POLYURETHANE RESIN COMPOSITION FOR DURABLE MOISTURE-PERMEABLE WATERPROOF SHEET, MOISTURE-PERMEABLE WATERPROOF SHEET, AND PROCESS FOR PRODUCING THE SAME

摘要

A urethane resin composition for use in a moisture-permeable waterproof sheet which is excellent in moisture permeability and waterproofing properties, has resistance to chemicals including insecticides and organic solvents, and has excellent durability. The polyurethane resin composition for moisture-permeable waterproof sheets is characterized by comprising a hydrophilic polyurethane resin (A), an organic polyisocyanate (B) comprising a polyisocyanate (B0) having 3 or more functional groups, and an organic solvent (C). The hydrophilic polyurethane resin (A) preferably is one obtained from a polymeric diol (d) containing oxyethylene groups, an organic diisocyanate (e), and a chain extender (f) and having an oxyethylene group content of 10-80 mass%. The organic polyisocyanate (B) preferably is at least one member selected from the group consisting of aliphatic polyisocyanates and alicyclic polyisocyanates each having 2.3-5 functional groups on the average.