METHOD OF DYEING OR MAKING UP KERATIN FIBRES USING A PIGMENT RESULTING FROM A 1 ,8-DIHYDROXYNAPHTHALENE DERIVATIVE, COMPOSITION

CONTAINING THE PIGMENT AND THE PIGMENT The invention relates to a method of dyeing or making up keratin fibres comprising a pigment resulting from the polymerization, in the presence of a chemical oxidizing agent, of 1 ,8-dihydroxynaphthalene and derivatives thereof; a composition comprising said pigment; a particular pigment and also the method of preparing same. In the field of dyeing keratin fibres such as the hair, it is already known to dye said fibres via various techniques using oxidation dye precursors for "permanent" colourings and direct dyes or pigments for "non-permanent" colourings.

The colour of the keratin fibres, such as the hair, eyelashes and eyebrows of human origin results mainly from melanin pigments secreted by melanocytes. These pigments, of natural origin, in particular comprise black or brown pigments that are known as eumelanins.

Permanent dyeing is carried out using dye compositions containing oxidation dye precursors, which are generally known as oxidation bases, such as ortho- or para- phenylenediamines, ortho- or para-aminophenols and heterocyclic compounds. These oxidation bases are colourless or weakly coloured compounds, which, when combined with oxidizing agents, may give rise to coloured compounds by a process of oxidative condensation. It is possible to vary the shades obtained by combining the oxidation bases with couplers or dye modifiers. This oxidation dyeing process consists in applying, to the keratin fibres, bases or a mixture of bases and couplers with hydrogen peroxide as oxidizing agent, in allowing them to diffuse and then in rinsing the fibres. The colourings which result therefrom are powerful and resistant to external agents, in particular to light, bad weather, washing, perspiration and rubbing actions but have the drawback of degrading the hair in the long run.

"Direct" dyeing does not use the oxidative condensation process and withstands several shampoo washes, in general 5 or 6 shampoo washes. To that end, dye compositions containing direct dyes are used. These dyes, which are coloured and colouring molecules that have an affinity for the fibres, are dissolved in cosmetic solvents and applied to the keratin fibres for a time necessary for obtaining the desired colouring, then rinsed. The colourings that result therefrom are particularly chromatic colourings that are, however, only temporary or semi-permanent since the nature of the interactions that bind the direct dyes to the keratin fibre and their desorption from the surface and/or the core of the fibre are responsible for their weak dyeing power and their poor fastness with respect to washing or perspiration. In order to be seen on dark keratin fibres, the two "direct" or "permanent" dyeing techniques require a prior or simultaneous bleaching of the keratin fibres. This bleaching step, carried out with an oxidizing agent such as hydrogen peroxide or persalts leads to considerable degradation of the keratin fibres, which adversely affects their cosmetic properties. The hair then has a tendency to become coarse, more difficult to disentangle and more brittle.

Another dyeing method consists in using pigments. Indeed, the use of pigment at the surface of the keratin fibres generally makes it possible to obtain temporary colourings that can be seen even on dark keratin fibres since the pigment at the surface masks the natural colour of the fibre.

This technique is generally used when it is desired to give the keratin fibres a colouring that can, if necessary, be rapidly removed.

The use of pigment for dyeing keratin fibres such as the hair is for example described in international application WO 93/02655, the subject of which is a method for the temporary dyeing of keratin fibres using pigments resulting from the oxidizing polymerization of 5,6- dihydroxyindole derivatives. Patent application FR 2 741 530 relates to a method for temporary dyeing that results in a colouring that can be removed at the first shampoo wash, which uses an aqueous dispersion of particles of a particular film-forming polymer and at least one pigment. The colourings obtained by these dyeing methods do not make it possible to offer a wide range of shades.

It is also known to make up keratin fibres such as the eyelashes and eyebrows using mascara that comprises pigments. Mention may be made of mineral pigments based on metallic compounds such as, for example, black and brown iron oxides.

The organic pigments, especially of natural origin, which can be used in the dyeing or making up of keratin fibres are few in number, offering a very limited range of shades or not always having a satisfactory covering power.

Moreover, the colourings or makeup obtained on keratin fibres with these pigments are not satisfactory, especially in terms of dyeing power, of resistance of the colour with respect, in particular, to water, sweat, tears, shampoo washes, and to bad weather and/or of the photostability of the pigments or of the colouring or makeup of said fibres.

Thus, the objectives of the invention are to provide a method of dyeing or making up keratin fibres using pigments, in particular of natural origin, having good fastness, good photostability, and a colour that is deep and/or that is resistant with respect to shampoo washes. These objectives are achieved by the present invention, one subject of which is a method of dyeing or making up keratin fibres, by treating said fibres with one or more pigments capable of being obtained by chemical reaction between:

i) one or more 1 ,8-dihydroxynaphthalene derivatives of formula (I):

salts thereof with mineral or organic acids or bases, optical or geometric isomers thereof, tautomers thereof, and/or solvates thereof such as hydrates;

in which formula (I):

• Ri and R ₆ represent, independently of one another:

- a hydrogen atom,

- a C1-C4 alkyl radical which may be functionalized with one or more hydroxyl or (CrC ₄ )alkoxycarbonyl radicals,

- a carboxylic radical -C0 ₂ H,

- a (Ci-C ₄ )alkoxycarbonyl radical,

- a (Ci-C ₄ )alkylcarbonyl radical which may be functionalized with a (C C ₄ )alkylcarbonyl radical or a (C C ₄ )alkoxycarbonyl radical,

- a Ci-C ₄ alkoxy radical,

- a carboxaldehyde radical -CHO,

• R ₂ and R ₅ represent, independently of one another:

- a hydrogen atom,

- a hydroxyl radical,

- a Ci-C ₄ alkyl radical which may be functionalized with one or more hydroxyl or (Ci-C ₄ )alkoxycarbonyl radicals,

- a carboxylic radical -C0 ₂ H,

- a (Ci-C ₄ )alkoxycarbonyl radical,

- a (Ci-C ₄ )alkylcarbonyl radical which may be functionalized with a hydroxyl radical,

- a Ci-C ₄ alkoxy radical,

- a carboxaldehyde radical -CHO,

• R ₃ and R ₄ represent, independently of one another:

- a hydrogen atom,

- a hydroxyl radical,

- a Ci-C ₄ alkyl radical which may be functionalized with one or more hydroxyl or (CrC ₄ )alkoxycarbonyl radicals,

- a carboxylic radical -C0 ₂ H,

- a (CrC ₄ )alkoxycarbonyl radical,

- a (CrC ₄ )alkylcarbonyl radical which may be functionalized with a (C C ₄ )alkylcarbonyl radical or a (CrC ₄ )alkoxycarbonyl radical,

• R and R ₂ may form, together with the carbon atoms to which they are attached, a heterocycle optionally substituted with an oxo group, such as pyrone, particularly 4- pyrone, which may be functionalized with one or two C C ₄ alkyl radical(s):

o

■ ^X ° ^R with R and R', which may be identical or different, representing a hydrogen atom or a C C ₄ alkyl radical; preferably, R and R' represent a hydrogen atom or R' represents a hydrogen atom and R represents a C C ₄ alkyl radical;

and

ii) one or more chemical oxidizing agents such as alkali or alkaline-earth metal hypochlorites. Another subject of the invention relates to a composition comprising:

one or more pigments capable of being obtained by chemical reaction between i) one or more 1 ,8-dihydroxynaphthalene derivatives of formula (I) as defined previously and ii) one or more chemical oxidizing agents;

and optionally:

o one or more coloured mineral fillers and/or

o a) one or more hydrophobic film-forming polymers and b) one or more volatile solvents.

Another subject of the invention relates to the pigment capable of being obtained by chemical reaction between one or more 1 ,8-dihydroxynaphthalene derivatives of formula (I) as defined previously and one or more alkali or alkaline-earth metal hypochlorites such as sodium hypochlorite.

Another subject of the invention relates to the method of preparing the pigment capable of being obtained by chemical reaction between one or more 1 ,8-dihydroxynaphthalene derivatives of formula (I) as defined previously and one or more alkali or alkaline-earth metal hypochlorites.

Another subject of the invention relates to the use of the pigment capable of being obtained by chemical reaction between one or more 1 ,8-dihydroxynaphthalene derivatives of formula (I) as defined previously and one or more alkali or alkaline-earth metal hypochlorites such as sodium hypochlorite for dyeing keratin fibres, especially human keratin fibres such as the hair, eyelashes and eyebrows.

The dyeing or makeup method according to the invention makes it possible to dye the keratin fibres, using a wide range of colours, with a high covering power.

The use of the pigments according to the invention for treating keratin fibres has the advantage of obtaining on said keratin fibres a visible colouring with a wide range of shades while preserving the physical qualities of said fibres. Furthermore, the pigments according to the invention have the advantage of dyeing human keratin fibres with resulting colourings that are powerful, chromatic and/or resistant to washing, sebum, light, especially sunlight and UV rays, blow drying and/or perspiration, without adversely affecting said fibres. The colourings obtained using the process may also give colours which are homogeneous from the root to the end of a fibre (a low colouring selectivity). The method of dyeing keratin fibres of the invention also makes it possible to obtain a smooth and homogeneous deposit of said pigments. Furthermore, the keratin fibres treated with the dyeing or makeup method of the invention remain highly individualized after treatment with said method and drying. The hairs are not stuck together, do not form clusters of hair and/or there is no deplorable clumping effect on the eyelashes and eyebrows.

For the purposes of the present invention, and unless otherwise indicated:

- The "alkyl" radicals are saturated, linear or branched, generally C C ₄ hydrocarbon- based radicals such as methyl, ethyl, propyl and butyl.

- The "alkoxy" radicals are alkyl-oxy radicals with alkyl as defined previously, preferably Ci-C ₄ alkyl, such as methoxy, ethoxy, propoxy and butoxy.

- The "heterocycle optionally substituted with an oxo group" is a heterocycle fused to the 1 ,8-dihydroxynaphthalene ring system via the F^ and R ₂ radicals; said heterocycle comprising from 5 to 7 ring members, from one to three heteroatoms chosen from oxygen, sulphur or nitrogen atoms, and which may also comprise an oxo or carbonyl group, and an unsaturated group preferably conjugated with the oxo group.

- The expression "chemical oxidizing agent" means an oxidizing agent other than atmospheric oxygen (0 ₂ ).

- The expression "coloured mineral fillers" means non-white particles constituted of metal salts that are insoluble in the cosmetic medium, which can be used in cosmetics, such as those referred to in the Color Index under the chapter "Inorganic Colouring Matters" and bearing the numbers 77000 to 77947, with the exception of white pigments. These coloured mineral fillers may be constituted of a single pigment or of a mixture of pigments and may thus be in the form of nacreous or interference pigments.

- For the purposes of the invention, the term "polymer" means a compound corresponding to the repetition of one or more units (these units resulting from compounds known as monomers). This or these unit(s) is (are) repeated at least twice and preferably at least 3 times.

- The expression "hydrophobic polymer" is understood to mean a polymer having a solubility in water at 25°C of less than 1 % by weight.

- The expression "film-forming polymer" means a polymer that is capable, by itself or in the presence of an auxiliary film-forming agent, of forming a macroscopically continuous film on a support, especially on keratin fibres, and preferably a cohesive film.

- The expression "organic solvent" means an organic substance that is liquid at room temperature (20°C) and atmospheric pressure and is capable of dissolving or dispersing another substance without chemically modifying it.

- The expression "volatile solvent" means a compound that is liquid at room temperature and atmospheric pressure, having a vapour pressure at 20°C of greater than 0.1 mmHg and preferably between 0.1 and 300 mmHg, more preferably still between 0.5 and 200 mmHg.

- The expression "essentially non-solvent medium" means a medium that dissolves less than 1 percent by weight of the coloured mineral particles.

Pigment(s) capable of being obtained by chemical reaction between 1 ,8-dihydroxynaphthal- ene derivative(s) and chemical oxidizing agent(s):

The pigments used in the invention result from the polymerization of 1 ,8- dihydroxynaphthalene derivatives of formula (I) as defined previously, in the presence of at least one chemical oxidizing agent.

One particular embodiment of the invention relates to the pigments capable of being obtained by chemical reaction between one or more chemical oxidizing agents and 1 ,8- dihydroxynaphthalene derivatives of formula (I) for which R-i and R ₆ represent, independently of one another:

- a hydrogen atom,

- a C1-C4 alkyl radical;

- a carboxylic radical -C0 ₂ H,

- a (CrC ₄ )alkoxycarbonyl radical, - a (CrC ₄ )alkylcarbonyl radical which may be functionalized with a (d- C ₄ )alkylcarbonyl radical or a (CrC ₄ )alkoxycarbonyl radical,

more particularly R-i and R ₆ represent, independently of one another:

- a hydrogen atom,

- a Ci-C ₄ alkyl radical;

- a (Ci-C ₄ )alkoxycarbonyl radical,

- a (Ci-C ₄ )alkylcarbonyl radical which may be functionalized with a (C C ₄ )alkylcarbonyl radical or a (C C ₄ )alkoxycarbonyl radical,

According to another particular embodiment of the invention, the pigments result from 1 ,8-dihydroxynaphthalene derivatives of formula (I) which are such that R ₂ and R ₅ represent, independently of one another:

- a hydrogen atom,

- a hydroxyl radical,

- a Ci-C ₄ alkyl radical which may be functionalized with a (C C ₄ )alkoxycarbonyl radical,

- a (Ci-C ₄ )alkoxycarbonyl radical,

- a Ci-C ₄ alkoxy radical.

Another particular embodiment of the invention relates to the pigments capable of being obtained by chemical reaction between one or more chemical oxidizing agents and 1 ,8- dihydroxynaphthalene derivatives of formula (I) for which R ₃ and R ₄ represent a hydrogen atom.

More particularly, the pigments capable of being obtained by chemical reaction between one or more chemical oxidizing agents and 1 ,8-dihydroxynaphthalene derivatives chosen from the following:

OH OH 1 ,8-Dihydroxynaphthalene

(1) extract of fungi of ascomycetes type

1-(1 ,8-Dihydroxy-3-methylnaphthalen-2-yl)ethanone

(2) extract of: Maesopsis eminii, Dianella laevis,

Dianella nigra, Rumex spp. OH OH O 1-(1 ,6,8-Trihydroxy-3-methylnaphthalen-2-

(21) yl)ethanone 6-methyl ether

extract of: Cassia tora, Rhamnus nakaharai

OH OH 1 ,3,8-Trihydroxynaphthalene

(22) extract of: Lachnellula sp., Verticillium dahliae,

Alternaria sp. Stamm 6588

compounds (1) to (22) and also the optical or geometric isomers thereof, tautomers thereof, hydrates thereof and addition salts thereof with an organic or mineral base.

The preferred compounds of formula (I) are the compounds (1), (2), (3), (4), (5), (6), (7), (8), (9), (1 1) and (21). The compounds that are even more preferred are the compounds (1), (2) and (11).

The 1 ,8-dihydroxynaphthalene derivatives of formula (I) used in the invention may be natural, synthetic and/or commercially available. The compounds of formula (I) can be synthesized by means of the synthesis pathways described in the literature. In this respect, mention may in particular be made of the references below:

- Journal of Physical Chemistry A 2007, 1 11 (2), 345-351 ,

- Journal of Organic Chemistry 1990, 55(5), 161 1-1623,

- Journal of the Chemical Society, Chemical Communication 1979, 206, 206,

- Journal of the Chemical Society, Chemical Communication 1979, 206, 1 165,

- Australian Journal of Chemistry 1988, 41 (7), 1087,

- Journal of American Chemical Society 1988, 1 10(18), 6172,

- Synthetic Communication 2007, 37(18), 3041. The pigments according to the invention are capable of being obtained by chemical reaction between one or more chemical oxidizing agents and the salts of acids or bases of 1 ,8-dihydroxynaphthalene derivatives of formula (I). Said acids may be mineral or organic. Preferably, the acid is hydrochloric acid, which results in chlorides. Said bases or alkalinizing agents may be mineral or organic. Mention may be made of the bases or alkalinizing agents mentioned in the section "The pH of the composition" below. In particular, said bases are alkali metal hydroxides, such as sodium hydroxide, which results in sodium salts.

According to one particular embodiment of the invention, the pigment is capable of being obtained by chemical reaction between one or more chemical oxidizing agents and one or more synthetic 1 ,8-dihydroxynaphthalene derivatives of formula (I) that do not exist in nature. According to another preferred embodiment of the invention, the pigment is capable of being obtained by chemical reaction between one or more chemical oxidizing agents and one or more natural 1 ,8-dihydroxynaphthalene derivatives of formula (I).

According to one embodiment, the pigment is capable of being obtained by chemical reaction between one or more chemical oxidizing agents and one or more natural 1 ,8- dihydroxynaphthalene derivatives of formula (I) resulting from extracts of animals, of bacteria, of fungi, of algae or of plants used in their entirety or partially. Preferably, the natural 1 ,8-dihydroxynaphthalene derivative(s) of formula (I) of the invention result from Daldinia concentrica, Diospyros Mollis, Maesopsis eminii, Dianella laevis, Dianella nigra, Rumex spp., Aphis spiraecola, Chaetomium atrobrunneum, Rhamnus frangula, Rhamnus nakaharai, Cassia tora, Cassia quinquangulata, Fusarium culmorum, Senna obliqua, Comantheria briareus, Lachnellula sp., Verticil! i urn dahliae, Alternaria sp. Stamm 6588. These natural 1 ,8-dihydroxynaphthalene derivatives of formula (I) are obtained from extracts, the purification of which can be carried out by simple extraction without chemical treatment or chemical reaction.

The pigment may also be obtained by chemical reaction between one or more chemical oxidizing agents and one or more 1 ,8-dihydroxynaphthalene derivatives of formula (I) resulting from a mixture of extracts comprising natural 1 ,8-dihydroxynaphthalene derivatives of formula (I).

According to one preferred embodiment, the pigment is capable of being obtained from

1 ,8-dihydroxynaphthalene derivatives of formula (I) originating solely from natural extracts.

The natural extracts according to the invention may be in the form of powders or liquids. Preferably, the extracts of the invention are in the form of powders.

The chemical oxidizing agent(s)

As the chemical oxidizing agent that can be used in the dyeing or makeup method of the invention, mention may be made of hypochlorites; peroxides such as hydrogen peroxide and urea peroxide, particularly hydrogen peroxide; alkali metal bromates; persalts such as perborates; peracids particularly magnesium monoperphthalate; molybdates such as sodium molybdate; periodic acid and the water-soluble salts and derivatives thereof; bichromates such as sodium or potassium bichromates; cupric halides such as cupric chloride and cupric bromide and alkali or alkaline-earth metal ferricyanides such as potassium ferricyanide; or several systems that generate hydrogen peroxide such as:

- polymeric complexes that can release hydrogen peroxide, such as polyvinylpyrrolidone/H ₂ 0 ₂ in particular in the form of powders, and the other polymeric complexes described in US 5 008 093; US 3 376 110; US 5 183 901 ;

- metal peroxides that generate hydrogen peroxide in water, for instance calcium peroxide or magnesium peroxide;

- oxidases that produce hydrogen peroxide in the presence of a suitable substrate (for example, glucose in the case of glucose oxidase or uric acid with uricase); and also enzymes, among which mention may be made of peroxidases, 2-electron oxidoreductases, such as uricases, and 4-electron oxygenases such as laccases. According to one preferred embodiment of the invention, the pigment is obtained by reaction of 1 ,8-dihydroxynaphthalene derivatives of formula (I) as defined previously with at least one chemical oxidizing agent chosen from hypochlorites such as alkali or alkaline-earth metal hypochlorites. More particularly, the chemical oxidizing agent is sodium hypochlorite, more commonly known as bleach.

Additional coloured mineral particles

The dyeing or makeup method according to the invention may be carried out using one or more pigments as defined previously and one or more coloured mineral fillers.

The coloured mineral fillers are non-white particles, preferably chosen from iron oxides, complex sulphosilicates such as ultramarine blue, chromium oxides, pyrophosphates, in particular ammonium and alkali or alkaline-earth metal pyrophosphates such as manganese violet and ferrocyanides, in particular alkali or alkaline-earth metal ferrocyanides such as Prussian blue, which is an iron ferrocyanide.

When the coloured mineral filler is a nacreous or interference pigment, the particle size of the powder comprising the pigment resulting from dihydroxynaphthalene of formula (I) as defined varies between 10 and 150 microns.

On the other hand, when the coloured mineral filler is a metal salt, such as an iron or chromium oxide or an iron or manganese salt, the particle size of the particles comprising the pigment resulting from dihydroxynaphthalene of formula (I) as defined previously that constitutes the powder is generally between 0.01 and 5 microns.

Additional polymers and volatile solvents

The dyeing or makeup method of the invention may be carried out using a composition comprising one or more pigments as defined previously, a) one or more hydrophobic film-forming polymers, and b) one or more volatile solvents. Mention may be made of the film-forming polymers and volatile solvents described in patent application FR 2 924 939.

Preferably a) the hydrophobic film-forming polymer(s) is (are) chosen from polymers and copolymers based on polyurethane or on polyacrylate, vinyl ester copolymers, silicone resins, polyurea/polyurethane silicones, copolymers based on silicone resin and on dimethiconol, reactive silicones, polycondensates, copolymers of ionic or nonionic acrylic or vinyl monomers, silicone-based polymers and polymers of natural origin.

The composition may thus comprise one or more volatile solvents b). The volatile solvent(s) may be chosen from water, ethanol, isopropanol, acetone, isododecane, polydimethylsiloxanes with a viscosity of less than 5 est, decamethylcyclopentasiloxane, dodecaethylcyclohexasiloxane or mixtures thereof.

Process for preparing the pigment According to one particular embodiment, the pigment according to the invention is prepared according to the following steps:

A) mixing, in a solvent that dissolves the dihydroxynaphthalene derivative(s) of formula (I) as chosen from water, lower alcohols and aqueous/alcoholic (water/lower alcohol) mixtures, at a temperature between room temperature and the reflux of said solvent, especially not exceeding 100°C inclusive, in particular at room temperature:

1) one or more dihydroxynaphthalene derivatives of formula (I) as defined previously;

2) one or more chemical oxidizing agents as defined previously;

B) leaving the mixture, preferably under stirring, until the pigment that precipitates is obtained, in particular for a time of between 1 second and 48 hours and preferably between 5 minutes and 24 hours;

C) separating the precipitate (pigment) from the supernatant.

According to one particular embodiment of the invention, the dihydroxynaphthalene derivative(s) of formula (I) as defined previously are found, as molar equivalents relative to the oxidizing agent(s), in values of between 1 and 5, i.e. in values of between 1 equivalent of dihydroxynaphthalene derivative(s) of formula (I) per 5 equivalents of chemical oxidizing agent(s) and 5 equivalents of dihydroxynaphthalene derivative(s) of formula (I) per 1 equivalent of chemical oxidizing agent(s). Preferably 2 molar equivalents of dihydroxynaphthalene derivatives of formula (I) as defined previously per 1 molar equivalent of chemical oxidizing agent such as hypochlorites, and more preferably between 1 molar equivalent of dihydroxynaphthalene derivatives of formula (I) as defined previously per 1 molar equivalent of chemical oxidizing agent such as hypochlorites.

Preferably, the condensation reaction in an oxidizing medium is carried out at room temperature, for instance between 20°C and 25°C.

According to one particular embodiment of the invention, the mixture is left stirring until a precipitate is obtained, preferably for a time of between 1 minute and 5 hours, for instance 1 hour. The oxidation may be carried out in an aqueous or water/organic solvent medium, in air using one or more chemical oxidizing agents as defined previously, particularly chosen from hypochlorites, peroxides, especially hydrogen peroxide, peracids, especially magnesium monoperphthalate, molybdates, such as sodium molybdate, periodic acid and the water-soluble salts and derivatives thereof, bichromates, such as sodium or potassium bichromates, cupric chloride, cupric bromide, potassium ferricyanide, ammonium persulphate, ferric nitrate, ferric chloride, ferric perchlorate, salts of rare-earth elements, including in particular cerium; preferably alkali or alkaline-earth metal hypochlorites such as sodium hypochlorite.

It is possible to activate the oxidizing agents with a pH modifier. When an oxidizing agent is used, the pH is preferably alkaline.

An alkalinizing agent may optionally be added: preferably chosen from sodium hydroxide, carbonate salts, guanidine, imidazole, calcium hydroxide and arginine.

A dyeing catalyst may optionally be added. By way of example, this catalyst may be manganese gluconate or zinc gluconate.

The method that is particularly preferred consists in using, as chemical oxidant, one or more hypochlorites particularly chosen from alkali or alkaline-earth metal hypochlorites such as sodium hypochlorite.

The solvent used for forming the pigment according to the invention is preferably constituted of water and may optionally be constituted of a mixture of water and of organic solvent(s). The solvent is chosen so that it rapidly dissolves the dihydroxynaphthalene derivative(s) of formula (I) as defined previously.

Among these organic solvents mention may be made, by way of example, of C C ₆ lower alcohols such as ethyl alcohol, propyl or isopropyl alcohol, te/f-butyl alcohol, alkylene glycols such as ethylene glycol, propylene glycol, alkylene glycol alkyl ethers such as ethylene glycol monomethyl, monoethyl and monobutyl ethers, propylene glycol and dipropylene glycol monomethyl ethers, and methyl lactate. When the solvent is constituted of a water/organic solvent(s) mixture, the organic solvent(s) is (are) present in concentrations of between 0.5% and 90% by weight relative to the total weight of the composition, in particular between 2% and 50% by weight and preferably between 2% and 20% by weight.

According to one particular embodiment of the pigment preparation method, step A of the method is carried out in the presence of coloured mineral fillers. According to this embodiment, the solvent from step A is chosen so that it does not dissolve said fillers.

The method that is particularly preferred consists in using a water/ethanol mixture as solvent.

The oxidants are used in sufficient amounts to form, via oxidation, the pigment resulting from dihydroxynaphthalene derivatives of formula (I) as defined previously.

In the pigment preparation method that optionally comprises coloured mineral fillers as defined previously in the form of particles in accordance with the invention, use is preferably made of:

one or more dihydroxynaphthalene derivatives of formula (I) as defined previously in weight proportions between 0.01 % and 10% and preferably between 0.02% and 7% by weight relative to the total weight of the mixture from step A);

- one or more chemical oxidizing agents as defined previously in weight proportions between 0.02% and 20% and preferably between 0.04% and 14% by weight relative to the total weight of the mixture from step A);

the optional coloured mineral filler(s) representing 0.05% to 70% by weight relative to the total weight of the mixture from step A);

the remainder being constituted of the solvent to reach 100% by weight relative to the total weight of the mixture from step A), the solvent generally being constituted of water or a water/organic solvent(s) mixture.

The proportions are determined relative to the weight of the mixture from step A), i.e. of the reaction medium.

The precipitate that corresponds to the pigment is separated from the supernatant by a conventional purification method, especially by filtration or by centrifugation. The pigment may then be washed one or more times with a solvent, preferably water, then optionally washed again using a lower alcohol such as ethanol or an aqueous/alcoholic mixture, preferably containing ethanol, then optionally dried and/or lyophilized. A powder is then obtained. Form of the pigment according to the invention

The pigment resulting from the dihydroxynaphthalene of formula (I) as defined previously may be in the form of coloured particles or powder that may be added to a conventional cosmetic support, in particular at a concentration between 0.05% and 35% by weight and preferably between 0.1 % and 20% by weight relative to the total weight of the composition in order to result in treatment products for the eyelashes, eyebrows or hair, such as mascaras for the eyelashes and eyebrows or else compositions for the temporary dyeing of the hair. These cosmetic supports are themselves known to those skilled in the art.

The pigment resulting from the dihydroxynaphthalene of formula (I) according to the invention or the mixture of pigment with the coloured mineral filler(s) is in the form of a powder. The particle size of the particles constituting said powder in accordance with the invention is dependent on the particle size of the initial coloured mineral fillers and may vary to a large extent, ranging from 0.01 to 150 microns.

Composition:

The composition according to the invention comprises a cosmetic medium suitable for dyeing or making up keratin fibres, i.e. it generally comprises water or a mixture of water and one or more organic solvents or a mixture of organic solvents.

Organic solvents:

Examples of organic solvents that may be mentioned include C C ₆ lower alkanols, such as ethanol and isopropanol; polyols and polyol ethers such as 2-butoxyethanol, propylene glycol, propylene glycol monomethyl ether, diethylene glycol monoethyl ether and monomethyl ether, hexylene glycol, and also aromatic alcohols, for instance benzyl alcohol or phenoxyethanol.

The organic solvents are present in proportions preferably of between 1 % and 40% by weight approximately and more preferably still between 5% and 30% by weight approximately relative to the total weight of the dye composition.

Adjuvants:

The composition of the invention comprising the pigment(s) that may be obtained from dihydroxynaphthalene derivatives of formula (I) as defined previously may also contain various adjuvants conventionally used in hair dye compositions or mascaras, such as anionic, cationic, nonionic, amphoteric or zwitterionic surfactants or mixtures thereof, anionic, cationic, nonionic, amphoteric or zwitterionic polymers or mixtures thereof, mineral or organic thickeners, and in particular anionic, cationic, nonionic and amphoteric polymeric associative thickeners, antioxidants, penetrants, sequestrants, fragrances, buffers, dispersants, conditioning agents, for instance volatile or non-volatile, modified or unmodified silicones, film-forming agents, ceramides, preserving agents and opacifiers.

The above adjuvants are generally present in an amount for each of them of between

0.01 % and 40% by weight relative to the weight of the composition, and preferably between 0.1 % and 20% by weight relative to the weight of the composition.

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

Additional dyes:

The composition of the invention comprising the pigment(s) that may be obtained from 1 ,8-dihydroxynaphthalene derivatives of formula (I) as defined previously may also comprise one or more additional direct dyes. These direct dyes are chosen, for example, from those conventionally used in direct dyeing, and among which mention may be made of any commonly used aromatic and/or non-aromatic dye such as neutral, acidic or cationic nitrobenzene direct dyes, neutral, acidic or cationic azo direct dyes, natural direct dyes, neutral, acidic or cationic quinone and in particular anthraquinone direct dyes, azine, triarylmethane, indoamine, methine, styryl, porphyrin, metalloporphyrin, phthalocyanine, cyanine and methine direct dyes, and fluorescent dyes.

Among the natural direct dyes, mention may be made of lawsone, juglone, indigo, isatin, curcumin, spinulosin, apigenidin and orceins. Extracts or decoctions containing these natural dyes and especially henna-based poultices or extracts, may also be used.

The additional direct dye(s) used in the composition preferably represent from 0.001 % to 10% by weight approximately of the total weight of the composition(s) containing them, and even more preferentially from 0.05% to 5% by weight approximately. According to one particular embodiment of the invention the composition is a makeup composition for the eyelashes and eyebrows such as mascara that preferably comprises an essentially "non-solvent" medium for the coloured mineral fillers.

The cosmetic composition of the invention may be in various galenic forms, such as a powder, a lotion, a thickened lotion, a foam, a cream or a gel, or in any other form that is suitable for dyeing or making up keratin fibres, milk, powder or stick. They may also be packaged in a propellant-free pump-action bottle or under pressure in an aerosol container in the presence of a propellant and form a foam.

The pH of the composition

The pH of the composition containing the pigment(s) capable of being obtained from one or more 1 ,8-dihydroxynaphthalene derivatives of formula (I) as defined previously and that is preferably used in hair dyeing is between 5 and 12 and preferably between 6 and 9.

The pH of the composition used in making up the eyelashes and eyebrows is preferably at a neutral pH.

The pH of the compositions according to the invention may be adjusted to the desired value by means of acidifying or alkalinizing agents usually used in the dyeing of keratin fibres, or alternatively with the aid of standard buffer systems.

Among the acidifying agents for the compositions used in the invention, examples that may be mentioned include mineral or organic acids, for instance hydrochloric acid, orthophosphoric acid or sulphuric acid, carboxylic acids, for instance acetic acid, tartaric acid, citric acid and lactic acid, and sulphonic acids.

Among the alkalinizing agents, mention may be made of aqueous ammonia, alkanolamines such as monoethanolamine, diethanolamine and triethanolamine, alkali metal carbonate salts, guanidine, imidazole, sodium hydroxide, potassium hydroxide or calcium hydroxide, arginine, and the compounds of formula (II) below:

c ^d (ll)

in which formula (II):

- W is a propylene residue optionally substituted with a hydroxyl group or a C C ₄ alkyl radical;

- R _a , R _b , R _c and R _d , which may be identical or different, represent a hydrogen atom or a Ci-C ₄ alkyl or C C ₄ hydroxyalkyl radical.

More particularly, the alkalinizing agent(s) is (are) chosen from ethanolamine, carbonate salts, guanidine, imidazole, calcium hydroxide and arginine.

One-step or multi-step dyeing or makeup method

One subject of the invention relates to the dyeing or makeup method by treating keratin fibres with one or more pigments capable of being obtained by chemical reaction between i) one or more 1 ,8-dihydroxynaphthalene derivatives of formula (I) as defined previously and ii) one or more chemical oxidizing agents as defined previously. According to one preferred embodiment of the method of the invention, the application is carried out using: a cosmetic composition as defined previously comprising:

- one or more pigments capable of being obtained by chemical reaction between i) one or more 1 ,8-dihydroxynaphthalene derivatives of formula (I) and the chemical oxidizing agent(s) as defined previously;

- one or more hydrophobic film-forming polymers as defined previously, in particular the hydrophobic film-forming polymer(s) is (are) chosen from polymers and copolymers based on polyurethane or on polyacrylate, vinyl ester copolymers, silicone resins, polyurea/polyurethane silicones, copolymers based on silicone resin and on dimethiconol, reactive silicones, polycondensates, copolymers of ionic or nonionic acrylic or vinyl monomers, silicone-based polymers and polymers of natural origin, and

- one or more volatile solvents as defined previously, in particular the volatile solvent(s) is (are) chosen from water, ethanol, isopropanol, acetone, isododecane, polydimethylsiloxanes with a viscosity of less than 5 est, decamethylcyclopentasiloxane, dodecaethylcyclohexasiloxane or mixtures thereof.

The use of the composition containing the pigment(s) resulting from one or more 1 ,8- dihydroxynaphthalene derivatives of formula (I) as defined previously according to the invention may be carried out on dry or wet keratin fibres, and also on any type of light or dark, natural or dyed, permanent-waved or straightened keratin fibres.

According to one particular embodiment, the keratin fibres are washed before application of the composition comprising the pigment(s) resulting from one or more 1 ,8- dihydroxynaphthalene derivatives of formula (I) as defined previously according to the invention.

The application to the keratin fibres may be performed, for example, using a comb, a fine brush, a brush or with the fingers.

The leave-in time after application of the composition according to the invention comprising the pigment(s) resulting from one or more 1 ,8-dihydroxynaphthalene derivatives of formula (I) as defined previously, is set at between 3 and 120 minutes, preferably between 5 and 30 minutes.

Irrespective of the application method, the application temperature is generally between room temperature and 80°C and particularly between 15°C and 45°C, preferably at room temperature.

Advantageously, it is possible, after application of the composition comprising one or more pigments resulting from one or more 1 ,8-dihydroxynaphthalene derivatives of formula (I) as defined previously, to subject the hair to a heat treatment by heating at a temperature above 40°C, such as between 30°C and 60°C. In practice, this operation may be performed using a hairstyling hood, a hairdryer, an infrared ray emitter or other standard heating appliances.

Use may be made, both as means for heating and smoothing the hair, of a heating iron at a temperature of between 60°C and 220°C and preferably between 120°C and 200°C.

The drying may be performed immediately after the application or after a leave-in time that may range from 1 minute to 30 minutes or after rinsing and optionally shampooing.

Once the optional drying is finished, a rinsing or a final shampooing may optionally be carried out.

According to another particular embodiment of the invention, the method is a method for making up the eyelashes or eyebrows, and applied to which is a mascara makeup composition comprising one or more pigments capable of being obtained by chemical reaction between i) one or more 1 ,8-dihydroxynaphthalene derivatives of formula (I) and ii) one or more chemical oxidizing agents as defined previously; said pigment(s) optionally being combined with one or more coloured mineral fillers as defined previously and/or said pigment(s) optionally being combined with a) one or more hydrophobic film-forming polymers and b) one or more volatile solvents as defined previously.

The application to the eyelashes and eyebrows may be carried out, for example, using a mascara brush and at room temperature. The examples below are intended to illustrate the invention but are in no way limiting.

EXAMPLES

EXAMPLE 1 : Preparation of the pigment of the invention:

1 g of 1 ,8-dihydroxynaphthalene is dissolved in 1 ml of ethanol in a beaker. 9 ml of aqueous sodium hypochlorite (bleach containing 2.5% of active chlorine) are added at room temperature to the solution. A black precipitate rapidly appears. The mixture is kept stirring for 1 hour, then the insoluble black precipitate (pigment) is separated by filtration. It is washed with water. Said precipitate is taken up in ethanol, then filtered again and left to dry in the air. The black pigment of dihydroxynaphthalene is obtained in the form of a powder.

EXAMPLE 2: Dyeing of keratin fibres: A composition below for dyeing keratin fibres (hair) is prepared by mixing 60 g of isopropanol cyclopentadimethylsiloxane sold by Dow Corning under the name DC245 Fluid, 20 g of dimethylpolysiloxane/urea copolymer sold under the reference Wacker-Belsil UD 60 by Wacker, and 20 g of pigment according to the invention obtained in Example 1. 0.5 g of the composition is then applied to a lock of 1 g of clean and dry keratin fibres of natural white (NW) type. After a leave-in time of 5 minutes, the lock is dried with a keratin fibre dryer for 2 minutes.

A dyed lock is obtained for which the keratin fibres are individualized and for which the colour is intense and resistant to successive shampoo washes.

The colour of the hair is also photostable.

EXAMPLE 3: mascara

A mascara of the following composition is prepared by mixing triethanolamine stearate (15.0 g) - beeswax (8.0 g) - paraffin (3.0 g) - rosin (2.0 g) - ozokerite (10.0 g) - propyl parahydroxybenzoate (0.20 g) - methyl parahydroxybenzoate (0.20 g) - gum arabic (0.50 g) - a keratin hydrolysate (1.0 g) - the pigment obtained in Example 1 (5.0 g) and water (qs 100 g).

This mascara in the form of an emulsion is prepared in the following manner:

The waxes are melted. The pigments are incorporated. The aqueous phase containing the gum arabic and the keratin hydrolysate is heated to the same temperature as the waxy phase. The two phases are mixed and stirred vigourously.

The mascara obtained gives the eyelashes a very intense (deep black) and homogeneous colour.