Design, synthesis, characterization of water-soluble indophenine dyes and their application for dyeing of wool, silk and nylon fabrics

Abstract

In view of our continuing interests in application of quinoidal heterocyclic structure into textile dyestuffs, we report here the design and synthesis of four new water-soluble dyes D1-D4 that based on indophenine structure and bearing alkyl chains with different lengths. Their properties on geometry, electronic structure, solubility, thermal stability and absorption spectra have been well investigated. Then, the dyeing ability of D1-D4 is checked by application into dyeing of wool, silk and nylon fabrics and is compared with three commercial acid dyes. The effect of quinoidal coplanarity of indophenine backbone and alkyl substituents on dyeing performance has been revealed. Our study clearly demonstrates that the introduction of rigid quinoidal heterocyclic structure with high coplanarity as the chromophore backbone is an efficient method for the design of high-performance acid dyestuffs in terms of exhaustion, coloring strength and wet fastness.