Abstract: Based on the biological characteristics of laccase, silk fabric was colored after being treated by laccase. The influence of doses of laccase, temperature, time and pH on the coloring result was studied. Mealwhile various dyeing fastness and evenness were tested. The mechanism of silk fabric coloration was analysized by infrared spectrum. The result showed the optimum dyeing process of laccase on silk fabric was obtained, the amount of laccase was 50%(o.w.f), temperature was 50℃, time was 24h, pH was4. And evenness, fastness of washing and rubbing of silk fabric were very good. Acid resistance stability of colored silk fabric was also good. But color fastness to light was weak. Infrared analysis showed that tyrosine of silk fabric was changed into quinone to obtain color.

Key words: laccase, silk fabric, dye-free, coloration