GB741578A - Metalliferous trisazo-dyestuffs and process for making them - Google Patents

Abstract

The invention comprises copper and nickel derivatives of trisazo dyestuffs of the type R1-N=N-R2-N=-R3-N=N-R4, where R1 is the residue of an initial component free from hydroxyl groups, R2 is a benzene or naphthalene residue attached in 1 : 4 positions, R3 is a 1 : 4-benzene residue and R4 is either a sulphonated naphthalene residue free from amino groups or a 5-pyrazolone residue; the metal atom is attached by oxygen atoms to the residues R3 and R4 in positions vicinal to the azo linkage. Preferred compounds contain 3-6 (desirably 3-4), sulphonic acid groups. They are made by coupling diazotised R1NH2 with a p-coupling aniline or naphthylamine, rediazotising and coupling with a p-coupling aniline containing an alkoxyl group ortho to the amino group, diazotising again and coupling with an o-coupling naphthol-sulphonic acid free from amino groups or with a 5-pyrazolone. The middle components are preferably coupled in the form of their methanesulphonic acid derivatives. The final coupling may be accelerated by the addition of alcohol or pyridine. The trisazo dyestuff may or may not be isolated before metallization. Metallization is effected under conditions such that the alkoxyl group in R3 is hydrolysed. There may be used nickel, cuprous or cupric salts or complex metal compounds such as those with ammonia, alkylamines or heterocyclic bases. There may be added an excess of such base or ethanolamine. The metallized dyestuffs give grey tints by dyeing and printing on wool, leather, linen, cotton and regenerated cellulose. Examples show the preparation of the following dyestuffs:-(1) 2-napthylamine-4 : 5- disulphonic acid --> 1-naphthylamine-7-sulphonic acid -X cresidine --> (pyridine) 1-naphthol-4-sulphonic acid, coppered; (2) the aminodisazo intermediate of (1) --> (pyridine) 1-naphthol -4 : 8- disulphonic acid, coppered; (3) 2-naphthylamino-4 : 8-disulphonic acid - X 1-naphthylamine --> cresidine --> (pyridine) 1-naphthol -4 : 8-disulphonic acid --> 1-naphthylamine --> cresidine --> (pyridine) 1-naphthol -4 : 8-disulphonic disulphonic acid, coppered; (5) 2-naphthylamine -4 : 8- disulphonic acid --> 1-naphthylamine-7-sulphonic acid -X 2 : 5-dimethoxyaniline --> (pyridine) 1-naph-4- sulphonic acid, coppered; (6) sulphanilic acid -X 1-naphthylamine -7- sulphonic acid -X cresidine --> (pyridine) 1-naphthol-4-sulphonic acid; coppered. A table is given of further dyestuffs, using as components (other than those mentioned above):-R1NH2: naphthionic acid, 2-(p-aminophenyl) -6- methylbenzimidazole sulphonic acid and N1-acetyl-benzidine-2-sulphonic acid; R2 residue: aniline, m-toluidine; R3 residue: o-anisidine; R4 residue: 1-naphthol-5-sulphonic acid and chromotropic acid. A further example is given of the dyeing of cotton with the product of (1). Other suitable components are listed. Specification 644,883 is referred to.