Study on reactive dyeing in a sustainable nonaqueous medium dyeing system by X-ray electron spectroscopy

In the nonaqueous medium dyeing system (decamethylcyclopenta siloxane; D5), the bonding between cotton fiber and reactive dye may be influenced by the dyeing medium. To evaluate the dyeing performance of reactive dye in the D5 dyeing system, the fixing of reactive dyes with different structures was studied. Before and after dyeing, the chemical environment of cotton fiber was investigated by X-ray electron spectroscopy, and compared with the spectroscopic method. Compared with traditional reactive dyeing, the color depth of the dyed cotton fabrics and the final fixation of dyes are much higher in the D5 dyeing system. The elements of the cellulose fiber surface are changed after dyeing. Especially for N element, its content is increased after dyeing. After 30 minutes, the final fixation of reactive dye is about 80% by analyzing the account of N. Compared with the undyed cellulose fiber, the peak area of C–C or C–H is gradually increased after dyeing, but the proportion of C–O is decreased with the fixing time. The proportion of O–C–O is not changed much with the fixation time. Therefore, the C–C or C–H chemical environment on the cellulose fiber surface will be changed after dyeing. Therefore, the bonding of dyes and fibers can be analyzed through the change of the C1s chemical environment or the amount of N element before and after dyeing. This investigation successfully developed a method which could evaluate the fixation process in the D5 dyeing system.