GB660056A - Process for the preparation of disazo acid dyestuffs - Google Patents

Abstract

Acid disazo dyestuffs are obtained by coupling in acid solution diazotized aminoazo dyestuffs of the formula <FORM:0660056/IV (c)/1> with 2-amino-8-naphthol-6-sulphonic acid or an N-alkyl or N-aryl derivative thereof; in the formula, Y is hydrogen, alkyl or halogen and X is -O-aryl, -O-aralkyl, <FORM:0660056/IV (c)/2> <FORM:0660056/IV (c)/3> an alkyl group of at least 5 carbon atoms. The products dye wool and silk in violet, blue or black shades. The monoazo dyestuffs of the above formula are obtained by diazotizing an amine <FORM:0660056/IV (c)/4> coupling the product with a 1-amino-3-aryl-sulphonylamino-benzene-6-sulphonic acid and treating the coupling product with an alkylating agent. Examples show the use of the following components: (1) amines of the second formula above: 2-amino-4-chlorodiphenyl ether, p-tert. amyl-aniline, p-aminodiphenyl ether, 2-benzyloxy-5-chloraniline, N-benzyl - N - (p - aminophenyl) - toluene p-sulphonamide, N - methyl - N - (31 - chloro - 41-aminophenyl) - toluene p - sulphonamide, N-ethyl - N - phenyl - 4 - amino - toluene - o-sulphonamide, N - benzyl - N - phenyl - 4-chloro - 3 - amino - benzenesulphonamide and N - benzyl - N - cyclohexyl - 2 - amino - benzene-sulphonamide; (2) middle components: 1-amino - 3 - arylsulphonylamino - benzene - 6-sulphonic acids where the aryl group is phenyl and p-tolyl, N-alkylated by treatment with dimethyl and diethyl sulphates; (3) end components: 2-amino-, 2-methylamino- and 2-o-tolylamino-8-naphthol-6-sulphonic acids. Samples have been furnished under Sect. 2 (5) of further dyestuffs prepared by the above process, derived from the following components (apart from those specified above): (1) amines of the second general formula: 2-amino-4-chloro - 41 - cyclohexyl - diphenyl ether, 2-benzyloxy - 5 - tert. - amyl - aniline, 2 - amino-21 - methyl - diphenyl ether, N - ethyl - N-phenyl - 2 - amino - benzene - sulphonamide, N - methyl - N - (ar - tetrahydro - 1 - naphthyl) 2 - amino - benzenesulphonamide, N - benzyl-N - phenyl - 2 - amino - benzenesulphonamide, N - ethyl - N - phenyl - 3 - amino - 4 - chlorobenzenesulphonamide, N - ethyl - N - phenyl6 - amino - toluene - m - sulphonamide and N-benzyl - N - cyclohexyl - 4 - amino - toluene - o - sulphonamide; (2) middle components: 1-amino - 3 - (N - methyl - o - toluenesulphonamido)- and 1-amino-3-(N-methyl-p-chlorobenzenesulphonamido) - benzene - 6 - sulphonic acids; (3) end components: 2-p-tolylamino-and 2 - mesidylamino - 8 - naphthol - 6 - sulphonic acids.