GB454729A - A process for dyeing animal fibres - Google Patents

Abstract

Azo dyes forming on the material.--Animal fibres such as wool or silk, with or without an admixture of filling agents such as cotton or artificial silk, are dyed by subjecting them to the action of a bath containing an aqueous solution of a diazotized amine and one or more compounds or salts of chromium, copper, nickel or cobalt, and thereafter rinsing in water and drying. The following examples are specified: (1) Pure silk yarn, well wetted out, is introduced into an aqueous bath containing neutralized diazotized 2-methoxy-4-nitraniline, "Gardinol" (Registered Trade Mark) E conc. powder, soda ash and copper sulphate and worked cold for 5--10 minutes, whereupon the bath is slowly brought to the boil and so maintained for \ba1/2\be hour; the yarn is then rinsed and dried to obtain a brownish maroon dyeing; (2) Pure silk yarn, well wetted out, is introduced into an aqueous bath containing neutralized diazotized 1-naphthylamine, "Gardinol" as in (1) and sodium bichromate and worked cold for 5--10 minutes, whereupon the bath is slowly heated to 80--90 DEG C., sulphuric acid is added and the temperature is maintained for \ba1/2\be hour at or near the boil; the yarn is then rinsed and dried to obtain a brown dyeing; (3) Wool yarn, well wetted out, is introduced into an aqueous bath containing neutralized diazotized 2-methoxy-4-nitraniline, "Gardinol" as in (1) and soda ash and worked cold for 10 minutes, whereupon copper sulphate is added, the bath is slowly brought to the boil and so maintained for \ba1/2\be hour; the yarn is then rinsed and dried to obtain a brown dyeing.