2.1. Materials

Food-grade colorless tea polyphenols were purchased from Liyuan Food Additives Limited Company of Guangzhou in Guangdong Province of China, which were treated by decolorization processing, and the content of effective substance was 99%.

The wool fabric (warp density 86 yarns per inch, weft density 51 yarns per inch; weight 132.0 g/m²) was purchased from Jiangsu Huaxi Spinning Limited Company (Suzhou, China). The silk fabric (warp density 325 yarns per inch, weft density 34 yarns per inch; weight 75.0 g/m²) was bought from FING SILK Limited Company (Hangzhou, China).

Both citric acid and disodium hydrogen phosphate were analytical reagents, and purchased from Tianjin Comio Chemical Reagent Co., Ltd. (Tianjin, China). Laccase (EC1.10.3.2) Denilite II S was bought from Novozymes Corporation (Beijing, China), which was prepared from Aspergillus through utilizing submerged fermentation, and the standard enzyme activity was 120 LAMU/g (LAMU= Laccase Units of Modified Aspergillus).