A novel approach to modify and functionalize acid black 1 dye for antimicrobial and UV protective textiles

Due to the focus on the development of environment-friendly and hygienic textiles, a novel and sustainable approach was adopted to functionalize acid dye for cotton dyeing to develop durable antibacterial and ultraviolet protective fabric. Functionalization of commercial acid dye was carried out by incorporation of triazine reactive system and antibacterial agent (chloroxylenol) into dye structure. The modified bioactive reactive dye was characterized by 1H NMR, 13C NMR, FTIR, and UV–Vis spectroscopy. The exhaust dyeing approach was used for the application of dye on cotton. Antibacterial efficacy of modified dye powder and dyed fabric against Escherichia coli and Staphylococcus aureus was evaluated quantitatively and qualitatively following standard testing protocols. Fastness properties, levelness of dye, colorimetric data (L*, C* a*, b*, H*), and color strength (K/S) of dyed cotton fabric were also assessed. The dye exhibited remarkable antibacterial potential with 99.9% bacterial growth reduction with nearly the same results after 20 industrial laundering cycles. Ultraviolet Protection Factor (UPF) of dyed unwashed and washed fabric, measured according to standard AATCC-183, was >100. The dyed fabric showed good durability to light, washing, and rubbing fastness. The excellent antibacterial potential and remarkable durability to washing is due to the incorporation of chloroxylenol and triazine reactive system in acid dye structure. Thus, the development of such functional reactive dyes with durable antibacterial activity will be fruitful in the future in terms of sustainability for desired applications. Moreover, all commercially available acid dyes can be made reactive for functional dyeing of cotton by adopting this route.