Colour matching of cotton exhaustion dyed using reactive dye mixtures in non‐aqueous siloxane media of D5

Abstract A less water dyeing system using non‐aqueous medium as dyeing medium shows promising application potential due to its environmentally friendly and efficient dyeing processes, achieving high dyeing and fixation percentage of 100% and 90%, respectively. While previous studies have focused on the dyeing procedures and mechanisms of cotton dyeing in non‐aqueous medium, there has been limited research on colour matching between reactive dyes. This study investigates the matching performance of the representative dyes C.I. Reactive Red 195 and C.I. Reactive Blue 19 in a novel non‐aqueous dyeing system, and compares their effectiveness to that of traditional aqueous dyeing systems. The building up power of reactive dyes in different dyeing bath was studied, as well as the influence of compounding ratio and fixing temperature on dyeing performance. The results reveal that reactive dyes exhibit better building up properties in non‐aqueous medium compared to traditional water bath. The colour change and matching of the reactive dyes was different between non‐aqueous medium and water bath, showing noticeable variations in fixation percentage. Notably, when the ratio between Reactive Red 195 and Reactive Blue 19 was 1:1, the absorption wavelength of the blend dye in the non‐aqueous medium remained stable with increasing fixation temperature, while a redshift occurred in the water bath. Overall, the colour matching performance of reactive dyes in the less water dyeing system using a non‐aqueous medium is impressive, suggesting significant potential for further development in sustainable dyeing technology.