Dyeing Nylon-6 Fabric with New 2-Chloro-N-(4-Aryl-5-Arylazo-Thiazol-2-Yl)-Acetamide Dyes in Supercritical Carbon Dioxide

A number of new reactive disperse dyes were synthesized from 2-chloro-N-(4-aryl-5-arylazo-thiazol-2-yl)-acetamide derivatives (5a–d). The new dyestuffs were applied to dye the nylon-6 fabric in supercritical carbon dioxide (scCO2). The chemical structures of these new dyes were explained by elemental and spectroscopic analyses. Then, the suitability of dyestuffs under study for textile dyeing as disperse reactive dyes was reported. All four dyes (5a–5d) exhibited strong color strength, which may be attributed to excellent dye penetration in the fabric afforded by scCO2. The color fastness of dyed samples was measured, and the results demonstrated excellent values and extremely satisfactory washing durability. The dyed samples showed excellent antibacterial activity against Bacillus cereus, Staphylococcus aureus (G+ bacteria), and Escherichia coli (G− bacteria) compared with selected antibiotics as a reference standard; the retention of this excellent antibacterial activity was still satisfactory even after five washing cycles.