SI8912492B - Procedure for leather dyeing - Google Patents

Claims (12)

A process for dyeing leather, characterized in that the leather is treated by an exhaustive process with a water fleet containing a preparation consisting essentially of a black anionic dye selected from the group consisting of acid dyes, direct dyes and complex metallic dyes and carbon black pigments; wherein the weight ratio of the anionic dye to the black pigment is from 95: 5 to 50:50. Process according to Claim 1, characterized in that the anionic dye corresponds to the formula * ¥ AN = N— / \ 4-H - \ - N = NZN = NB (1) • ·. · \ * Wherein one X is hydroxy and the other X is amino or hydrogen, A is optionally C1-C4-alkyl, C1-C4-alkoxy, halogen, trifluoromethyl, C1-C4-alkylsulfonyl, sulfamoyl, N-mono or N, N-di-C1-C4 -alkylsulfamoyl, carbamoyl, N-mono- or N, N-di-C1-C4-alkylcarbamoyl, sulfo, nitro, cyano, carboxy or phenoxy substituted phenyl or naphthyl residue, B means a phenyl or naphthyl residue containing at least one amino or hydroxy group as well as optionally further substituents selected from the group consisting of N-mono or N, N-di-C1-C4-alkylamino, phenylamino, o-, m- or p-methylphenylamino, unsubstituted or by methyl, chloro or nitro substituted benzoylamino, C1-C4-alkanoylamino or carboxymethylamino and the substituents mentioned above for A, Z represent the residue .✓4 \ y4 \ .__ / 4 \ / \ -8 ^ \ \ =. \ * a- / Λ-. χ or l -SO2NH-R2 denote R and R 'independently of one another hydrogen, sulfo, C1-C4-alkyl or C1-C4-alkoxy and n is 1 or 2. Process according to one of Claims 1 and 2, characterized in that the anionic dye corresponds to the formula A ί ί -N = N ~: ^ ^ pN = * N-Z '/ \ / \ s; ho3s N · * _ / * -SO3H -n = nb '(la), wherein A' is unsubstituted or halogen, nitro, sulfo, C1-C4-alkyl or C1-C4-alkoxy substituted phenyl radical, B 'is a phenyl radical, having a hydroxy or amino group and a further substituent selected from the group consisting of hydroxy, amino, phenylamino, O-, m- or p-methyl phenyl amino, C1-C4-alkoxy and phenoxy, Z 'represents a residue of formula \ / or t so2NH— ζ t where R " hydrogen, methyl, methoxy or sulfo and one X 'is hydroxy and the other X' is amino. Process according to Claim 1, characterized in that the anionic dye in the form of the free acid corresponds to the formula wherein D and D 'independently of one another, in each case optionally further represent sulfo, nitro, C 1 -C 4 -alkylsulfonyl, C 1 -C 4 -alkyl, halogen or unsubstituted or C 1 -C 4 -alkyl, C 1 -C 4 -alkoxy, sulfo, nitro or halogen substituted phenylase, a substituted benzene or naphthalene residue containing in the ortho position relative to the azo group containing a hydroxy group, K and K 'independently of one another the latter in each case represent a residue of a coupling component of a benzene or naphthalene type which, in the ortho position relative to the azo group, contains a hydroxy group and is optionally further substituted by amino, hydroxy, C1-C4-alkoxy, C1-C4-alkyl, C1-C4 -alkanoylamine, benzoylamine, sulfo, halogen or unsubstituted or C1-C4-alkyl, C1-C4-alkoxy, sulfo, nitro or halogen substituted phenylase, and Me stands for chromium or cobalt. Process according to one of Claims 1 or 4, characterized in that the anionic dye corresponds to the formula θ wherein Di and D2 represent, independently of one another, a residue of unsubstituted or with sulfo and / or nitro substituted 1-amino-2-hydroxynaphthalene or a residue of unsubstituted or with nitro, sulfo, chlorine, methyl, methoxy, methylsulfonyl or optionally with sulfo, methyl , methoxy, nitro or chlorine-substituted phenylase-substituted 2-amino-phenol and Ki and K2 stand independently for an unsubstituted or hydroxy, amino, sulfo or acetylamino-substituted 1- or 2-naphthol residue or for an unsubstituted or optionally with a methyl, methoxy, chlorine, sulfo or nitro substituted phenylase substituted resorcinol residue, and wherein the complex dye has 1 or 2 sulfo groups. Process according to one of Claims 1 to 5, characterized in that the pigment is a carbon black pigment. Process according to Claim 6, characterized in that the carbon black pigment has an average particle size of from 10 to 100 nm, preferably from 20 to 50 nm. Process according to Claim 1, characterized in that the preparation contains an anionic dye and a pigment in a weight ratio of 90:10 to 60:40. Process according to Claim 8, characterized in that the preparation contains a black anionic dye and a soot pigment in a weight ratio of 90:10 to 70:30. 10. A dye preparation characterized in that it consists essentially of a black anionic dye selected from the group consisting of acid dyes, direct dyes and metallic complex dyes, and a carbon black pigment in a weight ratio of 95: 5 to 50:50. Dye composition according to claim 10, comprising a black anionic dye of formula (1) or formula (2) and a carbon black pigment. Dye composition according to claim 10, comprising a black anionic dye of formula (Ia) or formula (2a) and a carbon black pigment in a weight ratio of 90: 10 to 60.40, preferably 80: 20 to 70: 30. For CIBA SPECIALTY CHEMICALS HOLDING INC .: