Antibacterial Finishing of Vat Dyed Cotton Fabrics with a Reactive N -Halamine

To obtain antibacterial properties for colored cotton fabrics, vat dyes were chosen to dye cotton because they can avoid serious discoloration during chlorination. In this study, we synthesized a reactive N-halamine precursor, 4-(4-(2,2,6,6-tetramethyl-4-piperidinol)-6-chloro-1,3,5-triazinylamino)-benzenesulfonate (BTMPT), and coated it on colored cotton fabrics that were dyed with three different vat dyes. The optimum pH for chlorination of the treated cotton fabrics was investigated. Chlorination at pH 11 achieved a small color difference and greater than 0.2% of active chlorine loading. When challenged, the chlorinated fabrics inactivated all inoculated Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) within 5 min. The treated cotton fabric had greater breaking strength than those treated with the traditional process, as well as good washing stability.