GB430614A - Process for the manufacture of azodyestuffs insoluble in water - Google Patents

Abstract

Azo dyes; azo dyes, forming upon the material.--Azo dyes insoluble in water are manufactured in substance or on the fibre by diazotizing aromatic bases of the general formula <FORM:0430614/IV/1> where R and R1 are aryl, alkyl or aralkyl radicles and X1 and X2 are hydrogen atoms or aryl, alkyl or aralkyl radicles, and coupling with the arylides of b -hydroxynaphthoic acid. In examples, cotton yarn is impregnated with the 4 - chloro - o - anisidide, a - and b - naphthylamides of 2 : 3-hydroxynaphthoic acid and developed with diazotized 1-methoxy-2-benzoylamino - 4 - diethylsulphonamido - 5 - aminobenzene, yielding Bordeaux, garnet, and corinth shades respectively. Specifications 6379/12, [Class 2 (iii)], 17279/13, 279,146, and 303,838, [all in Class 15 (ii)], are referred to. The bases employed as diazo components above are manufactured by subjecting a compound of the general formula <FORM:0430614/IV/2> to nitration in an organic solvent and reducing the resulting nitro-compounds. In an example, 1 - methoxy - 2 - benzoylamino - 4 - diethylsulphamidobenzene (obtained by the action of diethylamine on the corresponding sulphochloride) is nitrated in chlorobenzene solution and the product is reduced by iron and acetic acid. The Specification as open to inspection under Sect. 91 comprises in general the use of any coupling components having an affinity for cotton, the following being additionally specified: the arylides of hydroxyanthracenecarboxylic acids and of hydroxycarbazolecarboxylic acids and the diacetoacetyl derivatives of p-diamines of the diphenyl series. This subject-matter does not appear in the Specification as accepted.