Dyeing of nylon with reactive dyes. Part 2. The effect of changes in level of dye sulphonation on the dyeing of nylon with reactive dyes

Four mono-functional reactive monochlorotriazinyl (MCT) dyes, each derived from the same chromophore and possessing a single monochlorotriazinyl reactive group, but differing only in degree of sulphonation, were synthesised and evaluated on nylon. The colour yield, degree of exhaustion, fixation, and the fastness properties of each dye were assessed. Initial exhaustion, at pH 4, was high for all dyes but percentage fixation, via covalent bond formation, increased with increasing levels of sulphonation. In all cases fixation efficiency reduced markedly with increasing concentrations of dye applied.