Synthesis of Direct dyes based on non-carcinogenic amines for leather and textile industry
Syeda Shaista Gillani*, Ehsan Ilahi Qureshi and Munawar Ali Munawar
ABSTRACT: A series of direct dyes based on 4,4'-diaminodiphenylamine-2'-sulphonic acid (1-5) have been synthesized to be used as potential alternative to benzidine ( human carcinogenic) and they are eco-friendly. Benzidine derivatives containing alkoxy groups ortho to an amino group of meta-phenyl diamine removed carcinogenicity. The Benzidine analogue was diazotized and coupled with widely used dye intermediate dye like FC acid to generate a group of direct dyes giving yellow, mustard, blue, purple and greenish black shades on cotton, leather and wool. Dye structures were confirmed by visible absorption spectra, IR spectra, and fastness property. Dye purity was confirmed by TLC using BuOH: EtOH: NH4OH:H2O (3:1:0:5:1) as the fluent. The dyed fabrics showed very good to excellent wash fastness and moderate to good light and perspiration fastness properties.