Effects of repeated domestic launderings and non-durable press on the colour properties of plain woven cotton fabrics

Abstract

The colour values and colour differences occurred in dyed cotton fabrics after repeated domestic launderings and non-durable pressings (hot-pressings) have been assessed. Two reactive dyes with different chemical structures (monochlorotriazine and vinylsulphone) were applied to the cotton fabric separately at different dyeing concentrations and the domestic ironing was simulated by using international hot-pressing standards. The K/S value, lightness (L*), chroma (C*) and colour differences (DE*) were measured for the repeated experiment cycles. It is observed that the K/S values decrease and L* values gradually increase indicating the loss of some dye from the fibres and decreasing depth. C* values change in different ways for the two dye classes because of the different fixing and colouring properties of the two dyes. Colour differences are found to depend on the chemical class and concentration of the reactive dyes used, and colour measurement time. Dyeing at low dye concentrations is affected more from the repeated experimental procedure.