FR2921374A1 - INDOLINIUM THIOL / DISULFIDE DERIVATIVE DYE, TINCTORIAL COMPOSITION COMPRISING THE DYE, METHOD FOR LIGHTENING KERATINIC MATERIALS FROM THAT COLORANT - Google Patents

Abstract

The invention relates to the dyeing of keratin materials using fluorescent dyes derived from indolinium thiols and disulphides.The invention relates to a dyeing composition comprising a thiol or disulfide dye with chromophore derived from indolinium, a process for coloring with lightening effect of keratin fibers such as the hair, using said composition. It likewise relates to new dyes with chromophores derived from indolinium thiol and their uses in the lightening of keratin materials. This composition makes it possible to obtain a coloration with a lightening effect that is particularly tenacious and visible on dark keratinous fibers.

Description

The invention relates to the dyeing of keratin materials using fluorescent dyes derived from indolinium thiols and disulphides, the coloring of keratinous materials being deposited using fluorescent dyes derived from indolinium thiols and disulphides. . It is known to dye keratinous fibers, especially human fibers, by direct dyeing. The method conventionally used in direct dyeing consists in applying to the keratin fibers direct dyes which are colored and dyeing molecules having an affinity for the fibers, allowing them to diffuse and then rinsing the fibers. The direct dyes which are conventionally used are, for example, dyes of the nitrobenzene type, anthraquinone dyes, nitropyridines, dyes of the azo, xanthene, acridine, azine or triarylmethane type. The coloring of the keratinous fibers from these conventional direct dyes does not make it possible to significantly lighten the keratin fibers. The lightening of the color of dark keratin fibers to lighter shades, possibly modifying the shade of these, constitutes an important demand. Conventionally, to obtain a lighter color, a chemical bleaching process is used. This method consists in treating the keratinous fibers, such as the hair, with a strong oxidizing system, generally consisting of hydrogen peroxide associated or not with persalts, most often in an alkaline medium. This bleaching system has the disadvantage of degrading the keratinous fibers, and altering their cosmetic properties. The fibers tend to become rough, more difficult to disentangle and more fragile. Finally, the lightening or the bleaching of keratinous fibers by oxidizing agents is incompatible with the treatments for modifying the shape of said fibers, particularly in the straightening treatments. Another lightening technique consists in applying fluorescent direct dyes to dark hair. This technique, described in particular in the documents WO 03/028685 and WO 2004/091473, makes it possible to respect the quality of the keratinous fiber during the treatment. However, these fluorescent direct dyes do not have a satisfactory tenacity vis-à-vis the external agents. To increase the tenacity of the direct dyes, it is known to use disulfide dyes, in particular dyes with chromophore azo-imidazoliums, in the patent applications WO 2005/097051 or EP 1647580, and dyes with chromophores pyridinium / indolinium-styryls in the applications WO 2006/134043 and WO 2006/136617.

The object of the present invention is to provide novel systems for dyeing keratin materials, in particular human keratinous fibers, in particular the hair, which do not have the drawbacks of existing bleaching processes.

In particular, it is an object of the invention to provide direct dyeing systems which make it possible to obtain lightening effects, in particular on naturally or artificially dark keratin fibers, which are stubborn in the face of successive shampoos, which do not degrade keratin fibers and which do not degrade. do not alter their cosmetic properties. Another object of the invention is to color chromatically and remanent vis-à-vis the external aggressions keratin materials.

This object is achieved with the present invention which relates to a process for dyeing keratin materials, in particular keratinous fibers, in particular human fibers such as the hair, more particularly the dark hair, consisting in applying to the keratin materials a dye composition. comprising, in a suitable cosmetic medium, at least one fluorescent dye derived from indolinium disulfide or thiol, chosen from the dyes of formulas (I), (II) or (III): (I) 2 / Y Si (R 1) p An +, R5 An / L 6 N, N + 1 LI \ \ sS ~ 4 their organic or mineral acid salts, optical isomers, geometric isomers, and solvates such as hydrates; formulas (I), (II) and (III) wherein: - p or p 'represent an integer inclusive between 0 and 4, especially p or p' is 0 or 1; R 'represents a halogen atom, a (C 1 -C 6) alkyl, (C 1 -C 6) alkoxy, 4 (C 1 -C 6) alkylthio, (di) (C 1 -C 6) (alkyl) group; amino, (C 1 -C 6) polyhaloalkyl, hydroxy, (C 1 -C 6) polyhydroxyalkyl, polyhydroxy (C 1 -C 6) alkoxy, cyano, RGC (G ') -, RC (G') - G-, R'S (0) 2-N (R) -, RR'NS (O) 2- with G or G ', identical or different, representing an oxygen atom, sulfur or a group NR', and R and R ', identical or different, representing a hydrogen atom or a (C 1 -C 6) alkyl group; particularly R 'represents is in position 5 and more particularly R' represents a halogen such as chlorine or a (C 1 -C 6) alkoxy group such as methoxy, RR'NS (O) 2- such as Me-S (0) 2-, RR'NC (O) - such as H2N-C (O) -; - R2 and R3, identical or different, represent a group (C, -C6) alkyl particularly R2 and R3 are identical and represent a methyl group; - R4 and R5, represent an alkyl group, or aryl (C1-C6) alkyl, it being understood that R4 represents a bond when the radical - LûSû of the disulfide dye of formula (I) is connected to R4; B represents an optionally substituted aryl or optionally substituted heteroaryl group such as phenyl, naphthyl or indolyl, optionally substituted in particular by one or more groups chosen from (di) (C 1 -C 4) (hydroxyalkyl) amino, (di) (C 1 - C4) (alkyl) amino, hydroxypiperidino, hydroxy and phenyl; L represents an optionally substituted C1-C20 bivalent hydrocarbon chain, optionally interrupted and / or optionally terminated at either of its ends i) by one or more divalent groups or combinations thereof chosen from: ) -; -N + (Ra) (Rb) -, An'-; -O-, -5-, -C (O) -, -S (O) 2-with Ra and Rb, identical or different, selected from hydrogen, (C 1 -C 6) alkyl, hydroxy (C, -C6) alkyl, (di) (C 1 -C 6) (alkyl) amino (C 1 -C 6) alkyl and An- representing an anionic counterion or ii) cationic heterocycle or cationic heteroaryl Het +, An-, with An'-as defined above and Het + representing a heterocycle comprising from 5 to 10 members, saturated or unsaturated, or a heteroaryl comprising from 5 to 10 members such as imidazolium, pyridinium, piperazinium, piperidinium, benzimidazolium; in particular, L represents a (C 1 -C 6) alkylene chain connected to the remainder of the molecule by an NR, -NRC (O) - or C (O) NR- bond; Y represents: i) a hydrogen atom; ii) an alkali metal; iii) an alkaline earth metal; iv) an ammonium group: N + RaRRRYRs, or a phosphonium group: P + RaRRRYRs, with Ra, RR, R7 and R8, identical or different, representing a hydrogen atom or a (C 1 -C 4) alkyl or ) a protecting group of thiol function; - An- represents an anionic counterion; it being understood that: when p is between 2 and 4, the groups R 'are identical or different, when p' is between 2 and 3, the groups R 'are identical or different, when the dye of formula (II) contains a group Y representing a hydrogen atom or an alkali metal, then the L radical can not represent a bivalent hydrocarbon chain at 02-04, the chain L-S- is linked to the indolinium-derived chromophore of formula (I) particularly by A, R4 or B, formulas (I), (II) or (III) may contain other anionic counterions to achieve electroneutrality. Another subject of the invention is a dye composition for the dyeing of keratin fibers with a lightening effect comprising, in a cosmetic medium, at least one fluorescent dye derived from indolinium disulphide or thiol of formulas (I), (II) or ( III) as defined above, and optionally a reducing agent. The subject of the invention is also new fluorescent dyes derived from indolinium disulphides or thiols of formulas (I), (II) or (III) as defined above. The dyeing process according to the invention makes it possible to visibly stain dark keratin materials, in particular dark human keratin fibers, especially dark hair. In addition, the process of the invention makes it possible to obtain hair coloring, without degrading it, remaining with respect to shampoos, common aggressions (sun, perspiration), and hair treatments. The process of the invention also makes it possible to obtain a lightening of keratin materials such as keratinous fibers, particularly dark keratinous fibers and more particularly dark hair. This method also makes it possible to color keratinous fibers in a powerful, low-selectivity and homogeneous manner without observing any significant change over time. Moreover, the dyeing compositions according to the invention are particularly stable during their storage or storage.

For the purposes of the invention, the term "dark keratin material" is understood to mean that which has a luminescence L * encoded in the CIEL * a * b * system, less than or equal to 45 and preferably less than or equal to 40, while also knowing that L * = 0 is equivalent to black and L * = 100 to white. For the purposes of the invention, the term naturally or artificially dark hair, hair whose pitch is less than or equal to 6 (dark blonde) and preferably less than or equal to 4 (chestnut). The lightening of the hair is evaluated by the variation in pitch before and after application of the compound of formulas (I), (II) or (III). The notion of tone is based on the classification of natural nuances, a tone separating each nuance from that which follows it or immediately precedes it. This definition and the classification of natural shades is well known to hair professionals and published in the book Science of hair treatments Charles ZVIAK 1988, Ed Masson, p. 215 and 278. The pitch ranges from 1 (black) to 10 (very light blonde), a unit corresponding to a tone; the higher the number, the clearer the nuance.

An artificially colored hair is a hair whose color has been modified by a coloring treatment, for example a coloration with direct dyes or oxidation dyes. For the purposes of the invention, the term "discolored hair" means hair whose pitch is greater than 6 and preferably greater than 8.

One means for measuring the lightening effect provided to the hair after application of the fluorescent dyes of the invention is to use the hair reflectance phenomenon.

Preferably, the composition should, after application to dark hair, bring to the results below. - We are interested in the reflectance performance of hair when irradiated with visible light in the wavelength range of 400 to 700 nanometers. The reflectance curves are then compared as a function of the wavelength, of the hair treated with the composition of the invention and of the untreated hair. - The curve corresponding to the treated hair must show a reflectance in the wavelength range from 500 to 700 nanometers higher than the curve corresponding to untreated hair. This means that, in the wavelength range of 540 to 700 nanometers, there is at least one range where the reflectance curve corresponding to the treated hair is greater than the reflectance curve corresponding to the untreated hair. The term "superior" means a difference of at least 0.05% reflectance, and preferably at least 0.1%. This does not prevent that there may exist in the wavelength range from 540 to 700 nanometers, at least one range where the reflectance curve corresponding to the treated hair is superimposable, or less than the reflectance curve corresponding to the untreated hair. Preferably, the wavelength where the difference is greatest between the reflectance curve of the treated hair and that of the untreated hair is in the wavelength range of 500 to 650 nanometers, and preferably in the the wavelength range from 550 to 620 nanometers.

Within the meaning of the present invention, and unless a different indication is given: the aryl or heteroaryl radicals or the aryl or heteroaryl part of a radical may be substituted by at least one substituent chosen from: An alkyl radical C1-C16, preferably C1-C8, optionally substituted with one or more radicals selected from hydroxyl, alkoxy C1-C2, (poly) hydroxyalkoxy C2-C4, acylamino, amino substituted with two identical or different C 1 -C 4 alkyl radicals, optionally carrying at least one hydroxyl group, or the two radicals being able to form, with the nitrogen atom to which they are attached, a heterocycle comprising from 5 to 7-membered, preferably 5 or 6-membered, optionally substituted saturated or unsaturated ring optionally comprising another heteroatom identical to or different from nitrogen; A halogen atom such as chlorine, fluorine or bromine; • a hydroxyl group; A C1-C2 alkoxy radical; A C1-C2 alkylthio radical; A C2-C4 (poly) -hydroxyalkoxy radical; An amino radical; A 5- or 6-membered heterocycloalkyl radical which may be substituted with 1 to 3 identical or different groups chosen from hydroxy, amino, (di) alkylamino, hydroxy-C 1 -C 4 alkyl, such as morpholino, (hydroxyethyl) piperazino, (di) ( hydroxy) pyrrolidino (di) (hydroxy) piperidino; A 5- or 6-membered optionally cationic heteroaryl radical, preferentially imidazolium, and optionally substituted with a (C1-C4) alkyl radical, preferably methyl; A phenyl radical; An amino radical substituted with one or two identical or different C1-C6 alkyl radicals optionally carrying at least: i) a hydroxyl group; ii) an amino group optionally substituted by one or two C1-C3 alkyl radicals; optionally substituted, said alkyl radicals being able to form, with the nitrogen atom to which they are attached, an optionally substituted 5 to 7-membered heterocyclic ring, saturated or unsaturated, optionally comprising at least one other heteroatom different from or different from nitrogen, -N (R) -C (O) -R 'in which the radical R is a hydrogen atom, a C 1 -C 4 alkyl radical optionally bearing at least one hydroxyl group and the R' radical is an alkyl radical; C1-C2; R2N-C (O) - in which the radicals R, which may be identical or different, represent a hydrogen atom or a C1-C4 alkyl radical optionally bearing at least one hydroxyl group; • R'S (O) 2 -N (R) - in which the radical R represents a hydrogen atom, a C 1 -C 4 alkyl radical optionally bearing at least one hydroxyl group and the radical R 'represents an alkyl radical; C1-C4i a phenyl radical; R2N-S (O) 2- in which the R radicals, which may be identical or different, represent a hydrogen atom, a C 1 -C 4 alkyl radical optionally bearing at least one hydroxyl group, a carboxylic radical in acid form or salified (preferably with an alkali metal or ammonium, substituted or unsubstituted); • a cyano group; A polyhaloalkyl group comprising from 1 to 6 carbon atoms and from 1 to 6 halogen atoms, which are identical or different, the polyhaloalkyl group is, for example, trifluoromethyl; the cyclic or heterocyclic part of a nonaromatic radical may be substituted by at least one substituent carried by a carbon atom chosen from the groups: hydroxy, (C 1 -C 4) alkoxy, (poly) hydroxyalkoxy (O 2-04) and an alkylthio radical; in C1-C2; RC (O) -N (R ') - in which the radical R' is a hydrogen atom, a C1-C4 alkyl radical optionally bearing at least one hydroxyl group and the radical R is a C1-alkyl radical; -C 2, amino substituted with two identical or different C 1 -C 4 alkyl groups, optionally carrying at least one hydroxyl group; RC (O) -O- in which the radical R is a C 1 -C 4 alkyl radical, amino substituted with one or two identical or different C 1 -C 4 alkyl groups optionally bearing at least one hydroxyl group, said alkyl radicals capable of forming, with the nitrogen atom to which they are attached, a 5- to 7-membered optionally substituted saturated or unsaturated heterocycle optionally comprising at least one other heteroatom which is different from or different from nitrogen; RO-C (O) - in which the R radical is a C 1 -C 4 alkyl radical optionally carrying at least one hydroxyl group; a cyclic, heterocyclic, or nonaromatic portion of an aryl or heteroaryl radical may also be substituted by one or more oxo or thioxo moieties; an aryl radical represents a mono or polycyclic group, condensed or not, comprising from 6 to 22 carbon atoms, and of which at least one ring is aromatic; preferably the aryl radical is a phenyl, biphenyl, naphthyl, indenyl, anthracenyl, or tetrahydronaphthyl; a diarylalkyl radical represents a group comprising, on the same carbon atom of an alkyl group, two identical or different aryl groups, such as diphenylmethyl or 1,1-diphenylethyl; a heteroaryl radical represents a mono- or polycyclic group, fused or otherwise, optionally cationic, comprising from 5 to 22 members, from 1 to 6 heteroatoms chosen from nitrogen, oxygen, sulfur and selenium, and at least one cycle is aromatic; preferably heteroaryl is selected from acridinyl, benzimidazolyl, benzobistriazolyl, benzopyrazolyl, benzo-pyridazinyl, benzoquinolyl, benzothiazolyl, benzotriazolyl, benzoxazolyl, pyridinyl, tetrazolyl, dihydrothiazolyl, imidazopyridinyl, imidazolyl, indolyl, isoquinolyl, naphthoimidazolyle, naphthooxazolyle, naphthopyrazolyle, oxadiazolyl, oxazolyl oxazolopyridyl, phenazinyl, phenoxazolyl, pyrazinyl, pyrazolyl, pyrilyl, pyrazoyltriazyl, pyridyl, pyridinoimidazolyl, pyrrolyl, quinolyl, tetrazolyl, thiadiazolyl, thiazolyl, thiazolopyridinyl, thiazoylimidazolyl, thiopyrylyl, triazolyl, xanthylyl and its ammonium salt; a diheteroarylalkyl radical represents a group comprising, on the same carbon atom of an alkyl group, two heteroaryl groups, which are identical or different, such as difurylmethyl, 1,1-difurylethyl, dipyrrolylmethyl and dithienylmethyl; a cyclic radical is a non-aromatic cycloalkyl radical, mono- or polycyclic, condensed or otherwise, containing from 5 to 22 carbon atoms, which can comprise from 1 to several unsaturations; particularly the cyclic radical is cyclohexyl; - A sterically hindered cyclic radical is a cyclic radical, aromatic or not, substituted or unsubstituted, hindered by steric effect or constraint, comprising from 6 to 14 members, which can be bridged, as sterically hindered radicals include bicyclo [1.1]. Butane, mesylates such as 1,3,5-trimethylphenyl, 1,3,5-triterbutylphenyl, 1,3,5-isobutylphenyl, 1,3,5-trimethylsilylphenyl and adamantyl; a heterocyclic radical or heterocycle is a non-aromatic mono- or polycyclic radical, condensed or not, containing from 5 to 22 members, comprising from 1 to 6 heteroatoms chosen from nitrogen, oxygen, sulfur and selenium; ; an alkyl radical is a C1-C16 hydrocarbon radical, linear or branched, preferably C1-C8; the optionally substituted expression attributed to the alkyl radical, that is to say that said alkyl radical may be substituted by one or more radicals chosen from i) hydroxyl, ii) C 1 -C 4 alkoxy, iii) acylamino, iv) amino optionally substituted by a radical; or two identical or different C 1 -C 4 alkyl radicals, said alkyl radicals being able to form, with the nitrogen atom carrying them, a 5- to 7-membered heterocyl, optionally comprising another heteroatom which may or may not be different from nitrogen; ; v) or a quaternary ammonium group -N + R'R "R" ', M- for which R', R ", R" ', which may be identical or different, represent a hydrogen atom or a C1-C4 alkyl group; or else -N + R'R "R" 'forms a heteroaryl such as imidazolium optionally substituted with a C1-C4 alkyl group, and M- represents the counterion of the corresponding organic, inorganic acid or halide an alkoxy radical is an alkyl-oxy or alkyl-O- radical for which the alkyl radical is a linear or branched C 1 -C 16 hydrocarbon-based radical, preferably a C 1 -C 8 alkyl radical; an alkylthio radical is an alkyl-S radical; - For which the alkyl radical is a hydrocarbon radical, linear or branched C1-C16 preferentially C1-C8, when the alkylthio group is optionally substituted, it implies that the alkyl group is optionally substituted as defined above; an alkylene chain represents a divalent C1-C18 chain; especially C1-C6, more particularly C1-C2 when the chain is linear; optionally substituted by one or more, identical or different, halogen atoms or groups selected from hydroxy, alkoxy, (di) (alkyl) amino, Ra-Za-C (Zb) - with za, Zb, the same or different, representing an oxygen atom, sulfur atom, or a group NRa ', and Ra, representing an alkali metal, a hydrogen atom, or an alkyl group and Ra' representing a hydrogen atom or an alkyl group; a saturated or unsaturated C 1 -C 30 hydrocarbon-based chain, optionally substituted, represents a hydrocarbon-based chain, especially C 1 -C 8, optionally comprising one or more conjugated or unsubstituted 7T double bonds, particularly the hydrocarbon chain is saturated; said chain is optionally substituted by one or more, identical or different, halogen atoms or groups selected from hydroxy, alkoxy, (di) (alkyl) amino, Rb-Zb-C (Z °) - with Zb, Z °, identical or different, representing an oxygen atom, sulfur, or a group NRb ', and Rb, representing an alkali metal, a hydrogen atom, an alkyl group or Rb is absent in which case an anionic counterion belonging in formula (I), (II) or (III) is also absent, and Rb 'represents a hydrogen atom or an alkyl group; the boundaries delimiting the range of a range of values lie within this range of values; an organic or inorganic acid salt is more particularly chosen from a salt derived from i) hydrochloric acid HCl, ii) hydrobromic acid HBr, iii) sulfuric acid H 2 SO 4, iv) alkylsulphonic acids: S (O) 2OH such as methylsulfonic acid and ethylsulfonic acid; v) arylsulfonic acids: Ar-S (O) 2OH such as benzene sulfonic acid and toluene sulfonic acid; (vi) citric acid; vii) succinic acid; viii) tartaric acid; ix) lactic acid, x) alkoxysulfinic acids: Alk-O-S (O) OH such as methoxysulfinic acid and ethoxysulfinic acid; xi) aryloxysulfinic acids such as tolueneoxysulfinic acid and phenoxysulfinic acid; xii) phosphoric acid H3PO4; xiii) acetic acid CH3C (O) OH; xiv) triflic acid CF3SO3H and xv) tetrafluoroboric acid HBF4; an anionic counterion is an anion or an anionic group associated with the cationic charge of the dye; more particularly the anionic counterion is selected from i) halides such as chloride, bromide; ii) nitrates; iii) sulphonates, including C1-C6 alkylsulphonates: Alk-S (O) 2O- such as methylsulphonate or mesylate and ethylsulphonate; iv) arylsulfonates: Ar-S (O) 2O- such as benzenesulphonate and toluenesulphonate or tosylate; v) citrate; vi) succinate; (vii) tartrate; viii) lactate; ix) Alkyl sulfates: Alk-O-S (O) O- such as methysulfate and ethylsulfate; x) arylsulfates: Ar-O-S (O) O- such as benzenesulphate and toluenesulphate; xi) alkoxysulfates: Alk-O-S (O) 2 O- such as methoxy sulfate and ethoxysulfate; xii) aryloxysulfates: Ar-O-S (O) 2 O-, xiii) phosphate; (xiv) acetate; xv) triflate; and xvi) borates such as tetrafluoroborate. ; the solvates represent the hydrates as well as the association with linear or branched C2-C4 linear or branched alcohols such as ethanol, isopropanol and n-propanol.

The fluorescent dyes derived from indolinium disulphides or thiols of formula (I), (II) or (III) as defined above are fluorescent dyes, ie able to absorb in the UV or visible radiation at an Xabs wavelength between 250 and 800 nm and capable of reemitting in the visible range at an emission wavelength Xem between 400 and 800 nm. Preferably, the fluorescent compounds of formulas (I), (II) or (III) of the invention are dyes capable of absorbing in the visible Xabs between 400 and 800 nm and of reemitting in the visible hem between 400 and 800 nm. More preferably, the dyes of formulas (I), (II) or (III) are dyes capable of absorbing at a cell between 420 nm and 550 nm and reemitting in the visible at an Xem of between 5 470 and 600 nm. . The compounds of the invention of formula (II) or (III) contain a SY function which can be in the covalent -S-Y or ionic -S-Y + form depending on the nature of Y and the pH of the medium. One particular mode relates to fluorescent dyes derived from indolinium disulfides or thiols of formula (II) or (III) with Y represents a hydrogen atom, or an alkali metal. Advantageously, Y represents a hydrogen atom. According to another particular embodiment of the invention, in the formula (II) or (III), Y is a protective group known to those skilled in the art such as those described in the books Protective Groups in Organic Synthesis, T. W, Greene, John Willey & Sons ed., NY, 1981, pp.193-217; Protecting Groups, P. Kocienski, Thieme, 3rd ed., 2005, chap. 5. Particularly when Y represents a protecting group of the thiol function, Y is chosen from the following radicals: (C 1 -C 4) alkylcarbonyl; (C 1 -C 4) alkylthiocarbonyl; (C 1 -C 4) alkoxycarbonyl; (C 1 -C 4) alkoxythiocarbonyl; (C 1 -C 4) alkylthiothiocarbonyl; ^ (di) (C1-C4) (alkyl) aminocarbonyl; 25 (di) (C1-C4) (alkyl) aminothiocarbonyl; Arylcarbonyl as phenylcarbonyl; aryloxycarbonyl; Aryl (C1-C4) alkoxycarbonyl; (Di) (C1-C4) (alkyl) aminocarbonyl as dimethylaminocarbonyl; (C 1 -C 4) (alkyl) arylaminocarbonyl; carboxy; • S03; M + with M 'representing cationic counterion as an alkali metal such as sodium or potassium, or else An- of formula (II) or (III) and M' are absent; Optionally substituted aryl such as phenyl, dibenzosuberyl, or 1,3,5-cycloheptatrienyl; optionally substituted heteroaryl; of which especially cationic or non-cationic heteroaryl comprising from 1 to 4 following heteroatoms: i) monocyclic with 5, 6 or 7 members such as furanyl or furyl, pyrrolyl or pyrryl, thiophenyl or thienyl, pyrazolyl, oxazolyl, oxazolium, isoxazolyl, isoxazolium, thiazolyl, thiazolium, isothiazolyl, isothiazolium, 1,2,4-triazolyl, 1,2,4-triazolium, 1,2,3-triazolyl, 1,2,3-triazolium, 1,2, 4-oxazolyl, 1,2,4-oxazolium, 1,2,4-thiadiazolyl, 1,2,4-thiadiazolium, pyrylium, thiopyridyl, pyridinium, pyrimidinyl, pyrimidinium, pyrazinyl, pyrazinium, pyridazinyl, pyridazinium, triazinyl, triazinium, tetrazinyl, tetrazinium, azepine, azepinium, oxazepinyl, oxazepinium, thiepinyl, thiepinium, imidazolyl, imidazolium; ii) 8 to 11-membered bicyclic compounds such as indolyl, indolinium, benzoimidazolyl, benzoimidazolium, benzoxazolyl, benzoxazolium, dihydrobenzoxazolinyl, benzothiazolyl, benzothiazolium, pyridoimidazolyl, pyridoimidazolium, thienocycloheptadienyl, these mono or bicyclic groups being optionally substituted by one or more groups such as C 1 -C 4) alkyl as methyl, or polyhalo (C 1 -C 4) alkyl as trifluoromethyl; iii) or tricyclic ABC according to: wherein the two rings A, C optionally comprise a heteroatom, and the ring B is a 5-, 6- or 7-membered particularly 6-membered ring and contains at least one heteroatom such as pyperidyl, pyranyl; optionally substituted heterocycloalkyl, optionally cationic, the heterocycloalkyl group represents in particular a saturated or partially saturated monocyclic group with 5, 6 or 7 members comprising 1 to 4 heteroatoms chosen from oxygen, sulfur and nitrogen, such as di / tetrahydrofuranyl, di / tetrahydrothiophenyl, di / tetrahydropyrrolyl, di / tetrahydropyranyl, di / tetra / hexa-hydrothiopyranyl, dihydropyridyl, piperazinyl, piperidinyl, tetramethylpiperidinyl, morpholinyl, di / tetra / hexahydroazepinyl, di / tetrahydropyrimidinyl these groups being optionally substituted by one or more groups such as (C1-C4) alkyl, oxo or thioxo; or the heterocycle represents the following group: R '\ R'g R'h N i ~ CR eR f ~ v R'd An "in which R' °, R'g, R'e, R'f, R and R ', which are identical or different, represent a hydrogen atom or a group (C1-C4) alkyl, or else two groups R'g with R'h and / or R'e with R'f form a an oxo or thioxo group, or else R'g with R'e together form a cycloalkyl, and v represents an integer inclusive between 1 and 3, preferably R '° to R'h represent a hydrogen atom, and An "' represents a counterion; isothiouronium; ^ -C (NR '° R'd) = N + R'eR'f; With R '°, R'g, R'e and R'f, which are identical or different, represent a hydrogen atom or a (C 1 -C 4) alkyl group, preferentially R' ° to R 'f represent a hydrogen atom, and An - represents a counter-ion; isothiourea; -C (NR '° R'd) = NR'e; with R' °, R'g and R'e are as defined; previously; 15 (di) aryl (C1-C4) alkyl optionally substituted such as 9-anthracenylmethyl, phenylmethyl or diphenylmethyl optionally substituted with one or more groups chosen in particular from (C1-C4) alkyl, (C1-C4) alkoxy as methoxy, hydroxy, alkylcarbonyl, (di) (C.sub.1 -C.sub.4) (alkyl) amino such as dimethylamino; optionally substituted optionally substituted C.sub.1 -C.sub.18 di (di) heteroaryl (C.sub.1 -C.sub.4) alkyl, the heteroaryl group is especially, cationic or otherwise, monocyclic, comprising 5 or 6 members and from 1 to 4 heteroatoms selected from nitrogen, oxygen and sulfur, such as pyrrolyl, furanyl, thiophenyl, pyridyl, pyridyl N-oxide groups such as e 4-pyridyl or 2-pyridyl-N-oxide, pyrylium, pyridinium, triazinyl, optionally substituted with one or more groups such as alkyl particularly methyl, advantageously (di) heteroaryl (C 1 -C 4) alkyl is (di) heteroarylmethyl or (di) heteroarylethyl; Wherein R ', R 2 and R 3, which may be identical or different, represent a halogen atom or a group selected from: - (C 1 -C 4) alkyl; - (C 1 -C 4) alkoxy; optionally substituted aryl such as phenyl optionally substituted with one or more groups such as (C 1 -C 4) alkyl, (C 1 -C 4) alkoxy, hydroxy; - optionally substituted heteroaryl such as thiophenyl, furanyl, pyrrolyl, pyranyl, pyridyl, optionally substituted with a (C 1 -C 4) alkyl group; - P (Z ') R''R'2R'3 with R'1, and R'2 identical or different represent a hydroxyl group, (C1-C4) alkoxy or alkyl, R'3 represents a hydroxyl group or ( C 1 -C 4) alkoxy, and Z 'represents an oxygen or sulfur atom; Cyclic sterically hindered; and optionally substituted alkoxyalkyl such as methoxymethyl (MOM), ethoxyethyl (EOM) and isobutoxymethyl. According to a particular embodiment, the protected thiol dyes of formula (II) or (III) comprise a cationic aromatic 5- or 6-membered monocyclic moiety Y i) heteroaryl comprising from 1 to 4 heteroatoms selected from oxygen, sulfur and nitrogen, such as oxazolium, isoxazolium, thiazolium, isothiazolium, 1,2,4-triazolium, 1,2,3-triazolium, 1,2,4-oxazolium, 1,2,4-thiadiazolium, pyrylium, pyridinium, pyrimidinium, pyrazinyl, pyrazinium, pyridazinium, triazinium, tetrazinium, oxazepinium, thiepinyl, thiepinium, imidazolium; ii) cationic 8 to 11-membered bicyclic heteroaryl such as indolinium, benzoimidazolium, benzoxazolium, benzothiazolium, these mono or bicyclic heteroaryl groups being optionally substituted with one or more groups such as alkyl as methyl, or polyhalo (C 1 -C 4) alkyl as trifluoromethyl; iii) or heterocyclic according to: R, d An in which R '° and R'd, identical or different, represent a hydrogen atom or a (C 1 -C 4) alkyl group; preferentially R '° to R'd represent a (C 1 -C 4) alkyl group such as methyl; and Y is a counterion, especially Y is a group selected from oxazolium, isoxazolium, thiazolium, isothiazolium, 1,2,4-triazolium, 1,2,3-triazolium, 1,2,4-oxazolium, , 2,4-thiadiazolium, pyrylium, pyridinium, pyrimidinium, pyrazinium, pyridazinium, triazinium and imidazolium, benzoimidazolium, benzoxazolium, benzothiazolium, these groups being optionally substituted by one or more (C1-C4) alkyl groups, especially methyl. an alkali metal or a protecting group such as: - (C 1 -C 4) alkylcarbonyl such as methylcarbonyl or ethylcarbonyl; - arylcarbonyl such as phenylcarbonyl; - (C 1 -C 4) alkoxycarbonyl; aryloxycarbonyl; -aryl (C 1 -C 4) alkoxycarbonyl; - (di) (C1-C4) (alkyl) aminocarbonyl as dimethylaminocarbonyl; - (C1-C4) (alkyl) arylaminocarbonyl; - optionally substituted aryl such as phenyl; - monocyclic 5- or 6-membered heteroaryl such as imidazolyl or pyridyl - heteroa cationic monocyclic ring with 5, 6 members such as pyrylium, pyridinium, pyrimidinium, pyrazinium, pyridazinium, triazinium, imidazolium; these groups being optionally substituted by one or more, identical or different, (C 1 -C 4) alkyl groups such as methyl; 8 to 11-membered cationic bicyclic heteroaryl such as benzoimidazolium, or benzoxazolium; these groups being optionally substituted by one or more, identical or different, (CIC4) alkyl groups such as methyl; cationic heterocycle of the following formula: isothiouronium; -C (NH2) = N + H2; - isothiourea; --C (NH2) = NH; - S03-, M + with M + representing a cationic counterion as an alkali metal such as sodium or potassium, or then An- of the formula (II) or (III) and M + are absent. According to one particular embodiment of the invention, the fluorescent dyes of the invention are disulfide dyes of formula (1). In particular, the disulfide fluorescent dyes of formula (I) of the invention are chosen from those of formula (Ia), (Ib) and (Ie): ## STR1 ## Embedded image (CH 2) n (CH 2) 7 X 1 B (la) 6 1 (R) p / SiO 2 Ta (CH (CH) a T 2) m2a 2 R / N (CH) (CH) N + j 2n 2, s A ( 1b) A-1 2 R nn BB / Si / Ta (CH 2) m (CH 2) aTa X (CH 2) n (CH 2) 7X 6 N R 4 / An (R 1) p. formulas (Ia), (Ib) and Oc) in which: - p, p ', R' to R4, B and An- are as defined above; n and m, identical or different, represent an integer inclusive between 1 and 6 with the sum of n + m which is between 2 and 4 inclusive, particularly 2 or 3 for (1b); X represents a radical chosen from: -G-, -G'-C (G) - and -C (G) -G'-, with G and G ', which may be identical or different, representing an oxygen atom, sulfur, or NR, with R representing a hydrogen atom or a (C1-C6) alkyl group, advantageously X represents a group -NR-, -NR-CO-, -C (O) -NR-, -S (O) 2-, -S (O) 2-NR-; or -NR-S (O) 2-, or -NR-; especially X of the formula (Ia) is attached at position 5 to A or the X of the formula (Ia) is in para of B when B represents a phenyl group; Ta represents a covalent bond 6, a group ùN (R'a) -; -N + (R'a) (R'b) -, An-; - C (O) -N (R'a) - or -N (R'a) -C (O) -, or a divalent cationic heteroaryl comprising from 5 to 7 members, such as imidazolium, with R'a, R b, identical or different, representing a hydrogen atom, a (C1-C4) alkyl radical, An- representing an anionic counterion; especially Ta represents -C (O) -N (R'a) - and -N (R'a) -C (O) -.

By way of example, mention may be made of the following fluorescent dyes of formula (Ia), (Ib) and Oc): Me NN 2 An Me 1 Cl 2 H2N N Me NH2 3 Me Me N ~ S \ S Me u Me 0 2 Yield 4 6 SOZNHZ 7 8 OMe MeO 9 HO 10 SOZMe 11 19 MeO OH OMe 12 NH 2 An- HO Me 13 N / A Me MH Nù / sùS, / Me Me S / 02 Me Me 2 An Me 14 HS OH HS ## STR5 ## with An-, identical or different, representing an anionic counterion. For all the examples of embodiments of preparation which follow new fluorescent dyes derived from indolinium disulfide or thiol of formula (I) to (III), those skilled in the art know how to protect beforehand the reactive functions such as the ketone functions and then deprotect them for the purposes of the synthesis reaction, by the known conventional methods of protection / deprotection as those described in the works cited above of TW Greene John Willey & Sons ed., NY, 1981, or P. Kocienski Protecting Groups, P. Kocienski, Thieme, S ed., 2005.

The protected thiol fluorescent dyes of formula (II-Y) or (III-Y) can be synthesized in two stages. The first step of preparing the unprotected thiol dye (II-H) or (III-H) according to methods known to those skilled in the art such as Thiols and organic Sulfides, Thiocyanates and Isothiocyanates, organic, Ullmann's Encyclopedia , Wiley-VCH, Weinheim, 2005. And the second step of protecting the thiol function according to conventional methods known to those skilled in the art to lead to protected thiol dyes of formula (II-Y) or (III-Y). By way of example, to protect the thiol function of the thiol dye, the methods of Protective Groups in Organic Synthesis, T.W. Greene, John Willey & Sons, Ed., NY, 1981, pp.193-217; Protecting Groups, P. Kocienski, Thieme, 3rd ed., 2005, chap. 5. We can illustrate this method by the method consisting of i) generating fluorescent dyes derived from indolinium thiol of formula (II-H) or (III-H) by reduction of a fluorescent dye derived from indolinium to two chromophores , having a disulfide function -SS-such that (I ') and ii) to be protected according to conventional methods said thiol function of (II-H) or (III-H) with the reagent 7 Y'R to access the thiol dyes protected of formula (I '). The thiol compound (II-H) or (III-H) may also be metallized with an alkali metal or alkaline earth metal Met * to yield the thiolate fluorescent dye of formula (II-Met) or (III-Met). 2 2 2 (II-H) (III-H) 7 y 'R - Y'H (I IY) (II-H) metallation (III-H) metallation (II-Met) Met * (III-Met) R5 with Y 'representing a protecting group of thiol function; Met * represents an alkali metal or an alkaline earth metal, particularly sodium or potassium, it being understood that when the metal is an alkaline earth metal 2 thiolate-functional chromophores -S-may be associated with 1 Metal2 +; and with R 'to R5, A, B, An-, L and p, are as previously defined; Y 'represents a protecting group of thiol function; and R represents a leaving group nucleofuge, such as mesylate, tosylate, triflate or halide. Indolinium styryl thiol styryl-derived fluorescent dyes formed which are converted to Y-protected thiols fluorescent dyes by protection of the HSH thiol using conventional protecting groups. Fluorescent dyes derived from indolinium styryl thiols are metallated using also conventional methods known to those skilled in the art such as those described in Advanced Organic Chemistry, Reactions, Mechanisms and Structures, J. March, 4th Ed, John Willey & Sons , NY, 1992.

According to another possibility, a thiol compound protected by a protecting group Y 'as defined previously prepared can be reacted according to one of the procedures described in the works cited above, said protected thiol compound comprising at least one nucleophilic function with a sufficient amount , preferably equimolar, of a chromophore j or a, derived from indolinium styryl, and which comprises a function E / SY 'X (/ Cl2) (CH2) m, (R1) p. (III'-Y) with R1 to R5, A, B, An- and p, are as previously defined; m 'and n' are integers inclusive between 1 and 6 with m '+ n' is an integer of 2 to 6, where Wu is a nucleophilic group; E representing an electrophilic group; and 1 representing the bond generated after nucleophilic attack on the electrophile. By way of example, the covalent E bonds that can be generated are listed in the electrophile dye preparation below to form a covalent E bond; of formula (II'-Y) and (III'-Y): (R 1) p B Nuù (CH 2) SSY 'SY' / E / N (CH 2) n, (CH 2) m,

An / (Ir-Y) BL 1L the table below from condensation of electrophiles with nucleophiles: Electrophilic E Nucleophiles ~ u Covalent bonds E Activated esters * Amines Carboxamides Acyl azides ** Amines Carboxamides Acyl halogenides Amines Carboxamides Acyl halides Alcohols Esters Acyl cyanides Alcohols Esters Acyl cyanides Amines Carboxamides Alkyl halides Amines Alkylamines Halides of alkyls Carboxylic acids Esters Halides of alkyls Thiols Thioesters Halides of alkyls Alcohols Ethers Sulphonic acids and their salts Thiols Thioethers Sulfonic acids and their salts Carboxylic acids Esters Sulfonic acids and their salts Alcohols Ethers Anhydrides Alcohols Esters 25 Anhydrides Amines Carboxamides Halides of aryls Thiols Thioethers Halides of aryl Amines Arylamines Aziridines Thiols Thioethers Carboxylic Acids Amines Carboxamides Carboxylic Acids Alcohols Esters Carbodiimides Carboxylic Acids N-Acyl urea Diazoalkanes Carboxylic Acids Esters Epoxides Thiols Thioethers Haloacetamides Thiols Thioethers Esters imides Amines Amidines Isocyanates Amines Ureas Isocyanates Alcohols Urethanes Isothiocyanates Amines Thioureas Maleimides Thiols Thioethers Sulphonic esters Amines Alkylamines Sulphonic esters Thiols Thioethers Sulphonic esters Carboxylic acids Esters Sulphonic esters Alcohols Ethers Sulphonyl halides Amines Sulfonamides * Activated esters of the general formula ùCO-Part with Part representing a leaving group such as oxysuccinimidyl, oxybenzotriazolyl, optionally substituted aryloxy; ** Acyl azides can rearrange to give isocyanates.

An alternative to this method is to use a chromophore derived from indolinium styryl having an electrophilic acrylate function (-OCO-C = C-) on which an addition reaction is carried out which will generate an L bond. A reagent may also be used. thiol (a): Y'-SH comprising a group Y 'as defined previously, whose nucleophilic function SH can react on the carbon atom of the radical L in alpha of the halogen atom carried by a chromophore derived from indolinium styryl of or (a-1), to yield protected thiol dye of formula (II-Y) or (III-Y) as defined above: ## STR1 ## al) with R 'to R5, A, B, An-, L, p, (II-Y) and (III-Y) are as defined above, and Hal represents a nucleofugal halogen atom such as bromine, iodine or chlorine. More particularly, it will be possible to substitute a nucleofugal leaving group with a thiourea group (S = C (NRR) NRR) to generate the isothiouroniums. For example from chromophores j or (a'1) as defined above if the thiourea group is a thioimidazolium (Ji), to give the dye S-protected by an imidazolium group (11 "-Y) or (111" - Y): SH R'c, N. "(F` - N _R'd n An - HHaI (aï) R'cN LùS \ N + An N R'd R'cN with f, (a'1), R R'd, R 'to R5, A, B, L, p, Hal and An- are as previously defined, Another variant may provide access to the compound (II "-Y) or (III" -Y) from cyclic thiourea of imidazoline type (b '), followed by the alkylation of said imidazole using R'd-Gp with Gp leaving group such as chloride, bromide, tosylate, mesylate: N R1) p An LsS Alkylation N + R'd-Gp R'cN Nù) N \ LùS N Gp N + R 'a R'CN SH ~ N - HHaI R'cN R'cN N \ N.ù) B + N \ ## STR1 ## wherein R1, R'd-Gp R5 with j, (a'1), R1, R'd, R1 to R5, A, B, L, p, and Gp, are as defined previously.

An alternative is to use in place of the halide comprising the fluorescent chromophore j or (a'1) a chromophore comprising another type of nucleofuge such as tosylate, mesylate. According to another possibility, certain protected thiol dyes (II'-Y) or (III'-Y) can be obtained by reacting a protected thiol compound with a compound carrying two carboxylic acid functional groups activated according to conventional methods (for example reaction with a carbodiimide or with thionyl chloride). The resulting product is then reacted with a chromophore or (c1 derived from indolinium styryl, whose ketone functions are optionally protected beforehand as seen above, and carrying a nucleophilic function, for example of the primary amine type or secondary, or aliphatic alcohol type R5 B - (CH2) m, SY '(III'-Y) L11 with R' to R5, A, B, An-, L, p, n ', m', E A further variant is to use a thiolactone derivative from particular nucleophilic chromophores jj and c 'to yield derivatives (II'). -H) or (III'-H) comprising a linker L interrupted by an amide function as represented by the scheme below: (R1) PG 'N (CH2) n, iCH2) m, An SH B (II ## STR2 ## wherein R 'to R 5, B, An-, L, p, n ', m' are as defined above, G 'representing an oxygen atom, sulfur atom or an NR' group with R representing a hydrogen atom or an alkyl radical, and R representing a hydrogen atom, a C1-C4 alkyl, C1-C4 hydroxyalkyl or a (C1-C4) alkyl radical. The thiolactone derivative is preferably chosen with m '= 3 and G' represents an oxygen atom. The drifts (II'-H) or (III'-H) with free SH function can then be protected or metallized as seen previously. According to another possibility, the fluorescent dyes derived from indolinium styryl thiols of formula (II) or (III) according to the invention can be obtained by reaction of a compound comprising a thiol group optionally protected by Y 'as defined previously and an electrophilic group with an aryl or heteroaryl derivative comprising an electrophilic group. For example, an aldehyde or a thioaldehyde may be condensed when G 'represents an oxygen atom or sulfur with an activated methylene derivative such as the fuzzy methylindolinium derivative (f') to generate an ethylene> C bond = C <. This reaction is commonly known as Knoevenagel condensation: reference may be made to Advanced Organic Chemistry, Reactions, Mechanisms and Structures, J. March, 4th Ed, John Willey & Sons, 1992, or TW Greene Protective Groups in Organic Synthesis, for have more details on the operating conditions used for the processes mentioned above. The fluorescent dyes derived from protected indolinium styryl thiols can be deprotected by conventional routes such as those described in the books Protective Groups in Organic Synthesis, T. W. Greene, John Willey & Sons ed., NY, 1981; Protecting Groups, P. Kocienski, Thieme, S ed., 2005. The starting reagents are commercial or accessible by conventional methods known to those skilled in the art. By way of example, mention may be made of the synthesis of the dye (I), and subsequently the reagents (I ') or (I "), from 2 equivalents of indolinium derivative (α1 and one equivalent of disulfide reagent 2 comprising two electrophilically functional aryl or heteroaryl B such as aldehyde, thioaldehyde or an activated methylene disulfide indolinium reagent 3 comprising with two equivalents of aryl-derived electrophilic reactant or heteroaryl (g '), to drive Knoevenagel by double condensation to indolinium derivatives of styryl disulfides, with R 'to R 5, B, An-, L, p, G', (II-Y) and (III-Y) are as defined above (II-Y) (III-Y) G 'G' 2 (1) Knoevenagel - 2 H2G 3 2 ùL S Knoevenagel - 2 H2G with R 'to R4, B, An-, L, p, G 'and (I) are as defined above.

Another subject of the invention relates to a composition for the dyeing of keratin fibers with a lightening effect comprising, in a cosmetic medium, at least one fluorescent dye derived from indolinium disulfide, thiol or protected thiol of formulas (I), (II) or (III) as defined above. In addition to the presence of at least one fluorescent dye of formula (I), (II) or (III), the composition of the invention may also contain a reducing agent.

This reducing agent may be chosen from thiols, for example cysteine, homocysteine, thiolactic acid, the salts of these thiols, phosphines, bisulfite, sulphites, thioglycolic acid and its esters, especially the glycerol monothioglycolate, and thioglycerol. This reducing agent may also be chosen from borohydrides and their derivatives, for example salts of borohydride, cyanoborohydride, triacetoxyborohydride, trimethoxyborohydride: sodium, lithium, potassium, calcium, quaternary ammonium salts (tetramethylammonium, tetraethylammonium, tetrapropylammonium tetra-n-butylammonium, benzyltriethylammonium); catechol borane. The dye composition useful in the invention generally contains an amount of dye of formula (I), (II) or (III) between 0.001 and 50% relative to the total weight of the composition. Preferably, this amount is between 0.005 and 20% by weight and even more preferably between 0.01 and 5% by weight relative to the total weight of the composition. The dye composition may further contain additional direct dyes. These direct dyes are, for example, chosen from neutral, acidic or cationic nitro-benzene direct dyes, neutral azo, acid or cationic direct dyes, tetraazapentamethine dyes, neutral or acidic or cationic quinone dyes, in particular neutral anthraquinone dyes and direct azine dyes. , triarylmethane direct dyes, indoamine direct dyes and natural direct dyes. Among the natural direct dyes that may be mentioned are lawsone, juglone, alizarin, purpurin, carminic acid, kermesic acid, purpurogalline, protocatechaldehyde, indigo, isatin, curcumin, spinulosin, apigenidine. It is also possible to use the extracts or decoctions containing these natural dyes, and in particular poultices or extracts made from henna. The dye composition may contain one or more oxidation bases and / or one or more couplers conventionally used for dyeing keratinous fibers. Among the oxidation bases that may be mentioned are para-phenylenediamines, bisphenylalkylenediamines, para-aminophenols, bis-para-aminophenols, ortho-aminophenols, heterocyclic bases and their addition salts. Among these couplers, mention may notably be made of meta-phenylenediamines, meta-aminophenols, meta-diphenols, naphthalenic couplers, heterocyclic couplers and their addition salts. The coupler or couplers are each generally present in an amount of between 0.001 and 10% by weight of the total weight of the dyeing composition, preferably between 0.005 and 60/0.

The oxidation base (s) present in the dyeing composition are in general each present in an amount of between 0.001% and 10% by weight relative to the total weight of the dyeing composition, preferably between 0.005% and 6% by weight. In general, the addition salts of the oxidation bases and couplers that can be used in the context of the invention are chosen especially from the addition salts with an acid such as hydrochlorides, hydrobromides, sulphates, citrates, succinates, tartrates, lactates, tosylates, benzenesulfonates, phosphates and acetates and addition salts with a base such as alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, ammonia, amines or alkanolamines. The medium suitable for dyeing, also called dyeing medium, is a cosmetic medium generally consisting of water or a mixture of water and at least one organic solvent. As organic solvent, there may be mentioned for example lower alkanols C1-C4, 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, as well as aromatic alcohols such as benzyl alcohol or phenoxyethanol, and mixtures thereof. The solvents other than water, when they are present, are preferably present in proportions preferably of between 1 and 40% by weight approximately relative to the total weight of the dyeing composition, and even more preferably between 5 and 30. about% by weight. The solvents including water are preferably present in proportions preferably of between 1 and 99% by weight approximately relative to the total weight of the dye composition, and even more preferably between 5 and 95% by weight approximately. The dye composition may also contain various adjuvants conventionally used in compositions for dyeing hair, such as anionic, cationic, nonionic, amphoteric, zwitterionic surfactants or mixtures thereof, anionic, cationic, nonionic, amphoteric and zwitterionic polymers. or mixtures thereof, inorganic or organic thickeners, and in particular anionic, cationic, nonionic and amphoteric polymeric associative thickeners, antioxidants, penetrating agents, sequestering agents, perfumes, buffers, dispersing agents, conditioning agents such as, for example, volatile or non-volatile silicones, modified or otherwise, such as aminosilicones, film-forming agents, ceramides, preserving agents, opacifying agents, conductive polymers. The adjuvants above are generally present in an amount for each of them between 0.01 and 20% by weight relative to the weight of the composition. Of course, one skilled in the art will take care to choose this or these optional additional compounds in such a way that the advantageous properties intrinsically attached to the dyeing composition according to the invention are not, or not substantially, impaired by the or the additions envisaged. The pH of the dyeing composition is generally between 3 and 14 approximately, and preferably between 4 and 10 approximately. It can be adjusted to the desired value by means of acidifying or alkalizing agents usually used for dyeing keratin fibers or else using conventional buffer systems. Among the acidifying agents, mention may be made, by way of example, of mineral or organic acids such as hydrochloric acid, orthophosphoric acid, sulfuric acid, carboxylic acids such as acetic acid, tartaric acid, citric acid, lactic acid, sulphonic acids. Among the alkalinizing agents that may be mentioned, by way of example, are ammonia, alkaline carbonates, alkanolamines such as mono-, di- and triethanolamines and their derivatives, sodium or potassium hydroxides and following formula (y): RR / az N-Wa-N-Ra4 Rai (Y) in which Wa is a propylene residue optionally substituted by a hydroxyl group or a C1-C4 alkyl radical; Ra1, Ra2i Ra1 and Ra4, which may be identical or different, represent a hydrogen atom, a C1-C4 alkyl radical or a C1-C4 hydroxyalkyl radical.

The dye composition may be in various forms, such as in the form of liquid, cream, gel, or in any other form suitable for dyeing keratinous fibers, and in particular hair. Another subject of the invention is a process for dyeing keratinous substances, in particular keratinous fibers such as dark hair, which consists in applying to the keratin materials a dyeing composition comprising in a cosmetic medium at least one fluorescent dye derived indolinium disulfide, thiol or protected thiol of formula (I), (II) or (III) as defined above. According to a particular embodiment in the method of the invention, the reducing agent may be applied pre-treatment before application of the composition containing at least one fluorescent dye derived from indolinium disulfide, thiol or protected thiol of formula ( I), (II) or (III). This pretreatment may be of short duration, especially from 1 second to 30 minutes, preferably from 1 minute to 15 minutes with a reducing agent as mentioned above.

According to another method, the composition comprising at least one fluorescent dye derived from indolinium disulfide, thiol or protected thiol of formula (I), (II) or (III) and also contains at least one reducing agent as defined above. This composition is then applied to the hair. When a fluorescent dye derived from indolinium thiol or protected thiol of formula (II) or (III) comprises a group Y protecting the thiol function, the process of the invention may be preceded by a deprotection step intended to restore in-situ the SH function. By way of example, it is possible to deprotect the SY function of the dyes of the invention with the protective group by adjusting the pH as follows: Y: alkylcarbonyl deprotection protecting group, pH> 9 arylcarbonyl, pH> 9 alkoxycarbonyl, pH> 9 aryloxycarbonyl, pH> 9 arylalkoxycarbonyl pH> 9 (di) (alkyl) aminocarbonyl, pH> 9 (alkyl) arylaminocarbonyl pH> 9 optionally substituted aryl such as phenyl, pH> 9 monocyclic 5-, 6- or 7-membered heteroaryl such as oxazolium; pH> 9 bicyclic 8 to 11-membered bicyclic heteroaryl such as benzoimidazolium, pH> 9 or benzoxazolium The deprotection step can also be carried out during a pretreatment stage of the hair, such as, for example, the hair reduction pretreatment. According to one variant, the reducing agent is added to the dyeing composition containing at least one fluorescent dye derived from indolinium disulfide, thiol or protected thiol of formula of formula (I), (II) or (III) at the time of the employment. Advantageously, the reducing agent is added to the dyeing composition containing at least one fluorescent dye of formula (I). According to another method, the composition comprising at least one fluorescent dye derived from indolinium disulfide, thiol or protected thiol of formula (I), (II) or (III) also contains at least one reducing agent as defined above. This composition is then applied to the hair. In particular, the composition containing at least one dye of formula (I) also contains a reducing agent. According to another variant, the reducing agent is applied in post-treatment, after the application of the composition containing at least one fluorescent dye derived from indolinium disulfide, thiol or protected thiol of formula (I), (II) or ( III). Particularly when the composition contains at least one fluorescent dye of formula (I), the reducing agent is applied in post-treatment. The duration of the post-treatment with the reducing agent may be short, for example from 0.1 second to 30 minutes, preferably from 1 minute to 15 minutes, with a reducing agent as described above. According to a particular embodiment, the reducing agent is a thiol or borohydride type agent as described above. A particular embodiment of the invention relates to a process in which a fluorescent dye derived from indolinium thiol or protected thiol of formula (II) or (III) can be applied directly to hair without reducing agents, free of pre- or post- treatment reducers. A treatment with an oxidizing agent may optionally be associated. Any type of conventional oxidizing agent may be used in the art. Thus, it may be chosen from hydrogen peroxide, urea peroxide, alkali metal bromates, persalts such as perborates and persulphates, as well as the enzymes among which may be mentioned peroxidases, oxides, 2-electron reductases such as uricases and 4-electron oxygenases such as laccases. The use of hydrogen peroxide is particularly preferred. The duration of the possible post-treatment with an oxidizing agent is between 1 second and 40 minutes. Preferably between 1 and 10 minutes. The application of the dye composition according to the invention is generally carried out at room temperature. It can however be carried out at temperatures ranging from 20 to 180 ° C. The invention also relates to a multi-compartment device or "kit" of dyeing in which a first compartment contains a dye composition comprising at least one fluorescent dye derived from indolinium disulfide, thiol or protected thiol of formula (I), ( II) or (III) and a second compartment contains a reducing agent capable of reducing the disulfide functions of the keratinous fibers and / or the indolinium fluorescent dye of formula (I). One of these compartments may further contain one or more other dyes of direct dye type or oxidation dye. It also relates to a multi-compartment device in which a first compartment contains a dye composition comprising a fluorescent dye derived from indolinium disulfide, thiol or protected thiol of formula (I), (II) or (III); a second compartment contains a reducing agent capable of reducing the disulfide bond of the keratinous fibers and / or the indolinium disulfide-derived fluorescent dye of formula (I); a third compartment contains an oxidizing agent.

Alternatively, the dyeing device contains a first compartment containing a dyeing composition which comprises at least one protected indolinium thiol-derived fluorescent dye of formula (II) or (III), a second compartment containing an agent capable of deprotecting the protected thiol for liberate the thiol, and optionally a third compartment comprising an oxidizing agent.

Each of the above-mentioned devices may be equipped with means for delivering the desired mixture onto the hair, for example such as the devices described in patent FR 2 586 913. The following examples serve to illustrate the invention without however to be limiting in nature. The dyes of the examples below have been fully characterized by standard spectroscopic and spectrometric methods.

EXAMPLES Example 1 Synthesis of 2,2 '- {disulfanediylbis [ethane-2,1-diyl (methylimino) -4,1-phenylene-ethen-2,1-diyl]} bis di (1,3,3-dichloride) trimethyl-3H-indolium [1] Synthesis scheme: ## STR1 ## [1] Procedure: Step 1: 4,4 '- {disulfanediylbis [ethane-2,1-diyl (methylimino)]} dibenzaldehyde 82.3 g of phosphorus oxychloride are added to 500 ml of DMF at 0 ° C. After 30 minutes of stirring at 0 ° C. A solution of 47 g of N, N '(disulfanediyldiethane-2,1-diyl) bis (N-methylaniline) is added dropwise The mixture is stirred for 90 min at 0 ° C. and then 75 min at 10 ° C. C. and 105 min at 40 ° C. It is then poured into 2.5 L of ice water, 700 ml of 5N sodium hydroxide are added The yellow precipitate obtained is filtered on celite, solubilized in 200 ml of dichloromethane and the solution obtained is washed with 200 ml of saturated aqueous sodium chloride solution, after drying over magnesium sulfate and evaporation. dichloromethane, the yellow residue (80 g) is purified by chromatography on silica gel. After drying, a light yellow powder is collected. The analyzes indicate that the product conforms to the expected structure.

Step 2: Synthesis of 2,2 '- {disulfanediylbis [ethane-2,1-diyl (methylimino) -4,1-phenylene-ethen-2,1-diyl]} bis (1,3,3-trimethyl) chloride 3H-indolium [1] 4 g of 4 '- {disulfanediylbis [ethane-2,1-diyl (methylimino)]} dibenzaldehyde and 3.9 g of 1,3,3-trimethyl-2-methyleneindoline are mixed in 30 ml of methanol then 5 ml of 5N hydrochloric isopropanol are added dropwise After stirring for two hours at room temperature, the mixture is heated at 60 ° C. for 2 hours, 2 g of 1,3,3-trimethyl-2-methyleneindoline are added. and the stirring is maintained for 2 hours at 60 ° C. Once cooled, the mixture is poured into 500 ml of ethyl acetate, filtered and dried, and the product is then purified by liquid-water / butanol / tertiary liquid chromatography. Butylmethyl ether 2.67 g of black powder are collected after concentration and drying under vacuum The analyzes show that the product is 1 H NMR (CD3OD, multiplicity, proton number): 1.8ppm, s, 1 2H, 3.05ppm, t, 4H, 3.22ppm, s, 6H, 3.92ppm, t, 4H; 3.99 ppm, s, 6H; 6.97 ppm, d, 4H; 7.25 ppm, d, 2H; 7.54 ppm, 2m, 4H; 7.65ppm, 2m, 4H; 7.96 ppm, d, 4H; 8.3ppm, d, 2H FIA / MS: The expected dication [C44H52N4S2] 2+ is mainly detected at m / z, ESP + = 350.6 Example 2: Synthesis of 5-chloro-2- (2- {2 - [( 15- {2 - [- 2- (5-chloro-1,3,3-trimethyl-3H-indolium-2-yl) vinyl] phenyl} -4,4,11,11-tetramethyl-7,8-dithia 15-aza-4,11-diazoniahexadec-1-yl) (methyl) amino] phenyl} vinyl) -1,3,3-trimethyl-3H-indolium [2]

N-S-N-CI 4 Br CI [2] Synthesis scheme: 2 BrS-SBr / N

Method 1: Synthesis of 2 - [[3- (Dimethylamino) propyl] (methyl) amino] benzaldehyde 1.75 mL of N, N, N, N, N N'-trimethyl-1,3-propanediamine, 1 mL of 2-fluorobenzaldehyde and 1.45 g of potassium carbonate are stirred at 130 ° C. for 16 hours in 10 mL of dimethylsulfoxide. After cooling to 75 ° C., 15 mL of water are added, the mixture is kept for 3 h at 40 ° C. and then extracted with 3 times 25 ml of ethyl acetate. The ethyl acetate phases are combined, washed with three times 25 ml of water and then 25 ml of saturated sodium chloride solution, dried over magnesium sulfate and concentrated in vacuo. 2 g of red brown oil are collected. The analyzes show that the product conforms to the expected structure.

Step 2: Synthesis of N, N '- (disulfanediyldiethane-2,1-diyl) bis (3 - [(2-formylphenyl) (methyl) amino] -N, N-dimethylpropan-1-aminium dibromide 1.4 g 2,2'-Disulfanediylbis (1-bromoethane) and 2.64 g of 2 - [[3- (dimethylamino) propyl] - (methyl) amino] benzaldehyde are heated at 80 ° C for 2.5 h. After distilling acetonitrile under vacuum, the mixture is diluted in 5 mL of methanol and mixed with 150 mL of ethyl acetate. The solid obtained is diluted by dispersion in 15 mL of methanol and then mixed in 150 mL of ethyl acetate. The mother liquors are combined, concentrated under vacuum, 70 ml of ethyl acetate are added to the residue and the mixture is refluxed. Methanol is added until complete dissolution on heating and the mixture is cooled. The filtered precipitate is joined to the first solid; 2.28 g of yellow solid are collected. The analyzes show that the product conforms to the expected structure.

Step 3: Synthesis of 5-chloro-2--2- {2 - [(15- {2- [2- (5-chloro-1,3,3-trimethyl-3H-indolium-2-yl) tetrachloride) vinyl] phenyl) -4,4,11,11-tetramethyl-7,8-dithia-15-aza-4,11-diazoniahexadec-1-yl) (methyl) amino] phenyl} vinyl) -1,3,3 -trimethyl-3H-indolium [2]

1.77 g of N, N '- (disulphanediyldiethane-2,1-diyl) bis (3 - [(2-formylphenyl) - (methyl) amino] -N, N-dimethylpropan-1-aminium dibromide and 2 g of 5-chloro-1,2,3,3-tetramethyl-3H-indolium are mixed for 18 h at room temperature in 150 mL of methanol. 443 mg of 5-chloro-1,2,3,3-tetramethyl-3H-indolium are added and stirring is maintained for 6 hours. The product is purified in several times by sephadex column chromatography and the collected pure fractions are deposited on an ion exchange resin (Dowex chloride) and eluted with water. After lyophilization, 1.6 g of dark red solid are collected. The analyzes show that the product conforms to the expected structure.

EXAMPLE OF COLORING Coloring Process - Compounds [1] to [2] Preparation of Composition A Compounds [1] or [2] 5x10-4 mol% Benzyl Alcohol 4 g Polyethylene Glycol 60E 6 g Hydroxyethylcellulose 0.7 g Alkylpolyglucoside in solution aqueous solution at 4.5 g 65% MA Demineralized water qs 100 g Preparation of a composition B Thioglycolic acid 1M Sodium hydroxide Demineralized water qsp pH 8.5 qsp 100g At the time of use, the compositions A (9 ml) and B (1 mL), then apply the formulas on locks of natural white hair with 90% of white (BN), permanent white (BP) or chestnut of pitch 4 (HT4). The exposure time is 20 minutes at room temperature (RT). After rinsing with running water a fixative (Dulcia Vital II) diluted by 10 with water is applied for 5 minutes at RT. After rinsing with running water and shampooing, the locks are air dried. In shampoos, there is no visible bleeding, shampoo foam and rinsing water are not colored. (I) Optical brightening dyeing: Hair coloring thus treated was dyed with dyes 1, 2 or 3 Dark wicks HT4 became visually brighter than untreated control wicks. Coloring of the white locks: The natural white BN and white permed BP hair are colored fuchsia. ii) Remanence with respect to successive shampooinqs: The treated locks are divided in two, one half is subjected to 5 successive shampoos in a cycle which comprises wetting the locks with water, washing with a conventional shampoo, rinsing with water followed by drying.

In shampoos, there is no visible bleeding, the foam of the shampoos and the rinsing water are not colored. The observed color remains visible on the HT4, BN and BP hair thus treated. 15

Claims (22)

1. Fluorescent dye of formulas (I), (II) or (III): (R1) An / R4 \ 2 / Y SI (R1) p An, R5 + An / L 6 N, N + 1 \ YsS 4 4 its organic or inorganic acid salts, optical isomers, geometric isomers, and solvates such as hydrates; formulas (I), (II) and (III) in which: p or p 'represent an integer inclusive between 0 and 4; R 'represents a halogen atom, a (C 1 -C 6) alkyl, (C 1 -C 6) alkoxy, (C 1 -C 6) alkylthio, (di) (C 1 -C 6) (alkyl) amino group; (C 1 -C 6) poly-haloalkyl, hydroxy, (C 1 -C 6) polyhydroxyalkyl, polyhydroxy (C 1 -C 6) alkoxy, cyano, RGC (G ') -, RC (G') - G-, R'S ( 0) 2-N (R) -, RR'NS (O) 2- with G or G ', identical or different, representing an oxygen atom, sulfur or a group NR', and R and R ', identical or different, representing a hydrogen atom or a (C 1 -C 6) alkyl group; - R2 and R3, identical or different, represent a group (C, -C6) alkyl particularly R2 and R3 are identical and represent a methyl group; - R4 and R5, represent an alkyl group, or aryl (C1-C6) alkyl, it being understood that R4 represents a bond when the radical - LûSû of the disulfide dye of formula (I) is connected to R4; B represents an optionally substituted aryl or optionally substituted heteroaryl group; L represents an optionally substituted C1-C20 bivalent hydrocarbon chain, optionally interrupted and / or optionally terminated at either of its ends i) by one or more divalent groups or combinations thereof chosen from: ) -; -N + (Ra) (Rb) -, An'-; -O-, -S-, -C (O) -, -S (O) 2- with Ra and Rb, identical or different, selected from hydrogen, (C 1 -C 6) alkyl, hydroxy (C, -C6) alkyl, (di) (C 1 -C 6) (alkyl) amino (C 1 -C 6) alkyl and An-representing an anionic counterion or ii) cationic heterocycle or cationic heteroaryl Het +, An-, with An'-as defined above and Het + representing a heterocycle comprising 5 to 10 members, saturated or not, or a heteroaryl comprising 5 to 10 members; Y represents: i) a hydrogen atom; ii) an alkali metal; iii) an alkaline earth metal; iv) an ammonium group: N + RaRRRYRs, or a phosphonium group: P + RaRRRYRs, with Ra, RR, R7 and R8, identical or different, representing a hydrogen atom or a (C 1 -C 4) alkyl or ) a protecting group of thiol function; - An- represents an anionic counterion; it being understood that: when p is between 2 and 4, the groups R 'are identical or different, when p' is between 2 and 3, the groups R 'are identical or different, when the dye of formula (II) contains a group Y representing a hydrogen atom or an alkali metal, then the radical L can not represent a bivalent hydrocarbon chain at 02-04, the chain Li-S- is linked to the indolinium-derived chromophore of formula (I) particularly by A, R4 or B, formulas (I), (II) or (III) may contain other anionic counterions to achieve electroneutrality. 2. Fluorescent dye of formula (II) or (III) according to the preceding claim wherein Y represents a hydrogen atom, or an alkali metal. 3. Fluorescent dye of formula (II) or (III) according to claim 1 wherein Y represents a protective group. 4. Fluorescent dye of formula (II) or (III) according to the preceding claim wherein Y represents a protective group selected from the following radicals: (C 1 -C 4) alkylcarbonyl; (C 1 -C 4) alkylthiocarbonyl; (C 1 -C 4) alkoxycarbonyl; (C 1 -C 4) alkoxythiocarbonyl; (C 1 -C 4) alkylthiothiocarbonyl; ^ (di) (C1-C4) (alkyl) aminocarbonyl; ^ (di) (C1-C4) (alkyl) aminothiocarbonyl; arylcarbonyl; aryloxycarbonyl; Aryl (C 1 -C 4) alkoxycarbonyl; • (di) (C1-C4) (alkyl) aminocarbonyl; (C 1 -C 4) (alkyl) arylaminocarbonyl; carboxy; SO3; M` with M + representing an alkali metal or else An- of the formula (II) or (III) and M + are absent; optionally substituted aryl; Optionally substituted heteroaryl; Optionally substituted heterocycloalkyl, optionally cationic, the following group: R'd% R'9 NIL R, h N '(CR'eR'f) "r R'd An' in which R '°, R'd, R'e, R'f, R'9 and R'h, identical or different, represent a hydrogen atom or a (C1-C4) alkyl group, or else two R'9 groups with R'h, and / or R'e with R'f form an oxo or thioxo group, or else R'9 with R'e together form a cycloalkyl, and v represents an integer inclusive of between 1 and 3, and An 'represents a counterion ^ isothiouronium ; -C (NR "R'd) = N + RieR'f; An '"with R' °, R'd, R'e and R'f, identical or different, represent a hydrogen atom or a group (C, -C4) alkyl and Anest as defined above; isothiourea; -C (NR '° R'd) = NRie, with R'd, R'd and R'e are as defined above; • (di) aryl (C, -C4) optionally substituted alkyl; • (di) optionally substituted heteroaryl (C 1 -C 4) alkyl; CR'R 2 R 3 with R ', R 2 and R 3, which may be identical or different, representing a halogen atom or a group chosen from: - (C 1 -C 4) alkyl; , -C4) alkoxy; - optionally substituted aryl; - optionally substituted heteroaryl; P (Z ') R''R'2R'3 with R'1, and R'2, which may be identical or different, represent a hydroxy group, (C1-C4) alkoxy or alkyl, R '3 represents a hydroxy or (C 1 -C 4) alkoxy group, and Z' represents a sterically hindered cyclic oxygen or ring atom, and • optionally substituted alkoxyalkyl. 5. Fluorescent dye of formula (I) according to any one of the preceding claims wherein Y represents an alkali metal or a protective group selected from - (C1-C4) alkylcarbonyl; -arylcarbonyl; - (C1-C4) alkoxycarbonyl; aryloxycarbonyl; -aryl (C1-C4) alkoxycarbonyl; - (di) (C1-C4) (alkyl) aminocarbonyl; - (C1-C4) (alkyl) arylaminocarbonyl; optionally substituted aryl; 5- or 6-membered cationic monocyclic heteroaryl optionally substituted by one or more, identical or different, (C 1 -C 4) alkyl groups; 8 to 11-membered cationic bicyclic heteroaryl optionally substituted by one or more, identical or different, (C 1 -C 4) alkyl groups; cationic heterocycle of the following formula: Me 1 N + N-Me An '"-; - isothiouronium; -C (NH 2) = N + H 2; An'" -; with An "" representing an anionic counterion; Isothiourea; -C (NH2) = NH; and - SO3; M + with M + representing an alkali metal or else An- of the formula (II) or (III) and M + are absent. 6. Fluorescent disulfide dye of formula (I) according to claim 1, chosen from those of formula (Ia), (Ib) and Oc): (la) 6 1 (R) p / Si / Ta (CH2) m (CH2) ) to Ta 2 R N (CH) (CH) N + 2.2, R 3 A (Ib) A-1 2 nn BB 3 R 2 / Si R 4 T (CH) (CH) T a2m27 / a Where (CH 2) n (CH2) 7X 6 +1 N R4 An (R1) p, Oc) (R1) p7 An ~~ R4 formulas (la), (Ib) and Oc) in which: - p, p ', R' to R4 , B and An- are as defined in claim 1; - n and m, identical or different, represent an integer inclusive between 1 and 6 with the sum of n + m which is inclusive between 2 and 4; X represents a radical chosen from: -G-, -G'-C (G) - and -C (G) -G'-, with G and G ', which may be identical or different, representing an oxygen atom, sulfur, or NR, with R representing a hydrogen atom or a (C1-C6) alkyl group, advantageously X represents a group -NR-, -NR-CO-, -C (O) -NR-, -S (O) 2-, -S (O) 2-NR-; or -NR-S (O) 2-, or -NR-; -Ta represents a covalent bond 6, a group ùN (R'a) -; -N + (R'a) (R'b) -, An-; -C (O) -N (R'a) - or -N (R'a) -C (O) -, or a divalent cationic heteroaryl comprising from 5 to 7 members, such as imidazolium, with R'a, R b, identical or different, representing a hydrogen atom, a (C1-C4) alkyl radical, An- representing an anionic counterion. 7. Fluorescent dye of formula (I), (Ia), (Ib) and Oc) and (II) according to any one of the preceding claims, chosen from the following dyes: SiSi, Ta (C 2) m (CH 2) ## STR5 ## wherein m is embedded in the formula ## STR2 ## ## STR6 ## ## STR2 ## ## STR2 ## ## STR8 ## ## STR5 ## wherein Y is the same or different, representing an anionic counterion. 8. dye composition comprising in a suitable cosmetic medium, at least one fluorescent dye of formula (I), (II) or (III) as defined in any one of claims 1 to 7. 9. Dyeing composition according to the preceding claim comprising in a suitable cosmetic medium: at least one fluorescent dye of formula (I), (II) or (III) as defined in any one of claims 1 to 7; o and at least one reducing agent. 10. Dyeing composition according to the preceding claim wherein the reducing agent is chosen from: cysteine, homocysteine, thiolactic acid, the salts of these thiols, phosphines, bisulfite, sulfites, thioglycolic acid, and its esters, borohydrides and their derivatives, sodium, lithium, potassium, calcium, quaternary ammonium salts and catecholborane. 11. Composition according to any one of claims 8 to 10, wherein the fluorescent dye of formula (I), (II) or (III) is present in an amount of between 0.001 and 50% by weight relative to the total weight of the composition. 12. A method for dyeing keratinous fibers, wherein a suitable dye composition comprising at least one fluorescent dye of formula (I), (II) or (III) according to any one of claims 8 to 11 is applied to the materials. 13. The method of dyeing according to the preceding claim wherein when the fluorescent dye of formula (II) or (III) comprises a protective Y group, the application is preceded by a deprotection step. 14. A method of dyeing keratin materials according to any one of claims 12 or 13, characterized in that the keratin materials are dark keratinous fibers having a pitch of less than or equal to 6. 15. A process according to any one of claims 12 to 14, wherein the reducing agent is applied before or after the application of the fluorescent dye of formula (I), (II) or (III) as defined in the claims 1 to 7. The process of any one of claims 12 to 15, wherein the composition comprises an oxidizing agent. 35 17. A method according to any one of claims 12 to 16 comprising a further step of applying to the keratin fibers an oxidizing agent. 18. Multi-compartment device wherein a first compartment contains a dye composition comprising a fluorescent dye of formula (I), (II) or (III) as defined in claims 1 to 7 and a second compartment contains a reducing agent. 19. Device according to the preceding claim comprising a third compartment which contains an oxidizing agent. 20. Use of fluorescent dyes of formula (I), (II) or (III) as defined in claims 1 to 7 for dyeing dark human keratin fibers. 21. Use according to the preceding claim for lightening dark keratin fibers. 15 22. Use according to claims 20 or 21 characterized in that the keratinous fibers have a pitch of less than 6.5