of a composition A1 or A2 with a composition B1 comprising only 20% of fatty substance.

EXAMPLE 2

Oxidizing composition (B)

At the time of use, the following mixtures are prepared:

M5: 1 part by weight of formula A2 with 2 parts by weight of formula B2 (invention) M6: 1 part by weight of formula A3 with 2 parts by weight of formula B2 (comparative)

10 g of each mixture (pH = 9.9 ± 0.1 ) are applied to a 1 g chestnut-brown natural pigmented lock (TD 4). The leave-on time is 50 minutes on a hotplate set at 33°C.

After the leave-on time, each lock is rinsed, washed with an iNOA POST shampoo and then left to dry at 60°C.

Colorimetric evaluation the lightening is evaluated in the CIE L ^* a ^* b ^* system, according to the protocol described in the previous example.

Evaluation of the condition of the hair

The integrity of the hair is evaluated with regard to 3 parameters:

- tensile strength: the solidity of the hair which can be measured by the tensile test. This measurement for determining the tensile mechanical properties of the hair is performed using a commercial tool, the MTT600 (mini Tensile Tester) from the company Dia Stron. The modulus of elasticity of the hair is measured: the higher its value, the stronger the hair;

- qualitative evaluation of cysteic acid and/of free proteins at the surface of the hair: these compounds are released during oxidation of the hair; the higher the content of cysteic acid and free proteins, the more damaged the hair.

The cysteic acid present in the air is assayed by means of a Hitachi L8900 amino acid autoanalyser; 20 mg of finely cut hair are transferred into a culture tube (Duran). 2.5 ml of 9 N hydrochloric acid are added to the tube with magnetic stirring under nitrogen for 1 min at 2 bar.

The solution is heated in the tube in an oil bath at 1 10°C for 16 hours. The pH is adjusted between 1 .6 and 1.8 and diluted to 50 ml with ultrapure water. The solution is then filtered and analysed in the autoanalyser.

The quantitative analysis of the labile proteins is performed with the same equipment as for the assaying of the cysteic acid.

20 mg of finally cut hair are transferred into a 1.5 ml Eppendorf tube. 400 mI of 0.2 M Tris(hydroxymethyl)aminomethane base (TRIZMA base) and 400mI of 0.2 M 2- mercaptoethanol are added to the tube and stirred with a thermomixer set to 37°C for 16 hours at 700 rpm. After 16 h of extraction, the residual contents are transferred into a Duran tube using a liquipette, and concentrated under compressed air for 4 hours until complete evaporation of the solvent.

1 ml of 9 N hydrochloric acid is added to each tube and then heated for 16 hours at 110°C. The hydrolysed solution is concentrated under compressed air for 12 hours until complete evaporation, 1 ml of buffer at pH 2 is added, followed by vortexing, filtration and analysis on the Hitachi autoanalyser.

Results

The results show that a composition according to the invention makes it possible, at equivalent lightening performance qualities, to keep a better integrity of the hair (significant increase in the modulus of elasticity and lower amounts of cysteic acid and proteins) in the presence of carbonates compared with the comparative composition.

EXAMPLE 3

Oxidizing composition (B)

At the time of use, the following mixtures are prepared:

M6: 1 part by weight of formula A1 with 2 parts by weight of formula B2 (invention)

M7: 1 part by weight of formula A4 with 2 parts by weight of formula B2 (comparative) 10 g of each mixture (pH = 9.9 ± 0.1 ) are applied to a 1 g chestnut-brown natural pigmented lock (TD 4). The leave-on time is 50 minutes on a hotplate set at 33°C.

After the leave-on time, each lock is rinsed, washed with an iNOA POST shampoo and then left to dry at 60°C.

Results

The results show that a composition according to the invention makes it possible, at equivalent lightening performance qualities, to keep a better integrity of the hair (significant increase in the tensile strength and lower amount of labile proteins) in the presence of carbonates compared with the comparative composition.