纺织涂层 化学品

Microporous polyurethane coatings (direct coating by wet phase inversion or dry coating) create a porous structure permeable to moisture vapor but impermeable to liquid water. Hydrophilic polyurethane coatings (monolithic) transport moisture through polymer chain diffusion without pores — used in high-quality outdoor garments. PTFE membrane laminates bonded with PU adhesive are the premium breathable waterproof solution.

C8 perfluorooctyl-based DWR has been phased out due to PFAS persistence concerns. C6 fluorocarbon DWR has reduced environmental persistence but is also under scrutiny. Current alternatives include dendrimer-chemistry PFAS-free DWR, paraffin wax/silicone blends (lower durability), and PTFE-based dispersions. Bio-based DWR agents are in development. Durability of PFAS-free alternatives continues to improve but is not yet equivalent to C8.

Waterborne PU dispersions (PUD) are the standard for textile coatings replacing solventborne DMF-based systems. Aliphatic isocyanate-based PUDs (HDI, IPDI) provide UV stability for outdoor textiles. Polyester-based PUDs give higher rigidity and strength for technical applications. Polycarbonate PUDs offer excellent hydrolysis resistance for marine and outdoor use.

Flame-retardant coatings combine binder (typically PVC plastisol or PU) with halogenated FR (decabromodiphenyl ethane, replacing decaBDE) and antimony trioxide synergist. Halogen-free FR systems use ammonium polyphosphate, melamine cyanurate, or aluminum trihydrate. Standards include NFPA 701 (drapes), FAR 25.853 (aircraft), and EN 13501 (building textiles), with vertical or horizontal burn testing on the coated fabric.

Tarpaulin and truck-cover textiles: 600–900 g/m² total PVC plastisol. Awning fabrics: 250–400 g/m² acrylic or PU coating. Outdoor garment shell: 25–80 g/m² PU coating for waterproof-breathable. Geotextile waterproofing membranes: 1.5–3 mm bituminous or PVC coating. Coating weight is measured per ISO 2286 — critical for both performance and compliance with project specifications.

Antimicrobial coatings incorporate silver-, zinc-, or copper-based active ingredients at 0.1–1% with PU or acrylic binder. Quaternary ammonium silanes provide durable bonding to fiber. Triclosan (under regulatory pressure) and zinc pyrithione are used in healthcare textiles. Performance is tested per ISO 20743 (antibacterial activity) or AATCC 100 with target log reduction of >2 against E. coli and S. aureus after multiple wash cycles.