2001 Volume 44 Issue 2 Pages 95-103
Examination was made of the effects of detergent builders with metal removal capacity on cotton fabrics dyed with direct copper complex dyes, with particular attention to color change and fastness that would result from washing. The dyed fabrics were washed by LAS and a combination of builders (STPP and Zeolite) in distilled and hard water (4, 10, 20° DH), and also by commercial detergent. Color differences and amounts of copper on the dyed fabrics before and after washing were examined and measured. The fastness color scale was established based an equation derived from analysis of CIELAB color differences.
The amounts of copper on premetallized dyed fabrics were found to decrease by washing with the detergent builders, but change in dyed fabric color was only slight. Color change arising from aftertreatment dye showed small color fastness, due to decrease in the amounts of copper on the dyed fabrics. When calcium was present in the washing water, detergent builders appeared to lessen the capacity for removal of copper from dyed fabrics by taking away the calcium ions present in the water prior to deposition on the fabrics.
