Synthesis and application of hetaryl disazo disperse dyes derived from 4-amino-2-chloro-6,7-dimethoxyquinazoline and 3-chloroaniline on polyester fabric

Abstract

In an attempt to find more environmentally friendly azo dyes, the synthesis and application of disazo disperse dye derivatives of 4-amino-2-chloro-6,7-dimethoxyquinazoline and 3-chloroaniline on polyester fabric are reported. The disazo dyes were synthesized via diazotisation of 3- chloroaniline and coupled with 4-amino- 2-chloro-6,7-dimethoxyquinazoline to afford an intermediate azo dye. This intermediate was further diazotised in concentrated sulphuric acid and followed by coupling reactions with various coupling components such as 1,3-diyhydroxybenzene, 2-amino-6-methylbenzonitrile, 3-amino-5-methyl-prazole, 1-napthol and 7-methoxy- 2-naphthol to give the disazo disperse dyes. The basic fastness properties (light fastness wash fastness heat and rubbing fastness) of the dyes on polyester fibre were discussed in terms of their chemical structures. All the synthesized disazo disperse dyes were characterized on the basis of their spectral analyses, IR, ¹H NMR, ¹³C NMR and UV-visible spectroscopic data. The light fastness results were observed to be good ratings (5) and very good ratings (5/6). The sublimation test results gave excellent ratings of (5). Also, it was found that the wash fastness property, which is an indicator whether a dye could have affinity for a textile fabric or not, have excellent ratings of 5. From these results, it can be concluded that the best of these disazo dye compounds could be commercially important in the textile industry.

Keywords: Disazo dyes, disperse dyes, hetaryl compounds, fastness, polyester fib, quinazoline.