Environment-Friendly High-Efficiency Continuous Pad Dyeing of Non-Shrinkable Wool Fabric by the Silicon Fixation Method without Auxiliary Chemicals
Yuni Luo, Shixiong Zhai, Liujun Pei, Jiping Wang, Zaisheng Cai
Abstract
Conventional pad dyeing methods rely on auxiliary chemicals and consume high energy and a large amount of water to achieve continuous or semicontinuous pad dyeing. Here, a new continuous pad dyeing method was developed by using decamethylcyclopentasiloxane (D5) as the fixation medium; non-shrinkable wool fabric obtained an incredible fixation rate of up to 99% without auxiliary chemicals in the dyeing process. In this work, the optimal temperature and time of the D5-fixation process was 100 °C for 1 min. Compared with conventional dyed samples, non-shrinkable wool fabric with D5-fixation exhibited a better dye penetrability and higher color-fastness, color strength, and area shrink. Furthermore, the results of XRD, FT-IR spectroscopy, and SEM analyses indicated that D5 has no influence on the surface structure, micro-structures, and color properties of wool fabrics. Also, the wool fabrics exhibited good color properties with reused D5. This new continuous rapid pad dyeing method shows a lower commercial level with reduced consumption and nearly half of the wastewater compared with conventional pad dyeing methods, which has a considerable potential to promote the development of a sustainable continuous pad dyeing technology. D5-fixation has the potential to replace the cold pad-batch and steam fixation and would substantially reduce the environmental footprint and achieve real continuous pad dyeing in the conventional dyeing process.