The effect of polyhydroxyurethane on dyeing of cellulosic fabrics with direct and reactive dyes

Dye yields and fastness properties are reported for direct and reactive dyes using a modified dyeing solution with polyhydroxyurethane. Excellent dye yields and colour fastness properties were obtained without the use of electrolytes, multiple rinsing or fixation agents, which are normally employed in cotton dyeing. From the results, it was found that polyhydroxyurethane media exhibit better dyeability and fastness than the normal aqueous media. Dye adsorption in polyhydroxyurethane media was much higher than in other aqueous systems. The dyed samples showed good hot pressing and washing colour fastness properties within the color change range. The excellent solubility of these dyes in the polyhydroxyurethane aqueous solution makes them ideal for use in exhaustion dyeing.