EP0181836B1 - Process for improving the light fastness of dyed leathers - Google Patents

Description

There are already z. B. from DE-C-417,209, DE-B-1,079,248, CH-A-261,948 or US-A-2,090,396 leather dyeings of anionic non-metallized dyes known, which are treated with metal salts during or after the dyeing. It is also known from US-A-2,908,543, leather dyeings of copper metal complex dyes to improve wet fastness and. a. post-treat with a copper compound.

The present invention relates to a process for improving the light fastness of leather dyed with anionic chromium or cobalt complex dyes, which is characterized in that the leather is treated with a compound of the copper before, during or after the dyeing.

As connections of the copper come z. B. salts of inorganic or organic acids and compounds which contain the metals mentioned in complexed form. Mixtures of these compounds are also suitable.

Preferably come e.g. B. the following compounds of copper in question: salts of inorganic acids, such as. B. copper chloride, sulfate, phosphate or nitrate; Salts of organic acids, such as. B. copper acetate, tartrate or salicylate, mixtures of different copper salts or mixtures of a copper salt and another acid, for. B. mixtures of copper acetate and salicylic acid can be used. Copper salts of salicylic acid derivatives or mixtures of the above-mentioned copper salts of inorganic or organic acids with salicylic acid derivatives are also suitable. Useful salicylic acid derivatives are e.g. B. 2-hydroxy-5-sulfobenzoic acid or compounds of formula I.

worin W, und W₂ unabhängig voneinander Wasserstoff, C,-C₄-Alkyl, Hydroxy-C,-C₄-alkyl oder gegebenenfalls durch Sulfo oder Carboxy substituiertes Phenyl bedeuten.

where W and W _{2 are} independently hydrogen, C, -C ₄ alkyl, hydroxy-C, -C ₄ alkyl or phenyl optionally substituted by sulfo or carboxy.

As complex compounds such. B. optionally sulfo-containing copper complexes of bisazomethines, acylhydrazones, semicarbazones and thiosemicarbazones of aromatic aldehydes or ketones in question.

Bisazomethines of aromatic aldehydes and ketones are understood to mean Schiff bases of aliphatic or aromatic diamines, the aldehydes and ketones having an OH group in the o-position to the formyl or acyl radical. The bond with the metal atom takes place via these two OH groups and the two nitrogen atoms in the bisazomethine part. Accordingly, these are tidentate ligands. The ligands preferably contain one or more sulfo groups which are located in the aldehyde or ketone part and / or in the bisazomethine bridge.

worin R, für Wasserstoff oder einen gegebenenfalls substituierten Alkyl- oder Arylrest steht, Y einen gegebenenfalls substituierten Alkylen- oder Arylenrest und Me Kupfer bedeutet und n = 1 bis 3 ist. Die Benzolringe A und B können ebenfalls und zwar unabhängig voneinander substituiert sein oder auch weitere ankondensierte Ringe aufweisen. Ausserdem können anstelle der Benzolringe A und B auch heterocyclische Ringe stehen.Apply z. B. bisazomethine metal complexes of formula II

in which R represents hydrogen or an optionally substituted alkyl or aryl radical, Y represents an optionally substituted alkylene or arylene radical and Me represents copper and n = 1 to 3. The benzene rings A and B can also, independently of one another, be substituted or also have further fused rings. In addition, the benzene rings A and B can also be heterocyclic rings.

If R denotes an optionally substituted alkyl radical, preference is given to a C ₁ to C ₈ alkyl radical, in particular a C ₁ to C ₄ alkyl radical, which can be branched or unbranched and optionally substituted, by halogen, such as fluorine or chlorine or bromine, C ₁ to C ₄ alkoxy, such as methoxy or ethoxy, by a phenyl or carboxyl radical, by C ₁ to C ₄ alkoxycarbonyl, such as. B. the acetyl radical or by hydroxy or a mono- or dialkylated amino group. In addition, the cyclohexyl radical can also be used, which can also be substituted, for example by C ₁ -C ₄ -alkyl or C ₁ -C ₄ -alkoxy.

If R _{1 is} an optionally substituted aryl radical, a phenyl or naphthyl radical is particularly suitable, which can be substituted by C 1 -C ₄ -alkyl, such as methyl, ethyl, propyl, Isopropyl, butyl, isobutyl, sec-butyl and tert-butyl, C, -C ₄ -alkoxy, such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy and tert-butoxy, halogen, such as Fluorine, chlorine and bromine, C ₂ -C ₅ alkanoylamino, such as acetylamino, propionylamino and butyrylamino, nitro, cyano, sulfo or a mono- or dialkylated amino group.

If Y is an alkylene radical, it is primarily a C ₂ to C ₄ alkylene radical, in particular a ―CH ₂ ―CH ₂ bridge. However, a C ₂ to C 8 alkylene chain which is interrupted by oxygen or, in particular, nitrogen is also suitable, in particular the - (CH ₂ ) ₃ ―NH― (CH ₂ ) ₃ bridge.

If Y is an arylene radical, it is primarily a phenylene radical, in particular an o-phenylene radical. This can also be substituted by C ₁ to C ₄ alkyl or C ₁ to C ₄ alkoxy.

Possible substituents for the benzene rings A and B are: C ₁ to C ₄ alkyl, C ₁ to C ₄ alkoxy, halogen, such as fluorine, chlorine or bromine, and also the cyano or nitro group.

In particular, the copper complexes of the formula 1 are used in the present process, in which R _{1 is} hydrogen, Y is the ethylene or o-phenylene bridge and n is 2, the two sulfo groups being in the benzene rings A and B, and especially here the complexes in which the sulfo groups are each arranged in p-position to the oxygen.

worin R₁ die vorstehend unter Formel II angegebene Bedeutung hat, Q Sauerstoff oder NH und n null oder 1 bedeutet, und R₂ für Wasserstoff oder einen gegebenenfalls substituierten Alkyl- oder Arylrest steht. Das Symbol Me bezeichnet wiederum Kupfer.The sulfo group-containing copper complexes of acylhydrazones of aromatic aldehydes and ketones are primarily complexes of the formula III

wherein R _{1 has} the meaning given above under formula II, Q is oxygen or NH and n is zero or 1, and R _{2 is} hydrogen or an optionally substituted alkyl or aryl radical. The symbol Me in turn denotes copper.

If R _{2 is} an alkyl radical, this can be branched. or be unbranched and has a chain length of preferably 1 to 8, in particular 1 to 4, carbon atoms. Suitable substituents are halogen, such as fluorine, chlorine or bromine, C ₁ to C ₄ alkoxy, such as methoxy or ethoxy, further phenyl or carboxyl, C, to C ₄ alkoxycarbonyl, such as. B. acetyl or hydroxy, mono- or dialkylamino.

If R _{2 is} an optionally substituted aryl radical, a phenyl or naphthyl radical, which can be substituted by C _1-4 alkyl, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl and tert .-butyl, C _1-4 alkoxy, such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy and tert-butoxy, halogen such as fluorine, chlorine and bromine, C ₂ - ₅ alkanoylamino, such as acetylamino, propionylamino and butyrylamino, nitro, cyano, sulfo or a mono- or dialkylated amino group.

Complexes of the formula III are preferably used in which R _{1 is} hydrogen and R _{2 is} hydrogen, methyl or in particular the phenyl radical and which contain copper as metal, especially the complexes in which the sulfo group in turn is in the p-position to the oxygen located.

worin R₁ die bereits im Zusammenhang mit der Formel 1 angegebene Bedeutung hat und X für Sauerstoff oder Schwefel steht. Me bezeichnet Kupfer.Copper complexes of semicarbazones or thiosemicarbazones are primarily understood to mean complexes of the formula IV

wherein R _{1 has} the meaning already given in connection with formula 1 and X represents oxygen or sulfur. Me denotes copper.

In addition to the transition metal complexes of the formulas III and IV, the ligands of which are derived from sulfosalicylaldehyde or the corresponding phenyl ketones, z. B. also those in which instead of mononuclear, multinuclear aromatic aldehydes and ketones, such as. B. 2-hydroxy-1-naphthaldehyde sulfonic acids were used to build up the ligand. In addition, it is pointed out that the fourth coordination point of the metal atom in the complexes of formulas III and IV by z. B. Water is occupied as a neutral ligand.

worin R₃ = H, OH, Alkyl oder Cycloalkyl bedeutet und worin der Ring A gegebenenfalls weitere Substituenten, wie z. B. Sulfo- oder Sulfonamidgruppen enthalten kann, im erfindungsgemässen Verfahren verwendbar.Furthermore, the copper complexes of compounds of formula V

wherein R ₃ = H, OH, alkyl or cycloalkyl and in which the ring A optionally further substituents, such as. B. sulfo or sulfonamide groups can be used in the inventive method.

Suitable alkyl radicals are those with 1 to 4 carbon atoms. Suitable cycloalkyl radicals are cyclohexyl and methylcyclohexyl radicals. Suitable substituents in ring A are e.g. As methyl, methoxy or chlorine. However, this ring is preferably unsubstituted.

worin R₄ = C₁-C₁₈-Alkyl oder Cycloalkyl bedeutet und die Ringe A und B durch C,-C₄-Alkyl, Cycloalkyl, C,-C₄-Alkoxy, Halogen oder OH substituiert sein können oder auch weitere ankondensierte Ringe aufweisen können. Ausserdem können anstelle der Ringe A und B auch heterocyclische Ringe stehen.In addition, compounds of the formula VI are suitable for the process according to the invention,

wherein R ₄ = C ₁ -C ₁₈ alkyl or cycloalkyl and the rings A and B can be substituted by C, -C ₄ alkyl, cycloalkyl, C, -C ₄ alkoxy, halogen or OH or also further fused rings can have. In addition, rings A and B can also be heterocyclic rings.

The complex compounds mentioned, which have sulfo groups, are preferably used as the alkali, especially sodium, or amine salt.

The preferred compounds for the process according to the invention are copper (II) chloride, sulfate, nitrate or acetate and mixtures of these salts with tartaric acid or salicylic acid.

The metal compounds are expediently applied from an aqueous bath in an amount of 0.1 to 10% by weight, preferably 0.5 to 5% by weight, based on the weight of the leather.

The treatment with the metal compound can take place before, during or after the coloring. After the leather has been dyed and rinsed, an aftertreatment is preferably carried out in a fresh, aqueous liquor containing the metal compound and, if appropriate, acids and / or salts to adjust a certain pH.

The treatment takes place e.g. B. at a pH between 3 and 7 at 20 to 100 ° C for about 10 to 60 minutes.

The dyeings of the leather can be produced in a conventional manner with the usual anionic chromium or cobalt complex leather dyes.

The anionic chromium or cobalt complex dyes are, for example, salts of chromium or cobalt-containing mono-, dis- or polyazo dyes including the azomethine and formazan dyes as well as the anthraquinone, xanthene, nitro, triphenylmethane, naphthoquinoneimine and phthalocyanine dyes. The anionic character of these dyes can be caused by metal complex formation alone and by acidic, salt-forming substituents, such as carboxylic acid groups, sulfuric acid and phosphonic acid ester groups, phosphonic acid groups, alkylsulfone, sulfonamido or sulfonic acid groups. The 1: 1 or 1: 2 metal complex dyes are preferred. The 1: 1 metal complex dyes preferably have one or two sulfonic acid groups. In particular, they contain chromium as metal.

The 1: 2 metal complex dyes contain a cobalt or in particular a chromium atom as the central atom. Two complex-forming components are connected to the central atom, at least one of which is a dye molecule, but preferably both are dye molecules. The two dye molecules involved in the complex formation can be the same or different from one another. The 1: 2 metal complex dyes can e.g. B. contain two azomethine molecules, an azo and an azomethine dye or two azo dyes, which dyes can be substituted with further arylazo and / or arylazoaryleno groups. Aryl here means above all benzene or naphthalene residues, which may be substituted, e.g. B. by nitro, sulfo, halogen, alkyl or alkoxy. The azo or azomethine dye molecules can have water solubilizing groups such as. B. acid amide, alkylsulfonyl or the above acid groups. Preference is given to 1 2-cobalt or 1: 2 chromium complexes of monoazo dyes which have acid amide, alkylsulfonyl or sulfonic acid groups.

worinParticularly suitable dyes correspond to formula VII

wherein

Z independently of one another is nitrogen or a CH group,

A and C independently of one another each a residue of the benzene or naphthalene series which contains a hydroxyl or carboxy group in the o-position to the azo or azomething group,

B and D each independently of the other the rest of a coupling component when Z is nitrogen, the coupling component in the o- or a-position to the azo group contains the group X, or independently the rest of an o-hydroxyaldehyde if Z is the CH group represents

X ₁ independently of one another each represent oxygen or a group of the formula -NR _S -, in which R _{s represents} hydrogen or a C ₁ -C ₄ alkyl group,

Me ₁ chrome or cobalt,

• p 1 oder 2 und
• m eine ganze Zahl von 0 bis 6 bedeutet.

Y is the S0 ₃ H, COOH, P0 ₃ H ₂ or SO ₂ ―V group, where VC, -C ₄ alkyl, optionally substituted by halogen, vinyl, amino, N-mono- or N, N- Dialkylamino means

• p 1 or 2 and
• m is an integer from 0 to 6.

Suitable dyes of the formula VII are both symmetrical and asymmetrical 1: 2 azo or 1: 2 azomethine complexes and 1: 2 complexes which contain an azo and an azomethine dye bonded to the metal.

Of the dyes of the formula VII, those in which X is oxygen are preferably used.

If dyes of the formula VII have several groups Y, these can be the same or different. However, preferably all Y S0 represent ₃ H groups.

Furthermore, dyes of the formula VII in which p is 1 and those in which m is 1 to 3, preferably 2, are preferably used.

The radicals A and C can also be further substituted by groups Y, in particular with C _i -C ₄ alkyl or alkoxy, chlorine or nitro.

Suitable diazo components A and C are e.g. E.g .: anthranilic acid, 4- or 5-sulfoanthranilic acid, 2-amino-1-hydroxybenzene, 4-chloro- and 4,6-dichloro-2-amino-1-hydroxybenzene, 4- or 5-nitro-2-amino- 1-hydroxybenzene, 4-chloro and 4-methyl-6-nitro-2-amino-1-hydroxybenzene, 6-chloro-4-nitro-2-amino-1-hydroxybenzene, 4-cyano-2-amino-1 -hydroxybenzoi, 4-methoxy-2-amino-1-hydroxybenzene, 4-methoxy-5-chloro-2-amino-1-hydroxybenzene, 4-methyl-2-amino-1-hydroxybenzene, 4-chloro-5-nitro -2-amino-1-hydroxybenzene, 3,4,6-trichloro-2-amino-1-hydroxybenzene, 4,6-dinitro-2-amino-1-hydroxybenzene, 2-amino-l-hydroxybenzene-4- or -5-sulfonic acid, 4-nitro-2-amino-1-hydroxybenzene-6-sulfonic acid, 5-nitro- or 6-nitro-2-amino-1-hydroxybenzene-4-sulfonic acid, 6-chloro-2-amino- 1-hydroxybenzene-4-sulfonic acid, 4-chloro-2-amino-1-hydroxybenzene-6-sulfonic acid, 1-amino-2-hydroxy-naphthalene-4-sulfonic acid, 1-amino-2-hydroxy-6-nitronaphthalene 4-sulfonic acid, or 2-amino-1-hydroxybenzene-4,6-disulfonic acid, 1-amino-2-hydroxybenzene-4-sulfonic acid amide, 4-methylsulfonyl-2-amino-1-hydroxybenzene, 4- (2 ' -, 3'- or 4'-sulfophenylazo) -2-amino-1-hydroxybenzene, 4- (3'-sulfonamidophenylazo) -2-amino-1-hydroxybenzene, 4- (4'-phenylazophenylazo) -2-amino- 1-hydroxybenzene, 1-amino-2-hydroxy-5-sulfonic acid antanilide or 1-amino-2-hydroxy-5- (2'-sulfo) sulfonic acid anilide.

A and C preferably each independently represent the radical of a 1-hydroxy-2-aminobenzene, which is optionally substituted one or more times by identical or different substituents from the series nitro, sulfo, chlorine, methyl or methoxy, and in particular the radical a 1-hydroxy-2-aminobenzene which carries a nitro group in the 4- or 5-position or the remainder of a 1-hydroxy-2-aminobenzene which carries a nitro group in the 4-position and a sulfo group in the 6-position, or the Residue of a 1-hydroxy-2-aminobenzene, which carries a sulfo group in the 4-position and a nitro group in the 6-position.

The radicals B and D are preferably derived from the following groups of coupling components: phenols which are optionally substituted by low molecular weight alkyl or alkoxy, amino or acylamino and which are coupled in the o-position, where acylamino is C ₁ -C ₄ -alkanoylamino-, C ₁ -C ₄ -Alkylsulfonylamino-, C, -C ₄ -Alkoxycarbonylamino-, Aroylamino- or Arylsulfonylaminoreste means resorcinol, m-phenyienediamine, optionally substituted in the 4-position by sulfo, chlorine, methyl or methoxy, naphthols, optionally with C ₁ -C ₄ -Alkyl or alkoxy, chlorine, amino, acylamino or sulfo are substituted, where acylamino has the same meaning as given above, 5-pyrazolones or 5-aminopyrazoles, which in the 1-position one optionally with chlorine, nitro, C ₁ -C ₄ -alkyl or alkoxy groups or sulfo groups have substituted phenyl or naphthyl and have a C, -C ₄ alkyl group in the 3-position, in particular a methyl group.

Acetoacetic acid amides, acetoacetic acid anilides and benzoylacetic acid anilides, which may be substituted in the anilide core with chlorine, C, -C ₄ alkyl or alkoxy or sulfo groups, or 6-hydroxy-3-cyano or 6-hydroxy-3-carbonamido-4- alkyl-2-pyridones, which are in the 1-position by optionally substituted C ₁ -C ₄ -alkyl, e.g. B. methyl, isopropyl, ß-hydroxyethyl, ß-aminoethyl or γ-isopropoxypropyl or substituted by phenyl, and in the 4-position can carry a C, -C ₄ alkyl group, especially methyl.

Examples of such coupling components are: 2-naphthol, 1,3- or 1,5-dihydroxynaphthalene, 1-naphthol, 1-acetylamino-7-naphthol, 1-propionylamino-7-naphthol, 1-carbomethoxyamino-7-naphthol, 1- Carboethoxyamino-7-naphthol, 1-carbopropoxyamino-7-naphthol, 6-acetyl-2-naphthol, 2-naphthol-3-, -4-, -5-, -6-, -7- or -8-sulfonic acid, 1-naphthol-3-, -4- or -5-sulfonic acid, 1-naphthol-3,6-disulfonic acid, 1-naphthol-4,8-disulfonic acid, 1-naphthol-3,8-disulfonic acid, 2-naphthol- 3,6-disulfonic acid, 4-methyl-1-naphthol, 4-methoxy-1-naphthol, 4-acetyl-1-naphthol, 5,8-dichloro-1-naphthol, 5-chloro-1-naphthol, 2- Naphthylamine, 2-naphthylamine-1-sulfonic acid, 1-naphthylamine-4- or -5-sulfonic acid, 2-aminonaphthalene-6- or -5-sulfonic acid, 1-phenyl-3-methylpyrazol-5-one, 1-phenyl- 5-pyrazolon-3-carboxamide, 1- (2'-, 3'- or 4'-methylphenyl) -3-methylpyrazol-5-one, 1- (2 ', 3'- or 4'-sulfophenyl) -3 -methylpyrazol-5-one, 1- (2'-chloro-5'-sulfophenyl) -3-methylpyrazol-5-one, 1- (2'- or 4'-methoxyphenyl) -3-methylpyrazol-5-one, 1 - (2'-, 3'- or 4'-chlorophenyl) -3-methylpyrazol-5-one, 1- (2'-, 3'- or 4'-nitrophenyl) -3-methylpyrazol-5-one, 1 - (2'-, 5'- or 3 ', 4'-dichlorophenyl) -3-methylpyrazol-5-one, 1- (2', 5'-dichloro-4'-sulfophenyl) -3-methyl-pyrazole- 5-one, 1- (2'-3'-or 4'-sulfophenyl) -3-methyl-5-aminopyrazole, 1- (2'-chloro-5'-sulfophenyl) -3-methyl-5-aminopyrazole, Acetoacetanilide, acetoacetanilide-2-, -3- or -4-sulfonic acid, acetoacet-o-anisidide, acetoacet-o-toluidide, acetoacet-o-chloroanilide, acetoacet-m-xylidide, tetralol, 4-methylphenol, 3-dialkylaminophenol, especially 3-dimethylamino and 3-diethylaminophenol, 4-butylphenol, 4-amylphenol, especially 4-t-amylphenol, 2-isopropyl-4-methylphenol, 2- or 3-acetylamino-4-methylphenol, 2-methoxycarbonylamino 4-methylphenol, 2-ethoxycarbonylamino-4-methylphenol and 3,4-dimethylphenol, resorcinol, 1-ethyl-3-cyano-4-methyl-6-hydroxypyridone, 1-methyl-3-cyano-4-methyl-6- hydroxypyridone, 1-phenyl-3-carbonamido-4-methyl-6-hydroxypyridone.

B or D is preferably a 1- or 2-naphthol, optionally substituted with a sulfo group, m-phenylenediamine, resorcinol, p-alkyl (C ₁ -C ₄ ) phenol, 1-phenyl-3-methyl-5-pyrazolone or acetoacetic anilide, where the phenyl group in the latter two compounds can be substituted by C ₁ -C ₄ alkyl, C, -C ₄ alkoxy, chlorine or sulfo.

If Z is the —CH group, B or D represents the residue of an o-hydroxyaldehyde, preferably an o-hydroxybenzaldehyde or o-hydroxynaphthaldehyde. Suitable aldehydes are, for example: 2-hydroxy-1-naphthaldehyde, 1-hydroxy-2-naphthaldehyde, 2-hydroxy-benzaldehyde, 3- and 5-methyl-2-hydroxybenzaldehyde, 3,5-dimethyl-2-hydroxybenzaldehyde, 5- Butyl-2-hydroxybenzaldehyde, 5-chloro or 5-bromo-2-hydroxybenzaldehyde, 3-chloro-2-hydroxybenzaldehyde, 3,5-dichloro-2-hydroxybenzaldehyde, 5-sulfo-2-hydroxybenzaldehyde, 3-methyl-5 -chloro-2-hydroxybenzaldehyde, 5- (phenylazo) -2-hydroxybenzaldehyde, 5- (2'-, 3'- or 4'-sulfophenylazo) -2-hydroxybenzaldehyde, 5- (6'-sulfonaphthyl-1'-azo ) -2-hydroxybenzaldehyde or 5- (4 "-sulfo-4'-phenylazo) -phenylazo-2-hydroxybenzaldehyde.

entsprechen, worinThe dyes used are preferably symmetrical 1: 2 metal complexes with 2 sulfo groups, and dyes which are of the formula VIII are particularly preferred

correspond to what

Z independently of one another is a CH group or preferably nitrogen,

A 'and C' each represent the residue of a 1-hydroxy-2-aminobenzene which carries a nitro group in the 4- or 5-position, or the residue of a 1-hydroxy-2-aminobenzene which has a nitro group in the 4-position and bears a sulfo group in the 6 position or the remainder of a 1-hydroxy-2-aminobenzene which bears a nitro group in the 6 position and a sulfo group in the 4 position,

B 'and D' each independently represent the remainder of one of the following coupling components if Z is nitrogen: 1- or 2-naphthol optionally substituted with a sulfo group, m-phenylenediamine, resorcinol, p-alkyl (C ₁ -C ₆ ) - Phenol, 1-phenyl-3-methyl-5-pyrazolone or acetoacetic anilide, it being possible for the phenyl group in the latter two compounds to be substituted by C ₁ -C ₄ alkyl, C ₁ -C ₄ alkoxy, chlorine or sulfo, or, if Z is the CH group, the remainder of an o- Hydroxybenzaldehyde or o-hydroxynaphthaldehyde, which can be substituted by phenylazo or sulfophenylazo,

Me ₁ cobalt or chrome and

Ka ^{⊖ means} a cation.

worin q eine ganze Zahl von 0 bis 2, Me₁ Kobalt oder Chrom, Ka^⊕ ein Kation und Y Methyl, ―CONH₂ oder -CO-NHR bedeutet, wobei R eine Alkylgruppe mit 1 bis 4 C-Atomen darstellt, oder der Formel X

worin X₂ Wasserstoff, Chlor, Methyl oder Methoxy, Me₁ Kobalt oder Chrom und Ka^⊕ ein Kation bedeutet, oder der Formel XI

worin q eine ganze Zahl von 0 bis 2 und Ka^⊕ ein Kation bedeutet,Particularly preferred dyes correspond to formula IX

wherein q is an integer from 0 to 2, Me ₁ cobalt or chromium, Ka ^{⊕ is} a cation and Y is methyl, ―CONH ₂ or -CO-NHR, where R is an alkyl group having 1 to 4 carbon atoms, or the formula X

wherein X _{2 is} hydrogen, chlorine, methyl or methoxy, Me ₁ cobalt or chromium and Ka ^{⊕ is} a cation, or the formula XI

in which q is an integer from 0 to 2 and Ka ^{⊕ is} a cation,

worin

• A₁ den Rest von 1-Hydroxynaphthalin oder 2-Hydroxynaphthalin,
• R₆ Wasserstoff, Chlor oder Methyl,
• R₇ Wasserstoff, Nitro oder Chlor und
• Ka^⊕ ein Kation bedeutet, und

von den Substituenten X₃, X₄ und X₅ einer eine S0₃-Gruppe und die beiden anderen Wasserstoff darstellen, wobei X₅ Wasserstoff ist, wenn R₆ Chlor und R₇ Wasserstoff bedeutet, oder der Formel XIII

worin X₆ Wasserstoff, Chlor oder Nitro und Ka^⊕ ein Kation bedeutet und worin die Sulfogruppe im Pyrazolonfarbstoff im Ring A oder B und die Nitrogruppe im Ring A dieses Farbstoffes in 4-, 5- oder 6-Stellung des 1-Hydroxy-2-aminobenzols angeordnet ist, oder der Formel XIVor the formula XII

wherein

• A _{1 is} the remainder of 1-hydroxynaphthalene or 2-hydroxynaphthalene,
• R _{6 is} hydrogen, chlorine or methyl,
• R _{7 is} hydrogen, nitro or chlorine and
• Ka ^{⊕ means} a cation, and

one of the substituents X ₃ , X ₄ and X _{5 is} an S0 ₃ group and the other two are hydrogen, where X _{5 is} hydrogen if R _{6 is} chlorine and R _{7 is} hydrogen, or of the formula XIII

in which X _{6 is} hydrogen, chlorine or nitro and Ka ^{⊕ is} a cation and in which the sulfo group in the pyrazolone dye in ring A or B and the nitro group in ring A of this dye in the 4-, 5- or 6-position of 1-hydroxy-2- aminobenzene is arranged, or the formula XIV

(See Formula XIV page 9 f.)

worin X_s Wasserstoff, Chlor oder Nitro, Ka^⊕ ein Kation und A, den Rest von 1-Hydroxynaphthalin oder 2-Hydroxynaphthalin bedeutet.

wherein X _{s is} hydrogen, chlorine or nitro, Ka ^{⊕ is} a cation and A, the rest of 1-hydroxynaphthalene or 2-hydroxynaphthalene.

By treatment with the metal compounds, the dyeings on leather with the dyes described above are improved in lightfastness, e.g. B. by evaluating the light fastness according to SNV No. 95.809 by approx. 1 to 2 notes.

The process according to the invention is particularly suitable for improving the light fastness of leather dyeings which have been obtained with a mixture of a yellow, a red and a blue dye of the type indicated above (i.e. with a trichrome).

The following examples serve to illustrate the invention. Parts mean parts by weight and percentages percent by weight. The temperatures are given in degrees Celsius.

Example 1 -

100 parts of prewashed furniture leather are mixed for 60 minutes at 40 ° in a solution of 150 parts of water, 5 parts of tanning agent A (formaldehyde condensation product of phenolic sulfonic acids) and 5 parts of tanning agent B (condensation product of a urea derivative with phenolic sulfonic acids) at 24 revolutions per Minute retanned.

The leather is then rinsed and then neutralized in a fresh liquor of 200 parts of water, 2 parts of a neutralizing agent based on ammonium salts of aromatic sulfonic acids and aliphatic dicarboxylic acids and 2.5 parts of sodium bicarbonate at 30 ° for a total of 60 minutes.

1 : 2-Kobaltkomplex gelöst in 50 Teilen Wasser, sowie 0,5 Teile eines Egalisierungsmittels vom Typ Alkylaminopolyglykoläther hinzugefügt. Nach weiteren 30 Minuten werden dem Färbebad ausserdem 10 Teile eines Fettungsmittelgemisches aus gleichen Teilen eines sulfitierten Seetieröls und einer Formulieruug auf Basis von sulfierten Kohlenwasserstoffen, Fettsäuren und deren Derivaten zugesetzt. Nach der Fettungsmittelzugabe wird 60 Minuten bei unveränderter Temperatur weitergefärbt. Dann wird mit 1 Teil Ameisensäure 85 %ig angesäuert und die Färbung noch 30 Minuten bei 50° fortgesetzt.After the neutralization, 2 parts of ammonia is then rinsed again and preparation for the dyeing 15 minutes at 50 in an ammoniacal ^6, consisting of 150 parts water, 24% ig and 3 parts of the tanning agent B existing dye liquor pre-run. Then 1.3 parts of the yellow dye of the formula

1: 2 cobalt complex dissolved in 50 parts of water and 0.5 part of a leveling agent of the alkylaminopolyglycol ether type added. After a further 30 minutes, 10 parts of a fatliquor mixture of equal parts of a sulfited marine oil and a formulation based on sulfated hydrocarbons, fatty acids and their derivatives are also added to the dyebath. After adding the lubricant, dyeing is continued for 60 minutes at the same temperature. Then it is acidified with 1 part of 85% formic acid and the dyeing is continued for 30 minutes at 50 °.

The dyed leather is then post-treated for 30 minutes in a new post-treatment bath consisting of 200 parts of water at 50 ° and 3 parts of a mixture of copper acetate and salicylic acid in a molar ratio of 1: 2, adjusted to pH 4.5 with formic acid. It is then finished as usual and a section of the aftertreated dyeing together with a section of a similar but not aftertreated dyeing is exposed in a Xenotest 450 from the quartz lamp company Hanau (FRG) for 200 hours. The light fastness is assessed with the aid of an ISO blue scale, which is also exposed at the same time, with 8 colorations graded in light fastness. It can be seen that the coloring aftertreated with the copper compound has a significantly improved light fastness.

Example 2

1 : 2-KobaltkomplexThe procedure is the same as in Example 1, except that a dye mixture of 1.0 part of the yellow-brown dye of the formula is used to dye the retanned leather

1: 2 cobalt complex

1 : 2-Chromkomplex und 0,05 Teilen des blauen Farbstoffes der Formel

1 : 2-Chromkomplex verwendet wird. Die resultierende braune Färbung wird anschliessend wie im Beispiel 1 beschrieben mit 3 Teilen einer Mischung aus Kupferacetat und Salicylsäure nachbehandelt und dann gleichzeitig mit einer entsprechenden nicht nachbehandelten Färbung unter identischen Bedingungen im Xenotest 450 belichtet. Nach Abschluss der Belichtung werden die beiden Färbungen verglichen, wobei sich zeigt, dass die mit der Kupferverbindung nachbehandelte Färbung eine deutlich bessere Lichtechtheit aufweist.0.05 part of the red dye of the formula

1: 2 chromium complex and 0.05 part of the blue dye of the formula

1: 2 chrome complex is used. The resulting brown color is then post-treated as described in Example 1 with 3 parts of a mixture of copper acetate and salicylic acid and then exposed simultaneously to a corresponding non-post-treated color under identical conditions in the Xenotest 450. After completion of the exposure, the two colorings are compared, which shows that the coloration aftertreated with the copper compound has a significantly better lightfastness.

An aftertreatment with 3% (based on the leather) copper tartrate or 3% copper sulfate brings about a similar improvement in light fastness as an aftertreatment with 3% of the mixture of copper acetate and salicylic acid.

Example 3

1 : 2-Kobaltkomplex eingesetzt werden. Die gelbbraune Färbung wird anschfiessend mit 3 Teilen Kupfertartrat wie im Beispiel 1 beschrieben nachbehandelt und dann zur Bestimmung der Lichtechtheit im Xenotest 450 belichtet.The retanned furniture leather is dyed in a manner analogous to that in Example 1, but using 0.7 part of the dye of the formula instead of the yellow dye

1: 2 cobalt complex can be used. The yellow-brown color is then aftertreated with 3 parts of copper tartrate as described in Example 1 and then exposed in the Xenotest 450 to determine the light fastness.

The lightfastness of the aftertreated dye is significantly better than the lightfastness of the nontreated dye.

Instead of copper tartrate, 3% of a mixture of copper acetate and salicylic acid in a molar ratio of 1: 2 can be treated with an equally good result.

Example 4

The black coloring used for this example is produced as follows:

100 parts of the non-intermediate dried furniture leather are washed in 300 parts of water and 0.6 part of 40% acetic acid for 10 minutes at 30 °. Then 3 parts of a surface lubricant consisting of chlorinated hydrocarbons and n-alkyl derivatives are added and the mixture is left to run for a further 30 minutes. It is then neutralized in a fresh liquor consisting of 200 parts of water at 30 ° and 2 parts of a neutralizing agent based on ammonium salts of aromatic sulfonic acids and aliphatic dicarboxylic acids. After 15 minutes of treatment, 3 parts of a polymer tanning agent are added, and after a further 20 minutes, 2 parts of sulfited marine oil, followed by 2.5 parts of sodium bicarbonate. The neutralization then continues for 45 minutes.

After neutralization, the mixture is washed again with 300 parts of water at 50 ° for 10 minutes.

To dye the leather, a dyeing liquor is prepared from 200 parts of water at 50 °, 1 part of ammonia 24% and 1 part of the neutralizing agent mentioned above. The neutralized leather is left to run for 10 minutes in this liquor. Then 0.9 parts of the black dye of the formula

und 0,5 Teile Egalisiermittel vom Typ Alkylaminopolyglykoläther beigefügt. Nach einer Färbezeit von 30 Minuten erfolgt die Zugabe eines Fettungsmittelgemisches aus 2 Teilen sulfitiertem Seetieröl, 2 Teilen sulfitierten Fettsäureestern und animalischen Fettstoffen und 2 Teilen einer Formulierung auf Basis von sulfierten Kohlenwasserstoffen, Fettsäuren und deren Derivaten. Nach abermals 30 Minuten werden ausserdem 4 Teile Weissgerbstoff (Kondensationsprodukt eines Harnstoffderivates mit phenolischen Sulfosäuren) und nach weiteren 45 Minuten noch 1,25 Teile Ameisensäure 85 %ig hinzugefügt.

and 0.5 parts of alkylaminopolyglycol ether-type leveling agent are added. After a dyeing time of 30 minutes, a fatty compound mixture consisting of 2 parts of sulfited marine oil, 2 parts of sulfited fatty acid esters and animal fatty substances and 2 parts of a formulation based on sulfated hydrocarbons, fatty acids and their derivatives is added. After another 30 minutes, 4 parts of white tanning agent (condensation product of a urea derivative with phenolic sulfonic acids) are also added, and after a further 45 minutes, 1.25 parts of 85% formic acid are added.

After a final treatment period of 30 minutes, the liquor is drained off and replaced by a new one consisting of 0.4 part of the black dye listed above and 200 parts of water at 50 °. It is dyed for another 20 minutes. Then 2 parts of fatliquor based on natural and modified oils and fats as well as n-alkyl derivatives and 1.5 parts of a grip improver consisting of a fatty acid-polyamide condensation product are added. After a further 20 minutes, the mixture is acidified with 1 part of 85% formic acid and then further stained for another 20 minutes.

The black leather dyeing is then treated as described in Example 1 in a fresh bath with 3 parts of the mixture of copper acetate and salicylic acid at 50 °. Then the leather is finished as usual and exposed in the Xenotest.

The lightfastness of the aftertreated dye is significantly better than the lightfastness of a nontreated dye.

Example 5

If the procedure is as described in Examples 1 to 4, but only 0.1% (based on the weight of the leather) of the copper compounds is used, an improvement in the light fastness is also obtained.

Example 6

100 parts of non-intermediate-dried furniture leather are retanned for 90 minutes in a fleet consisting of 200 parts of water at 50 ° and 8 parts of a condensation product of formaldehyde and phenolic sulfonic acids.

The leather is then washed in 500 parts of water at 30 ° for 15 minutes and then in a liquor composed of 300 parts of water at 30 ° and 1.5 parts of sodium formate, to which 2.5 parts of sodium bicarbonate are also added after 10 minutes, 80 Neutralized for minutes. Following neutralization, there is again a 10-minute washing operation in 500 parts of 40 ° water.

The leather treated in this way is then dyed in a liquor consisting of 200 parts of water, 2 parts of 24% ammonia and 1.0 part of the yellow dye used in Example 1 for 30 minutes at 40 °. Then a coloring agent mixture consisting of 8 parts of a formulation of sulfited hydrocarbons, fatty acids and their derivatives and 4 parts of sulfited oil and, after a further 90 minutes, 3 parts of 85% formic acid are added to the dye liquor. The dyeing is then continued for 30 minutes at the same temperature.

The dyed and greased leather is then in a new aftertreatment bath adjusted to pH 5 with formic acid, consisting of 200 parts of water at 50 ° and 1.0 part of the copper compound of the formula

30 Minuten nachbehandelt. Dann wird wie üblich fertiggestellt und ein Abschnitt der nachbehandelten Färbung zusammen mit einer gleichartigen, aber nicht nachbehandelten Färbung 100 Stunden in einem Xenotest 450 Belichtungsapparat belichtet. Dabei kann festgestellt werden, dass die mit der Kupferverbindung nachbehandelte Färbung eine deutlich bessere Lichtechtheit besitzt.

Treated for 30 minutes. It is then finished as usual and a section of the post-treated dye is exposed together with a similar but not post-treated dye for 100 hours in a Xenotest 450 exposure apparatus. It can be determined that the coloring aftertreated with the copper compound has a significantly better light fastness.

If the aftertreatment is not carried out in a new bath as described above but immediately after dyeing and greasing in the dye bath itself, a similar improvement in light fastness is obtained. In this case, the pH of the treatment liquor is approximately 4 and the temperature is 40 °, due to the dyeing process.

The copper compound of the above formula is made as follows:

2.24 parts of the sodium salt of 2-hydroxybenzaldehyde-5-sulfonic acid are dissolved in 20 parts of water at 70 °. After adding 1.36 parts of benzoic acid hydrazide, the reaction mixture is kept at 90 to 95 ° for 1 hour, a clear, yellow solution of the hydrazone compound being formed. For the conversion into the copper complex, the solution obtained is mixed with a solution of 1.7 parts of C _U C1 ₂ -2H ₂ 0 and 4 parts of crystallized sodium acetate in 10 parts of water and then kept at 70 to 75 ° for 30 minutes. The 1: 1 copper complex, which precipitated out as a green-yellow precipitate, is completely dissolved by adding 2N sodium hydroxide solution to a pH of 9.0 to 9.5. The yellowish green solution is evaporated to dryness, 7 parts of copper complex being obtained in the form of an olive-green, slightly water-soluble powder.

Claims (21)

1. Process for improving the light-fastness of leather dyed with anionic chromium complex or cobalt complex dyes, which process comprises treating the leather, before, during or after dyeing, with a copper compound.

2. Process according to claim 1, wherein the copper compound used is a copper salt of an inorganic or organic acid, optionally in admixture with a further organic carboxylic acid.

3. Process according to claim 2, wherein copper chloride, copper sulfate, copper nitrate, copper acetate, copper tartrate or copper salicylate is used.

4. Process according to claim 2, wherein there is used copper chloride, copper sulfate, copper nitrate or copper acetate in admixture with an organic hydroxycarboxylic acid, particularly tartaric acid or salicylic acid.

5. Process according to claim 1, wherein the leather is treated with a copper complex of bisazomethines, acylhydrazones, semicarbazones or thiosemicarbazones of aromatic aldehydes or ketones, which complex can optionally contain sulfo groups.

6. Process according to claim 5, wherein there is used, for improving the light-fastness, a bisazomethine metal complex of the formula II

in which R, is hydrogen or an unsubstituted or substituted alkyl or aryl radical, Y is an unsubstituted or substituted alkylene or arylene radical and Me is copper, n is 1 to 3 and the benzene radicals A and B are unsubstituted or further substituted by C₁-C₄alkyl, C₁-C₄alkoxy, halogen, cyano- or nitro.

7. Process according to claim 5, wherein there is used, for improving the light-fastness, an acylhydrazone metal complex of the formula III

in which R, and Me have the meanings defined under the formula II, R₂ is hydrogen or an unsubstituted or substituted alkyl or aryl radical, Q is oxygen or NH, and n is zero or 1.

8. Process according to claim 5, wherein there is used, for improving the light-fastness, a complex of the formula IV

in which R₁ and Me have the meanings defined under the formula II, and X is oxygen or sulfur.

9. Process according to claim 5, wherein there is used, for improving the light-fastness, a complex of copper of compounds of the formula V

in which R₃ is hydrogen, OH, alkyl or cycloalkyl, and in which the ring A can be unsubstituted or further substituted by sulfo, sulfonamido, methyl, methoxy or chlorine.

10. Process according to claim 5, wherein there is used, for improving the light-fastness, a complex of the formula VI

in which R₄ is C₁-C₁₈alkyl or cycloalkyl, and the rings A and B can be substituted by C_l-C₄alkyl, cycloalkyl, C,-C₄alkoxy, halogen or OH, or can also contain further fused-on rings, or can be replaced by heterocyclic rings.

11. Process according to any one of claims 1 to 10, wherein the metal compound for improving the light-fastness is used in an amount of 0.1 to 10 % by weight, preferably 0.5 to 5 % by weight, relative to the weight of the leather.

12. Process according to any one of claims 1 to 11, wherein the leather after dyeing is treated with a salt of copper for improving the lightfastness.

13. Process according to claim 1, wherein the anionic dye used is a chromium- or cobalt-containing or mono-, di- or polyazo, azomethine, formazan, anthraquinone, xanthene, nitro, triphenylmethane, naphthoquinoneimine or phthalocyanine dye.

14. Process according to claim 13, wherein a 1 : 2 cobalt or 1 : 2 chromium complex of an azo or azomethine dye is used.

15. Process according to claim 14, wherein there is used a dye of the formula VII

in which

Z independently of one another are nitrogen or a CH group,

A and C independently of one another are each a radical of the benzene or naphthalene series, which radical contains in the o-position with respect to the azo or azomethine group a hydroxyl or carboxyl group,

B and D independently of one another are each the radical of a coupling component when Z is nitrogen, the coupling component containing the group X in the o- or α-position with respect to the azo group, or independently of one another are the radical of an o-hydroxyaldehyde when Z is the CH group,

X₁ independently of one another are each oxygen or a group of the formula ―NR₅―, in which R₅ is hydrogen or a C,-C₄alkyl group,

Me, is chromium or cobalt,

Y is the S0₃H, COOH, P0₃H₂ or S0₂-V group, in which V is C_l-C₄alkyl, unsubstituted or substituted by halogen, vinyl, amino, N-mono- or N, N-dialkylamino,

p is 1 or 2, and

m is an integer from 0 to 6.

16. Process according to claim 15, wherein there is used a dye of the formula VIII

in which

Z independently of one another are a CH group or preferably nitrogen,

A' and C' are each the radical of a 1-hydroxy-2-aminobenzene which carries a nitro group in the 4- or 5-position, or the radical of a 1-hydroxy-2-aminobenzene, which carries a nitro group in the 4-position and a sulfo group in the 6-position, or the radical of a 1-hydroxy-2-aminobenzene which carries a nitro group in the 6-position and a sulfo group in the 4-position,

B' and D' independently of one another are each the radical of one of the following coupling components, when Z is nitrogen : 1- or 2-naphthol which is unsubstituted or substituted by a sulfo group, m-phenylenediamine, resorcinol, p-alkyl(C₁-C₆)phenol 1-phenyl-3-methyl-5-pyrazolone or acetoacetic acid anilide, where the phenyl group in the two last-mentioned compounds can be substituted by C_l-C₄alkyl C₁-C₄alkoxy, chlorine or sulfo, or when Z is the CH group, the radical of an o-hydroxybenzaldehyde or o-hydroxynaphthaldehyde, which can each be substituted by phenylazo or sulfophenylazo,

Me, is cobalt or chromium, and.

Ka^⊕ is a cation.

17. Process according to claim 14, wherein there is used one of the dyes of the following formulae :

in which q is an integer from 0 to 2, Me, is cobalt or chromium, Ka^⊕ is a cation and Y is methyl, ―CONH₂ or -CO-NHR, in which R is an alkyl group having 1 to 4 C atoms ; or of the formula X

in which X₂ is hydrogen, chlorine, methyl or methoxy, Me, is cobalt or chromium, and Ka^⊕ is a cation ; or of the formula XI

in which q is an integer from 0 to 2, and Ka^⊕ is a cation ; or of the formula XII

in which

A₁ is the radical of 1-hydroxynaphthalene or 2-hydroxynaphthalene,

R₆ is hydrogen, chlorine or methyl,

R₇ is hydrogen nitro or chlorine, and

Ka^⊕ is a cation, and of the substituents X₃, X₄ and X₅ one is an S0₃ group and the two others are hydrogen, X₅ being hydrogen when R₆ is chlorine and R₇ is hydrogen ; or of the formula XIII

in which X₆ is hydrogen, chlorine or nitro, and Ka^⊕ is a cation, and in which the sulfo group in the pyrazolone dye in the ring A or B and the nitro group in the ring A of this dye are arranged in the 4-, 5- or 6- positions of the 1-hydroxy-2-aminobenzene ; or of the formula XIV

in which X₆ is hydrogen, chlorine or nitro, Ka^⊕ is a cation, and A, is the radical of 1-hydroxynaphthalene or 2-hydroxynaphthalene.