Synthesis and application of highly substantive reactive dyes

Abstract

A novel highly substantive reactive dye based on anthraquinone chromophore was prepared. The synthesis of this dye was achieved by the modification of free amino group containing anthraquinore by, firstly, reacting with cyanuric chloride and followed by N-(2-aminoethyl) pyridiniumchloride hydrochloride. TLC technique was employed to follow the chemical reactions. The application of the prepared dye into cellulosic fabric was carried out using exhaustion dyeing process in the absence of electrolytes. The results showed that, despite no electrolyte present in the dyebath, high percentage of dye echaustion could be obtainable. The high percentage of dye exhaustion was attributed to the attractive force between positive charge on the dye molecule and negatively charged fiber surface. The high degree of total dye fixation comparable to the low salt reactive dye available in the market was also achievable. The wash fastness of dyeing was excellent. Surprisingly, it was found that this type of cationic group containing reactive dye showed markedly improved light fastness properties which could not be achieved in the case of traditional cationic dyes. It was believed that the cationic group was loosely attached to the chormophore which was later eliminated during washing-off process.