New Laccase-Mediated System Utilized for Bio-Discoloration of Indigo-Dyed Denim Fabrics

In this study, indigo-dyed denim fabric was decolorized via separate and simultaneous applying of laccase, sodium hydrosulfite, and cellulase. In this regard, the surface reflectance and color coordinates of the discolored fabrics were evaluated and scanning electron microscopy (SEM) images of the cellulase treated fabric were prepared to analyze their surfaces. Finally, the characterization of the treated samples was investigated, including moisture content, crease recovery angle, air permeability, and abrasion resistance. The color experiments showed that simultaneous applying of laccase, sodium hydrosulfite, and cellulose had a 55.79% improvement in the samples' lightness (L*). Furthermore, the color coordinate test of specimens revealed that the hue of the treated samples was changed to blue and green, and the purity of color (C*) was modified. The increment in the moisture content and air permeability of the treated specimens indicated that the comfort of the jeans clothing had been enhanced. As a result, sodium hydrosulfite demonstrates a high-efficiency denim discoloration in the laccase-mediated system.