The use of sodium edate in dyeing: II. Union dyeing of cotton/wool blend with hetero bi-functional reactive dyes

Union dyeing of cotton/wool blend with hetero bi-functional reactive dyes, namely CI Reactive Yellow 145, CI Reactive Red 194, and CI Reactive Red 195 is obtained using one-bath and two-bath dyeing processes. The results obtained are compared with those obtained by conventional two-bath dyeing process. Factors affecting the dyeability, such as the amount of sodium edate, sodium sulphate, temperature and dye concentration are investigated. The dyed fabrics were evaluated with respect to the dye exhaustion and fixation, levelling and the fastness properties. Excellent to good fastness was obtained for all samples irrespective of the dyeing method. The result of investigation offers a new viable method for union dyeing by using sodium edate two-bath and one-bath processes with a better levelling and dye uptake.