ZnO Nanoparticle Padding Antimicrobial Finish
topic
ZnO nanoparticles (30–80 nm, surface area 15–25 m²/g) dispersed in aqueous medium (0.5–5.0% w/v with dispersant) are applied to cotton or polyester via 2-roll padder at 70–80% wet pickup, dried at 100°C for 3 min, and cured at 140–160°C for 2–3 min. Binders (polyurethane or acrylic at 10–20 g/m²) improve wash durability from 10 to 30–40 cycles (ISO 6330 at 40°C). Bactericidal log reduction of 3.5–4.5 against S. aureus (AATCC TM100). UV protection factor (UPF) increases from 5–10 to >50 for cotton fabric. Zn²⁺ release rate of 0.05–0.5 mg/L in wash effluent requires effluent monitoring per ZDHC WWGP. Treatment cost is $0.08–0.18/m², making it significantly more economical than silver-based systems.
Role
Primary industrial route for applying ZnO antimicrobial and UV-protective finish to sportswear and medical socks at mass-production scale, combining dual functional benefits at lower cost than silver nanoparticle alternatives.