GB478514A - Process for the manufacture of azodyestuffs - Google Patents

Abstract

Azo dyes are made by coupling a diazotized aromatic amine in acid medium with a p-coupling monamine of the benzene series, in which one hydrogen atom of the amino group is substituted by an alkylene oxide group and the other hydrogen atom of the amino group may be substituted by a hydrocarbon radical, e.g. alkyl, alkenyl, hydroxyalkyl, alkoxyalkyl or aralkyl, the components being selected in such a manner that the molecule contains at most one salt-forming group. They colour cellulose esters, e.g. acetate artificial silk and mixed fabrics containing the same. In examples, the following dyes are described: (1) and (2) p-nitroaniline or o-chloro-p-nitroaniline --> methylphenylamino-1 : 2-propylene oxide (yellowish scarlet and bluish red); (3) p-nitroaniline --> ethyl-m-tolylamino-1 : 2-propylene oxide (bluish red); (4) 6-bromo-2 : 4-dinitroaniline or 2 : 4-dinitroaniline --> (3-methyl - 6 - methoxy) - n - butylamino - 1 : 2-propylene oxide (reddish blue and bluish violet); (5) 4-nitroaniline-2-sulphonic acid --> methylphenylamino - 1 : 2 - propyleneoxide (deep bordeaux when printed on tissue as sodium salt in a paste containing dithiodiglycol and gum solution); (6) aniline-3-sulphonic acid --> methylphenylamino - 1 : 2 - propyleneoxide (yellow from a bath containing ammonium chloride). The following additional components are also specified in a table: 2 : 6-dichloro-4-nitraniline, 6 - ethoxy - 2 - aminobenzothiazole, 5 - nitro - 2 - aminophenylmethyl - sulphone, 4 - methylsulphonyl - 2 - aminophenylmethylsulphone, p-aminobenzoic acid ethyl ester; ethylphenylamino- and n-butyl-m-tolylamino-1 : 2-propylene oxide. Specification 275,622, [Class 2 (iii)], is referred to.