Eco-Friendly Pretreatment to the Coloration Enhancement of Reactive Dye Digital Inkjet Printing on Wool Fabrics

Digital inkjet printing on high-class wool textiles is in line with the trend, but the challenge such as reducing the impact of wool scales on print quality is still worth of attention. In this study, a novel environment-friendly method was applied to wool inkjet printing pretreatment without any generation of hazardous substances. H2O2 and papain were adopted to pretreat wool fabric before the inkjet printing process. Both the wettability and zeta potential of the treated fabric were improved obviously. Moreover, Fourier-transform infrared spectroscopy spectra and Xray photoelectron spectroscopy spectra proved the synergistic effect of H2O2 and papain where the oxidation of wool by H2O2 provided more sites for papain to hydrolyze wool peptide. The synergistic pretreatment produces additional sites for reactive dye fixation. As a result, the treated wool obtained higher color strength which greatly exceeds that of the untreated wool, and there is no discharge of harmful substances during the whole process. This work provided a promising direction for decreasing the discharge of harmful substances and improving the utilization rate of dye solution to achieve cleaner production.