Nanosilver Antibacterial Finishing of Printed Silk Fabric with Madder Natural Dye

With developments in technology and finishing processes, the antibacterial properties of textiles are increasingly regarded as important. In the present work, the nanosilver antibacterial finishing was investigated on printed silk fabric with madder natural dye using Response Surface Methodology. The effects of four parameters—dye concentration, nanosilver concentration, mordant concentration, and alginate concentration—were analyzed. First, the madder dye was extracted using methanol solvents in a Soxhlet extraction system. The extract of madder was used for printing on silk fabric. Antibacterial finishing was performed by coating the silk fabric with nanosilver before and after printing. The samples were evaluated by measuring color strength, lightness, chroma, hue, washing fastness, and antibacterial properties as the diameter of the non-growth halo. The results show that the difference between the diameters of the non-growth halo of pre-finishing and post-finishing methods is not significant. In the pre-finishing method, the effects of dye and nanosilver on the non-growth halo are significant. In the post-finishing method, the effects of alum and nanosilver are significant. The washing fastness in the post-finishing method is better than in the pre-finishing method. The average, maximum, and minimum color differences between the two methods are 13.52, 33.51, and 3.48, respectively. In the pre-finishing method, the parameters of madder dye, mordant, and nanosilver have a significant effect on color strength. In the post-finishing method, the effects of madder dye and alum mordant are significant. The results show that the order of printing and finishing with nanosilver affects the shade, color depth, antibacterial properties, and wash fastness of silk fabric. The best results are obtained when the antibacterial finishing with nanosilver is performed first.