A sustainable route for antibacterial nanofinishing of textiles

In this paper, an aerosol-based process is shown for imparting antibacterial property to textiles. Metal nanoparticles (copper and silver) are produced by means of DC electrical discharges (glow and arc) between two electrodes in nitrogen at ambient pressure and passed through textile fabrics (cotton, polyester and lyocell) which act as filter media. The particle retention efficiency of the fabrics is measured in dependence of particle size and face velocity. The antibacterial performance of the fabrics treated with metal nanoparticles and its durability to wash is assessed according to industry standards. Loads of about 200 ppm (2x10-2 %wt.) of nanoparticles of copper or silver give strong antibacterial property but the colour and hand feeling of the fabrics are significantly affected. Nanosilver loads in the order of 50 ppm (5x10-3 %wt.) impart comparably high antibacterial property to the fabrics with no visible impact on colour and hand touching, and wash fastness is proven for 10 washes. Small silver nanoparticles (<5 nm) result in much less release of silver to wash water, with respect to larger nanoparticles (>20 nm).