Influence of fixing treatment on the color fastness and bioactivities of silk fabric dyed with curcumin

The curcumin dyed silk has poor color fastness to wash, rub, and light. Two cationic polyamine fixing agents, one cationic etherifying agent and one cross-linker were applied to the fixing treatment of the curcumin dyed silk fabric. The color parameters, color fastness, and antioxidant and antibacterial bioactivities of the treated silk fabrics were determined. All the fixing treatments increased the rub and light fastness. In comparison to the non-reactive fixing agents, the cross-linker and etherifying agent exhibited stronger ability for improving the rub fastness and the wash fastness for staining, but they had greater influence on the color parameters due to their alkaline application conditions. Fixing treatment caused a great decrease in antioxidant activity, and a minor decrease in antibacterial activity. Among the four fixing agents, the cross-linker exerted the greatest impact on antioxidant and antibacterial activities due to its high ability of reaction with the phenolic hydroxyl groups of curcumin.