Cationisation of Cotton with Natural Source Based Gelatin for Salt-Free Reactive Dyeing of Cationised Cotton

Cotton fabric was chemically modified with gelatin, extracted from fleshing waste of collagen by thermal hydrolysis process to increase the dyeing capability of reactive dye. Gelatin imparts new functional groups with fabric and develops Ammonia ion in slightly acid conditions to obtain cationized cotton fabric permit salt and alkali-free reactive dyeing with acceptable shade depth. The imparting of gelatin on the cotton fabric was confirmed by FTIR, UV/VIS absorption, and K/S values. The result shows that they have advantage of high dye utilization and better fastness. Color fastness of treated dyed fabric was equal to the untreated dyed fabric and obtained 4/5 washing fastness, 5 rubbing fastnesses, and 4/5 perspiration fastness. The UV/VIS absorption results show 6.4% improvement in exhaustion and K/S results have 7% improvement in fixation and 9.4% in dye utilization to that of untreated dyeing with salt. Cationized fabric not only increased the exhaustion of the dye but also improved the crease resistance angle at 120° due to the formation of cross-linkage between amide group and the carboxylic acid. To obtain the expected results, cationization was done at alkaline media and the optimum parameter was determined, whereas dyeing conducted at slightly acidic media with optimum parameters.