Fabrication of multifunctional cotton fabrics dyed with Coptis chinensis extract

Low dye exhaustion and poor colorfastness of cotton fabrics dyed with natural dyes were the inevitable issues, which may potentially limit their application in textile industries. Hence, there is great demand for improving dyeing performance of natural dyes to expand their application. This work presents a facile and efficient way to improve dye exhaustion and color fastness of cotton fabrics dyed with Coptis chinensis (C. chinensis) extract through fabric pretreatment and aftertreatment processes. The cotton fabrics were firstly treated with critic acid (CA) to increase their capacity of anionic sites. Enhanced effect of water repellent agent as the aftertreatment chemical, which was applied to improve washing fastness of dyed fabrics, was evaluated. The color character-istics, color fastness and functionalities of dyed fabrics were also assessed. The results indicated that pretreated cotton fabrics displayed higher color strength than the untreated fabrics. Additionally, the dyed fabrics treated with water repellent agents showed better washing fastness. The antibacterial activity of dyed fabric was increased up to 98% and the ultraviolet protection factor (UPF) value reached 349.69. What's more, the dyed fabrics also exhibited excellent wrinkle resistance and waterproof property. The integration of antibacterial, antiultraviolet, antiwrinkle and waterproof properties in the cotton fabrics dyed with C. chinensis extract was a meaningful achievement, which exhibited great potential application in medical textile and garment.