A feasible approach for enhancing union dyeing of wool/acrylic blend fabrics with heterobifunctional cationic reactive dyes

In this work, a facile method to enhance union dyeing with cationic reactive dyes on wool/acrylic blend fabrics was reported. Three cationic reactive dyes containing various numbers of reactive groups were synthesized and employed on wool, acrylic and wool/acrylic blend fabrics using the one-bath one-step method. Factors affecting the dye exhaustion, union dyeing and leveling properties, including dyeing pH, temperature and dye structure, were investigated. Experimental results revealed that the cationic reactive dye containing heterobifunctional reactive groups and a cationic group attached on the backbone of structure exhibited better union dyeing properties, irrespective of dyeing method. The improvement in the union dyeing on wool and acrylic fabrics followed a decreasing order: Dye 1 > Dye 3 > Dye 2. In additional, the wool/acrylic blend fabrics dyed with Dye 1 showed outstanding leveling properties. The fastness properties of wool/acrylic fabrics for all cationic reactive dyes were good to excellent.