GB857386A - Azo dyestuffs and metal complexes thereof - Google Patents

Abstract

The invention comprises dyes of formula: <FORM:0857386/IV (c)/1> where X is a carbon-to-carbon bond, an oxygen or sulphur atom or an azo bridge, R1 is an arylene residue of the benzene or naphthalene series, R11 is H, Me or Et and Y is OH or an amino or substituted amino group, A may carry halogen atoms or alkyl, alkoxy, aryl or acylamino groups and B and R1 may be further substituted. The invention also includes metal complexes of the above dyes, preferred being chromium, cobalt and copper complexes. The dyes are made in conventional fashion from appropriate diazotised nitranilines and azo components, coupling being effected in an alkaline medium, with subsequent metallisation if desired. Dyes in which R11 is Me or Et may easily be converted into #s, #s1- dihydroxy dyes by treatment with aqueous alkali metal hydroxides. Metallisation may be effected in substance, or on a substrate, optionally in the presence of other metallisable dyes. Representative of specified coupling components are 4- hydroxydiphenyl -41- sulphonic acid and its amide and b - hydroxyethylamide, 4-hydroxy -41- amino- and -acetylamino-diphenyl-31- sulphonic acids, 4- hydroxydiphenylether -41-sulphonamide, 4- hydroxydiphenylsulphide -41-sulphonic acid, 4- hydroxy -3- methylazobenzene -21- sulphonic acid, 4- hydroxy -3-phenylazo- (1, 11)- benzene -31- sulphonic acid and p 4- hydroxybenzeneazo- (1, 11)- naphthalnee-51- sulphonic acid. Representative of specified diazo components are 1- amino -2- hydroxy-, 2-methoxy- and 2- hydroxy -3- chloro -5- nitrobenzenes, 1- amino -2- hydroxy -3, 5- dinitrobenzene and 1- amino -2- hydroxy -5- nitrobenzene -3- sulphonic acid. The metal-free dyes dye wool or wool-like materials by the single bath or after-chroming process. Sulphonic acid group free dyes metallised in substance, preferably chromed or cobalted, advantageously to give 1, 2- complexes may be used to dye wool, silk, leather and polyamide materials from neutral to weakly acid baths. Examples are provided of the preparation of the dyes and their metal complexes and the use of the dyes and complexes in dyeing processes brown and green shades being obtained. Specifications 637,404 and 758,016 are referred to.