A new way to improve the light-fastness of azo reactive dyes through the introduction of benzene sulfonamide derivatives into the triazine ring

Herein, a new kind of hetero-bifunctional reactive dyes with high light-fastness was designed and synthesized by introducing benzene sulfonamide and its derivatives into the triazine ring. Benzene sulfonamide or its derivatives and 2-amino-5-naphthol-7-sulfonic acid (J-acid) were condensed with cyanuric chloride to synthesize coupling components, which were then coupled with the diazo salt of 4-(β-sulfatoethylsulfonyl)aniline. The dyes were characterized by IR spectroscopy and MS. The color fastness test proved that the light-fastness of the dyes could be improved by 1 grade via the introduction of benzene sulfonamide derivatives into the triazine ring when compared with the case of the control dyes. Fluorescence spectra demonstrated that after the introduction of benzene sulfonamide derivatives, the dye molecule could return to the ground state from the excited state and emit fluorescence; in addition, the introduced benzene sulfonamide derivatives helped to deteriorate the adverse effect of UV light on the dye. Moreover, the dyeing results showed that the dyes containing the sulfonamide groups had equal dyeing properties when compared with that of the control dyes.