| 摘要 |
PROBLEM TO BE SOLVED: To provide an aqueous dispersion of a polyurethane resin which is free from an organic solvent or contains only a small amount of it and has excellent storage stability, a method of producing the same, and a sheet material using the aqueous dispersion. SOLUTION: The aqueous dispersion (B) of a polyurethane resin is composed of an aqueous dispersion (A) of an isocyanate-terminated prepolymer which is composed of water and an isocyanate-terminated prepolymer (a) dispersed in it, which is free from a surfactant or has a content of a surfactant of 18 wt.% or less based on the weight of (a), which is free from a solvent or has a content of a solvent of 5,000 ppm or less based on the weight of (a), which contains 60-85 wt.% of (a), which has an average particle diameter of the particles of dispersed (a) of 10-1,000 nm, and which has a content of particles having a particle diameter of more than 5,000 nm of 1 % or less based on the volume. COPYRIGHT: (C)2005,JPO&NCIPI |
