GB570972A - Disazo dyestuffs - Google Patents

Abstract

Disazo dyes are made by coupling, in acid medium, a diazotised primary arylamine of the benzene or naphthalene series carrying at least one sulphonic acid or aminosulphonyl group, wherein hydrocarbon residues or substituted hydrocarbon residues may replace the hydroxy of the sulphonic acid and the hydrogen of the aminosulphonyl group, and which may be further substituted by groups other than nitro or acidylamino groups, with 1-amino-8-naphthol-3.6- or 4.6-disulphonic acid, and coupling, in alkaline medium, to the resulting monoazo compound a diazotised arylamine of the general formula X-CO-NY-R-NH2, where R represents a p-phenylene residue which may be substituted by, e.g. methyl or methoxy, but which contains no aryloxy or sulphonic acid substituent, X represents a monochloro- or monobromo-methyl group and Y represents an alkyl group of less than 7 carbon atoms or a cycloalkyl residue. The products dye animal fibres, wool and silk being specified. In examples, the following dyes are prepared: 1 - chloro - 2 - aminobenzene - 4 - sulphonanilide or sulphon - N - ethylanilide --> (acid) H - acid (alkaline) \Ms 4 - amino - 1 - N - cyclohexyl-o -chloroacetanilide, 3- or 4 - aminobenzenesulphonic acid --> (acid) H-acid (alkaline) \Ms 4 - amino - 1 - N - cyclohexyl-o -chloroacetanilide, 4 - aminobenzenesulphonamide --> (acid) H - acid (alkaline) \Ms 4 - amino - 1 - N - ethyl-o -chloro- or bromo-acetanilide or 4-amino-1-N-n-butyl - o - chloroacetanilide and 4 - amino - 1 - methylbenzene - 2 - sulphonanilide --> (acid) K - acid (alkaline) \Ms 4 - amino - 1 - N - ethyl-o -chloroacetanilide. Additional components specified are 2 - chloroaniline - 5 - sulphonic acid, 3 - aminobenzenesulphonamide, 3- or 4 - amino - benzenesulphanilide, 3 - aminobenzenesulphon - N-ethyl- or b -hydroxyethyl-anilide, 1-chloro-4-aminobenzene - 2 - sulphonanilide, 1 - chloro - 4 - aminobenzene - 2 - sulphon - N - ethyl - anilide, 4 - amino - 1 - methylbenzene - 2 - sulphon - N - ethylanilide, 1 - aminonaphthalene - 7 - sulphonanilide, 4-aminophenylmethyl sulphone and 1-aminobenzene-2.4-dimethyl sulphone; 4-amino-1-N-isopropyl- or (p-methylcyclohexyl)-o -chloroacetanilide and 5 - amino - 2 - N - cyclohexyl-o -chloroacet-toluidide. Specification 391,626 is referred to. The Provisional Specification describes also dyestuffs of the above type, wherein (a) the diazo compound coupled in acid medium is not restricted as regards the optional substituents; (b) the coupling component is any 1-amino-8-naphthosulphonic acid having the 2- and 7-positions free, and (c) R, in the above general formula, also represents a m-phenylene residue and may also carry sulphonic groups, except para to the amino group, X represents a monochloro- or monobromo-alkyl radical having not more than three carbon atoms and Y also represents hydrogen, aralkyl, alkoxyalkyl or aryl.