Abstract

A novel polymeric dye was constructed by the reaction of hydroxyl-terminated hyperbranched poly (amine-ester) (HPAE) with a reactive dye. Firstly, the 2nd generation of HPAE (HPAE-2) was modified with different amounts of maleic anhydride, and then reacted successively with Reactive Light Yellow K-4G (C.I.13245,CAS:12226-48-1) to obtain a new kind of polymeric dye, identified as HPD-1, HPD- 2 and HPD-3, respectively. The structure of HPD-2 was measured by FTIR, which showed that the dye molecule was grafted successfully on HPAE-2. The grafting rates of K-4G were all above 87%. The stabilities of HPD against AlCl3 were investigated by UV-vis spectrum, and it was shown that the polymeric dye was precipitated against Al(III) ions – fixation was likely to be improved if Al3+ was used at the end of dyeing. The polymeric dyes were used in the colouration of wet-blue leather, and their exhaustion rates were more than 99%. Leather samples dyed with HPD had good colour saturation and levelness proved by colour differences (DE). Dry and wet rubbing fastness of the leather samples were grades 4~5, and good washing fastness resulted.