Silver Nanoparticle (AgNP) Textile Finishing

Silver nanoparticles (AgNPs, 5–20 nm, synthesized by chemical reduction of AgNO₃ with NaBH₄ or citrate) are applied to textiles via pad-dry-cure (100–150°C, 2–3 min) at 50–300 ppm silver loading. Electrostatic or covalent binding to fiber surface uses silane coupling agents or chitosan binders for durability. Bactericidal efficacy exceeds 5 log reduction (99.999%) against S. aureus and E. coli per AATCC TM100. Wash durability of 20–30 cycles at 40°C is achievable with binder systems; fiber-embedded AgNPs in melt-spun polyester last 50+ cycles. Silver release rate of 0.1–5.0 µg/cm²/day raises ecotoxicity concerns; REACH and EPA regulate total silver content below 5,000 ppm in finished textiles.