Zinc Pyrithione (ZPT) Antifungal Treatment
topic
Zinc pyrithione (ZPT, bis(2-pyridylthio)zinc 1,1'-dioxide, MW 317 g/mol) is applied to textiles at 0.3–1.0% owf via pad-dry-cure (120–140°C) or exhaustion, chelating to fiber surfaces through pyridine-N and thiolate-S coordination. ZPT disrupts fungal membrane transport and inhibits electron transport chain at MIC of 0.5–5 µg/mL against Trichophyton rubrum. Antifungal efficacy of >3 log (ISO 13629) and antibacterial >2 log (AATCC TM100) are achieved simultaneously. Wash durability of 25–35 cycles at 40°C with nonionic binder. ZPT at ≤0.5% owf meets Oeko-Tex Standard 100 for skin-contact products. Primary application is antifungal hosiery ($0.10–0.25/m²) and athletic shoe linings treating the 15% adult population affected by tinea pedis annually.
Role
Dual antibacterial-antifungal finish for performance hosiery, athletic insoles, and diabetic socks, providing clinically relevant protection against athlete's foot pathogens while maintaining skin safety compliance for direct skin-contact applications.