Polyurethane Coating
category
Polyurethane (PU) coating applies solvent-based (DMF, 15–30% solids) or water-based PU dispersions onto textile substrates using knife-over-roll or gravure methods, achieving add-on weights of 30–150 g/m². Hydrostatic head resistance of 1,000–20,000 mm H₂O is achieved depending on coat weight and formulation. Moisture vapor transmission rates (MVTR) of 2,000–10,000 g/m²/24h are attainable with microporous PU. Dry and wet coating processes differ in porosity control. Solvent recovery systems reduce DMF emission to below 10 mg/m³ per workplace safety regulations.
Role
Dominant coating technology for waterproof-breathable outerwear, tents, luggage, and upholstery fabrics, balancing water resistance and breathability at a cost of $0.50–3.00/m² depending on performance grade.