Laccase-Catalyzed Dyeing and Finishing of Textiles with Gallic Acid

Abstract

Laccase from Rhus vernicifera was applied to catalyze the polymerization of gallic acid (GA) as a way of “in situ” dyeing and finishing for wool, silk, nylon, cotton and viscose fabrics. The laccase-catalyzed polymerization of GA was confirmed by the results of UV-vis spectroscopy and differential thermal analysis. The adsorption of the GA oxidation product on the fibers contributed to the color effect and functional performance of treated fabrics. The dyed fabrics exhibited gray colors with pale to medium shades, depending on fiber categories. All the dyed fabrics showed significantly enhanced UV protection performance and antioxidant activity, and the dyed wool and silk had obviously improved deodorizing ability. These improved functional properties were related to the increased quantity of aromatic rings, phenolic hydroxyl groups and carboxyl groups in the GA oxidation product adsorbed by fibers.