GB434209A - Process for the manufacture of water-insoluble azo-dyestuffs - Google Patents

Abstract

Azo dyes insoluble in water are made in substance, on a substratum or on the fibre by coupling the diazo compound of an amine of the formula <FORM:0434209/IV/1> (in which R=an aryl nucleus free from solubilizing groups, x=CH3, halogen or alkoxy and y=H, CH3, halogen or alkoxy), with a 2 : 3--oxynaphthoic acid arylamide containing in the nucleus of the arylamide residue an alkoxy group and which nucleus may contain further non - solubilizing substituents. Orange to bordeaux shades are obtained fast to boiling in aqueous caustic soda. In examples, the following dyestuffs are prepared in substance or on cotton: (1) 1-amino-2-methoxybenzene-5-sulphonic acid phenylester --> 1-(2<1> : 3<1>-oxynaphthoylamino) - 2 : 4 - dimethoxy - 5 - chloro benzene (clear red); (2) 1-amino-2-methylbenzene-5-sulphonic acid-4<1>-chlorophenylester --> 1 - (2<1> : 3<1> - oxynaphthoyl - amino) - 2-methyl - 4 - methoxybenzene (yellowish red); (3) 1 - amino - 2 : 4 - dimethylbenzene-5-sulphophenylester --> the 2-methyl-4-methoxyanilide (bluish red). Samples have been furnished under Sect. 2 (5) of the following dyestuffs: (1) 5-amino-4-chloro-2-methoxybenzene-1-sulphophenylester --> the 2-methyl-4-methoxyanilide; (2) 5 - amino - 2 : 4 - dichlorobenzene - 1 - sulphophenylester --> the 2 : 5-dimethoxy-4-chloranilide. Specifications 6379/12, 17279/13, 193,834, 193,866, 336,938, [all in Class 2 (iii)], and 343,419 are referred to. Sulphonic acid arylesters of the above formula are made by condensing the corresponding nitroarylsulphonic acid chlorides with the corresponding sodium phenolates and reducing. The esters used in preparing the samples are made from the corresponding acetylamino compounds followed by hydrolysis. 1 - Acetylamino - 2 : 4 - dichloro - 5 - sulphochloride (sample 2) is made from 2 : 4-dichloracetanilide and chlorsulphonic acid.