WO2011076792A1 - Agent for dyeing and/or bleaching keratinous fibres in two or more parts in the form of an emulsion and of a dispersion - Google Patents

Abstract

The present invention relates to an agent for dyeing and/or bleaching keratinous fibres, comprising: - a surfactant-free water-in-oil dispersion (A), comprising: - at least 30% of one or more oils not comprising a carboxylic acid functional group, - water, - one or more basifying agents, and - optionally one or more thickening agents chosen from inorganic thickeners and associative polymers, and - a direct emulsion (B), comprising: - water, - one or more oils not comprising a carboxylic acid functional group, - one or more oxidizing agents, - one or more surfactants, and the total amount of the said oils present in the mixture of the dispersion (A) and of the emulsion (B) representing at least 20% by weight, with respect to the total weight of the said mixture. The present invention also relates to a method for dyeing and/or bleaching keratinous fibres employing such an agent and to a kit comprising it.

Description

Agent for dyeing and/or bleaching keratinous fibres in two or more parts in the form of an emulsion and of a dispersion

The present invention relates to an agent in two or more parts intended for the dyeing and/or bleaching of keratinous fibres, in particular human keratinous fibres, such as the hair.

Another subject-matter of the present invention is a method for dyeing and/or bleaching keratinous fibres employing the agent according to the invention.

Finally, the present invention relates to a multicompartment device comprising the dyeing and/or bleaching agent according to the invention and to the use of the agent in the dyeing and/or bleaching o f keratinous fibres .

For a long time, many people have attempted to modify the co lour of the hair and in particular to bleach it or, in contrast, to dye it, for example in order to conceal their white hair.

Essentially two types of dyeing operations have been developed in order to dye human keratinous fibres.

The first type of dyeing operation is "permanent" or oxidation dyeing, which employs dyeing compositions comprising oxidation dye precursors, generally known as oxidation bases . These oxidation bases are co lourless or weakly coloured compounds which, in combination with oxidizing products, can give rise, by an oxidative condensation process, to coloured compounds .

It is also known that it is possible to vary the shades obtained with these oxidation bases by combining them with couplers or co louring modifiers. The variety o f the mo lecules invo lved as oxidation bases or couplers makes it possible to obtain a rich palette of co lours.

The second type o f dyeing operation is "semipermanent" dyeing or direct dyeing, which consists in applying direct dyes to the keratinous fibres, direct dyes being co loured and colouring mo lecules having an affinity for the said fibres, in leaving to stand and in then rinsing them.

In order to carry out these dyeing operations, the direct dyes generally emp loyed are chosen from nitrobenzene, anthraquinone, nitropyridine, azo, xanthene, acridine, azine or triarylmethane direct dyes.

This type o f process does not require the use of an oxidizing agent in order to develop the co louring. However, it is possible to employ such an agent in order to obtain a lightening effect with the dyeing operation. Reference is then made to a direct or semipermanent dyeing operation under lightening conditions.

Permanent or also semipermanent dyeing methods under lightening conditions thus consist in employing, with the dyeing composition, an aqueous composition comprising at least one oxidizing agent, under alkaline pH conditions in the great majority o f cases.

The role o f this oxidizing agent is to decompose the melanin o f the hair, which, depending on the nature of the oxidizing agent present, results in a more or less pronounced lightening of the fibres. Thus, for relatively slight lightening, the oxidizing agent is generally hydrogen peroxide . When greater lightening is desired, use is normally made o f peroxygenated salts, such as, for example, persulphates, in the presence o f hydrogen peroxide.

In order to improve the performances of the methods for dyeing and/or bleaching human keratinous fibres and to limit the inconveniences related to the use of alkaline agents and of oxidizing agents, the proposal has been made to use, in the dyeing compositions, a substantial amount of one or more fatty substances.

However, the incorporation in these compositions o f a sufficient amount of fatty substance proves to be problematic, all the more so when the dyeing composition is formulated in the form o f a conventional emulsion o f oil-in-water type. This is because these formulations are thermodynamically unstable and their viscosity changes over time, all the more so if the amount of fatty substance is high.

Generally, these emulsions are stabilized with surfactants o f oxyalkylenated fatty alcoho l type. In point of fact, the dyeing compositions stabilized with these surfactants exhibit colourings which are not always satisfactory. This is because it has been observed that these surfactants have a tendency to slow down the uptake of the co lour in the individual hair.

The Applicant Company has now discovered that the act of employing an alkaline composition in the form o f a dispersion makes it possible to incorporate a large amount of oily compounds in the compositions applied to the fibres, while reducing the amount o f surfactants. It has been observed that the mixture of a surfactant-free dispersion according to the invention and o f a direct oil-in-water emulsion comprising an oxidizing agent makes it possible to obtain more intense co lourings.

Furthermore, the addition o f a specific thickener makes it possible to stabilize the dispersion obtained. The formulation o f the dyeing composition in the form o f a dispersion makes it possible to achieve better protection of the dyes, which are less subj ect to oxidation by atmospheric oxygen. This formulation thus results in more intense and more chromatic co lourings being obtained.

A subj ect-matter of the invention is thus an agent for dyeing and/or bleaching keratinous fibres, comprising :

- a surfactant-free dispersion (A) of water in oil(s), comprising :

- at least 30% by weight of the total weight of the dispersion o f one or more oils not comprising a carboxylic acid functional group,

- water,

- one or more basifying agents, and

- optionally one or more thickening agents chosen from inorganic thickeners and associative po lymers, and

- a direct oil-in-water emulsion (B) comprising :

- water, - one or more oils not comprising a carboxylic acid functional group,

- one or more oxidizing agents, and

- one or more surfactants,

the total amount of the said oils present in the mixture of the dispersion (A) and of the emulsion (B) representing at least 20% by weight, with respect to the total weight of the said mixture.

When the agent according to the invention is intended for the dyeing of keratinous fibres, the dispersion (A) additionally comprises one or more oxidation dyes and/or one or more direct dyes .

Conversely, when the agent according to the invention is intended for just the bleaching of the keratinous fibres, the dispersion (A) and the emulsion (B) do not comprise direct dye or oxidation dye precursor (bases and couplers) or else, if they are present, their total content does not exceed 0.005 % by weight, with respect to the weight of each composition. This is because, at such a content, only the composition would be dyed, that is to say that no effect of dyeing the keratinous fibres would be observed.

The dyeing and/or bleaching agent according to the present invention does not change or changes only slightly over time during the mixing of the dispersion (A) and of the emulsion (B) or during the sequential application o f these two compositions on the keratinous fibres . It thus exhibits a very good effectiveness, in particular in terms of quality and homogeneity o f the dyeing and/or bleaching.

In addition, when it is intended for the dyeing, the agent according to the invention is particularly effective with regard to the power of the co louring obtained and that of the chromaticity and with regard to the selectivity o f the colouring of the same fibre or between fibres sensitized to different extents .

When it is intended for the bleaching, the agent according to the invention exhibits a lightening performance equivalent to , and even better than, that obtained with the existing compositions, in particular for those based on ammonium hydroxide. The agent according to the invention also exhibits the advantage of limiting the release of an offensive odour during its preparation or its application on the fibres .

Other characteristics and advantages of the invention will become more clearly apparent on reading the description and examples which fo llow.

In that which will fo llow and unless otherwise indicated, the limits o f a range o f values are included within this range.

The human keratinous fibres treated by the method according to the invention are preferably the hair.

The term "emulsion" is understood to mean, within the meaning o f the present invention, true emulsions, to be distinguished from microemulsions, which are thermo dynamically stable systems. The emulsion requires an emulsifier in order to be stable.

The term "dispersion" is understood to mean, within the meaning o f the present invention, a heterogeneous system not comprising an emulsifier, in which a finely divided material, such as, for example, a fatty phase, is distributed in another material, such as an aqueous phase.

The size o f the droplets of the dispersed phase of the emulsions of use in the invention is preferably between 10 nm and 100 μιη and preferably between 200 nm and 50 μιη.

It is the D(3 ,2) mean diameter which can be measured in particular using a laser particle sizer.

The dispersion (A) and the direct emulsion (B) can be prepared by conventional methods for the preparation of emulsions and o f dispersions well known to a person skilled in the art.

The dispersion (A) occurs in the form of a dispersion of an aqueous phase in a fatty phase.

Preferably, the dispersion (A) comprises from 30 to 70% by weight, with respect to the weight of the dispersion (A) , of one or more oils not comprising a carboxylic acid functional group, preferably from 40 to 65 % by weight. The dispersion (A) of the invention comprises water, preferably in an amount of between 5 and 50% by weight, better still from 10 to 40% by weight, of the total weight of the dispersion.

In another alternative form, the aqueous phase comprising water and the compounds soluble in water at ambient temperature and at atmospheric pressure of the dispersion comprises from 1 0 to 70%>, better still from 15 to 50%, of the total weight of the dispersion.

The dispersion (A) of use in the agent of the invention is devoid o f any surfactant. The term "devoid o f surfactants" is understood to mean, within the meaning of the present invention, devoid o f any nonpo lymeric compound exhibiting an HLB of greater than or equal to 1 .

The dispersion (A) is in particular devoid of any compound resulting solely from the simple condensation of an alkylene oxide with a fatty alcoho l, a fatty ester, a fatty acid, a fatty amide or else a fatty amine.

On the other hand, the dispersion (A) can comprise po lymeric compounds which are any compound resulting from the polymerization by po lycondensation or from the radical polymerization o f monomers, at least one of which is other than an alkylene oxide and a mono functional compound o f formula RX, R denoting an optionally hydroxylated C 10-C30 alkyl or alkenyl group and X denoting a carboxylic acid, amine, amide, hydroxyl or ester group .

According to the present invention, the dispersion (A) comprises one or more basifying agents .

The basifying agent can in particular be an inorganic or organic base.

Preferably, the basifying agent is chosen from aqueous ammonia, alkaline carbonates, alkanolamines and their derivatives, sodium hydroxide, potassium hydroxide and compounds of fo llowing formula (I) : Rx Rz

\ /

N W N

Ry Rt

(I)

in which W is a C i -C₆ alkylene residue optionally substituted by a hydroxyl group or a C i -C₆ alkyl radical and Rx, Ry, Rz and Rt, which are identical or different, represent a hydrogen atom or a C i -C₆ alkyl or C i -C₆ hydroxyalkyl or amino(C i -C₆ alkyl) radical.

Mention may be made, as examples of such compounds o f formula (II), of 1 ,3 -diaminopropane, 1 ,3 -diamino-2-propanol, spermine or spermidine.

The basifying agents which are particularly preferred are the alkano lamines and in particular the mono-, di- and triethano lamines.

In a preferred alternative form o f the invention, the basifying agent is monoethanolamine.

According to a specific embodiment, the dispersion comprises, as basifying agents, at least one organic amine, preferably at least one alkano lamine .

When the dispersion comprises several alkaline agents, including alkano lamine and aqueous ammonia or one of its salts, the organic amine or amines are preferably predominant by weight, with respect to the amount of aqueous ammonia.

According to a preferred embodiment of the present invention, the dispersion (A) does not comprise aqueous ammonia.

According to one embodiment of the present invention, when the dispersion (A) comprises aqueous ammonia, it also comprises one or more alkano lamines and the amount by weight of alkano lamine(s) in the dispersion (A) is greater than the amount of aqueous ammonia in the same dispersion.

Generally, the dispersion (A) exhibits a content of basifying agent(s) ranging from 0. 1 to 40% by weight, preferably from 0.5 to 20% by weight, with respect to the weight of this dispersion.

Preferably, the dispersion (A) and/or the aqueous phase of the dispersion (A) exhibits a pH o f greater than or equal to 8 and more preferably a pH ranging from 8.5 to 1 1 .5. This H can also be adjusted to the desired value by the use, in addition to the basifying agent, of one or more acidifying agents .

Mention may be made, among acidifying agents, by way o f examples, of inorganic or organic acids, such as hydrochloric acid, orthophosphoric acid, sulphuric acid, carboxylic acids, such as acetic acid, tartaric acid, citric acid or lactic acid, or sulphonic acids.

The dispersion (A) according to the present invention can comprise one or more thickening agents chosen from inorganic thickeners and associative po lymers.

The thickening agents can be inorganic thickeners chosen from organophilic clays .

The organophilic clay can be chosen from montmorillonite, bentonite, hectorite, attapulgite, sepiolite and their mixtures, the clay optionally being modified. The clay is preferably a bentonite or a hectorite .

These clays can be modified with a chemical compound chosen from quaternary ammoniums, tertiary amines, amine acetates, imidazo lines, amine soaps, fatty sulphates, alkylarylsulphonates, amine oxides and their mixtures .

Mention may be made, as organophilic clays, of quaternary- 1 8 bentonites, such as those sold under the names Bentone 3 , Bentone 38 or Bentone 38V by Rheox, Tixogel VP by United Catalyst or Claytone 34, Claytone 40 or Claytone XL by Southern Clay; stearalkonium bentonites, such as those sold under the names Bentone 27 by Rheox, Tixogel LG by United Catalyst or Claytone AF or Claytone APA by Southern Clay; or quaterium- 1 8/benzalkonium bentonites, such as those so ld under the names Claytone HT or Claytone PS by Southern Clay.

The preferred inorganic thickening agents are chosen from organomodified hectorites or bentonites .

More particularly, the thickening agent used is a distearyldimethylammonium-modified hectorite .

Preferably, the inorganic thickeners are used in combination with carbonates, such as, for example, propylene carbonate. The thickening agents can also be chosen from thickening systems based on associative polymers well known to a person skilled in the art and in particular o f nonionic, anionic, cationic or amphoteric nature.

It should be remembered that associative po lymers are hydrophilic polymers capable, in an aqueous medium, of reversibly combining with one another or with other mo lecules. Their chemical structure more particularly comprises at least one hydrophilic region and at least one hydrophobic region. The term "hydrophobic group" is understood to mean a radical or polymer comprising a saturated or unsaturated and linear or branched hydrocarbon chain comprising at least 8 carbon atoms, preferably from 10 to 30 carbon atoms, in particular from 12 to 30 carbon atoms and more preferably from 1 8 to 30 carbon atoms . Preferably, the hydrocarbon group originates from a mono functional compound. By way o f example, the hydrophobic group can result from a fatty alcoho l, such as stearyl alcoho l, dodecyl alcoho l or decyl alcoho l. It can also denote a hydrocarbon polymer, such as, for example, polybutadiene.

Preferably, the dispersion (A) can thus comprise at least one associative po lymer chosen from associative polyurethanes which are more particularly cationic or nonionic, associative cellulo se derivatives which are more particularly cationic or nonionic, associative vinyllactams, associative unsaturated polyacids, associative aminoplast ethers, associative po lymers or copolymers comprising at least one monomer comprising ethylenic unsaturation and comprising a sulpho group, alone or as mixtures.

Mention may be made, among associative thickening po lymers, of associative polyurethane derivatives, such as those obtained by polymerization:

- approximately 20% to 70% by weight of a carboxylic acid comprising α, β-monoethylenic unsaturation,

- approximately 20 to 80% by weight of a non-surface-active monomer comprising α, β-monoethylenic unsaturation other than the above, - approximately 0.5 to 60% by weight of a nonionic monourethane which is the reaction product of a monohydroxylated surfactant with a monoisocyanate comprising monoethylenic unsaturation.

Such are described in particular in EP 173 109 and more particularly in Example 3. More specifically, this polymer is a methacrylic acid/methyl acrylate/ethoxylated (40 EO) behenyl alcoho l dimethyl(meta-isopropenyl)benzyl isocyanate terpolymer as a 25 % aqueous dispersion. This product is provided under the reference Viscophobe DB 1000 by Amercho l.

The cationic associative po lyurethanes from the family described in Application FR 0009609 are also suitable. They can be represented more particularly by the fo llowing general formula (A) :

R-X-(P)n- [L-(Y)m]r-L^*-(P^,)p-X^,-R^* (A)

in which:

R and R' , which are identical or different, represent a hydrophobic group or a hydrogen atom;

X and X' , which are identical or different, represent a group comprising an amine functional group which does or does not carry a hydrophobic group, or also the L" group;

L, L ' and L", which are identical or different, represent a group derived from a diisocyanate;

P and P ' , which are identical or different, represent a group comprising an amine functional group which does or does not carry a hydrophobic group;

Y represents a hydrophilic group;

r is an integer between 1 and 100, preferably between 1 and 50 and in particular between 1 and 25 ;

n, m and p have values, each independently o f the others, between 0 and 1000;

the mo lecule comprising at least one protonated or quaternized amine functional group and at least one hydrophobic group . In a highly advantageous embodiment, the only hydrophobic groups of these polyurethanes are the R and R' groups situated at the chain ends.

According to a first preferred embodiment, the associative polyurethane corresponds to the formula (A) in which R and R' both independently represent a hydrophobic group; X and X' each represent an L" group; n and p have values between 1 and 1000 and L, L ' , L", P, P ' , Y and m have the meanings indicated in the formula (A) .

According to another preferred embodiment of the invention, the associative po lyurethane corresponds to the formula (A) in which R and R' both independently represent a hydrophobic group, X and X' each represent an L" group, n and p have values of 0 , and L, L ' , L", Y and m have the meanings in the formula (A) indicated above.

The fact that n and p have values of 0 means that these polymers do not comprise units derived from a monomer comprising an amine functional group incorporated in the po lymer during the polycondensation. The protonated amine functional groups o f these polyurethanes result from the hydrolysis o f isocyanate functional groups, in excess, at the chain end, followed by the alkylation, o f the primary amine functional groups formed, by alkylating agents comprising a hydrophobic group, that is to say compounds o f RQ or R' Q type in which R and R' are as defined above and Q denotes a leaving group , such as a halide, a sulphate, and the like.

In accordance with another preferred embodiment of the invention, the associative po lyurethane corresponds to the formula (A) in which R and R' both independently represent a hydrophobic group; X and X' both independently represent a group comprising a quaternary amine; n and p have values of zero and L, L ' , Y and m have the meanings indicated in the formula (A) .

The number-average mo lecular weight of the cationic associative po lyurethanes is usually between 400 and 500 000, in particular between 1000 and 400 000 and ideally between 1000 and 300 000 g/mo l. When X and/or X' denote a group comprising a tertiary or quaternary amine, X and/or X' can represent one of the following formulae:

in which:

R₂ represents a linear or branched alkylene radical having from 1 to 20 carbon atoms which does or does not comprise a saturated or unsaturated ring, or an arylene radical, it being possible for one or more of the carbon atoms to be replaced by a heteroatom chosen from N, S, O or P;

Ri and R3, which are identical or different, denote a linear or branched C₁-C30 alkyl or alkenyl radical or an aryl radical, it being possible for at least one of the carbon atoms to be replaced by a heteroatom chosen from N, S, O or P;

A^" is a physiologically acceptable counterion.

The L, L' and L" groups represent a group of formula:

— Z-C-NH-R₄-NH-C-Z—

II II

O O

in which:

Z represents -0-, -S- or -NH-; and

R₄ represents a linear or branched alkylene radical having from 1 to 20 carbon atoms which does or does not comprise a saturated or unsaturated ring, or an arylene radical, it being possible for one or more of the carbon atoms to be replaced by a heteroatom chosen from N, S, O and P. The P and P' groups comprising an amine functional group can represent at least one of the following formulae:

1*6 ¾

N

or -R5-CH-R7 or — R5-CH-R7—

Ri N-R> A^"

1*8

1*6 _x 1*8

N

— R5-CH-R7—

^Rio

or R₁₀

or -R5-CH-R7-

«6— N-R9 A^" in which:

P5 and R₇ have the same meanings as R₂ defined above;

R₆, R8 and R9 have the same meanings as Ri and R3 defined above;

Rio represents a linear or branched alkylene group which is optionally unsaturated and which can comprise one or more heteroatoms chosen from N, O, S and P;

A^" is a cosmetically acceptable counterion.

As concerns the meaning of Y, the term "hydrophilic group" is understood to mean a polymeric or nonpolymeric water-soluble group. Mention may be made, by way of example, when polymers are not concerned, of ethylene glycol, diethylene glycol and propylene glycol.

When, in accordance with a preferred embodiment, a hydrophilic polymer is concerned, mention may be made, as example, of polyethers, sulphonated polyesters, sulphonated polyamides or a blend of these polymers. Preferably, the hydrophilic compound is a polyether and in particular a po ly(ethylene oxide) or poly(propylene oxide) .

The associative po lyurethanes o f formula (A) are formed from diisocyanates and various compounds having functional groups comprising a labile hydrogen. The functional groups comprising a labile hydrogen can be alcoho l, primary or secondary amine or thio l functional groups giving, after reaction with the diiso cyanate functional groups, polyurethanes, polyureas and polythioureas respectively. The term "po lyurethanes" of the present invention encompasses these three types o f po lymer, namely po lyurethanes proper, polyureas and polythioureas, and also copolymers of these.

A first type of compound participating in the preparation o f the polyurethane of formula (A) is a compound comprising at least one unit comprising an amine functional group . This compound can be polyfunctional but the compound is preferably difunctional, that is to say that, according to a preferred embodiment, this compound comprises two labile hydrogen atoms carried, for example, by a hydroxyl, primary amine, secondary amine or thio l functional group . Use may also be made o f a mixture o f polyfunctional and difunctional compounds in which the percentage o f polyfunctional compounds is low.

As indicated above, this compound can comprise more than one unit comprising an amine functional group . It is then a polymer carrying a repetition of the unit comprising an amine functional group .

This type o f compound can be represented by one of the fo llowing formulae :

HZ-(P)_n-ZH, or HZ-(P^*)_p-ZH

in which Z, P, Ρ ' , n and p are as defined above.

Mention may be made, as examples o f compound comprising an amine functional group, of N-methyldiethano lamine, N-(tert- butyl)diethanolamine or N-sulphoethyldiethanolamine.

The second compound participating in the preparation of the polyurethane of formula (A) is a diisocyanate corresponding to the formula 0=C=N- R4-N=C=0, in which R₄ is defined above. Mention may in particular be made of methylenediphenyl diisocyanate, methylenecyclohexane diisocyanate, isophorone diisocyanate, toluene diisocyanate, naphthalene diisocyanate, butane diisocyanate or hexane diisocyanate.

A third compound participating in the preparation o f the polyurethane of formula (A) is a hydrophobic compound intended to form the terminal hydrophobic groups of the polymer of formula (A) .

This compound is composed o f a hydrophobic group and of a functional group comprising a labile hydrogen, for example a hydroxyl, primary amine, secondary amine or thio l functional group .

By way o f example, this compound can be a fatty alcoho l, such as, in particular, stearyl alcoho l, dodecyl alcoho l or decyl alcoho l. When this compound comprises a polymer chain, it can, for example, be a-hydroxylated hydrogenated polybutadiene.

The hydrophobic group of the polyurethane of formula (A) can also result from the quaternization reaction of the tertiary amine o f the compound comprising at least one tertiary amine unit. Thus, the hydrophobic group is introduced by the quaternizing agent. This quaternizing agent is a compound of RQ or R' Q type in which R and R' are as defined above and Q denotes a leaving group , such as a halide, a sulphate, and the like.

The cationic associative po lyurethane can additionally comprise a hydrophilic sequence. This sequence is contributed by a fourth type of compound participating in the preparation o f the polymer. This compound can be polyfunctional. It is preferably difunctional. It is also possible to have a blend where the percentage of polyfunctional compound is low.

The functional groups comprising a labile hydrogen are alcoho l, primary amine, secondary amine or thio l functional groups . This compound can be a polymer terminated at the ends of the chains by one of these functional groups comprising a labile hydrogen.

Mention may be made, as examples, when polymers are not concerned, of ethylene glycol, diethylene glycol and propylene glycol. When a hydrophilic po lymer is concerned, mention may be made, as examples, of polyethers, sulphonated polyesters, sulphonated polyamides or a blend o f these po lymers.

Preferably, the hydrophilic compound is a polyether and in particular a poly(ethylene oxide) or poly(propylene oxide) .

The hydrophilic group denoted Y in the formula (A) is optional. This is because the units comprising a quaternary or protonated amine functional group may be sufficient to introduce the so lubility or water-dispersibility necessary for this type o f po lymer in an aqueous so lution.

Although the presence of a hydrophilic Y group is optional, preference is given, however, to cationic associative polyurethanes comprising such a group .

The associative po lyurethane derivatives of the invention can also be nonionic po lyether po lyurethanes. More particularly, the said polymers comprise, in their chain, both hydrophilic sequences o f generally po lyoxyethylene nature and hydrophobic sequences which can be aliphatic linkages alone and/or cycloaliphatic and/or aromatic linkages .

Preferably, these polyether polyurethanes comprise at least two lipophilic hydrocarbon chains having from 6 to 30 carbon atoms which are separated by a hydrophilic sequence, it being possible for the hydrocarbon chains to be pendent chains or chains at the end of the hydrophilic sequence. In particular, it is possible for one or more pendent chains to be provided. In addition, the polymer can comprise a hydrocarbon chain at one end or at both ends of a hydrophilic sequence.

The po lyether polyurethanes can be multiblo ck, in particular in the triblock form. The hydrophobic sequences can be at each end of the chain (for example : triblock copolymer comprising a hydrophilic central sequence) or distributed both at the ends and in the chain (multiblock copolymer, for example) . These same polymers can also be graft or star polymers .

The nonionic po lyether po lyurethanes comprising a fatty chain can be triblock copolymers, the hydrophilic sequence of which is a polyoxyethylene chain comprising from 50 to 1000 oxyethylene groups.

The nonionic polyether polyurethanes comprise a urethane bond between the hydrophilic sequences, hence the origin of the name.

By extension, the nonionic polyether polyurethanes comprising a hydrophobic chain also include those having hydrophilic sequences bonded to the hydrophobic sequences via other chemical bonds.

Use may also be made, as examples of nonionic polyether polyurethanes comprising a hydrophobic chain which can be used in the invention, of Rheolate 205® comprising a urea functional group sold by Rheox or also Rheolates® 208, 204 or 212, and also Acrysol RM 184®.

Mention may also be made of the product Elfacos T210® comprising a C₁₂-C₁₄ alkyl chain and the product Elfacos T212® comprising a C₁₈ alkyl chain from Akzo.

The product DW 1206B® from Rohm & Haas comprising a C₂o alkyl chain and comprising a urethane bond, provided at a solids content of 20% in water, can also be used.

Use may also be made of solutions or dispersions of these polymers, in particular in water or in an aqueous/alcoholic medium.

Mention may be made, as examples of such polymers, of Rheolate®

255, Rheolate® 278 and Rheolate® 244, sold by Rheox. Use may also be made of the products DW 1206F and DW 1206J provided by Rohm & Haas.

The polyether polyurethanes which can be used described above can also be chosen from those described in the paper by G. Fonnum, J. Bakke and Fk. Hansen, Colloid Polym. Sci., 271, 380- 389 (1993).

More particularly still, according to the invention, preference is given to the use of a polyether polyurethane capable of being obtained by polycondensation of at least three compounds comprising (i) at least one polyethylene glycol comprising from 150 to 180 mol of ethylene oxide, (ii) stearyl alcohol or decyl alcohol and (iii) at least one diisocyanate.

Such polyether polyurethanes are sold in particular by Rohm & Haas under the names Aculyn 46® and Aculyn 44® [Aculyn 46® is a polycondensate of polyethylene glycol comprising 150 or 180 mol of ethylene oxide, of stearyl alcohol and of methylenebis(4-cyclohexyl isocyanate) (SMDI), at 15% by weight in a matrix of maltodextrin (4%>) and of water (81%>); Aculyn 44® is a polycondensate of polyethylene glycol comprising 150 or 180 mol of ethylene oxide, of decyl alcohol and of methylenebis(4-cyclohexyl isocyanate) (SMDI), at 35%) by weight in a mixture of propylene glycol (39%>) and of water (26%)].

The dispersion (A) can likewise comprise polymers derived from associative celluloses, such as:

- quaternized cationic celluloses modified by groups comprising at least one hydrophobic chain, such as alkyl, arylalkyl or alkylaryl groups comprising at least 8 carbon atoms, or blends of these,

- quaternized cationic hydroxyethylcelluloses modified by groups comprising at least one hydrophobic chain, such as alkyl, arylalkyl or alkylaryl groups comprising at least 8 carbon atoms, or blends of these.

The alkyl radicals carried by the above quaternized celluloses or hydroxyethylcelluloses preferably comprise from 8 to 30 carbon atoms. The aryl radicals preferably denote the phenyl, benzyl, naphthyl or anthryl groups.

There may be indicated, as examples of quaternized alkylhydroxyethylcelluloses comprising a C8-C30 hydrophobic chain, the products Quatrisoft LM 200®, Quatrisoft LM-X 529-18-A®, Quatrisoft LM-X 529-18B® (C₁₂ alkyl) and Quatrisoft LM-X 529-8® (Ci8 alkyl) sold by Amerchol and the products Crodacel QM®, Crodacel QL® (C12 alkyl) and Crodacel QS® (Ci₈ alkyl) sold by Croda.

- nonionic cellulose derivatives, such as hydroxyethylcelluloses modified by groups comprising at least one hydrophobic chain, such as alkyl, arylalkyl or alkylaryl groups, or their blends, and in which the alkyl groups are preferably C8-C22 alkyl groups, such as the product Natrosol Plus Grade 330 CS® (C₁₆ alkyls) sold by Aqualon or the product Bermocoll EHM 100® sold by Berol Nobel,

- cellulose derivatives modified by alkylphenyl polyalkylene glycol ether groups, such as the product Amercell Polymer HM-1500® sold by Amerchol.

As regards the associative polyvinyllactams, mention may be made, for example, of the polymers described in particular in FR 0101106. The said polymers are more particularly cationic polymers and comprise:

- a) at least one monomer of vinyllactam or alkylvinyllactam typ

- b) at least one monomer with the following structures (a)

.R,

/ ³

ΟΗ-0(^)-00-Χ-(Υ)_ρ— (CH₂-CH₂-0)— (CH₂-CH(R₂)-0)_n— (Y _q

R₄

(b)

in which:

X denotes an oxygen atom or an NR₆ radical,

Ri and R₆ denote, independently of one another, a hydrogen atom or a linear or branched C1-C5 alkyl radical,

R₂ denotes a linear or branched C1-C4 alkyl radical,

R3, R₄ and R₅ denote, independently of one another, a hydrogen atom, a linear or branched C1-C30 alkyl radical or a radical of formula (c):

— (Y₂)— (CH₂-CH(R₇)-0)_x R₈ (c)

Y, Yi and Y₂ denote, independently of one another, a linear or branched C₂-Ci6 alkylene radical, R₇ denotes a hydrogen atom, a linear or branched C₁-C4 alkyl radical or a linear or branched C₁-C4 hydroxyalkyl radical,

R-8 denotes a hydrogen atom or a linear or branched C₁-C30 alkyl radical,

p, q and r denote, independently of one another, either the value 0 or the value 1,

m and n denote, independently of one another, an integer ranging from 0 to 100,

x denotes an integer ranging from 1 to 100,

Z denotes an organic or inorganic acid anion,

with the proviso that:

- at least one of the substituents R₃, R₄, R5 or R₈ denotes a linear or branched C9-C30 alkyl radical,

- if m or n is other than zero, then q is equal to 1,

- if m or n are equal to zero, then p or q is equal to 0.

The poly(vinyllactam) polymers may or may not be crosslinked and may also be block polymers.

Preferably, the counterion Z^" of the monomers of formula (b) is chosen from halide ions, phosphate ions, the methosulphate ion or the tosylate ion.

Preferably, R₃, R₄ and R₅ denote, independently of one another, a hydrogen atom or a linear or branched C₁-C30 alkyl radical.

More preferably, the monomer b) is a monomer of formula (b) for which, more preferably still, m and n are equal to zero.

The vinyllactam or alkylvinyllactam monomer is preferably a compound with the structure (d):

CH(R₉)=C(R₁₀)-N_^O (d)

(CH₂)_S

in which:

s denotes an integer ranging from 3 to 6,

R9 denotes a hydrogen atom or a C₁-C5 alkyl radical,

Rio denotes a hydrogen atom or a C₁-C5 alkyl radical,

with the proviso that at least one of the radicals R9 and Rio denotes a hydrogen atom. More preferably still, the monomer (d) is vinylpyrro lidone. The poly(vinyllactam) polymers can also comprise one or more additional monomers, preferably cationic or nonionic monomers.

Mention may be made, as compounds which are more particularly preferred according to the invention, o f the fo llowing terpolymers comprising at least :

a) - one monomer of formula (d),

b) - one monomer o f formula (a) in which p = 1 , q = 0, R₃ and R₄ denote, independently o f one another, a hydrogen atom or a C 1 - C 5 alkyl radical and R₅ denotes a Cc> - C₂₄ alkyl radical and

c) - one monomer o f formula (b) in which R₃ and R₄ denote, independently o f one another, a hydrogen atom or a C 1 - C 5 alkyl radical.

More preferably still, use is made o f terpolymers comprising, by weight, 40 to 95 % of monomer (d), 0. 1 to 55 %> of monomer (b) and 0.25 to 50% of monomer (b).

Such polymers are described in particular in Patent Application WO 00/68282, the content of which forms an integral part of the invention.

Use may in particular be made, as po ly(vinyllactam) polymers, of vinylpyrrolidone/dimethylaminopropylmethacrylamide/dodecyl- dimethylmethacrylamidopropylammonium tosylate terpolymers, vinylpyrro lidone/dimethylaminopropylmethacrylamide/cocoyldimeth- ylmethacrylamidopropylammonium tosylate terpolymers or vinylpyrro lidone/dimethylaminopropylmethacrylamide/lauryldimethyl- methacrylamidopropylammonium tosylate or chloride terpolymers . The vinylpyrro lidone/dimethylaminopropylmethacrylamide/lauryldimethyl- methacrylamidopropylammonium chloride terpolymer is provided at 20% in water by ISP under the name Styleze W20.

The associative polyvinyllactam derivatives of the invention can also be nonionic copolymers o f vinylpyrro lidone and o f hydrophobic monomers comprising a hydrophobic chain, of which mention may be made, by way o f examp le, of: - the products Antaron V216® or Ganex V2 16® (vinylpyrro lidone/hexadecene copolymer) sold by ISP,

- the products Antaron V220® or Ganex V220® (vinylpyrro lidone/eicosene copolymer) sold by ISP .

Mention may be made, among associative unsaturated polyacid derivatives, o f those comprising at least one hydrophilic unit o f olefinic unsaturated carboxylic acid type and at least one hydrophobic unit o f nonethoxylated alkyl (C _{1 0}-C₃₀) ester of unsaturated carboxylic acid type.

These po lymers are chosen in particular from those for which the hydrophilic unit o f o lefinic unsaturated carboxylic acid type corresponds to the monomer of fo llowing formula (e) :

CH ^~ C— C— OH

2 I I I

R, O (e)

in which Ri denotes H or CH₃ or C₂H₅ , that is to say acrylic acid, methacrylic acid or ethacrylic acid units, and for which the hydrophobic unit o f alkyl (C 10-C30) ester of unsaturated carboxylic acid type corresponds to the monomer o f following formula (f) :

CH₂ = C— C— OR₃ (f)

R₂ O

in which R₂ denotes H or CH₃ or C₂H₅ (that is to say, acrylate, methacrylate or ethacrylate units) and preferably H (acrylate units) or CH₃ (methacrylate units), R3 denoting a C 10-C30 and preferably C _{1 2}- C₂₂ alkyl radical.

Alkyl (C 10-C30) esters of unsaturated carboxylic acids comprise, for example, lauryl acrylate, stearyl acrylate, decyl acrylate, isodecyl acrylate and dodecyl acrylate, and the corresponding methacrylates, lauryl methacrylate, stearyl methacrylate, decyl methacrylate, isodecyl methacrylate and dodecyl methacrylate.

Anionic po lymers o f this type are, for example, described and prepared according to Patents US-3 915 921 and 4 509 949.

In this type o f anionic associative polymer, use is more particularly made of polymers formed from a mixture o f monomers comprising : essentially acrylic acid,

an ester of formula (f) as described above in which R₂ denotes H or CH₃ , R₃ denoting an alkyl radical having from 12 to 22 carbon atoms,

and a crosslinking agent which is a well-known copolymerizable polyethylenic unsaturated monomer, such as diallyl phthalate, allyl (meth)acrylate, divinylbenzene, (poly)ethylene glyco l dimethacrylate and methylenebisacrylamide.

Preference is given, among anionic associative po lymers o f this type, to those composed of 95 to 60% by weight of acrylic acid (hydrophilic unit), of 4 to 40% by weight of C 1 0 - C30 alkyl acrylate (hydrophobic unit) and of 0 to 6%> by weight of crosslinking polymerizable monomer, or else those composed of 98 to 96%> by weight of acrylic acid (hydrophilic unit), of 1 to 4% by weight of C _{1 0}- C30 alkyl acrylate (hydrophobic unit) and of 0. 1 to 0.6%> by weight o f crosslinking polymerizable monomer, such as those described above.

Preference is very particularly given, among the above-said polymers, to the products sold by Goodrich under the trade names Pemulen TR l ®, Pemulen TR2® and Carbopol 1382®, and more preferably still Pemulen TRl ®, and the product sold by SEPPIC under the name Coatex SX®.

As regards the thickening polymers of the aminoplast ether type, any product resulting from the condensation o f an aldehyde with an amine or an amide, and also any structural unit formed from an aminoplast residue and from a divalent hydrocarbon residue bonded to the aminoplast residue via an ether bond, is denoted.

The po lymers comprising an aminoplast ether backbone are preferably chosen from those comprising at least one unit with the fo llowing structure (g) :

in which:

- AMP is an aminoplast residue with alkylene (or divalent alkyl) units,

- R denotes a hydrogen atom, a C₁-C₄ alkyl radical or a C₁-C₄ acyl radical,

- ROi is a divalent alkyleneoxy residue,

- p denotes a positive integer,

- the OR group or groups being bonded to the alkylene units of the AMP residue.

Preferably, the polymers comprising an aminoplast ether backbone are chosen from those comprising at least one unit with the following structure (h):

in which:

- AMP, R, ROi and p have the same meanings as above,

- RO₂ is a group other than RO bonded to AMP by means of heteroatom and comprising at least two carbon atoms, and

- q is a positive integer.

More preferably still, the polymers correspond to the followin formulae (III) and (III)a:

in which:

- AMP, R, ROi, RO₂, p and q have the same meanings above,

- R₂ or R₃, which are identical or different, represent terminal group which can denote a hydrogen atom, an RO i H group, an R0₂H group, an AMP(OR)_p group or any mono functional group , such as alkyl, cycloalkyl, aryl, aralkyl, alkylaryl, alkyloxyalkyl, aryloxyalkyl or cycloalkoxyalkyl,

- a being a number greater than 1 and preferably greater than 2.

The aminoplast residues carrying their OR groups incorporated in the po lymers can be chosen without limitation from the fo llowing structures ( 1 ) to ( 12) :

in which:

- R has the same meaning as above,

- Ri denotes C1-C4 alkyl,

- y is a number at least equal to 2,

- x denotes 0 or 1.

Preferably, the aminoplast residue or residues carrying their OR groups are chosen from those with the following structure (13):

in which R, p and x have the same meanings as above.

The divalent alkyleneoxy residues are preferably those corresponding to the diols with the following general formula (14):

HO-(ZO)_y-(Zi(Z₂0)_w)t-(ZO)_y.-Z₃OH (14),

- y and y' being numbers ranging from 0 to 1000,

- t and w being numbers ranging from 0 to 10,

- Z, Z', Z₂ and Z3 being C₂-C₄ alkylene radicals and preferably -CH₂-CH(Z₄)- and -CH₂-CH(Z₄)-CH₂- radicals,

- Zi being an aromatic or nonaromatic, branched or unbranched, linear or cyclic radical comprising or not comprising one or more heteroatoms and having from 1 to 40 carbon atoms,

- Z₄ denoting a hydrogen atom or a C1-C4 alkyl radical or a Ci- C3 acyl radical, it being understood that at least one of the Z₄ radicals of the Z, Z', Z₂ and Z3 radicals is other than an acyl radical.

Preferably, Z₄ denotes a hydrogen atom or a methyl radical. More preferably still, t = 0 and Z, Z ' and Z₃ denote -CH₂CH₂- and at least one of y or y' is other than 0. The compounds of formula ( 14) are then polyethylene glyco ls.

The aminoplast ether polymers of formula (g) comprise at least one saturated or unsaturated and linear or cyclic chain comprising at least 8 carbon atoms and are described in particular in Patent US 5 914 373 , to which reference may be made for further details.

Mention may in particular be made, as polymers comprising an aminoplast ether backbone of formula (g), of the products Pure-Thix® L [PEG- 1 80/Octoxynol-40/TMMG Copolymer (INCI name)] , Pure- Thix M® [PEG- 1 80/Laureth-50/TMMG Copolymer (INCI name)] , Pure-Thix® HH [Polyether- 1 (INCI name)] ; Pure-Thix TX- 1442® [PEG- 1 8/dodoxynol-5/PEG-25 tristyrylphenol/tetramethoxymethyl- glyco luril copolymer] , which are provided by Sud-Chemie.

The thickening polymers participating as ingredient in the dispersion according to the invention can also be chosen from associative po lymers comprising at least one monomer comprising ethylenic unsaturations and comprising a sulpho group, in the free or partially or completely neutralized form, and comprising at least one hydrophobic part.

Preferably, the said polymers are partially or completely neutralized by an inorganic base (sodium hydroxide, potassium hydroxide, aqueous ammonia) or an organic base, such as mono-, di- or triethanolamine, an aminomethylpropanedio l, N-methylglucamine, basic amino acids, such as arginine and lysine, and the mixtures of these compounds.

These associative po lymers may or may not be crosslinked and are preferably crosslinked polymers, the crosslinking agents in this case originating from at least one monomer having at least two ethylenic unsaturations (carbon-carbon double bond).

The crosslinking monomers having at least two ethylenic unsaturations are chosen, for example, from diallyl ether, triallyl cyanurate, diallyl maleate, allyl (meth)acrylate, dipropylene glyco l diallyl ether, polyglycol diallyl ethers, triethylene glycol divinyl ether, hydroquinone diallyl ether, tetraallyloxyethane, tetra- or diethylene glycol di(meth)acrylate, triallylamine, tetraallylethylene- diamine, trimethylolpropane diallyl ether, trimethylo lpropane triacrylate, methylenebis(meth)acrylamide or divinylbenzene, allyl ethers of alcoho ls o f the sugar series or other allyl or vinyl ethers o f polyfunctional alcoho ls, and also allyl esters of phosphoric and/or vinylpho sphonic acid derivatives, or the mixtures of these compounds .

Use is more particularly made of methylenebisacrylamide, allyl methacrylate or trimethylo lpropane triacrylate. The degree of crosslinking generally varies from 0.01 to 10 mo l%, with respect to the po lymer.

The monomers comprising ethylenic unsaturation and comprising a sulpho group are chosen in particular from vinylsulphonic acid, styrenesulphonic acid, (meth)acrylamido(C i - C22)alkylsulphonic acids, N-(C i - C 22)alkyl(meth)acrylamido(C i - C22)alkylsulphonic acids, such as undecylacrylamidomethanesulphonic acid, and their partially or completely neutralized forms.

More particularly, use may be made o f (meth)acrylamido(C i - C22)alkylsulphonic acids, such as, for example, acrylamidomethanesulphonic acid, acrylamidoethanesulphonic acid, acrylamidopropanesulphonic acid, 2-acrylamido-2-methylpropane- sulphonic acid, methacrylamido-2-methylpropanesulphonic acid, 2- acrylamido-n-butanesulphonic acid, 2 -aery lamido -2,4,4 -trimethyl- pentanesulphonic acid, 2-methacrylamidododecylsulphonic acid, 2- acrylamido-2,6-dimethyl-3 -heptanesulphonic acid and their partially or completely neutralized forms .

Use is preferably made o f 2-acrylamido-2-methylpropane- sulphonic acid (AMPS) and its partially or completely neutralized forms.

The amphiphilic polymers present in the dispersion (A) according to the invention can also be chosen from random amphiphilic polymers of AMPS which are modified by reaction with a mono(C₆ - C22 n-alkyl)amine or di(C₆ - C22 n-alkyl)amine, such as those described in Application WO 00/3 1 154. The hydrophobic monomers which constitute the hydrophobic part of the polymer are preferably chosen from acrylates or acrylamides of fo llowing formula (k) :

in which Ri and R₃ , which are identical or different, denote a hydrogen atom or a linear or branched C i -C₆ alkyl radical (preferably methyl); Y denotes O or NH; R₂ denotes a hydrophobic hydrocarbon radical as defined above; x denotes a number of moles of alkylene oxide and varies from 0 to 100.

The R₂ radical is advantageously chosen from linear C₆ - C i 8 alkyl radicals (for example n-hexyl, n-octyl, n-decyl, n-hexadecyl or n-dodecyl), branched C₆ - C i 8 alkyl radicals or cyclic C₆ - C i 8 alkyl radicals (for example cyclododecane (C _{1 2}) or adamantane (C _{1 0})); C₆- C i 8 perfluoroalkyl radicals (for example the group of formula -(CH₂)₂- (CF₂)₉-CF₃) ; the cho lesteryl (C₂₇) radical or a cholesterol ester residue, such as the cholesteryl oxyhexanoate group; polycyclic aromatic groups, such as naphthalene or pyrene. Preference is more particularly given, among these radicals, to linear alkyl radicals and more particularly the n-dodecyl radical.

According to a specific form o f the invention, the monomer of formula (k) comprises at least one alkylene oxide unit (x > 1 ) and preferably a polyoxyalkylene chain. The polyoxyalkylene chain is preferably composed of ethylene oxide units and/or of propylene oxide units and more particularly still is composed of ethylene oxide units. The number of oxyalkylene units generally varies from 3 to 100, more preferably from 3 to 50 and more preferably still from 7 to 25.

The copolymers can also comprise other hydrophilic ethylenically unsaturated monomers chosen, for example, from (meth)acrylic acids, their β-substituted alkyl derivatives or their esters obtained with monoalcoho ls or mono- or polyalkylene glyco ls, (meth)acrylamides, vinylpyrrolidone, maleic anhydride, itaconic acid or maleic acid or the mixtures of these compounds.

These copolymers are described in particular in the documents EP 750 899, US 5 089578 and the following publications by Yotaro Morishima: "Self-assembling amphiphilic polyelectrolytes and their nanostructures - Chinese Journal of Polymer Science, Vol. 18, No. 40, (2000), 323-336"; "Micelle formation of random copolymers of sodium 2-(acrylamido)-2-methylpropanesulfonate and a non-ionic surfactant macromonomer in water as studied by fluorescence and dynamic light scattering - Macromolecules, 2000, Vol. 33, No. 10, 3694-3704"; "Solution properties of micelle networks formed by non- ionic moieties covalently bonded to a polyelectrolyte; salt effects on rheological behaviour - Langmuir, 2000, Vol. 16, No. 12, 5324-5332"; "Stimuli responsive amphiphilic copolymers of sodium 2- (acrylamido)-2-methylpropanesulfonate and associative macromonomers - Polym. Preprint, Div. Polym. Chem., 1999, 40(2), 220-221".

The distribution of the monomers in the copolymer can be random or blockwise.

Mention may more especially be made, among these polymers of this type, of:

- crosslinked or noncrosslinked and neutralized or nonneutralized copolymers comprising from 15 to 60% by weight of AMPS units and from 40 to 85% by weight of (C₈- Ci6)alkyl(meth)acrylamide units or of (C8-Ci₆)alkyl (meth)acrylate units, with respect to the polymer, such as those described in Application EP-A 750 899;

- terpolymers comprising from 10 to 90 mol% of acrylamide units, from 0.1 to 10 mol% of AMPS units and from 5 to 80 mol% of n-(C6-Ci8)alkylacrylamide units, such as those described in Patent US- 5 089578;

- copolymers of completely neutralized AMPS and of dodecyl methacrylate and also copolymers of AMPS and of n- dodecylmethacrylamide which may or may not be crosslinked, such as those described in the abovementioned papers by Morishima.

Mention will more particularly be made of the copolymers composed o f AMP S units o f fo llowing formula (XXX) :

in which X⁺ has the same definition as above,

in which x denotes an integer varying from 3 to 1 00, preferably from 5 to 80 and more preferably from 7 to 25 ; Ri has the same meaning as that indicated above in the formula (j ) and R₄ denotes a linear or branched C6-C22 and more preferably C 10-C22 alkyl .

The po lymers which are particularly preferred are those for which x = 25 , Ri denotes methyl and R₄ represents n-dodecyl; they are described in the abovementioned papers by Morishima.

The po lymers for which X⁺ denotes sodium or ammonium are more particularly preferred.

The po lymers o f the Genapol® range from Ho echst/Clariant can be employed in the dispersion according to the invention.

The thickening agent as defined above is preferably present in the dispersion (A) in a total content ranging from 0.01 to 10% by weight, with respect to the total weight of the dispersion (A) , preferably ranging from 0. 1 to 5 % by weight.

The direct emulsion (B) is an oil-in-water emulsion, i . e . with a fatty phase dispersed in an aqueous phase .

Preferably, the direct emulsion (B) comprises from 5 to 50% by weight, better still from 10 to 30%> by weight, with respect to the total weight of the emulsion (B), of one or more oils not comprising a carboxylic acid functional group .

According to the present invention, the emulsion (B) comprises one or more oxidizing agents .

This oxidizing agent can be chosen from the oxidizing agents conventionally used for the oxidation dyeing and bleaching of keratinous fibres, among which may be mentioned hydrogen peroxide, urea hydrogen peroxide, alkali metal bromates or ferricyanides, or peroxygenated salts, such as, for example, alkali metal or alkaline earth metal, such as sodium, potassium or magnesium, persulphates, perborates and percarbonates. Use may also be made, as oxidizing agent, of one or more oxidation/reduction enzymes, such as laccases, peroxidases and 2-electron oxidoreductases (such as uricase), optionally in the presence of their respective donor or cofactor.

The use of hydrogen peroxide is particularly preferred. The latter can advantageously be employed in aqueous solution (aqueous hydrogen peroxide solution), the concentration of which can vary more particularly from 0. 1 to 50% by weight, more preferentially still from 0.5 to 20% by weight and better still from 1 to 1 5 % by weight, with respect to the total weight of the emulsion (B) .

Depending on the degree of bleaching desired, the oxidizing agent can also comprise one or more compounds preferably chosen from peroxygenated salts .

Preferably, the pH of the emulsion (B) is less than 7. This pH can be adjusted to the desired value by the use o f one or more acidifying agents which can in particular be chosen from those described above.

The emulsion (B) of use in the present invention additionally comprises one or more surfactants. These surfactants are, for example, anionic, nonionic, cationic and amphoteric surfactants .

The surfactants present in the emulsion (B) are chosen whatever their HLB value. The term HLB (Hydrophilic-Lipophilic Balance) is well known to a person skilled in the art and denotes the hydrophilic-lipophilic balance of a surfactant.

The HLB or hydrophilic-lipophilic balance of the surfactant or surfactants used according to the invention is the HLB according to Griffin defined in the publication J. Soc . Cosm. Chem. , 1954 (Volume 5), pages 249-256.

Nonlimiting examp les o f surfactants are given in particular in the work entitled McCutcheon' s Emulsifiers & Detergents, 1998 International Edition, MC Publishing Company, in the chapter HLB Index.

Preferably, the emulsion (B) comprises one or more nonionic or anionic surfactants.

The anionic surfactants are more especially chosen from the salts, in particular salts o f alkali metals, especially of sodium, ammonium salts, amine salts, such as amino alcoho l salts, or salts of alkaline earth metals, such as magnesium, o f the fo llowing compounds :

- alkyl sulphates, alkyl ether sulphates, alkylamido ether sulphates, alkylaryl polyether sulphates or monoglyceride sulphates;

- alkylsulphonates, alkylamidesulphonates, alkylarylsulphonates, a-o lefinsulphonates or paraffinsulphonates;

- alkyl phosphates or alkyl ether phosphates;

- alkyl sulpho succinates, alkyl ether sulphosuccinates or alkylamide sulphosuccinates;

- alkyl sulphosuccinamates;

- alkyl sulphoacetates;

- acylsarcosinates, acylisethionates and N-acyltaurates;

- salts of fatty acids, such as oleic acid, ricinoleic acid, palmitic acid, stearic acid, coconut oil acid or hydrogenated coconut oil acid;

- salts of alkyl-D-galactosideuronic acids;

- acyl lactylates;

- salts of polyoxyalkylenated alkyl ether carboxylic acids, polyoxyalkylenated alkylaryl ether carboxylic acids or polyoxyalkylenated alkylamido ether carboxylic acids, in particular those comprising from 2 to 50 ethylene oxide groups;

- and their mixtures.

It should be noted that the alkyl or acyl radical o f these different compounds advantageously comprises from 6 to 24 carbon atoms, preferably from 8 to 24 carbon atoms, and the aryl radical preferably denotes a phenyl or benzyl group .

The nonionic surfactants are more particularly chosen from mono- or polyoxyalkylenated nonionic surfactants and mono- or polyglycerolated nonionic surfactants . The oxyalkylene units are more particularly oxyethylene or oxypropylene units, or their combination, preferably oxyethylene units.

Mention may be made, as examples of oxyalkylenated nonionic surfactants, of:

- oxyalkylenated (Cs- C 24)alkylphenols,

- oxyalkylenated, saturated or unsaturated, linear or branched, C 8 - C30 alcoho ls,

- oxyalkylenated, saturated or unsaturated, linear or branched, C 8 - C30 amides,

- esters of saturated or unsaturated and linear or branched C₈ - C30 acids and of po lyethylene glyco ls,

- esters of saturated or unsaturated and linear or branched C₈ - C30 acids and of sorbito l which are po lyoxyethylenated,

- oxyethylenated, saturated or unsaturated, vegetable oils,

- condensates of ethylene oxide and/or of propylene oxide,

- and their mixtures.

These surfactants exhibit a number of moles o f ethylene oxide and/or of propylene oxide of between 1 and 1 00, preferably between 2 and 50.

In a preferred alternative form, the emulsion (B) comprises one or more nonionic surfactants . In this alternative form, this nonionic surfactant or these nonionic surfactants are preferably oxyalkylenated or polyglycero lated and more preferably still oxyalkylenated. In accordance with a preferred embodiment of the invention, the oxyalkylenated nonionic surfactants are chosen from oxyethylenated C8-C30 alcohols and esters of C8-C30 acids and of polyethylene glycols.

Mention may be made, among oxyalkylenated nonionic surfactants, without implied limitation, of the compounds belonging to the following families:

- oxyethylenated alkylphenols,

- EO/PO condensates,

- oxyethylenated vegetable oils,

- oxyethylenated fatty alcohols,

- esters of fatty acids and of polyethylene glycols,

- esters of fatty acids and of sorbitol which are polyoxyethylenated.

Mention may be made, as commercial compounds, of:

- Prox-Onic EP 4060-1 (HLB = 1) Protex

- Synperonic PE L101 (HLB = 1) ICI

- Etocas 29 (HLB = 1.7) Croda

- Genapol PF 10(HLB=2) Hoechst

- Synperonic PE L81 (HLB=2) ICI

- Prox-Onic EP 1090-1 (HLB=3) Protex

- Sinnopal DPN2 (HLB=3.3) Henkel

- Antarox CA 210 (HLB=3.5) Rhone-Poulenc

- Alkasurf OPll (HLB=3.6) Rhone-Poulenc

- Triton X15 (HLB=3.6) Rohm & Haas

- Alkasurf OP1 (HLB=3.6) Rhone-Poulenc

- Arlacel 121 (HLB=3.8) ICI

- Prox-Onic HR or HRH-05 (HLB=3.8) Protex

- Etocas 5 (HLB=3.9) Hoechst

- Genapol PF20 (HLB=4) Hoechst

- Imbentin N/7 A (HLB=4) Kolb

- Synperonic PE L122 (HLB=4) ICI

- Ethylan NP1 (HLB=4.5) Harcros - Imbentin N/020 (HLB=4.5) Kolb

- Kotilen O/3/020 (HLB=4.5) Kolb

- Synperonic PE L31 (HLB=4.5) ICI

- TO-55-A(HLB=4.5) Hefti

- Alkasurf NP-1 (HLB=4.6) Rhone-Poulenc

- Antarox CO 210 (HLB=4.6) Rhone-Poulenc

- Prox-Onic NP-1 (HLB=4.6) Protex

- Rhodiasurf NP2(HLB=4.6) Rhone-Poulenc

- Soprophor BC2 (HLB=4.6) Rhone-Poulenc

- Triton N17(HLB=4.6) Rohm & Haas

- Akyporox NP 15 (HLB=4.7) Chem-Y

- Texofor M2(HLB=4.8) Rhone-Poulenc

- Alkasurf SA2 (HLB=4.9) Rhone-Poulenc

- Arlacel 989 (HLB=4.9) ICI

- Brij 72(HLB=4.9) ICI

- Brij 92(HLB=4.9) ICI

- Brij 93(HLB=4.9) ICI

- Prox-Onic SA-1 or 2/02 (HLB=4.9) Protex

- Simulsol 72(HLB=4.9) SEPPIC

- Simulsol 92(HLB=4.9) SEPPIC

- Volpo S-2 (HLB=4.9) Croda

- Arlacel 581 (HLB=5.0) ICI

- Arlacel 582 (HLB=5.0) ICI

- Genapol O-020 (HLB=5.0) Hoechst

- Imbentin POA/020 (HLB=5.0) Kolb

- Mergital Q2 (HLB=5.0) Henkel

Imbentin POA/024 (HLB=5.5) (ICI)

Synperonic PE L92 (HLB= 5.5)(ICI)

Mergital LM2 (HLB=5.8) (Henkel)

Atlas G-70140(HLB=6) (ICI)

Imbentin. AG/124S/ 020 (HLB=6) (Kolb) Imbentin. L/125/025(HLB=6) (Kolb)

Simulsol 989 (HLB=6) (SEPPIC)

Soprophor HR10 (HLB=6) (Rhone-Poulenc) Kotilen O/1/050 (HLB=6.2) (Kolb)

Croduret 10 (HLB=6.3) (Croda)

Etocas 10(HLB=6.3) (Croda)

Imbentin OA/030 (HLB=6.3) (Kolb)

Soprophor 208 (HLB=6.9) (Rhone-Poulenc) Ethylan 172 (HLB=7) (Harcros)

Akyporox NP 40 (HLB=7.1) (Chem-Y) Polychol 5(HLB=7.3) (Croda)

Arlatone 985 (HLB=7.5) (ICI

Sandoxylate FOL4(HLB=7.5) (Sandoz) Radiasurf 7453 (HLB=7.8) (Oleofina)

Prox-onic OA-1/04 (HLB=7.9) (Protex) Prox-onic TD-1/03 (HLB=7.9) (Protex) Genapol PF 40 (HLB = 8) (Hoechst)

PGE-400 - DS(HLB = 8) (Hefti)

PGE-400- DO (HLB = 8) (Hefti)

Sapogenat 6-040 (HLB=8) (Hoechst)

Intrasol FA28/50/4 (HLB = 8.1) (Stockhausen) Serdox NOG 200 S (HLB=8.5) (Servo) Berol 26(HLB=8.9) (Berol Nobel)

Genapol O-050 (HLB=9) (Hoechst)

Prox-onic LA-1/04 (HLB=9.2) (Protex) Eumulgin 05 (HLB=9.5) (Henkel)

Etocas 20(HLB=9.6) (Croda)

Antarox CO 520 (HLB = 10) (Rhone-Poulenc) Imbentin POA/060 (HLB = 10) (Kolb)

TO-55-EL (HLB = 10) (Hefti)

Atlas G-1086 (HLB = 10.2) (ICI)

Atlox 4878B (HLB = 10.5) (ICI)

Berol 059 (HLB=10.5) (Berol Nobel)

Kessco PEG 600 Dilaurate (HLB = 10.5) (Akzo Mergital LT6 (HLB = 10.6) (Henkel)

Polychol 10 (HLB = 10.7) (Croda)

Prox-onic HR-025 (HLB = 10.8) (Protex) Tebenal NP6 (HLB = 10.9) (Bohme)

Cremophor A6(HLB = 11) (BASF)

Genapol O-080 (HLB = 11) (Hoechst)

Genapol T-080 (HLB=11) (Hoechst)

Kotilen- 0/3(HLB = ll) (Kolb)

Lutensol AP 7 (HLB = 11) (BASF)

Tween 85(HLB = 11) (ICI)

Tebecid S8 (HLB=11.2) (Bohme)

Berol 047 (HLB = 11.4) (Berol Nobel)

Soprophor 860P (HLB = 11.4) (Rhone-Poulenc) Dobanol 45-7(HLB = l 1.6) (Shell)

Prox-onic HR-030 (HLB = 11.7) (Protex) Ethonic 1214-6.5 (HLB = 11.8) (Ethyl)

Prox-onic OA-1/09 (HLB = 11.9) (Protex) Cremophor S9(HLB = 12) (BASF)

Imbentin AG/128/ 080(HLB = 12) (Kolb) Serdox NOG 440 (HLB = 12) (Servo)

Softanol 70(HLB = 12.1) (BP Chemicals) Renex 707 (HLB = 12.2) (ICI)

Simulsol 830 NP (HLB = 12.3) (SEPPIC) Brij 76 (HLB = 12.4) (ICI)

Tebenal T10 (HLB = 12.4) (Bohme)

Volpo S-10(HLB = 12.4) (Croda)

Eumulgin O10 (HLB = 12.5) (Henkel)

Berol 199 (HLB=12.6) (Berol Nobel)

Triton N-87 (HLB 12.6) (Rohm & Haas) Polychol 15 (HLB = 12.7) (Croda)

Brij 56 (HLB = 12.9) (ICI)

Simulsol 56 (HLB = 12.9) (SEPPIC)

Cremophor All (HLB = 13) (BASF)

Eumulgin 286 (HLB = 13) (Henkel)

Genapol T-110 (HLB=13) (Hoechst)

Sandoxylate FOL12 (HLB = 13) (Sandoz) Bio soft HR 40 (HLB = 13.1) (Stepan) Berol 046 (HLB=13.5) (Berol Nobel)

Eumulgin Bl (HLB = 13.5) (Henkel)

Dobanol 45-11 (HLB = 13.7) (Shell)

Aqualose W20(HLB = 14) (Westbrock Lanolin) Ethylan DP (HLB = 14) (Harcros)

Mergital OC12 (HLB = 14) (Henkel)

Simulsol 1230 NP (HLB = 14) (SEPPIC) Tagat Rl (HLB = 14) (Goldschmidt)

Tagat I 2 (HLB = 14.2) (Goldschmidt)

Tebecid RM20(HLB=14.4) (Bohme)

Imbentin AG/168/150 (HLB = 14.5) (Kolb) Prox-onic LA-1/012 (HLB = 14.5) (Protex) Etocas 60(HLB = 14.7) (Croda)

Radiasurf 7157 (HLB=14.9) (Oleofina) Genapol T-180 (HLB=15) (Hoechst)

Montanox 80 (HLB = 15) (SEPPIC)

Serdox NJAD 20 (HLB = 15) (Servo)

Tagat R60 (HLB = 15) (Goldschmidt)

Berol 278 (HLB=15.2) (Berol Nobel)

Brij 78 (HLB = 15.3) (ICI)

Simulsol 98 (HLB = 15.3) (SEPPIC)

Montanox 40 (HLB 15.6) (SEPPIC)

Brij 58 (HLB = 15.7) (ICI)

Aqualose L75 (HLB = 16) (Westbrock Lanolin) Atlas G-1471 (HLB=16) (ICI)

Berol 281 (HLB=16) (Berol Nobel)

Berol 292 (HLB=16) (Berol Nobel)

Nafolox 20-2230OE (HLB = 16) (Condea) Genapol C-200 (HLB=16) (Hoechst)

Myrj 51 (HLB = 16) (ICI)

Simulsol PS 20(HLB = 16) (SEPPIC)

Tergitol 15 S 20 (HLB 16.3) (Union Carbide) Synperonic PE P75 (HLB = 16.5) (ICI)

Montanox 20 (HLB = 16.7) (SEPPIC) Myrjj 52(HLB = 16.9) (ICI)

Simulsol 3030 NP (HLB = 17) (SEPPIC)

Imbentin AG/168/400 (HLB = 17.5) (Kolb)

Rhodia Surf NP40 (HLB = 17.7) (Rhone-Poulenc)

Incropol CS-50 (HLB = 17.9) (Croda)

Servirox OEG 90/50 (HLB = 18) (Servo)

Prox-onic HR-0200 (HLB = 18.1) (Protex)

Berol 243 (HLB=18.2) (Berol Nobel)

Imbentin N/600 (HLB = 18.5) (Kolb)

Antarox CO 980 (HLB = 18.7) (Rhone-Poulenc)

Antarox CO 987 (HLB = 18.7) (Rhone-Poulenc)

Berol 08(HLB=18.7) (Berol Nobel)

Brij 700 (HLB = 18.8) (ICI)

Prox-onic NP-0100 (HLB = 19) (Protex)

Rs-55-100 (HLB = 19) (Hefti)

Imbentin AG/168S/950 (HLB=20) (Kolb)

Synperonic PE F87 (HLB=24) (ICI)

Alkasurf BA-PE80 (HLB=26.1) (Rhone-Poulenc)

Synperonic PE F38 (HLB=30.5) (ICI)

The concentration of these oxyalkylenated nonionic surfactants can vary from approximately 0.1 to 30%, preferably from approximately 0.5 to 25% and more preferably still from approximately 1 to 20% of the total weight of the emulsion (B) according to the invention.

The dispersion (A) and the emulsion (B) comprise one or more oils not comprising a carboxylic acid functional group.

The term "oils" is understood to mean an organic compound which is insoluble in water at normal temperature (25°C) and at atmospheric pressure (760 mmHg; i.e. 1.013 x 10⁵ Pa) (solubility in water of less than 5%> by weight, preferably of less than 1%> by weight and more preferably still of less than 0.1% by weight). These compounds exhibit, in their structure, at least one hydrocarbon chain comprising at least 6 carbon atoms or a sequence of at least two siloxane groups. In addition, the oils are soluble in organic solvents under the same temperature and pressure conditions, such as, for example, chloroform, ethanol or benzene. Furthermore, the oils are liquid at normal temperature (25 °C) and at atmospheric pressure (760 mmHg; i.e. 1 .013 x 10⁵ Pa) .

The term "oil not comprising a carboxylic acid functional group" denotes an oil not comprising a -COOH or -COO group .

According to a preferred form o f the invention, the oil or oils not comprising a carboxylic acid functional group used in the dispersion (A) and in the emulsion (B), which are identical or different, can be chosen in particular from hydrocarbons, non-silicone oils o f animal, vegetable, mineral or synthetic origin, fatty alcohols, fatty acid and/or fatty alcoho l esters, silicones, and their mixtures.

It is specified that, within the meaning of the invention, the fatty alcohols and fatty acids, present in particular in the esters, more particularly exhibit one or more saturated or unsaturated and linear or branched hydrocarbon groups comprising from 6 to 30 carbon atoms which are optionally substituted, in particular by one or more hydroxyl groups (in particular from 1 to 4) . If they are unsaturated, these compounds can comprise from 1 to 3 conjugated or nonconjugated carbon-carbon double bonds.

More particularly, the liquid hydrocarbons are chosen from:

- linear or branched and optionally cyclic lower C₆ - C i 6 alkanes . Mention may be made, by way o f examp le, o f hexane, undecane, dodecane, tridecane or isoparaffins, such as isohexadecane, isododecane and isodecane,

- linear or branched hydrocarbons of mineral, animal or synthetic origin of more than 16 carbon atoms, such as liquid paraffins, liquid petrolatum, polydecenes, hydrogenated polyisobutene, such as Parleam^®, or squalane.

In a preferred alternative form, the liquid hydrocarbon or hydrocarbons are chosen from liquid paraffins and liquid petrolatum.

Preferably, the silicone is chosen from liquid polydialkylsiloxanes, in particular liquid polydimethylsiloxanes (PDMSs), and liquid polyorganosiloxanes comprising at least one aryl group .

These silicones can also be organomodified. The organomodified silicones which can be used in accordance with the invention are liquid silicones as defined above which comprise, in their structure, one or more organofunctional groups attached via a hydrocarbon group .

The organopolysiloxanes are defined in more detail in the work by Walter Noll, " Chemistry and Technology of Silicones" ( 1968), Academic Press. They can be vo latile or nonvo latile.

When they are volatile, the silicones are chosen more particularly from those having a boiling point of between 60°C and 260°C and more particularly still from:

cyclic po lydialkylsiloxanes comprising from 3 to 7 and preferably from 4 to 5 silicon atoms. They are, for example, octamethylcyclotetrasiloxane, sold in particular under the name of Volatile Silicone^® 7207 by Union Carbide or Silbione^® 70045 V2 by Rhodia, decamethylcyclopentasiloxane, sold under the name of Volatile Silicone^® 7158 by Union Carbide and Silbione® 70045 V5 by Rhodia, dodecamethylcyclohexasiloxane, sold under the name of Silso ft 1217 by Momentive Performance Materials, and their mixtures.

Mention may also be made o f cyclocopolymers of the dimethylsiloxane/methylalkylsiloxane type, such as Silicone Vo latile^® FZ 3 1 09, sold by Union Carbide, of formula:

D" - D' D" - D'

CH CH₃ with D" : — Si - O— with D' : - Si - O—

CH₃ C₈H₁₇

Mention may also be made o f mixtures o f cyclic polydialkylsiloxanes with silicon-derived organic compounds, such as the mixture of octamethylcyclotetrasiloxane and of tetratrimethylsilylpentaerythrito l (50/50) and the mixture of octamethylcyclotetrasiloxane and of l,l'-oxy(2,2,2',2',3,3'- hexatrimethylsilyloxy)bisneopentane;

volatile linear polydialkylsiloxanes having from 2 to 9 silicon atoms and exhibiting a viscosity of less than or equal to 5 x 10^~6 m²/s at 25°C. They are, for example, decamethyltetrasiloxane, sold in particular under the name "SH 200" by Toray Silicone. Silicones coming within this category are also described in the article published in Cosmetics and Toiletries, Vol.91, Jan.76, pp.27-32, Todd & Byers, "Volatile Silicone Fluids for Cosmetics". The viscosity of the silicones is measured at 25°C according to Standard ASTM 445, Appendix C.

Use may also be made of nonvolatile polydialkylsiloxanes.

These nonvolatile silicones are chosen more particularly from polydialkylsiloxanes, among which may be mentioned mainly polydimethylsiloxanes possessing trimethylsilyl end groups.

Mention may be made, among these polydialkylsiloxanes, without implied limitation, of the following commercial products:

- Silbione® oils of the 47 and 70047 series or Mirasil® oils sold by Rhodia, such as, for example, the oil 70047 V 500000;

- oils of the Mirasil® series sold by Rhodia;

- oils of the 200 series from Dow Corning, such as DC200 having a viscosity of 60000 mm²/s;

- Viscasil® oils from General Electric and some oils of the SF series (SF 96, SF 18) from General Electric.

Mention may also be made of polydimethylsiloxanes possessing dimethylsilanol end groups known under the name of dimethiconol (CTFA), such as oils of the 48 series from Rhodia.

The silicones possessing aryl groups include polydiarylsiloxanes, in particular polydiphenylsiloxanes, and polyalkylarylsiloxanes. Mention may be made, by way of example, of the products sold under the following names:

. Silbione® oils of the 70641 series from Rhodia;

. oils of the Rhodorsil® 70633 and 763 series from Rhodia; . the oil Dow Corning 556 Cosmetic Grade Fluid from Dow Corning;

. silicones of the PK series from Bayer, such as the product

PK20;

. some oils of the SF series from General Electric, such as

SF 1023, SF 1154, SF 1250 and SF 1265.

The liquid fatty esters are preferably liquid esters of saturated or unsaturated and linear or branched Ci-C₂₆ aliphatic mono- or polyacids and of saturated or unsaturated and linear or branched Ci-C₂6 aliphatic mono- or polyalcohols, the total number of carbon atoms in the esters being greater than or equal to 10.

Preferably, for the esters of monoalcohols, at least one of the alcohol or of the acid from which the esters of the invention result is branched.

Mention may be made, among monoesters of monoacids and of monoalcohols, of ethyl palmitate, isopropyl palmitate, alkyl myristates, such as isopropyl myristate or ethyl myristate, isocetyl stearate, 2-ethylhexyl isononanoate, isodecyl neopentanoate or isostearyl neopentanoate.

Use may also be made of esters of C₄-C₂₂ di- or tricarboxylic acids and of Ci-C₂₂ alcohols and esters of mono-, di- or tricarboxylic acids and of di-, tri-, tetra- or pentahydroxy C₄-C₂₆ nonsugar alcohols.

Mention may in particular be made of: diethyl sebacate; diisopropyl sebacate; di(2-ethylhexyl) sebacate; diisopropyl adipate; di(n-propyl) adipate; dioctyl adipate; di(2-ethylhexyl) adipate; diisostearyl adipate; di(2-ethylhexyl) maleate; triisopropyl citrate; triisocetyl citrate; triisostearyl citrate; glyceryl trilactate; glyceryl trioctanoate; trioctyldodecyl citrate; trioleyl citrate; neopentyl glycol diheptanoate; or diethylene glycol diisononanoate.

The composition can also comprise, as liquid fatty ester, esters and diesters of sugars and of C6-C30, preferably Ci₂-C₂₂, fatty acids. It should be remembered that the term "sugar" is understood to mean oxygen-comprising hydrocarbon compounds which have several alcohol functional groups, with or without aldehyde or ketone functional group, and which comprise at least 4 carbon atoms . These sugars can be monosaccharides, oligosaccharides or polysaccharides .

Mention may be made, as suitable sugars, for example, o f sucrose (or saccharose), glucose, galactose, ribose, fucose, maltose, fructose, mannose, arabinose, xylose, lactose and their derivatives, in particular alkyl derivatives, such as methyl derivatives, for example methylglucose.

The esters of sugars and of fatty acids can be chosen in particular from the group consisting o f the esters or mixtures of esters of sugars described above and o f saturated or unsaturated and linear or branched C6 - C30 , preferably C 1 2 - C22 , fatty acids . If they are unsaturated, these compounds can comprise from one to three conjugated or nonconjugated carbon-carbon double bonds.

The esters according to this alternative form can also be chosen from mono-, di-, tri- and tetraesters, polyesters and their mixtures.

These esters can, for example, be o leates, laurates, palmitates, myristates, behenates, cocoates, stearates, linoleates, linolenates, caprates, arachidonates or their mixtures, such as, in particular, mixed oleate/palmitate, oleate/stearate or palmitate/stearate esters .

More particularly, use is made of mono- and diesters and in particular of sucrose, glucose or methylglucose mono- or dio leates, -stearates, -behenates, -o leate/palmitates, -lino leates, -lino lenates or -oleate/stearates .

Mention may be made, by way o f example, of the product sold under the name Glucate® DO by Amerchol, which is a methylglucose dio leate.

Finally, use may also be made of natural or synthetic esters o f mono-, di- or triacids with glycero l.

Mention may be made, among these, of vegetable oils.

Mention may be made, as oils o f vegetable origin or synthetic triglycerides which can be used in the composition o f the invention as liquid fatty esters, for example, of triglyceride oils of vegetable or synthetic origin, such as liquid triglycerides of fatty acids comprising from 6 to 30 carbon atoms, such as triglycerides of heptanoic or octanoic acids, or also, for example, sunflower, maize, soybean, cucumber, grape seed, sesame, hazelnut, apricot, macadamia, arara, castor or avocado oils, triglycerides of caprylic/capric acids, such as those so ld by Stearineries Dubois or those so ld under the names Miglyo l^® 8 10, 8 12 and 8 1 8 by Dynamit Nobel, jojoba oil or shea butter oil.

Use will preferably be made, as esters according to the invention, o f liquid fatty esters resulting from monoalcoho ls. These liquid fatty alcoho ls can be unsaturated.

Isopropyl myristate or isopropyl palmitate are particularly preferred.

Preferably, the liquid fatty alcoho ls o f the invention comprise from 8 to 30 carbon atoms.

The liquid fatty alcoho ls can be unsaturated.

These liquid unsaturated fatty alcoho ls exhibit, in their structure, at least one double or triple bond. Preferably, the fatty alcoho ls o f the invention have, in their structure, one or more double bonds . When several double bonds are present, they are preferably 2 or 3 in number and they may or may not be conjugated.

These fatty alcoho ls can be linear or branched.

They can optionally comprise, in their structure, at least one aromatic or nonaromatic ring. Preferably, they are acyclic.

More particularly, the liquid unsaturated fatty alcoho ls o f the invention are chosen from o leyl alcoho l, lino leyl alcoho l, lino lenyl alcoho l or undecylenyl alcoho l.

Oleyl alcoho l is very particularly preferred.

The liquid fatty alcoho ls can also be saturated branched fatty alcoho ls. More particularly, the liquid saturated branched fatty alcoho ls o f the invention are chosen from iso stearyl alcoho l and octyldodecanol.

Preferably, the oil or oils not comprising a carboxylic acid functional group used in the dispersion (A) and/or the emulsion (B) do not comprise oxyalkylene units or glycerol units. Preferably, the oil or oils not comprising a carboxylic acid functional group used in the dispersion (A) and/or the emulsion (B) are nonsilicone oils.

According to a preferred embodiment, the oil or oils not comprising a carboxylic acid functional group used in the dispersion

(A) and/or the emulsion (B) are chosen from hydrocarbons, nonsilicone oils o f animal, vegetable, mineral or synthetic origin, fatty alcoho ls, fatty acid and/or fatty alcoho l esters, silicones and their mixtures; preferably from liquid petrolatum, polydecenes, liquid esters of fatty acids and/or of fatty alcoho ls, liquid fatty alcoho ls and their mixtures; and more preferably from liquid petrolatum, polydecenes, liquid fatty alcoho ls and their mixtures.

More preferably still, the oil not comprising a carboxylic acid functional group is liquid petrolatum.

The mixture of the dispersion (A) and of the direct emulsion

(B) comprises an amount of oil not comprising a carboxylic acid functional group of at least 20% by weight, preferably of between 20.5 and 75 % by weight, with respect to the total weight of the said mixture, preferably of at least 25 % by weight, more particularly of between 25.5 and 75 % by weight, and more preferably of at least 30% by weight. According to a specific embodiment, the mixture comprises between 30.5 and 75 % by weight of oil not comprising a carboxylic acid functional group, with respect to the total weight of the said mixture.

The dispersion (A) and/or the direct emulsion (B) can additionally comprise one or more additional fatty substances other than the oils not comprising a carboxylic acid functional group defined above, such as, in particular, solid fatty alcoho ls, such as cetyl alcoho l, stearyl alcohol or their mixtures . These additional fatty substances are devoid of carboxylic acid functional group .

Advantageously, the dispersion (A) is provided in the form o f a gel or of a cream.

Advantageously, the emulsion (B) is provided in the form of a so lution, o f an emulsion or of a gel. According to a first embodiment of the invention, the dispersion (A) additionally comprises one or more oxidation dyes .

In this case, the agent according to the invention is used for the oxidation dyeing o f keratinous fibres.

The oxidation dyes which can be used in the present invention are generally chosen from oxidation bases, optionally in combination with one or more couplers .

The oxidation bases can be chosen in particular from para- phenylene diamines, bisphenylalkylenediamines, para-aminophenols, ortho-aminopheno ls, heterocyclic bases and their addition salts .

Mention may be made, among para-phenylenediamines, by way of example, of para-phenylenediamine, para-toluylenediamine, 2- chloro-para-phenylene diamine, 2,3 -dimethyl-para-phenylenediamine, 2,6-dimethyl-para-phenylenediamine, 2,6-diethyl-para-phenylene- diamine, 2,5 -dimethyl-para-phenylenediamine, N,N-dimethyl-para- phenylenediamine, Ν,Ν-diethyl-para-phenylenediamine, N,N-dipropyl- para-phenylenediamine, 4 - amino -N,N- diethyl- 3 -methylaniline, N,N- bis( -hydroxyethyl)-para-phenylenediamine, 4-N,N-bis( -hydroxy- ethyl)amino -2 -methylaniline, 4 -N,N-bis( -hydroxy ethyl) amino -2- chloro aniline, 2-( -hydroxyethyl)-para-phenylenediamine, 2-fluoro- para-phenylenediamine, 2-isopropyl-para-phenylenediamine, Ν-(β- hydroxypropyl) -para-phenylenediamine, 2-hydroxymethyl-para- phenylene diamine, N,N- dimethyl- 3 -methyl-para-phenylenedi amine, N,N-(ethyl, -hydroxyethyl)-para-phenylenediamine, Ν-(β,γ- dihydroxypropyl) -para-phenylenediamine, N- (4 '-amino phenyl) -para- phenylenediamine, N-phenyl-para-phenylenediamine, 2-(β- hydroxyethyloxy) -para-phenylenediamine, 2-( -acetylamino ethyloxy)- para-phenylene diamine, N-( -methoxy ethyl) -para-phenylenediamine, 4-aminophenylpyrrolidine, 2 -thienyl-para-phenylene diamine, 2-(β- hydroxyethylamino)-5 -aminotoluene, 3 -hydroxy- 1 -(4 '-amino - phenyl)pyrrolidine and their addition salts with an acid.

Among the para-phenylenediamines mentioned above, para- phenylenediamine, para-toluylenediamine, 2-isopropyl-para- phenylenediamine, 2-( -hydroxyethyl)-para-phenylenediamine, 2-(β- hydro xyethyloxy) -par a-phenylene diamine, 2, 6 -dimethyl-par a- phenylene diamine, 2,6-diethyl-para-phenylenediamine, 2, 3 -dimethyl- par a-phenylene diamine, N, N-bis( - hydroxy ethyl) -par a-phenylene- diamine, 2 -chloro -par a-phenylene diamine, 2-( -acetylaminoethyloxy)- para-phenylenediamine and their addition salts with an acid are particularly preferred.

Mention may be made, among bisphenylalkylenediamines, by way o f example, o f N,N'-bis( -hydroxyethyl)-N,N'-bis(4'- aminophenyl)- l ,3 -diaminopropanol, N,N'-bis( -hydroxyethyl)-N,N'- bis (4 '-aminophenyl) ethylene diamine, N,N'-bis(4-aminophenyl)tetra- methylene diamine, N, N'-bis( - hydroxy ethyl) -N,N'-bis(4- amino - phenyl)tetramethylenediamine, N,N'-bis(4-methylaminophenyl)tetra- methylenediamine, N,N'-bis(ethyl)-N,N'-bis(4'-amino-3 '- methylphenyl)ethylenediamine, 1 , 8-bis(2,5 -diaminophenoxy)-3 ,6- dioxaoctane and their addition salts.

Mention may be made, among para-aminophenols, by way of example, of para-aminophenol, 4-amino-3 -methylpheno l, 4-amino-3 - fluoropheno l, 4-amino-3 -chlorophenol, 4-amino-3 -(hydroxy- methyl)pheno l, 4-amino-2-methylpheno l, 4-amino-2- (hydroxymethyl)phenol, 4-amino-2-(methoxymethyl)phenol, 4-amino- 2-(aminomethyl)phenol, 4-amino -2- [(β-hydroxyethy l)aminomethyl] - pheno l, 4-amino-2-fluorophenol and their addition salts with an acid.

Mention may be made, among ortho-aminopheno ls, by way o f example, of 2-aminophenol, 2-amino-5 -methylpheno l, 2-amino-6- methylpheno l, 5 -acetamido-2-aminopheno l and their addition salts.

Mention may be made, among heterocyclic bases, by way o f example, of pyridine derivatives, pyrimidine derivatives and pyrazo le derivatives.

Mention may be made, among pyridine derivatives, o f the compounds described, for example, in Patents GB 1 026 978 and GB 1 153 196, such as 2,5 -diaminopyridine, 2- [(4-methoxy- phenyl)amino] -3 -aminopyridine, 3 ,4-diaminopyridine and their addition salts. Other pyridine oxidation bases of use in the present invention are the 3-aminopyrazolo[ 1 ,5-a]pyridine oxidation bases or their addition salts described, for example, in Patent Application FR 2801 308. Mention may be made, by way of example, of pyrazolo[ 1 ,5-a]pyridin-3-ylamine; 2-(acetylamino)pyrazolo[ 1 ,5- a]pyridin-3-ylamine; 2-(morpholin-4-yl)pyrazolo[ 1 ,5-a]pyridin-3- ylamine; 3-aminopyrazolo [ 1 ,5-a]pyridine-2-carboxylic acid; 2- methoxypyrazolo[ 1 ,5-a]pyridin-3-ylamine; (3-aminopyrazolo[ 1 ,5-a]- pyridin-7-yl)methanol; 2-(3-aminopyrazolo[ 1 ,5-a]pyridin-5-yl)ethanol; 2-(3-aminopyrazolo[ 1 ,5-a]pyridin-7-yl)ethanol; (3-aminopyrazolo[ 1 ,5- a]pyridin-2-yl)methanol; 3,6-diaminopyrazolo[ 1 ,5-a]pyridine; 3,4- diaminopyrazolo[ 1 ,5-a]pyridine; pyrazolo[l ,5-a]pyridine-3,7-diamine; 7-(morpholin-4-yl)pyrazolo [ 1 ,5-a]pyridin-3-ylamine; pyrazolo[ 1 ,5- a]pyridine-3, 5 -diamine; 5-(morpholin-4-yl)pyrazolo[l ,5-a]pyridin-3- ylamine; 2-[(3-aminopyrazolo[ 1 ,5-a]pyridin-5-yl)(2-hydroxy- ethyl)amino]ethanol; 2-[(3-aminopyrazolo[ 1 ,5-a]pyridin-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 their addition salts.

Mention may be made, among pyrimidine derivatives, of the compounds described, for example, in Patents DE 2359 399; JP 88-169571; JP 05-63124; EP 0770375 or Patent Application WO 96/15765, such as 2,4,5,6-tetraaminopyrimidine, 4-hydroxy-2,5,6- triaminopyrimidine, 2-hydroxy-4,5,6-triaminopyrimidine, 2,4- dihydroxy-5,6-diaminopyrimidine, 2,5,6-triaminopyrimidine and their addition salts and their tautomeric forms, when a tautomeric equilibrium exists.

Mention may be made, among pyrazole derivatives, of the compounds described in Patents DE 3843892 and DE 4 133957 and Patent Applications WO 94/08969, WO 94/08970, FR-A-2733749 and DE 19543988, such as 4,5-diamino- 1 -methylpyrazole, 4,5-diamino- 1 - ( -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 -phenyl- pyrazole, 4 -amino - 1 ,3-dimethyl-5-hydrazinopyrazole, 1 -b enzy 1-4,5 - diamino-3-methylpyrazole, 4,5-diamino-3-(tert-butyl) - 1 -methyl- pyrazole, 4,5-diamino - 1 -(tert-butyl)-3-methylpyrazole, 4,5-diamino - 1 - ( β -hydroxy ethyl)- 3 -methylpyrazole, 4,5-diamino - 1 - ethyl- 3 -methyl- pyrazole, 4,5-diamino-l-ethyl-3-(4'-methoxyphenyl)pyrazole, 4,5- diamino- 1 -ethyl- 3 -(hydroxymethyl)pyrazole, 4,5-diamino -3 -hydroxy- methyl- 1 -methylpyrazole, 4,5-diamino-3-hydroxymethyl- 1 -isopropyl- pyrazole, 4,5-diamino -3 -methyl- 1 -isopropylpyrazole, 4-amino-5-(2'- amino ethyl) amino - 1 ,3-dimethylpyrazole, 3 ,4,5-triaminopyrazole, 1 - methyl-3,4,5-triaminopyrazole, 3,5-diamino- 1 -methyl- 4- (methy 1- amino)pyrazole, 3,5-diamino-4-( -hydroxyethyl)amino- 1 -methylpyrazole and their addition salts. Use may also be made of 4,5- diamino- 1 - ( -methoxyethyl)pyrazole.

Use will preferably be made of a 4,5-diaminopyrazole and more preferably still of 4,5-diamino-l-(P-hydroxyethyl)pyrazole and/or one of its salts.

Mention may also be made, as pyrazole derivatives, of diamino-N,N-dihydropyrazolopyrazolones, in particular those described in Application FR-A-2886 136, such as the following compounds and their addition salts: 2,3-diamino-6,7-dihydro-lH,5H- pyrazolo[ 1 ,2-a]pyrazol- 1 -one, 2-amino-3-ethylamino-6,7-dihydro- lH,5H-pyrazolo[ 1 ,2-a]pyrazol- 1 -one, 2-amino-3-isopropylamino-6,7- dihydro- lH,5H-pyrazolo[ 1 ,2-a]pyrazol- 1 - one, 2-amino-3-(pyrrolidin- l-yl)-6,7-dihydro-lH,5H-pyrazolo[l,2-a]pyrazol-l-one, 4,5-diamino- 1 ,2-dimethyl-l ,2-dihydropyrazol-3-one, 4,5-diamino- 1 ,2-diethyl- 1 ,2- dihydropyrazol-3-one, 4,5-diamino- 1 ,2-di(2-hydroxy ethyl)- 1 ,2- dihydropyrazol-3-one, 2-amino-3-(2-hydroxyethyl)amino-6,7-dihydro- lH,5H-pyrazolo[ 1 ,2-a]pyrazol- 1 -one, 2-amino-3-dimethylamino-6,7- dihydro-lH,5H-pyrazolo[ 1 ,2-a]pyrazol- 1 -one, 2,3-diamino-5,6,7,8- tetrahydro- lH,6H-pyridazino[ 1 ,2-a]pyrazol- 1 -one, 4 -amino - 1 ,2- diethyl-5-(pyrrolidin-l-yl)-l ,2-dihydropyrazol-3-one, 4- amino -5- [3 - (dimethyl amino )pyrrolidin- 1 -yl] - 1 ,2-diethyl- 1 ,2-dihydropyrazol-3-one or 2,3-diamino-6-hydroxy-6,7-dihydro-lH,5H-pyrazolo[ 1 ,2-a]pyrazol- 1-one. It will be preferable to use 2,3-diamino-6,7-dihydro-lH,5H- pyrazolo[ 1 ,2-a]pyrazol- 1 -one and/or one of its salts.

Use will preferably be made, as heterocyclic bases, of 4,5- diamino- 1 -(β- hydro xyethyl)pyrazole and/or 2,3-diamino-6,7-dihydro- lH,5H-pyrazolo[l,2-a]pyrazol-l-one and/or one of their salts.

The couplers which can be used in the present invention can be chosen from those conventionally used for dyeing keratinous fibres.

Mention may in particular be made, among these couplers, of meta-phenylenediamines, meta-aminophenols, meta-diphenols, naphthalene couplers or heterocyclic couplers and their addition salts.

Mention may be made, by way of example, of 1 ,3-dihydroxybenzene, 1 ,3-dihydroxy-2-methylbenzene, 4-chloro - 1 ,3- dihydroxybenzene, 2,4-diamino- 1 -( -hydroxyethyloxy)benzene, 2- amino-4-( -hydroxyethylamino) - 1 -methoxybenzene, 1,3- diaminobenzene, 1 ,3-bis(2,4-diaminophenoxy)propane, 3-ureido- aniline, 3-ureido- 1 -dimethylaminobenzene, sesamol, Ι-β-hydroxy- ethylamino-3,4-methylenedioxybenzene, cc-naphthol, 2-methyl-l- naphthol, 6-hydroxyindole, 4-hydroxyindole, 4-hydroxy-N-methyl- indole, 2-amino-3-hydroxypyridine, 6-hydroxybenzomorpholine, 3,5- diamino-2,6-dimethoxypyridine, 1 -N- (β -hydroxy ethyl) amino -3,4- methylenedioxybenzene, 2,6-bis( -hydroxyethylamino)toluene, 6- hydroxyindoline, 2,6-dihydroxy-4-methylpyridine, lH-3-methyl- pyrazol-5-one, 1 -phenyl-3-methylpyrazol-5-one, 2,6-dimethyl- pyrazolo[ 1 ,5-b] [ 1 ,2,4]triazole, 2,6-dimethyl[3,2-c] [ 1 ,2,4]triazole, 6- methylpyrazolo[ 1 ,5-a]benzimidazole, their addition salts with an acid and their mixtures.

Generally, the addition salts of the oxidation bases and couplers which can be used in the context of the invention are chosen in particular from the addition salts with an acid, such as hydrochlorides, hydrobromides, sulphates, citrates, succinates, tartrates, lactates, tosylates, benzenesulphonates, phosphates and acetates.

The oxidation base or bases can each advantageously represent from 0.0001 to 10% by weight, with respect to the total weight of the dispersion (A), and preferably from 0.005 to 5 % by weight, with respect to the total weight of this dispersion.

The coupler or couplers, if they are present, can each advantageously represent from 0.0001 to 1 0% by weight, with respect to the total weight of the dispersion (A), and preferably from 0.005 to 5 % by weight, with respect to the total weight of this dispersion.

According to a second embodiment of the invention, the dispersion (A) comprises one or more direct dyes .

According to one embodiment, the dispersion (A) can comprise one or more oxidation dyes and, as additional dye, one or more direct dyes .

According to another embodiment, the dispersion (A) does not comprise oxidation dyes; the agent according to the invention is then advantageously used for the lightening direct dyeing o f keratinous fibres.

The direct dyes capable of being employed in the dispersion (A) are more particularly chosen from ionic or nonionic entities, preferably cationic or nonionic entities.

Mention may be made, as examples o f suitable direct dyes, of azo, methine, carbonyl, azine, nitro(hetero)aryl or tri(hetero)arylmethane direct dyes, porphyrins, phthalocyanines and natural direct dyes, alone or as mixtures .

More particularly, azo dyes comprise an -N=N- functional group, the two nitrogen atoms o f which are not simultaneously participants in a ring. However, it is not out of the question for one of the two nitrogen atoms o f the -N=N- sequence to be a participant in a ring.

Dyes of the family of the methines are more particularly compounds comprising at least one sequence chosen from >C=C< and -N=C<, the two atoms of which are not simultaneously participants in a ring. However, it is specified that one of the nitrogen or carbon atoms o f the sequences can be a participant in a ring. More particularly, the dyes of this family result from compounds of the fo llowing types : methine, azomethine, mono- and diarylmethane, indoamines (or diphenylamines), indophenols, indoanilines, carbocyanines, azacarbocyanines and their isomers, diazacarbocyanines and their isomers, tetraazacarbocyanines or hemicyanines .

As regards dyes of the family of the carbonyls, mention may be made, for example, of dyes chosen from acridone, benzoquinone, anthraquinone, naphthoquinone, benzanthrone, anthranthrone, pyranthrone, pyrazo lanthrone, pyrimidinoanthrone, flavanthrone, indanthrone, flavone, (iso)vio lanthrone, isoindo linone, benzimidazolone, isoquino linone, anthrapyridone, pyrazoloquinazolone, perinone, quinacridone, quinophthalone, indigoid, thioindigo, naphthalimide, anthrapyrimidine, diketopyrrolopyrrole or coumarin dyes .

As regards dyes of the family o f the cyclic azines, mention may in particular be made of azine, xanthene, thioxanthene, fluorindine, acridine, (di)oxazine, (di)thiazine or pyronine dyes .

The nitro(hetero)aromatic dyes are more particularly nitrobenzene or nitropyridine direct dyes .

As regards the dyes of porphyrin or phthalocyanine type, use may be made of cationic or noncationic compounds optionally comprising one or more metals or metal ions, such as, for example, alkali and alkaline earth metals, zinc and silicon.

Mention may be made, as examples of direct dyes which are particularly suitable, of nitrobenzene dyes, azo, azomethine or methine direct dyes, azacarbocyanines, such as tetraazacarbocyanines (tetraazapentamethines), quinone and in particular anthraquinone, naphthoquinone or benzoquinone direct dyes, azine, xanthene, triarylmethane, indoamine or indigoid direct dyes, phthalocyanines, porphyrins and natural direct dyes, alone or as mixtures .

These dyes can be monochromophoric dyes (that is to say, comprising only a single chromophore) or polychromophoric dyes, preferably di- or trichromophoric dyes, it being possible for the chromophores to be identical or different and from the same or a different chemical family. It should be noted that a polychromophoric dye comprises several radicals, each resulting from a mo lecule which absorbs in the visible region between 400 and 800 nm. Furthermore, this absorbance of the dye requires neither preoxidation of the latter nor combination with other chemical entity(ies) .

In the case o f po lychromophoric dyes, the chromophores are connected to one another by means o f at least one connecting arm, which may or may not be cationic.

Preferably, the connecting arm is a linear, branched or cyclic C 1 - C20 alkyl chain which is optionally interrupted by at least one heteroatom (such as nitrogen or oxygen) and/or by at least one group comprising it (CO, S0₂), which is optionally interrupted by at least one heterocycle which may or may not be fused with a phenyl nucleus and which comprises at least one quaternized nitrogen atom participating in the said cycle and optionally at least one other heteroatom (such as oxygen, nitrogen or sulphur), which is optionally interrupted by at least one substituted or unsubstituted phenyl or naphthyl group and which is optionally interrupted by at least one quaternary ammonium group substituted by two optionally substituted C 1 - C 1 5 alkyl groups, the connecting arm not comprising a nitro, nitroso or peroxo group .

If the heterocycles or aromatic nuclei are substituted, they are substituted, for example, by one or more C i -Cs alkyl radicals optionally substituted by a hydroxyl group, a C 1 - C2 alkoxy group, a C2 - C4 hydroxyalkoxy group, an acetylamino group, an amino group substituted by one or two C 1 - C4 alkyl radicals which optionally carry at least one hydroxyl group or it being possible for the two radicals to form, with the nitrogen atom to which they are attached, a 5 - or 6- membered heterocycle optionally comprising another heteroatom identical to or different from nitrogen; a halogen atom; a hydroxyl group; a C 1 - C2 alkoxy radical; a C2 - C4 hydroxyalkoxy radical; an amino radical; or an amino radical substituted by one or two identical or different C 1 - C4 alkyl radicals which optionally carry at least one hydroxyl group . Mention may be made, among the benzene direct dyes which can be used according to the invention, without implied limitation, of the fo llowing compounds :

- 1 ,4-diamino-2-nitrobenzene

- 1 -amino-2-nitro-4-(P-hydroxyethylamino)benzene

- 1 - amino -2 -nitro -4- [bis(P- hydro xyethyl)amino] benzene

- 1 ,4-bis(P-hydroxyethylamino)-2-nitrobenzene

- 1 - (β-hydroxy ethylamino) -2 -nitro -4 - [bis(P- hydroxy ethyl) amino] benzene

- 1 -(P-hydroxyethylamino)-2-nitro-4-aminobenzene

- 1 - (β-hydroxy ethylamino) -2 -nitro -4 - [(ethyl)(P-hydroxy- ethyl)amino] benzene

- 1 - amino -3 -met hy 1-4- (β- hydro xyethylamino)- 6 -nitrobenzene

- 1 - amino -2-nitro-4-(P-hydroxyethylamino)-5 -chlorobenzene - 1 ,2-diamino-4-nitrobenzene

- 1 - amino -2- (β- hydroxy ethylamino)- 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 -amino benzene

- 1 -hydroxy-2 -amino -4, 6 -dinitrobenzene

- 1 - (P-hydroxyethyloxy)-2-(P-hydroxyethylamino)-5 - nitrobenzene

- 1 -methoxy-2-(P-hydroxyethylamino)-5 -nitrobenzene

- 1 -(P-hydroxyethyloxy)-3 -methylamino-4-nitrobenzene

- 1 -( β, γ-dihydroxypropyloxy)- 3 -met hylamino -4 -nitrobenzene

- l-(P-hydroxyethylamino)-4-(P,y-dihydroxypropyloxy)-2- nitrobenzene

- 1 -(P,y-dihydroxypropylamino)-4-trifluoromethyl-2- nitrobenzene

- 1 -(P-hydroxyethylamino)-4-trifluoromethyl-2-nitrobenzene

- 1 -( β-hydroxy ethylamino)- 3 -methy 1-2 -nitrobenzene

- 1 -(β- amino ethylamino)- 5 -methoxy-2 -nitrobenzene - 1 -hydroxy-2-chloro-6-ethylamino-4-nitrobenzene

- 1 -hydroxy-2-chloro-6-amino-4-nitrobenzene

- 1 -hy dro xy- 6 - [bis(P- hydroxy ethyl) amino] -3 -nitrobenzene

- 1 -(P-hydroxyethylamino)-2-nitrobenzene

- 1 -hydroxy-4-(P-hydroxyethylamino)- 3 -nitrobenzene.

Mention may be made, among the azo, azomethine, methine or tetraazapentamethine direct dyes which can be used according to the invention, o f the cationic dyes described in Patent Applications WO 95/ 15 144, WO 95/01772 and EP 714 954; FR 2 1 89 006, FR 2 285 85 1 , FR 2 140 205 , EP 1 378 544 and EP 1 674 073.

Thus, mention may very particularly be made o f the fo llowing dyes o f formulae (I) to (IV) below and preferably of the compounds of fo llowing formulae (I) and (III) :

in which:

D represents a nitrogen atom or the -CH group,

Ri and R₂, which are identical or different, represent a hydrogen atom; a C ₁ -C₄ alkyl radical which can be substituted by a -CN, -OH or -NH₂ radical or form, with a carbon atom of the benzene ring, an optionally oxygen-comprising or nitrogen-comprising heterocycle which can be substituted by one or more C ₁ -C₄ alkyl radicals; or a 4'- aminophenyl radical,

R3 and R'3 , which are identical or different, represent a hydrogen atom, a halo gen atom chosen from chlorine, bromine, iodine and fluorine, a cyano radical, a C ₁ -C₄ alkyl radical, a C ₁ -C₄ alkoxy radical or an acetyloxy radical,

X^" represents an anion, preferably chosen from chloride, methyl sulphate and acetate,

A represents a group chosen from the fo llowing structures Ai to Ai 8 , preferably A_{l s} A₄ , A₇ , A and Ai ₈ :

in which R₄ represents a Ci-C₄ alkyl radical which can be substituted by a hydroxyl radical and R₅ represents a Ci-C₄ alkoxy radical;

in which:

R₆ represents a hydrogen atom or a C₁-C4 alkyl radical,

R₇ represents a hydrogen atom, an alkyl radical which can be substituted by a -CN radical or by an amino group, or a 4'- aminophenyl radical, or forms, with R₆, an optionally oxygen- comprising and/or nitrogen-comprising heterocycle which can be substituted by a C₁-C4 alkyl radical,

R8 and R9, which are identical or different, represent a hydrogen atom, a halogen atom, such as bromine, chlorine, iodine or fluorine, a C₁-C4 alkyl radical, a C₁-C4 alkoxy radical or a -CN radical,

X^" represents an anion, preferably chosen from chloride, methyl sulphate and acetate,

B represents a group chosen from the following structures Bl

B4 B5 B6

in which Rio represents a C₁-C4 alkyl radical and Rn and R₁₂, which are identical or different, represent a hydrogen atom or a C₁-C4 alkyl radical;

(III)

in which:

Ri3 represents a hydrogen atom, a C1-C4 alkoxy radical or a halogen atom, such as bromine, chlorine, iodine or fluorine,

Ri4 represents a hydrogen atom or a C1-C4 alkyl radical or forms, with a carbon atom of the benzene ring, a heterocycle which may comprise oxygen and/or may be substituted by one or more C1-C4 alkyl groups,

Ri5 represents a hydrogen atom or a halogen atom, such as bromine, chlorine, iodine or fluorine,

Ri6 and Ri7, which are identical or different, represent a hydrogen atom or a C1-C4 alkyl radical,

Di and D₂, which are identical or different, represent a nitrogen atom or the -CH group,

m = 0 or 1, preferably 1,

it being understood that, when R13 represents an unsubstituted amino group, then Di and D₂ simultaneously represent a -CH group and m = 0,

X^" represents an anion, preferably chosen from chloride, methyl sulphate and acetate,

E represents a group chosen from the following structures El to E8, more particularly El, E2 and E7:

in which R' represents a C1-C4 alkyl radical;

when m = 0 and when Di represents a nitrogen atom, then E can also denote a group with the following structure E9:

'

in which R' represents a C1-C4 alkyl radical;

G N J (IV)

in which:

the symbol G represents a group chosen from the following structur

in which structures Gi to G₃:

Ri8 denotes a C1-C4 alkyl radical or a phenyl radical which can be substituted by a C1-C4 alkyl radical or a halogen atom chosen from chlorine, bromine, iodine and fluorine;

Ri9 denotes a C1-C4 alkyl radical or a phenyl radical;

R20 and R21, which are identical or different, represent a C1-C4 alkyl radical or a phenyl radical or together form, in Gi, a benzene ring substituted by one or more C1-C4 alkyl, C1-C4 alkoxy or N0₂ radicals or together form, in G₂, a benzene ring optionally substituted by one or more C1-C4 alkyl, C1-C4 alkoxy or N0₂ radicals;

R20 can additionally denote a hydrogen atom;

Z denotes an oxygen or sulphur atom or an -NR₁₉ group;

M represents a -CH group, a -CR group (R denoting C1-C4 alkyl) or an -NR₂₂(X^~)_r group;

K represents a -CH group, a -CR group (R denoting C1-C4 alkyl) or an -NR₂₂(X^~)_r group;

P represents a -CH group, a -CR group (R denoting C1-C4 alkyl) or an -NR₂₂(X^~)_r group; r denotes zero or 1;

R₂₂ represents an O^" atom, a C1-C4 alkoxy radical or a C1-C4 alkyl radical;

R23 and R₂4, which are identical or different, represent a hydrogen atom, a halogen atom chosen from chlorine, bromine, iodine and fluorine, a C1-C4 alkyl radical, a C1-C4 alkoxy radical or an -N0₂ radical;

X^" represents an anion, preferably chosen from chloride, iodide, methyl sulphate, ethyl sulphate, acetate and perchlorate;

with the proviso that,

if R₂₂ denotes O^", then r denotes zero;

if K or P or M denote -N-(Ci-C₄ alkyl) X^", then R₂₃ or R₂₄ is preferably other than a hydrogen atom;

if K denotes -NR₂₂(X^~)_r, then M = P = -CH or -CR;

if M denotes -NR₂₂(X^")_r, then K = P = -CH or -CR;

if P denotes -NR₂₂(X^")_r, then K = M and denotes -CH or -CR; if Z denotes a sulphur atom with R₂i denoting C1-C4 alkyl, then R₂o is other than a hydrogen atom; if Z denotes -NR₂₂ with R19 denoting C1-C4 alkyl, then at least one of the Ris, R20 or R₂i radicals of the group with the structure G₂ is other than a C1-C4 alkyl radical; the symbol J represents:

-(a) a group with the following structure Ji:

in which structure Ji:

R25 represents a hydrogen atom, a halogen atom chosen from chlorine, bromine, iodine and fluorine or a C1-C4 alkyl, C1-C4 alkoxy, -OH, -NO2, -NHR28, -NR29R30 or -NHCO(Ci-C₄ alkyl) radical or forms, with R26, a 5- or 6-membered ring which may or may not comprise one or more heteroatoms chosen from nitrogen, oxygen or sulphur;

R26 represents a hydrogen atom, a halogen atom chosen from chlorine, bromine, iodine and fluorine, a C1-C4 alkyl radical or a Ci- C4 alkoxy radical,

or forms, with R27 or R28, a 5- or 6-membered ring which may or may not comprise one or more heteroatoms chosen from nitrogen, oxygen or sulphur;

R27 represents a hydrogen atom, an -OH radical, an -NHR28 radical or an -NR29R30 radical;

R28 represents a hydrogen atom, a C1-C4 alkyl radical, a C1-C4 monohydroxyalkyl radical, a C2-C4 polyhydroxyalkyl radical or a phenyl radical;

R29 and R30, which are identical or different, represent a C1-C4 alkyl radical, a C1-C4 monohydroxyalkyl radical or a C2-C4 polyhydroxyalkyl radical;

-(b) a 5- or 6-membered nitrogenous heterocyclic group which is capable of including other heteroatoms and/or carbonyl groups and which can be substituted by one or more C1-C4 alkyl, amino or phenyl radicals, and in particular a group with the following structure J₂:

in which structure J₂:

R31 and R₃₂, which are identical or different, represent a hydrogen atom, a C₁-C4 alkyl radical or a phenyl radical;

CH,

I J_

Y denotes the -CO- radical or the c^= radical;

n = 0 or 1, with, when n denotes 1, U denoting the -CO- radical.

In the structures of the dyes (I) to (IV) defined above, the Ci- C₄ alkyl or alkoxy group preferably denotes methyl, ethyl, butyl, methoxy or ethoxy.

Preference is given, among the dyes of formulae (I) and (III), to the following compounds:

CH,

/

CH,

CH,

Mention may also be made, among azo direct dyes, of the following dyes described in the Colour Index International, 3rd edition:

-Disperse Red 17

-Basic Red 22

-Basic Red 76

-Basic Yellow 57

-Basic Brown 16

-Basic Brown 17

-Disperse Black 9.

Mention may also be made of 1 -(4'-aminodiphenylazo)-2- met hy 1-4 -[bis(P- hydroxy ethyl) amino] benzene.

Mention may be made, among quinone direct dyes, of the following dyes:

-Disperse Red 15

-Solvent Violet 13

-Disperse Violet 1

-Disperse Violet 4

-Disperse Blue 1

-Disperse Violet 8

-Disperse Blue 3

-Disperse Red 11

-Disperse Blue 7

-Basic Blue 22

-Disperse Violet 15

-Basic Blue 99

and the following compounds:

- 1 -(N-methylmorpholiniopropylamino)-4- hydroxy ant hraquinone

- 1 -aminopropylamino-4-(methylamino)anthraquinone

- 1 -(aminopropylamino)anthraquinone

-5-(P-hydroxyethyl)- 1 ,4-diamino anthraquinone

-2-(aminoethylamino)anthraquinone

- 1 ,4-bis(P,y-dihydroxypropylamino)anthraquinone.

Mention may be made, among azine dyes, of the fo llowing compounds :

-Basic Blue 17

-Basic Red 2.

Mention may be made, among triarylmethane dyes which can be used according to the invention, of the fo llowing compounds :

-Basic Green 1

-Basic Vio let 3

-Basic Vio let 14

-Basic Blue 7

-Basic Blue 26.

Mention may be made, among indoamine dyes which can be used according to the invention, of the fo llowing compounds :

-2-(P-hydroxyethylamino)-5 - [bis(P-4'-hydroxy- ethyl) amino ] anilino- 1 ,4-benzoquinone

-2-(P-hydroxyethylamino)-5 -(2'-methoxy-4'-aminoanilino) - 1 ,4- benzoquinone

-3 -N(2'-chloro-4'-hydroxy)phenyl-acetylamino-6-methoxy- 1 ,4- benzoquinone imine

-3 -N(3 '-chloro-4'-methylamino)phenyl-ureido-6-methyl- 1 ,4- benzoquinone imine

- 3 - [4'-N-(ethyl,carbamylmethyl)amino]phenyl-ureido-6- methyl- 1 ,4-benzoquinone imine.

Mention may be made, among dyes of tetraazapentamethine type which can be used according to the invention, of the following compounds which appear in the table below :

X^" represents an anion, preferably chosen from chloride, iodide, methyl sulphate, ethyl sulphate, acetate and perchlorate .

Mention may more particularly be made, among polychromophoric dyes, of symmetrical or asymmetrical di- or trichromophoric azo and/or azomethine (hydrazone) dyes comprising, on the one hand, at least one optionally fused 5 - or 6-membered aromatic heterocycle comprising at least one quaternized nitrogen atom participating in the said heterocycle and optionally interrupted by at least one other heteroatom (such as nitrogen, sulphur or oxygen) and, on the other hand, at least one optionally substituted phenyl or naphthyl group optionally carrying at least one OR group with R representing a hydrogen atom, an optionally substituted Ci-C₆ alkyl radical or an optionally substituted phenyl ring or at least one N(R')₂ group with R', which are identical or different, representing a hydrogen atom, an optionally substituted Ci-C₆ alkyl radical or an optionally substituted phenyl ring, it being possible for the R' radicals to form, with the nitrogen atom to which they are bonded, a saturated

5- or 6-membered heterocycle, or alternatively either and/or both R' radicals can form, each with the carbon atom of the aromatic ring in the ortho position with respect to the nitrogen atom, a saturated 5- or

6- membered heterocycle.

Mention may preferably be made, as cationic aromatic heterocycle, of 5- or 6-membered rings comprising from 1 to 3 nitrogen atoms, preferably 1 or 2 nitrogen atoms, one being quaternized, the said heterocycle furthermore optionally being fused with a benzene ring. It should likewise be noted that the heterocycle can optionally comprise another heteroatom other than nitrogen, such as sulphur or oxygen.

If the heterocycles or phenyl or naphthyl groups are substituted, they are substituted, for example, by one or more Ci-Cs alkyl radicals optionally substituted by a hydroxyl group, a Ci-C₂ alkoxy group, a C₂-C₄ hydroxyalkoxy group, an acetylamino group, an amino group substituted by one or two Ci-C₄ alkyl radicals which optionally carry at least one hydroxyl group or it being possible for the two radicals to form, with the nitrogen atom to which they are attached, a 5- or 6-membered heterocycle optionally comprising another heteroatom identical to or different from nitrogen; a halogen atom; a hydroxyl group; a Ci-C₂ alkoxy radical; a C₂-C₄ hydroxyalkoxy radical; an amino radical; or an amino radical substituted by one or two identical or different Ci-C₄ alkyl radicals which optionally carry at least one hydroxyl group.

These polychromophores are connected to one another by means of at least one connecting arm optionally comprising at least one quaternized nitrogen atom which may or may not participate in a saturated or unsaturated and optionally aromatic heterocycle.

Preferably, the connecting arm is a linear, branched or cyclic C 1 - C20 alkyl chain which is optionally interrupted by at least one heteroatom (such as nitrogen or oxygen) and/or by at least one group comprising it (CO, S0₂), which is optionally interrupted by at least one heterocycle which may or may not be fused with a phenyl nucleus and which comprises at least one quaternized nitrogen atom participating in the said cycle and optionally at least one other heteroatom (such as oxygen, nitrogen or sulphur), which is optionally interrupted by at least one substituted or unsubstituted phenyl or naphthyl group and which is optionally interrupted by at least one quaternary ammonium group substituted by two optionally substituted C 1 - C 1 5 alkyl groups, the connecting arm not comprising a nitro, nitroso or peroxo group .

The connection between the connecting arm and each chromophore is generally made by means of a heteroatom substituting the phenyl or naphthyl nucleus or by means of the quaternized nitrogen atom o f the cationic heterocycle.

The dye can comprise identical or different chromophores .

Reference may in particular be made, as examples of such dyes, to Patent Applications EP 1 637 566 , EP 1 619 221 , EP 1 634 926 , EP 1 619 220 , EP 1 672 033 , EP 1 671 954, EP 1 671 955 , EP 1 679 3 12 , EP 1 671 95 1 , EP 167 952 , EP 167 971 , WO 06/063866, WO 06/063867, WO 06/063868 , WO 06/063869, EP 1 408 919 , EP 1 377 264 , EP 1 377 262 , EP 1 377 261 , EP 1 377 263 , EP 1 399 425 , EP 1 399 1 17 , EP 1 416 909, EP 1 399 1 16 and EP 1 671 560.

Use may also be made of cationic direct dyes mentioned in Applications EP 1 006 153 , which describes dyes comprising two chromophores of anthraquinone type connected by means of a cationic connecting arm; EP 1 433 472 , EP 1 433 474 , EP 1 433 471 and EP 1 433 473 , which describe identical or different dichromophoric dyes connected via a cationic or noncationic connecting arm. Mention may be made, among natural direct dyes which can be used according to the invention, o f lawsone, juglone, alizarin, purpurin, carminic acid, kermesic acid, purpurogallin, protocatechualdehyde, indigo, isatin, curcumin, spinulosin, apigenidin, orceins, brazilin, brazilein, haematein or haematoxylin. Use may also be made o f extracts or decoctions comprising these natural dyes and in particular cataplasms or henna-based extracts .

When they are present, the direct dye or dyes advantageously represent from 0.0001 to 10% by weight of the total weight of the dispersion (A) and preferably from 0.005 to 5 % by weight.

According to a third embodiment of the invention, the dispersion (A) and the emulsion (B) do not comprise a direct dye or oxidation dye precursor (bases and couplers) or else, if they are present, their total content does not exceed 0.005 % by weight, with respect to the weight of each composition.

In this embodiment, the agent according to the invention is advantageously used for the bleaching of keratinous fibres.

In this embo diment, the dispersion (A) can advantageously comprise one or more so lid or pasty and preferably pulverulent adjuvants . The adjuvants can then be chosen from salts other than ammonium salts, natural or synthetic thickeners other than those defined above, optionally mo dified starch, glass beads, silica, nylon, alumina, titanium dioxide, zeolites, poly(methyl methacrylate) (PMMA), chitosan, maltodextrin, cyclodextrin, mono- or disaccharides, such as glucose, sucrose, sorbito l or fructose, zinc oxide, zirconium oxide, silica beads, talc, borosilicates, in particular calcium borosilicate, polyethylene, polytetrafluoroethylene (PTFE), cellulo se and its derivatives, superabsorbent compounds, magnesium carbonate, calcium carbonate, polyacrylamide, porous hydroxyapatite, sawdust, fucus powder, crosslinked polyvinylpyrrolidone, calcium alginate, active charcoal, po ly(vinylidene chloride/acrylonitrile) particles, in particular those sold under the general name o f "Expancel^®" by Akzo Nobel and under the specific references "Expancel^® WE " or "DE" Expancels, and their mixtures. Generally, the dispersion (A) and the emulsion (B) constitute a cosmetically acceptable medium optionally comprising one or more organic so lvents.

Mention may be made, as organic so lvent, for examp le, o f linear or branched C₂ - C4 alkanols, such as ethano l and isopropano l; glycerol; polyo ls and polyo l ethers, such as 2-butoxyethanol, propylene glycol, dipropylene glycol, propylene glycol monomethyl ether, diethylene glyco l monoethyl ether and diethylene glyco l monomethyl ether, aromatic alcohols, such as benzyl alcohol or phenoxyethano l, and their mixtures .

Such organic solvents can be present in proportions preferably of between 1 and 40% by weight, with respect to the total weight of each composition in which they are present, more preferably between 5 and 30% by weight.

The dispersion (A) and/or the emulsion (B) according to the present invention can also comprise one or more adjuvants chosen from those conventionally used in compositions for dyeing and/or bleaching keratinous fibres, such as conditioning polymers, in particular cationic conditioning po lymers; antioxidants; penetration agents; sequestering agents; fragrances; dispersants; film-forming agents; ceramides; preservatives; or opacifying agents .

The emulsion (B) according to the present invention can also comprise the thickening agents as described above for the dispersion (A) .

The above adjuvants can generally be present in an amount of, for each o f them, between 0.01 and 20%> by weight, with respect to the weight of each composition.

Another subj ect-matter of the present invention is a method for dyeing and/or bleaching keratinous fibres comprising the application, to the said fibres, of the agent as described above.

According to the invention, the agent applied to the keratinous fibres results from the mixing of the dispersion (A) and of the emulsion (B) , this mixing being carried out either before application to the keratinous fibres (preparation at the time of use) or directly on the keratinous fibres (successive application to the fibres o f the dispersion (A) and of the emulsion (B) without intermediate rinsing) .

Thus, according to a first alternative form o f the method according to the invention, the dispersion (A) and then the emulsion (B) are applied, successively and without intermediate rinsing, to the dry or wet keratinous fibres .

According to a second alternative form o f the method according to the invention, a composition obtained by mixing the dispersion (A) and the emulsion (B) at the time of use, before application, is applied to the dry or wet keratinous fibres .

In this case, the time between the mixing of the dispersion (A) and o f the emulsion (B) and the application of the mixture to the hair then preferably does not exceed 30 minutes, preferably 10 minutes, more preferably still 5 minutes.

Independently o f the alternative form employed, the ratio by weight of the amount of the dispersion (A) used to the amount of the emulsion (B) used can vary from 0.2 to 3 and preferably from 0.3 to 1 .

In addition, independently o f the alternative form emp loyed, the mixture present on the fibres (resulting either from the mixing at the time o f use o f the dispersion (A) and of the emulsion (B) or from the successive application of these) is left in place for a time generally o f the order of 1 minute to 1 hour, preferably o f 5 minutes to 30 minutes.

The temperature during the method is conventionally between ambient temperature (between 15 and 25 °C) and 80°C , preferably between ambient temperature and 60° C .

On conclusion of the treatment, the keratinous fibres are optionally rinsed with water, optionally subjected to washing with a shampoo, followed by rinsing with water, before being dried or left to dry.

Finally, another subj ect-matter of the invention is a dyeing and/or bleaching kit or multicompartment device comprising a first compartment including a dispersion (A) and a second compartment including an emulsion (B), the dispersion (A) and the emulsion (B) being as described above. This device can also comprise one or more compositions for washing and/or conditioning keratinous fibres intended to be applied before and/or after the dyeing and/or bleaching treatment according to the invention.

This device can advantageously be equipped with a means which makes it possible to dispense the desired mixture over the hair, such as the devices described in Patent FR 2586913.

Finally, the invention relates to the use of the agent as defined above in the dyeing and/or bleaching of keratinous fibres, in particular human keratinous fibres, such as the hair.

The fo llowing examples serve to illustrate the invention without, however, exerting a limiting nature.

EXAMPLE

The fo llowing oxidation dyeing dispersions were prepared (in the table below, the amounts are expressed as % by weight) :

Dispersions ( % by weight) C l C2

Liquid petrolatum 5 1 .5 5 1 .5

Octyldodecanol 9 9

Distearyldimethylammonium-

- 4

modified hectorite

Propylene carbonate - 1 .4

Aculyn 44 6 -

Propylene glyco l 2 2

Ethano l 3 3

Hexylene glyco l 1 1

Dipropylene glyco l 1 1

Monoethano lamine 4 4

Ascorbic acid 0.25 0.25

1 -Methyl-2,5 -diaminobenzene 0. 17 0. 17

1 -Hydroxy-4-aminobenzene 0.2 0.2

Resorcino l 0. 1 0. 1 l -Methyl-2-hydroxy-4-(P- 0.25 0.25 hydro xyethylamino)benzene

1 -Methyl-2- hydro xy-4-aminobenzene 0.28 0.28

q. s. for q. s. for

Water

100 100

The water-in-oil(s) dispersions C I and C2 correspond to the dispersion (A) in accordance with the present invention.

The oxidizing emulsion C3 corresponds to the emulsion (B) accordance with the present invention.

At the time o f use, one part by weight of C I or C2 is mixed with one part by weight of C3.

The mixture is subsequently applied to locks of hair comprising 90% natural white hairs . After a leave-in time o f 30 minutes at ambient temperature (23 ° C), the hair is rinsed, washed with a standard shampoo and then dried. A mahogany blonde colouring is then obtained.

Claims

1. Agent for dyeing and/or bleaching keratinous fibres, comprising:

- a surfactant-free water-in-oil dispersion (A), comprising:

- at least 30% by weight, with respect to the weight of the dispersion, of one or more oils not comprising a carboxylic acid functional group,

- water,

- one or more basifying agents, and

- optionally one or more thickening agents chosen from inorganic thickeners and associative polymers, and

- a direct oil-in-water emulsion (B), comprising:

- water,

- one or more oils not comprising a carboxylic acid functional group,

- one or more oxidizing agents,

- one or more surfactants, and

the total amount of the said oils present in the mixture of the dispersion (A) and of the emulsion (B) representing at least 20% by weight, with respect to the total weight of the said mixture.

2. Agent according to Claim 1, characterized in that the basifying agent present in the dispersion (A) is chosen from aqueous ammonia, alkaline carbonates, alkanolamines and their derivatives, sodium hydroxide, potassium hydroxide and compounds of following formula (I):

Rx Rz

W N

Ry ^XRt _(I)

in which W is a Ci-C₆ alkylene residue optionally substituted by a hydroxyl group or a Ci-C₆ alkyl radical and Rx, Ry, Rz and Rt, which are identical or different, represent a hydrogen atom or a Ci-C₆ alkyl, Ci-C₆ hydroxyalkyl or amino(Ci-C₆ alkyl) radical; and is preferably chosen from alkano lamines.

3. Agent according to either one of the preceding claims, characterized in that the oxidizing agent present in the emulsion (B) is chosen from hydrogen peroxide, urea hydrogen peroxide, alkali metal bromates or ferricyanides, peroxygenated salts, preferably alkali metal or alkaline earth metal persulphates, perborates and percarbonates, or oxidation/reduction enzymes, preferably laccases, peroxidases and 2- electron oxidoreductases, optionally in the presence of their respective donor or cofactor, and is preferably hydrogen peroxide.

4. Agent according to any one of the preceding claims, characterized in that the thickening agent present in the dispersion (A) is an organophilic clay chosen from montmorillonite, bentonite, hectorite, attapulgite, sepiolite and their mixtures, the clay optionally being modified.

5. Agent according to any one of Claims 1 to 3 , characterized in that the thickening agent present in the dispersion (A) is an associative po lymer chosen from associative polyurethanes which are more particularly cationic or nonionic, associative cellulo se derivatives which are more particularly cationic or nonionic, associative vinyllactams, associative unsaturated polyacids, associative aminoplast ethers, associative po lymers or copolymers comprising at least one monomer comprising ethylenic unsaturations and comprising a sulpho group, alone or as mixtures .

6. Agent according to any one of the preceding claims, characterized in that the concentration o f thickening agent present in the dispersion (A) is between 0.01 and 10% by weight, more particularly between 0. 1 and 5 % by weight, with respect to the weight of the dispersion (A) .

7. Agent according to any one of the preceding claims, characterized in that the surfactant present in the emulsion (B) is chosen from nonionic and anionic surfactants .

8. Agent according to the preceding claim, characterized in that the surfactant present in the emulsion (B) is chosen from oxyalkylenated nonionic surfactants preferably belonging to the fo llowing families :

- oxyethylenated alkylphenols,

- EO/PO condensates,

- oxyethylenated vegetable oils,

- oxyethylenated fatty alcoho ls,

- esters of fatty acids and of polyethylene glyco ls,

- esters of fatty acids and of sorbitol which are polyoxyethylenated.

9. Agent according to any one of the preceding claims, characterized in that the oil or oils not comprising a carboxylic acid functional group are chosen from hydrocarbons, nonsilicone oils of animal, vegetable, mineral or synthetic origin, fatty alcoho ls, fatty acid and/or fatty alcoho l esters, silicones and their mixtures; preferably from liquid petrolatum, polydecenes, liquid esters of fatty acids and/or of fatty alcoho ls, liquid fatty alcoho ls and their mixtures; and more preferably from liquid petrolatum, polydecenes, liquid fatty alcoho ls and their mixtures.

10. Agent according to any one o f the preceding claims, characterized in that the emulsion (B) comprises from 5 to 50% by weight, preferably from 10 to 30%> by weight, with respect to the total weight of the emulsion (B), of one or more oils not comprising a carboxylic acid functional group .

1 1 . Agent according to any one o f the preceding claims, characterized in that the total amount of oil(s) not comprising a carboxylic acid functional group in the mixture o f the dispersion (A) and o f the emulsion (B) represents at least 25 % by weight, preferably at least 30% by weight, with respect to the total weight of the mixture.

12. Agent according to any one o f the preceding claims, characterized in that the dispersion (A) additionally comprises one or more oxidation dyes chosen from oxidation bases, optionally in combination with one or more couplers, and/or one or more direct dyes.

13. Agent according to any one of Claims 1 to 1 0, characterized in that the dispersion (A) and the emulsion (B) comprise a total content of direct dyes or oxidation dye precursors (bases and couplers) not exceeding 0.005 % by weight, with respect to the weight of each composition.

14. Method for dyeing and/or bleaching keratinous fibres comprising the application o f the dispersion (A) and then of the emulsion (B) as defined in any one of the preceding claims, successively and without intermediate rinsing, to the said dry or wet fibres.

15. Method for dyeing and/or bleaching keratinous fibres comprising the application of a composition, obtained by mixing the dispersion (A) and the emulsion (B) as defined in any one of Claims 1 to 13 at the time of use, to the said dry or wet fibres .

16. Dyeing and/or bleaching kit or multicompartment device comprising a first compartment including a dispersion (A) and a second compartment including an emulsion (B), the dispersion (A) and the emulsion (B) being as defined in any one of Claims 1 to 1 3.

17. The use o f the agent as defined in any one of Claims 1 to 13 in the dyeing and/or bleaching of keratinous fibres, in particular human keratinous fibres, such as the hair.