WO2000038632A1

WO2000038632A1 - Method for dying keratin fibers using 2-oxocarboxylic acid derivatives in conjunction with nucleophiles

Info

Publication number: WO2000038632A1
Application number: PCT/EP1999/009907
Authority: WO
Inventors: Hinrich Möller; Horst Höffkes
Original assignee: Henkel Kommanditgesellschaft Auf Aktien
Priority date: 1998-12-23
Filing date: 1999-12-14
Publication date: 2000-07-06
Also published as: DE19859722A1; AU1658700A

Abstract

The invention relates to a method for dying keratin fibers, especially human hair, using dying agents which are applied to the fiber. The dying agents comprise; A) 2-oxocarboxylic acid derivatives with formula (I), wherein R1 represents a hydrogen atom, a C¿1?-C4-alkyl group, a carboxyl radical, a carboxylate radical, an aryl group, benzyl group or heteroaryl group, which can be substituted by one or more C1-C4-alkyl group(s), C1-C4-alkoxy group(s), C1-C4-hydroxyalkoxy group(s), hydroxy group(s), carboxy group(s), sulfo group(s) or nitro group(s); X represents O?-¿, OH, a C¿1?-C4-alkoxy group or an NR?2R3¿-group, in which R?2 and R3¿ are the same or different and they represent hydrogen, C¿1?-C4-alkyl or hydroxy-C2-C4-alkyl, whereby, if X represents NR?2R3¿, radicals R?2 and R3¿ can, together with the nitrogen atom, also form a heterocyclic ring. A) is used in conjunction with; B) at least one compound with a primary or secondary amino group or hydroxy group selected from primary or secondary aliphatic or aromatic amines, nitrogenous heterocyclic compounds, oligopeptides constructed from 2 to 9 amino acids, and aromatic hydroxy compounds, and/or from at least one CH-active compound.

Description

"Process for dyeing keratin fibers using 2-oxocarboxylic acid derivatives in combination with nucleophiles"

The invention relates to a process for dyeing fibers containing keratin, in particular human hair, in which 2-oxocarboxylic acid derivatives are used in combination with nucleophiles or the reaction product thereof as a coloring component.

For dyeing keratin fibers, e.g. B. hair, wool or fur, generally either direct dyes or oxidation dyes, which are formed by oxidative coupling of one or more developer components with one another or with one or more coupler components, are used. Coupler and developer components are also referred to as oxidation dye precursors.

Primary aromatic amines with a further free or substituted hydroxy or amino group in the para or ortho position, diaminopyridine derivatives, heterocyclic hydrazones, 4-aminopyrazolone derivatives and 2,4,5,6-tetraaminopyrimidine and derivatives thereof are usually used as developer components.

Specific representatives are, for example, p-phenylenediamine, p-toluenediamine, 2,4,5,6-tetraaminopyrimidine, p-aminophenol, N, N-bis- (2-hydroxyethyl) -p-pheny- lendiamine, 2- (2,5-diaminophenyl) ethanol, 2- (2,5-diaminophenoxy) ethanol, 1-phenyl-3-carboxyamido-4-amino-pyrazolone-5, 4-amino-3-methylphenol, 2-amino-methyl-4-aminophenol, 2-hydroxymethyl-4-aminophenol, 2-hydroxy-4,5,6-triaminopyrimidine, 2,4-dihydroxy-5,6-diaminopyrimidine and 2,5,6- Triamino-4-hydroxypyrimidine.

M-Phenylenediamine derivatives, naphthols, resorcinol and resorcinol derivatives, pyrazolones and m-aminophenols are generally used as coupler components. Suitable coupling substances are, in particular, α-naphthol, 1, 5-, 2,7- and 1, 7-dihydroxynaphthalene, 5-amino-2-methylphenol, m-aminophenol, resorcinol, resorcinol monomethyl ether, m-phenylenediamine, 2,4-diaminophenoxyethanol , 1-phenyl-3-methyl-pyrazolon-5, 2,4-dichloro-3-aminophenol, 1, 3-bis (2,4-diaminophenoxy) propane, 2-chlororesorcinol, 4-chlororesorcinol, 2nd -Chlor-6-methyl-3-aminophenol, 2-methylresorcinol and 5-methylresorcinol.

With regard to other conventional dye components, reference is expressly made to the "Dermatology" series, edited by Ch. Culnan, H. Maibach, Marcel Dekker Inc., New York, Basel, 1986, Vol. 7, Ch. Zviak, The Science of Hair Care, Cape. 7, pages 248 - 250 (direct dyes), and chap. 8, pages 264 - 267 (oxidation dyes), as well as the "European Inventory of Cosmetic Raw Materials", 1996, published by the European Commission, available in disk form from the Federal Association of German Industrial and Commercial Enterprises for Medicines, Health Care Products and Personal Care Products, Mannheim .

With oxidation dyes intensive dyeings can be achieved with good fastness properties, but the development of the color is usually done under the influence of oxidizing agents such. B. H ₂ 0 ₂ , which in some cases can result in damage to the fiber. Furthermore, some oxidation dye precursors or certain mixtures of oxidation dye precursors can sometimes be found in people with sensitive skin act sensitizing. Direct dyes are applied under gentler conditions, but their disadvantage is that the dyeings often have inadequate fastness properties.

The object of the present invention is to provide colorants for keratin fibers, in particular human hair, which are qualitatively at least equivalent to the usual oxidation hair colorants in terms of color depth, gray coverage and fastness properties, but without necessarily relying on oxidizing agents such as e.g. B. H ₂ O _{2 to be} instructed. In addition, the colorants may have no or only a very low sensitization potential.

Surprisingly, it has now been found that the 2-oxocarboxylic acid derivatives shown in formula I in combination with nucleophiles or their reaction products, as defined below, are outstandingly suitable for dyeing keratin-containing fibers. In particular with customary oxidation dye precursors, they result in colorations with excellent brilliance and depth of color and lead to a wide range of color shades. The use of oxidizing agents is not necessary, but should not be excluded in principle.

The present invention accordingly relates to a process for dyeing fibers containing keratin, in particular human hair, in which (A) 2-oxocarboxylic acid derivatives having the formula (I)

wherein R represents a hydrogen atom, a C _r C ₄ alkyl group, a carboxyl radical, a carboxylate radical, an aryl, benzyl or heteroaryl group, which can be substituted by one or more C _r C ₄ alkyl, C _r C ₄ alkoxy, C _r C ₄ hydroxyalkoxy, hydroxy, carboxy, sulfo or nitro group (s), X for O ^" , OH, a C _r C ₄ alkoxy or an NR ² R ³ group in which R ² and R ^{3 are the} same or different and hydrogen, C _r C ₄ alkyl or hydroxy-C ₂ -C ₄ -alkyl, where, when X is NR ² R ³ , the radicals R ² and R ^{3 can} also form a heterocyclic ring together with the nitrogen atom, in combination with

(B) at least one compound having a primary or secondary amino group or hydroxy group, selected from primary or secondary aliphatic or aromatic amines, nitrogen-containing heterocyclic compounds, from 2 to 9 amino acids and oligopeptides and aromatic hydroxy compounds, and / or at least one CH-active compound, or the reaction product from components A and B are applied to the fiber as a coloring component.

Another object of the present invention is an agent for dyeing keratin fibers, in particular human hair, which contains as a coloring component

(A) one or more 2-oxocarboxylic acid derivatives with the formula I and

(B) at least one compound having a primary or secondary amino group or hydroxy group, selected from primary or secondary aliphatic or aromatic amines, nitrogen-containing heterocyclic compounds, from 2 to 9 amino acids and oligopeptides and aromatic hydroxy compounds, and / or at least one CH-active compound, where the reaction product from components A and B may also be present. Keratin-containing fibers are wool, furs, feathers and in particular human hair. In principle, however, the colorants according to the invention can also be used for dyeing other natural fibers, such as, for. As cotton, jute, sisal, linen or silk, modified natural fibers, such as. B. regenerated cellulose, nitro, alkyl or hydroxyalkyl or acetyl cellulose and synthetic fibers such as. B. polyamide, polyacrylonitrile, -, polyurethane and polyester fibers can be used.

The 2-oxocarboxylic acid derivatives of the formula I used according to the invention are preferably selected from the group consisting of pyruvic acid, glyoxylic acid, mesoxalic acid, phenylglyoxylic acid, 2-

Hydroxyphenylglyoxylic acid, phenylpyruvic acid, 4-

Nitrophenylglyoxylic acid, 4-methoxyphenylglyoxylic acid, 3-indolylglyoxylic acid and their sodium, potassium and calcium salts and C _r C ₄ -alkyl esters, 6-methoxy-3-indolylglyoxylic acid and their amide, 2-furylglyoxylic acid and their amide thereof, 3-indolylglyoxylic acid amide, 3 -Indolylglyoxylsäuredimethylamid and their mixtures.

These substances are known from the literature or are commercially available.

The above-mentioned 2-oxocarboxylic acid derivatives with the formula I are preferably used in the process according to the invention in an amount of 0.03 to 65 mmol, in particular from 1 to 40 mmol, based on 100 g of the entire colorant.

If the 2-oxocarboxylic acid derivatives with the formula I are used as the only colorant in the process according to the invention, colorations in the brown range are obtained. Colorings with further increased brilliance and improved fastness properties (light fastness, wash fastness, rub fastness), especially in the yellow, orange, brown and black range, are achieved if the Compounds with the formula I are used together with the compounds referred to as component B. On the one hand, these are compounds which, on their own, only weakly dye keratin-containing fibers and only give brilliant colors together with the 2-oxocarboxylic acid derivatives of the formula I. On the other hand, there are also compounds that are already used as oxidation dye precursors.

The compounds of component B can be used in an amount of 0.03 to 65, in particular 1 to 40, mmol, in each case based on 100 g of the total colorant.

Several different 2-oxocarboxylic acids or their derivatives of the formula I can also be used together in the process according to the invention; Likewise, several different compounds of component B can also be used together. This embodiment also includes the use of those substances which are reaction products of compounds of the formula I with the compounds of component B mentioned.

Suitable compounds with primary or secondary amino group as component B are e.g. B. primary aromatic amines such as N, N-dimethyl, N, N-diethyl, N- (2-hydroxyethyl) -N-ethyl, N, N-bis (2-hydroxyethyl) -, N- (2nd -Methoxyethyl-), 2,3-, 2,4-, 2,5-dichloro-p-phenylenediamine, 2-chloro-p-phenylenediamine, 2,5-dihydroxy-4-morpholinoaniline dihydrobromide, 2-, 3- , 4-aminophenol, 2-aminomethyl-4-aminophenol, 2-hydroxymethyl-4-aminophenol, o-, p-phenylenediamine, o-toluenediamine, 2,5-diaminotoluene, -phenol, -phenethol, 4-amino- 3-methylphenol, 2- (2,5-diaminophenyl) ethanol, 2,4-diaminophenoxyethanol, 2- (2,5-diaminophenoxy) ethanol, 4-methylamino, 3-amino-4- (2 ' -hydroxyethyloxy) -, 3,4-methylenediamino-, 3,4-methylenedioxyaniline, 3-amino-2,4-dichloro-, 4-methylamino-, 2-methyl-5-amino-, 3-methyl-4 -amino-, 2-methyl-5- (2-hydroxyethylamino) -, 6-methyl-3-amino-2-chloro, 2-methyl-5-amino-4-chloro, 3,4-methylenedioxy -, 5- (2-

Hydroxyethylamino) -4-methoxy-2-methyl-, 4-amino-2-hydroxymethylphenol, 1, 3- Diamino-2,4-dimethoxybenzene, 2-, 3-, 4-aminobenzoic acid, -phenylacetic acid, 2,3-, 2,4-, 2,5-, 3,4-, 3,5-diaminobenzoic acid, 4-, 5-aminosalicylic acid, 3-amino-4-hydroxy-, 4-amino-3-hydroxy-benzoic acid, 2-, 3-, 4-aminobenzenesulfonic acid, 3-amino-4-hydroxybenzenesulfonic acid, 4-amino-3-hydroxynaphthalene-1 -sulfonic acid, 6-amino-7-hydroxynaphthalene-2-sulfonic acid, 7-amino-4-hydroxynaphthalene-2-sulfonic acid, 4-amino-5-hydroxynaphthalene-2,7-disulfonic acid, 3-amino-2-naph - thoic acid, 3-aminophthalic acid, 5-aminoisophthalic acid, 1, 3,5-, 1, 2,4-triamino-benzene, 1, 2,4,5-tetraaminobenzene, 2,4,5-triaminophenol, 2,4, 6-triaminoresorcinol, 4,5-diamino-catechol, 4,6-diaminopyrogallol, 3,5-diamino-4-hydroxybenzate catechol, aromatic nitriles, anilines, in particular anilines containing nitro groups, such as 4-nitroaniline, 4-nitro-1, 3-phenylenediamine, 2-nitro-4-amino-1- (2-hydroxyethylamino) benzene, 2-nitro-1-amino-4- [bis- (2-hydroxyethyl) amino] benzene, 4-amino- 2-nitrodiphenylamine-2'-carboxylic acid, 2 -Amino-6-chloro-4-nitrophenol, 1 -Amino-5-chloro-4- (2-hydroyethylamino) -2-nitrobenzene, aromatic anilines or phenols with a further aromatic radical, as shown in formula II

in which R ^{4 represents} a hydroxy or an amino group which may be substituted by C 1-4 alkyl, C 1-4 hydroxyalkyl, C 1-4 alkoxy or C 1-4 alkoxy-C 1-4 alkyl groups,

R ⁵ , R ⁶ , R ⁷ , R ⁸ and R ^{9 represent} hydrogen, a hydroxy or an amino group,

C ₁ . ₄ -Alkyl-, C ^ -hydroxyalkyl, C ^ -alkoxy-, C _M -aminoalkyl- or C ^ -alkoxy-C ^ - alkyl groups can be substituted, and

Y for a direct bond, a saturated or unsaturated carbon chain with 1 to 4 carbon atoms, optionally substituted by hydroxyl groups, a Car- bonyl, sulfonyl or imino group, an oxygen or sulfur atom, or a group with the formula III

Z- (CH ₂ -Q-CH ₂ -Z ') ₀ (III)

in which Q denotes a direct bond, a CH ₂ or CHOH group,

Z and Z 'independently of one another for an oxygen atom, an NR ¹⁰ group, in which R ^{10 is} hydrogen, a C 1-4 alkyl or a hydroxy-C 1-4 alkyl group, the group 0- (CH ₂ ) _p -NH or NH- (CH ₂ ) _p '-O, where p and p' are 2 or 3 and o is a number from 1 to 4, such as 4,4'-diaminostilbene and its hydrochloride, 4,4'- Diamino-stilbene-2,2'-disulfonic acid mono- or di-Na salt, 4-amino-4'-dimethylaminostilbene, 4-amino-4'-dimethylaminostilbene dihydrochloride, 4,4'-diaminodiphenylmethane, -sulfide, -sulfoxide, -amine, 4,4'-diaminodiphenylamine-2-sulfonic acid, 4,4'-diaminobenzophenone, -diphenyl ether, 3,3 ', 4,4'-tetraaminodiphenyl, 3,3', 4 , 4'-tetraamino-benzophenone, 1,3-bis (2,4-diaminophenoxy) propane, 1,8-bis (2,5-diaminophenoxy) -3,6-dioxaoctane, 1,3-bis- (4-aminophenylamino) propane, -2-propanol, 1,3-bis- [N- (4-aminophenyl) -2-hydroxyethylamino] -2-propanol, N, N-bis- [2- (4-aminophenoxy) -ethyl] -methylamine, N-phenyl-1,4-phenylenediamine.

The abovementioned compounds can be used both in free form and in the form of their physiologically tolerable salts, in particular as salts of inorganic acids, such as hydrochloric or sulfuric acid.

Suitable nitrogen-containing heterocyclic compounds are e.g. B. 2-, 3-, 4- amino-, 2-amino-3-hydroxy-, 2,6-diamino-, 2,5-diamino-, 2,3-diamino-, 2-dimethylamino-5 -amino-, 2-methylamino-3-amino-6-methoxy-, 2,3-diamino-6-methoxy-, 2,6-dimethoxy-3,5-diamino-, 2,4,5-triamino-, 2,6-dihydroxy-3,4-dimethylpyridine, 2,4-dihydroxy-5,6-diamino-, 4,5,6-triamino-, 4-hydroxy-2,5,6-triamino-, 2-hydroxy -4,5,6-triamino-, 2,4,5,6-tetraamino-, 2-methylamino-4,5,6- triamino-, 2,4-, 4,5-diamino-, 2-amino-4-methoxy-6-methyl-pyrimidine, 3,5-diaminopyrazole, -1, 2,4-triazole, 3-amino-, 3rd -Amino-5-hydroxypyrazole, 2-, 3-, 8-aminoquinoline, 4-aminoquinidine, 2-, 6-aminonicotinic acid, 5-aminoisoquinoline, 5-, 6-aminoindazole, 5-, 7-aminobenzimidazole, -benzothiazole, 2 , 5-dihydroxy-4-morpholinoaniline and indole and indoline derivatives, such as 4-, 5-, 6-, 7-aminoindole, 5,6-dihydroxyindole, 5,6-dihydroxyindoline and 4-hydroxyindoline. The aforementioned compounds can be used both in free form and in the form of their physiologically tolerable salts, e.g. B. as salts of inorganic acids such as hydrochloric or sulfuric acid.

Suitable aromatic hydroxy compounds are e.g. B. 2-, 4-, 5-methylresorcinol, 2,5-dimethylresorcinol, resorcinol, 3-methoxyphenol, pyrocatechol, hydroquinone, pyrogallol, phloroglucin, hydroxyhydroquinone, 2-, 3-, 4-methoxy, 3-dimethylamino, 2- (2-hydroxyethyl) -, 3,4-methylenedioxyphenol, 2,4-, 3,4-dihydroxybenzoic acid, -phenylacetic acid, gallic acid, 2,4,6-trihydroxybenzoic acid, -acetophenone, 2-, 4 -Chlorresorcin, 1-naphthol, 1, 5-, 1, 6-, 1, 7-, 2,3-, 2,6-, 2,7-dihydroxynaphthalene, 2-naphthol-3,6-disulfonic acid Na- Salt, 6-dimethylamino-4-hydroxy-2-naphthalenesulfonic acid, 3,6-dihydroxy-2,7-naphthalenesulfonic acid.

The oligopeptides can be naturally occurring or synthetic oligopeptides, but also the oligopeptides contained in polypeptide or protein hydrolyzates, provided they have sufficient water solubility for use in the colorants according to the invention. As examples are e.g. As glutathione or the oligopeptides contained in the hydrolyzates of collagen, keratin, casein, elastin, soy protein, wheat gluten or almond protein. Use together with compounds having a primary or secondary amino group or with aromatic hydroxy compounds is preferred.

Examples of CH-active compounds which may be mentioned are 1, 2,3,3-tetramethyl-3H-indolium iodide, 1, 2,3,3-tetramethyl-3H-indolium-p-toluenesulfonate, 1, 2,3,3-tetramethyl-3H-indolium methanesulfonate, Fischer's base (1,3,3-trimethyl-2-methyleneindoline) (as a salt of a strong acid), 2,3-dimethyl-benzothiazolium iodide, 2 , 3-dimethyl-benzothiazolium-p-toluenesulfonate, rhodanine, rhodanine-3-acetic acid, 1-ethyl-2-quinal dinium iodide, 1-methyl-2-quinal dinium iodide, barbituric acid, thiobarbituric acid, 1, 3-dimethylthiobarbituric acid, diethylthiobiouric acid 3-indoxy acetate, coumaranone and 1-methyl-3-phenyl-2-pyrazolinone.

The compounds of component B are particularly preferably selected from the group consisting of N- (2-hydroxyethyl) -N-ethyl-, 2-chloro-p-phenylene-diamine, N, N-bis (2-hydroxyethyl) -p- phenylenediamine, 4-aminophenol, p-phenylenediamine, 2- (2,5-diaminophenyl) ethanol, 2,5-diaminotoluene, 3,4-methylenedioxyaniline, 3-amino-2,4-dichloro-, 2 -Methyl-5-amino-, 3-methyl-4-amino-, 2-methyl-5- (2-hydroxyethylamino) -, 2-methyl-5-amino-4-chloro, 6-methyl-3-amino -2-chloro, 2-aminomethyl-4-amino, 2-hydroxymethyl-4-amino, 2-amino-4- (2-hydroxyethylamino) -, 3,4-methylenedioxyphenol, 3,4-diaminobenzoic acid , 2,5-diamino-, 2-dimethylamino-5-amino-, 3-amino-2-methylamino-6-methoxy-, 2,3-diamino-6-methoxy-, 3,5-diamino-2,6 -dimethoxy-, 2,6-dihydroxy-3,4-dimethylpyridine, 2-hydroxy-4,5,6-triamino-, 4-hydroxy-2,5,6-triamino-, 2-methylamino-4,5, 6-triamino-pyrimidine, 3,5-diaminopyrazole, 3-amino-5-hydroxypyrazole, 5,6-dihydroxyindole, 5,6-dihydroxyindoline, 1-naphthol, 1, 5-, 1, 6-, 1, 7-, 2,3-, 2,6-, 2,7-dihy droxynaphthalene and 2-naphthol-3,6-disulfonic acid, Na salt and their physiologically tolerable salts formed with preferably inorganic acids.

On the presence of oxidizing agents, e.g. B. H ₂ 0 ₂ , can be omitted. However, it can It may be desirable to add hydrogen peroxide or other oxidizing agents in the process according to the invention to achieve the shades that are lighter than the keratin-containing fiber to be colored. Oxidizing agents are usually used in an amount of 0.01 to 6 % By weight, based on the application solution. A preferred oxidizing agent for human hair is H ₂ O ₂ .

In a preferred embodiment, in addition to the compounds used according to the invention, customary direct dyes, e.g. B. from the group of nitrophenylenediamines, nitroaminophenols, azo dyes, anthraquinones or indophenols. Preferred direct dyes are those with the international names or trade names HC Yellow 2, HC Yellow 4, HC Yellow 5, HC Yellow 6, Basic Yellow 57, Disperse Orange 3, HC Red 3, HC Red BN, Basic Red 76, HC Blue 2, HC Blue 12, Disperse Blue 3, Basic Blue 99, HC Violet 1, Disperse Violet 1, Disperse Violet 4, Disperse Black 9, Basic Brown 16 and Basic Brown 17 known compounds as well as 4-amino-2-nitrodipheny-lamin- 2'-carboxylic acid, 6-nitro-1, 2,3,4-tetrahydroquinoxaline, hydroxyethyl-2-nitro-toluidine, picramic acid, 2-amino-6-chloro-4-nitrophenol, 4-ethylamino-3-nitrobenzoic acid and 2-chloro-6-ethylamino-1-hydroxy-4-nitrobenzene. The agents according to the invention in accordance with this embodiment preferably contain the substantive dyes in an amount of 0.01 to 20% by weight, based on the total colorant.

Furthermore, the preparations according to the invention can also contain naturally occurring dyes such as, for example, henna red, henna neutral, henna black, chamomile flowers, sandalwood, black tea, rotten bark, sage, blue wood, madder root, catechu, sedre and alkanna root.

It is not necessary that the oxidation dye precursors or the optional direct dyes each represent uniform compounds. Rather, in the present invention, due to the manufacturing process for the individual dyes, additional components can be used in minor amounts, provided that these are not Adversely affect the coloring result or for other reasons, e.g. B. toxicological, must be excluded.

The agent according to the invention produces intensive colorations even at physiologically tolerable temperatures of below 45 ° C. It is therefore particularly suitable for dyeing human hair. For use on human hair, the individual components are usually worked into a water-containing cosmetic carrier. Suitable water-containing cosmetic carriers are e.g. B. creams, emulsions, gels or surfactant-containing foaming solutions such. B. shampoos or other preparations that are suitable for use on the keratin fibers. If necessary, it is also possible to incorporate the components into anhydrous carriers.

Furthermore, all active ingredients, additives and auxiliaries known in such preparations can be used in the process according to the invention. In many cases at least one surfactant is included, with both anionic and zwitterionic, ampholytic, nonionic and cationic surfactants being suitable in principle. In many cases, however, it has proven advantageous to select the surfactants from anionic, zwitterionic or nonionic surfactants.

Suitable anionic surfactants in preparations according to the invention are all anionic surface-active substances suitable for use on the human body. These are characterized by a water-solubilizing, anionic group such as. B. a carboxylate, sulfate, sulfonate or phosphate group and a lipophilic alkyl group with about 10 to 22 carbon atoms. In addition, the molecule can contain glycol or polyglycol ether groups, ester, ether and amide groups and hydroxyl groups. Examples of suitable anionic surfactants are, in each case in the form of the sodium, potassium and ammonium as well as the mono-, di- and trialkanolammonium salts with 2 or 3 carbon atoms in the alkanol group, linear fatty acids with 10 to 22 carbon atoms (soaps),

Ether carboxylic acids of the formula R-0- (CH ₂ -CH ₂ 0) _x -CH ₂ -COOH, in which R is a linear alkyl group with 10 to 22 C atoms and x = 0 or 1 to 16, acyl sarcosides with 10 to 18 C atoms in the acyl group, acyl taurides with 10 to 18 C atoms in the acyl group, acyl isethionates with 10 to 18 C atoms in the acyl group, sulfosuccinic acid and dialkyl esters with 8 to 18 C atoms in the alkyl group and sulfosuccinic acid mono-alkyl polyoxyethyl ester with 8 to 18 carbon atoms in the alkyl group and 1 to 6 oxyethyl groups, linear alkanesulfonates with 12 to 18 carbon atoms, linear alpha-olefin sulfonates with 12 to 18 carbon atoms, methyl alpha-sulfofatty acid esters of fatty acids with 12 to 18 carbon atoms , Alkyl sulfates and aikylpolyglycol ether sulfates of the formula R-0 (CH ₂ -CH ₂ 0) _x - S0 ₃ H, in which R is a preferably linear alkyl group with 10 to 18 carbon atoms and x = 0 or 1 to 12,

Mixtures of surface-active hydroxysulfonates according to DE-A-37 25 030, sulfated hydroxyalkyl polyethylene and / or hydroxyalkylene propylene glycol ethers according to DE-A-37 23 354,

Sulfonates of unsaturated fatty acids with 12 to 24 carbon atoms and 1 to 6 double bonds according to DE-A-39 26 344,

Esters of tartaric acid and citric acid with alcohols, the addition products of about 2 to 15 molecules of ethylene oxide and / or propylene oxide to fatty alcohols with 8 to 22 carbon atoms.

Preferred anionic surfactants are alkyl sulfates, alkyl polyglycol ether sulfates and ether carboxylic acids with 10 to 18 carbon atoms in the alkyl group and up to 12 glycol ether groups in the molecule, and in particular salts of saturated and in particular unsaturated C ₈ -C ₂₂ carboxylic acids, such as oleic acid, stearic acid, isostearic acid and palmitic acid. Zwitterionic surfactants are surface-active compounds that contain at least one quaternary ammonium group and at least one -COO ⁽⁾ - or -S0 ₃ ⁽⁾ group in the molecule. Particularly suitable zwitterionic surfactants are the so-called betaines, such as the N-alkyl-N, N-dimethylammonium glycinate, for example the cocoalkyl-dimethylammonium glycinate, N-acyl-aminopropyl-N, N-dimethylammonium glycinate, for example the cocoacylaminopropyl-dimethylammonium glycinate, and 2-alkyl-3-carboxymethyl-3-hydroxyethyl-imidazolines each having 8 to 18 carbon atoms in the alkyl or acyl group and the cocoacylaminoethylhydroxyethylcarboxymethylglycinate. A preferred zwitterionic surfactant is the fatty acid amide derivative known under the CTFA name Cocamidopropyl Betaine.

Ampholytic surfactants are understood to mean those surface-active compounds which, in addition to a C ₈ . ₁₈ -alkyl or -acyl group in the molecule contain at least one free amino group and at least one -COOH or -S0 ₃ H group and are capable of forming internal salts. Examples of suitable ampholytic surfactants are N-alkylglycines, N-alkylpropionic acids, N-alkylamino-butyric acids, N-alkyliminodipropionic acids, N-hydroxyethyl-N-alkylamidopropylglycines, N-alkyltaurines, N-alkyl sarcosines, 2-alkylaminopropionic acids and alkylamino acetic acids each about 8 to 18 carbon atoms in the alkyl group. Particularly preferred ampholytic surfactants are N-coconut alkyl aminopropionate, coconut acylaminoethyl aminopropionate and C _12-18 acyl sarcosine.

Nonionic surfactants contain z as a hydrophilic group. B. a polyol group, a polyalkylene glycol ether group or a combination of polyol and polyglycol ether group. Such connections are, for example

Addition products of 2 to 30 moles of ethylene oxide and / or 0 to 5 moles of propylene oxide with linear fatty alcohols with 8 to 22 carbon atoms, with fatty acids with 12 to 22 C atoms and on alkylphenols with 8 to 15 C atoms in the alkyl group,

C ₁₂ . ₂₂ fatty acid monoesters and diesters of adducts of 1 to 30 moles of ethylene oxide with glycerol,

C ₈ . ₂₂ alkyl mono- and oligoglycosides and their ethoxylated analogues, addition products of 5 to 60 mol ethylene oxide onto castor oil and hardened castor oil,

Addition products of ethylene oxide with sorbitan fatty acid esters Addition products of ethylene oxide with fatty acid alkanolamides.

Examples of the cationic surfactants which can be used in the processes according to the invention are, in particular, quaternary ammonium compounds. Ammonium halides such as alkyltrimethylammonium chlorides, dialkyldimethylammonium chlorides and trialkylmethylammonium chlorides, e.g. B. cetyltrimethylammonium chloride, stearyltrimethylammonium chloride, distearyldimethylammonium chloride, lauryldimethylammonium chloride, lauryldimethylbenzylammonium chloride and tricetylmethylammonium chloride. The quaternized protein hydrolyzates are further cationic surfactants which can be used according to the invention.

Also suitable according to the invention are cationic silicone oils, such as, for example, the commercially available products Q2-7224 (manufacturer: Dow Corning; a stabilized trimethylsilylamodimethicone), Dow Corning 929 emulsion (containing a hydroxylamino-modified silicone, which is also referred to as amodimethicone), SM -2059 (manufacturer: General Electric), SLM-55067 (manufacturer: Wacker) and Abil ^® -Quat 3270 and 3272 (manufacturer: Th. Goldschmidt; diquaternary polydimethylsiloxane, Quaternium-80).

In addition to a good conditioning effect, alkylamidoamines, especially fatty acid amidoamines such as the ^{stearylamidopropyldimethylamine} available under the name Tego Amid ^® S 18, are notable for their good biodegradability. Also very good biodegradability are quaternary Esterverbindungen, so-called "esterquats", such as those sold under the trademark Stepantex ^® methylhydroxyalkyldialkoyloxyalkylammonium.

An example of a suitable cationic surfactant quaternary sugar derivative is the commercial product Glucquat ^® 100, according to CTFA nomenclature a "lauryl methyl Gluceth-10 Hydroxypropyl Dimonium Chloride".

The compounds with alkyl groups used as surfactants can each be uniform substances. However, it is generally preferred to start from natural vegetable or animal raw materials in the production of these substances, so that substance mixtures with different alkyl chain lengths depending on the respective raw material are obtained.

In the case of the surfactants, which are addition products of ethylene and / or propylene oxide onto fatty alcohols or derivatives of these addition products, both products with a "normal" homolog distribution and those with a narrowed homolog distribution can be used. “Normal” homolog distribution is understood to mean mixtures of homologues which are obtained as catalysts when fatty alcohol and alkylene oxide are reacted using alkali metals, alkali metal hydroxides or alkali metal alcoholates. By contrast, narrow homolog distributions are obtained if, for example, hydrotalcites, alkaline earth metal salts of ether carboxylic acids, alkaline earth metal oxides,

hydroxides or alcoholates can be used as catalysts. The use of products with a narrow homolog distribution can be preferred.

Other active ingredients, auxiliaries and additives are, for example non-ionic polymers such as vinylpyrrolidone / vinyl acrylate copolymers, polyvinylpyrrolidone and vinylpyrrolidoneΛ / inylacetate copolymers and polysiloxanes, cationic polymers such as quaternized cellulose ethers, polysiloxanes with quaternary groups, dimethyldiallylammonium chloride polymers, dimethyldiallyl amide sulfonated polymers, acrylated amidyl amide sulfonated polymers, acrylated amidoxysulfonated polymers, acrylated amidoxylated copolymers, Dimethylaminoethyl methacrylate-vinylpyrrolidone copolymers,

Vinylpyrrolidone-imidazolinium methochloride copolymers and quaternized polyvinyl alcohol, zwitterionic and amphoteric polymers such as, for example, acrylamidopropyl trimethylammonium chloride / acrylate copolymers and octylacrylamide / methyl methacrylate / tert.-butylaminoethyl methacrylate / 2-hydroxypropyl acrylate polymers, for example polyacrylate, 2-hydroxypropyl acrylate polymers, crosslinked polyacrylic acids, vinyl acetate / crotonic acid copolymers, vinylpyrrolidone / inyl acrylate copolymers, vinyl acetate / butyl maleate / isobornyl acrylate copolymers, methyl vinyl ether / maleic anhydride copolymers and acrylic acid / ethyl acrylate / N-tert.-butyl acrylamides

Thickeners such as agar agar, guar gum, alginates, xanthan gum, gum arabic, karaya gum, locust bean gum, linseed gums, dextrans, cellulose derivatives, e.g. As methyl cellulose, hydroxyalkyl cellulose and carboxymethyl cellulose, starch fractions and derivatives such as amylose, amylopectin and dextrins, clays such as. B. bentonite or fully synthetic hydrocolloids such. B. polyvinyl alcohol, structurants such as glucose and maleic acid, hair-conditioning compounds such as phospholipids, for example soy lecithin, egg lecithin and cephalins, and silicone oils,

Protein hydrolyzates, in particular elastin, collagen, keratin, milk protein, soy protein and wheat protein hydrolyzates, their condensation products with fatty acids and quaternized protein hydrolyzates, perfume oils, dimethyl isosorbide and cyclodextrins, Solubilizers such as ethanol, isopropanol, ethylene glycol, propylene glycol, glycerin and diethylene glycol,

Anti-dandruff agents such as piroctone, olamine and zinc omadine, other substances for adjusting the pH value,

Active ingredients such as panthenol, pantothenic acid, allantoin, pyrrolidone carboxylic acids and their salts, plant extracts and vitamins, cholesterol, light stabilizers,

Consistency generators such as sugar esters, polyol esters or polyol alkyl ethers, fats and waxes such as walrus, beeswax, montan wax, paraffins, fatty alcohols and fatty acid esters, fatty acid alkanolamides,

Complexing agents such as EDTA, NTA and phosphonic acids, swelling and penetration substances such as glycerol, propylene glycol monoethyl ether, carbonates, hydrogen carbonates, guanidines, ureas and primary, secondary and tertiary phosphates, imidazoles, tannins, pyrrole, opacifiers such as latex,

Pearlescent agents such as ethylene glycol mono- and distearate, blowing agents such as propane-butane mixtures, N ₂ 0, dimethyl ether, CO ₂ and air, and antioxidants.

The constituents of the water-containing carrier are used for the production of the agents used in the process according to the invention in amounts customary for this purpose, e.g. For example, emulsifiers are used in concentrations of 0.5 to 30% by weight and thickeners in concentrations of 0.1 to 25% by weight of the total colorant.

For the coloring result it can be advantageous to add ammonium or metal salts. Suitable metal salts are e.g. B. formates, carbonates, halides, sulfates, butyrates, valerates, capronates, acetates, lactates, glycolates, tartrates, Citrates, gluconates, propionates, phosphates and phosphonates of alkali metals, such as potassium, sodium or lithium, alkaline earth metals, such as magnesium, calcium, strontium or barium, or of aluminum, manganese, iron, cobalt, copper or zinc, whereby sodium acetate, lithium bromide, calcium bromide , Calcium gluconate, zinc chloride, zinc sulfate, magnesium chloride, magnesium sulfate, ammonium carbonate, chloride and acetate are preferred. These salts are preferably present in an amount of 0.03 to 65, in particular 1 to 40, mmol based on 100 g of the total colorant used.

The pH of the ready-to-use coloring preparations is usually between 2 and 11, preferably between 5 and 9.

In the method according to the invention, the components and customary cosmetic ingredients are usually applied to the fibers containing keratin, left on the fiber for some time, usually about 30 minutes, and then rinsed out or washed out with a shampoo.

According to the invention, the 2-oxocarboxylic acid derivatives of the formula I and the compounds of component B are applied to the hair in one process step, ie. H. the components are applied together or in succession, but without pretreatment of the fiber by one of the components. The optionally contained ammonium or metal salts can be added to the first or the second component. Pretreatment of the fibers with the saline solution is not excluded.

The 2-oxocarboxylic acid derivatives of the formula I and the compounds of component B are preferably stored separately, either in a liquid to pasty preparation (aqueous or anhydrous) or as a dry powder. If the components are stored together in a liquid preparation, this should be largely anhydrous to reduce a reaction of the components. When stored separately, the reactive components only intimately mixed with one another immediately before use. In dry storage, a defined amount of warm (30 to 80 ° C) water is usually added before use and a homogeneous mixture is produced.

Examples

Preparation of a coloring solution

A slurry of 10 mmol of a 2-oxocarboxylic acid derivative of the formula I, if appropriate 10 mmol of an oxidation dye precursor, 10 mmol of sodium acetate and a drop of a 20% strength fatty alkyl ether sulfate solution in 100 ml of water was prepared. The slurry was heated to about 30 ° C and the pH was adjusted to 6.

A strand of 90% gray, untreated human hair was placed in this coloring solution at 30 ° C. for 30 minutes. The tress was then rinsed with lukewarm water for 30 seconds, dried with warm air and then combed out.

The respective color shades and color depths are shown in Table 1 below.

The color depth was rated on the following scale:

no or very pale color

(+) weak intensity

+ medium intensity

+ (+) medium to strong intensity ++ strong intensity

++ (+) strong to very strong intensity +++ very strong intensity Table 1

Discolorations with pyruvic acid Na salt

Table 2

Caiciumphenyl pyruvate discolouration

Table 3

Colorings with mesoxalic acid, di-Na salt

Table 4

Colorings with 2-hydroxyphenylglyoxylic acid, Na salt

Table 5

Colorings with 3-indolylglyoxylic acid

Table 6

Colorings with 2-furylglyoxylic acid

Table 7

Colorings with phenylglyoxylic acid

Claims

claims

1. A process for dyeing keratin-containing fibers, in particular human hair, in which (A) 2-oxocarboxylic acid derivatives having the formula (I)

wherein R ^{1 represents} a hydrogen atom, a C ₁ -C ₄ alkyl group, a carboxyl radical, a carboxylate radical, an aryl, benzyl or heteroaryl group which is represented by one or more C ₁ -C ₄ alkyl, C _r C ₄ - Alkoxy, CC ₄ hydroxyalkoxy, hydroxy, carboxy, sulfo or nitro group (s) may be substituted, X for O ^" , OH, a CC ₄ alkoxy or an NR ² R ³ group, in which R ² and R ^{3 are the} same or different and are hydrogen, CC ₄ alkyl or hydroxy-C ₂ -C ₄ alkyl, where if X is NR ² R ³ , the radicals R ² and R ³ also together with the Nitrogen atom can form a heterocyclic ring, in combination with

(B) at least one compound having a primary or secondary amino group or hydroxy group, selected from primary or secondary aliphatic or aromatic amines, nitrogen-containing heterocyclic compounds, from 2 to 9 amino acids and oligopeptides and aromatic hydroxy compounds, and / or at least one CH-active compound or that Reaction product from components A and B are applied to the fiber as a coloring component.

2. The method according to claim 1, characterized in that the 2-oxocarboxylic acid derivatives with the formula I are selected from pyruvic acid, glyoxylic acid, mesoxalic acid, phenylglyoxylic acid, 2-hydroxyphenylglyoxylic acid, phenylpyruvic acid, 4-nitrophenylglyoxylic acid, 4-methoxyphenylglyoxylic acid, 3-indolylglyoxylic acid and their sodium -, potassium and calcium salts and

6-methoxy-3-indolylglyoxylic acid and its amide, 2-furylglyoxylic acid and its amide, 3-indolylglyoxylic acid amide, 3-indolylglyoxylic acid dimethylamide and any mixtures thereof.

3. The method according to any one of claims 1 or 2, characterized in that the 2-oxocarboxylic acid derivatives with the formula I in an amount of 0.03 to 65 mmol, in particular from 1 to 40 mmol, based on 100 g of the entire colorant are.

4. The method according to any one of claims 1 to 3, characterized in that component B is selected from primary or secondary amines from the group consisting of N- (2-hydroxyethyl) -N-ethyl-, N- (2-methoxyethyl -), 2,3-, 2,4-, 2,5-dichloro-p-phenylene diamine, 2-chloro-p-phenylene diamine, N, N-bis (2-hydroxyethyl) -p-phenylene diamine, 2.5 -Dihydroxy-4-morpholinoaniline dihydrobromide, 2-, 3-, 4-aminophenol, o-, m-, p-phenylenediamine, 2,4-diaminophenoxyethanol, 2- (2,5-diaminophenyl) ethanol, 2.5 Diaminotoluene, phenol,

-phenethol, 4-methylamino-, 3-amino-4- (2'-hydroxyethyloxy) -, 3,4-methylenediamino-, 3,4-methylenedioxyaniline, 3-amino-2,4-dichloro-, 4- Methylamino, 2-methyl-5-amino, 3-methyl-4-amino, 2-methyl-5- (2-hydroxyoxyamino) -, 2-methyl-5-amino-4-chloro, 6 -Methyl-3-amino-2-chloro, 5- (2-hydroxyethylamino) -4-methoxy-2-methyl-, 2-amino-4- (2-hydroxyethylamino) -, 4-amino-2-aminomethyl- , 4-amino-2-hydroxymethyl phenol, 1, 3-diamino-2,4-dimethoxybenzene, 2-, 3-, 4-aminobenzoic acid, - phenylacetic acid, 2,3-, 2,4-, 2,5-, 3,4-, 3,5 -Diaminobenzoic acid, 4-, 5-aminosalicylic acid, 3-amino-4-hydroxy-, 4-amino-3-hydroxy-benzoic acid, 2-, 3-, 4-aminobenzenesulfonic acid, 3-amino-4-hydroxybenzenesulfonic acid, 4-amino -3-hydroxynaphthalene-sulfonic acid, 6-amino-7-hydroxynaphthalene-2-sulfonic acid, 7-amino-4-hydroxynaphthalene-2-sulfonic acid, 4-amino-5-hydroxynaphthalene-2,7-disulfonic acid, 3-amino-2 -naphthoic acid, 3-amino-phthalic acid, 5-aminoisophthalic acid, 1, 3,5-, 1, 2,4-triaminobenzene, 1, 2,4,5-tetraaminobenzene-tetrahydrochloride, 2,4,5-triaminophenol-trihydrochloride, 2,4,6-triaminoresorcinol trihydrochloride, 4,5-diaminobenzate catechol sulfate, 4,6-diaminopyrogallol dihydrochloride, 3,5-diamino-4-hydroxybrenzate catechol sulfate, aromatic nitriles, anilines, in particular nitro group-containing anilines, such as 4- Nitroaniline, 4-nitro-1,3-phenylenediamine, 2-nitro-4-amino-1- (2-hydroxyethylamino) benzene, 2-nitro-1-amino- 4- [bis- (2-hydroxyethyl) amino] benzene, 4-amino-2-nitrodiphenylamine-2'-carboxylic acid, 2-amino-6-chloro-4-nitrophenol, 1-amino-5-chloro -4- (2- hydroyethylamino) -2-nitrobenzene, aromatic anilines or phenols with a further aromatic radical such as 4,4'-diaminostilbene dihydrochloride, 4,4'-diaminostilbene-2,2'-disulfonic acid, Na salt , 4,4'-diaminodiphenyl methane, sulfide, sulfoxide, amine, 4,4'-diaminodiphenylamine-2-sulfonic acid, 4,4'-diaminobenzophenone, diphenyl ether, S.S '^^' - tetraaminodiphenyl tetrahydrochloride, 3,3 ', 4,4'-tetraamino-benzophenone, 1,3-bis (2,4-diaminophenoxy) propane tetrahydrochloride, 1,8-bis (2,5-diaminophenoxy) -3, 6-dioxaoctane-tetrahydrochloride, 1,3-bis- (4-aminophenylamino) propane, -2-propanol, 1,3-bis- [N- (4-aminophenyl) -2-hydroxyethylamino] -2-propanol, N , N-bis- [2- (4-aminophenoxy) ethyl] methylamine trihydrochloride, nitrogen-containing heterocyclic compounds selected from the group consisting of 2-, 3-, 4-amino, 2-amino-3-hydroxy-, 2,6-diamino, 2,5-di amino, 2,3-diamino, 2-dimethylamino-5-amino, 3-amino-2-methylamino-6-methoxy, 2,3-diamino-6-methoxy, 3,5-diamino-2 , 6-dimethoxy-, 2,4,5-triamino-, 2,6-dihydroxy-3,4-dimethylpyridine, 4,5,6- Triamino-, 2-hydroxy-4,5,6-triamino-, 4-hydroxy-2,5,6-triamino-, 2,4,5,6-tetraamino-, 2-methylamino-4,5,6- triamino-, 2,4-, 4,5-diamino-, 2-amino-4-methoxy-6-methyl-pyrimidine, 2,3,4-trimethylpyrrole, 2,4-dimethyl-3-ethylpyrrole, 3rd , 5-diaminopyrazole, -1, 2,4-triazole, 3-amino, 3-amino-5-hydroxypyrazole, 2-, 3-, 8-aminoquinoline, 4-amino-quinaldine, 2-, 6-amino- nicotinic acid, 5-aminoisoquinoline, 5-, 6-aminoindazole, 5-, 7-amino-benzimizazole, -benzothiazole, 2,5-dihydroxy-4-morpholinoaniline as well as indole and indoline derivatives, such as 4-, 5-, 6 -, 7-aminoindole, 4-, 5-, 6-, 7-hydroxyindole, 5,6-dihydroxyindole, 5,6-dihydroxyindoline and 4-hydroxyindoline, and in each case from the physiologically tolerable salts of these compounds formed with preferably inorganic acids, aromatic hydroxy compounds selected from the group consisting of 2-, 4-, 5-methylresorcinol, 2,5-dimethylresorcinol, resorcinol, 3-methoxyphenol, pyrocatechol, hydroquinone, pyrogallol, phloroglucinol, hydroxyhydroquinol on, 2-, 3-, 4-methoxy, 3-dimethylamino, 2- (2-hydroxyethyl) -, 3,4-methylenedioxyphenol, 2,4-, 3,4-dihydroxybenzoic acid, phenylacetic acid, gallic acid , 2,4,6-trihydroxybenzoic acid, - acetophenone, 2-, 4-chlororesorcinol, 1-naphthol, 1, 5-, 2,3-, 2,7-dihydroxynaphthalene, 6-dimethylamino-4-hydroxy-2-naphthalenesulfonic acid , 3,6-Dihydroxy-2,7-naphthalenesulfonic acid, and CH-active compounds selected from the group consisting of 1, 2,3,3-tetramethyl-3H-indolinium iodide, 1, 2,3,5-tetramethylindoiinium-p - toluenesulfonate, 1, 2,3,5-tetramethylindolinium methanesulfonate, 2,3-dimethyl-benzothiazolium iodide, 2,3-dimethyl-benzothiazolium-p-toluenesulfonate, rhodanine, rhodanine-3-acetic acid, 1-ethyl (methyl) - 2-quinaldinium iodide, barbituric acid, thiobarbituric acid, 1, 3-dimethyl (ethyl) -thiobarbituric acid, oxindole, coumaranone and 1-methyl-3-phenyl-2-pyrazolinone.

5. The method according to claim 4, characterized in that component B is selected from the group consisting of N- (2- Hydroxyethyl) -N-ethyl-, 2-chloro-p-phenylenediamine, N, N-bis- (2-hydroxyethyl) -p-phenylenediamine, 4-aminophenol, p-phenylenediamine, 2- (2,5-diaminophenyl) - ethanol, 2,5-diaminotoluene, 3,4-methylenedioxyaniline, 3-amino-2,4-dichloro-, 2-methyl-5-amino-, 3-methyl-4-amino-, 2-methyl-5- ( 2-hydroxyethylamino) -, 2-methyl-5-amino-4-chloro, 6-methyl-3-amino-2-chloro, 2-aminomethyl-4-amino, 2-hydroxymethyl-4-amino-, 2 -Amino-4- (2-hydroxyethylamino) phenol, 3,4-methylenedioxyphenol, 3,4-diaminobenzoic acid, 2,5-diamino, 2-dimethylamino-5-amino-, 3-amino-2-methyl - amino-6-methoxy-, 2,3-diamino-6-methoxy-, 3,5-diamino-2,6-dimethoxy-, 2,6-dihydroxy-3,4-dimethylpyridine, 2-hydroxy-4, 5,6-triamino, 4-hydroxy-2,5,6-triamino, 2,4,5,6-tetraamino, 2-methylamino-4,5,6-triamino-pyrimidine, 3,5-diaminopyrazole , 3-amino-5-hydroxypyrazole, 5,6-dihydroxyindole, 5,6-dihydroxyindoline, 1-naphthol, 1, 5-, 1, 6-, 1, 7-, 2,3-, 2,6-, 2,7-dihydroxynaphthalene and 2-naphthol-3,6-disulfonic acid Na salt, and in each case from the vo preferably physiologically tolerable salts of these compounds formed with inorganic acids.

6. The method according to any one of claims 1 to 5, characterized in that direct dyes from the group of nitrophenylenediamines, nitroaminophenols, anthraquinones or indophenols, preferably in an amount of 0.01 to 20 wt .-%, based on the total colorant , are used.

7. The method according to any one of claims 1 to 6, characterized in that ammonium or metal salts selected from the group of formates, carbonates, halides, sulfates, butyrates, valerates, capronates, acetates, lactates, glycolates, tartrates, citrates, gluconates, Propionates, phosphates and phosphonates of alkali metals, such as potassium, sodium or lithium, alkaline earth metals, such as magnesium, calcium, strontium or barium, or of aluminum, manganese, iron, cobalt, copper or zinc, are to be added.

8. The method according to any one of claims 1 to 7, characterized in that oxidizing agents, in particular H ₂ 0 ₂ , in an amount of 0.01 to 6 wt .-%, based on the application solution, are used.

9. The method according to any one of claims 1 to 8, characterized in that anionic, zwitterionic or nonionic surfactants are used.

10. The method according to any one of claims 1 to 9, characterized in that components A and B and other conventional cosmetic ingredients applied to the keratin fibers, some time, usually about 30 minutes, left on the fiber and then rinsed out or with be washed out with a shampoo.

11. Agent for dyeing keratin fibers, especially human hair, which contains as a coloring component

(A) one or more 2-oxocarboxylic acid derivatives with the formula I.

wherein R ^{1 represents} a hydrogen atom, a CC ₄ alkyl group, a carboxyl radical, a carboxylate radical, an aryl, benzyl or heteroaryl group, which is replaced by one or more CC ₄ alkyl, CC ₄ alkoxy, C ₁ -C ₄ -hydroxyalkoxy, hydroxy, carboxy, sulfo or nitro group (s) can be substituted, X for O ^" , OH, a C _r C ₄ alkoxy or an NR R ³ group in which R ² and R ^{3 are the} same or different and Is hydrogen, C _r C ₄ -alkyl or hydroxy-C ₂ -C ₄ -alkyl, where, when X is NR ² R ³ , the radicals R ² and R ^{3 can} also form a heterocyclic ring together with the nitrogen atom, ( B) at least one compound with a primary or secondary amino group or hydroxy group, selected from primary or secondary aliphatic or aromatic amines, nitrogen-containing heterocyclic compounds, from 2 to 9 amino acids and oligopeptides and aromatic hydroxy compounds, and / or at least one CH-active compound, where also the reaction product from components A and B can be contained.