AQUEOUS POLYURETHANE RESIN DISPERSION AND SHEET MATERIAL OBTAINED FROM THE SAME

摘要

An aqueous isocyanate-terminated-prepolymer dispersion (A) which comprises water and an isocyanate-terminated prepolymer (a) dispersed therein, the dispersion containing no surfactant or having a surfactant content of 10 wt.% or lower based on the prepolymer (a), the dispersion containing no solvent or having a solvent content of up to 5,000 weight ppm of the prepolymer (a), and the content of the prepolymer (a) being 60 to 85 wt.%. Also provided is an aqueous polyurethane dispersion (B) containing 20 to 65 wt.% polyurethane resin (b) obtained by subjecting the dispersion (A) to a chain extension reaction. The aqueous polyurethane resin dispersion has excellent storage stability. This aqueous dispersion is less apt to catch fire and is highly safe for the human body. It is applicable to a polyurethane resin sheet material, coating material, adhesive, pressure-sensitive adhesive, or fiber-treating agent which all are friendly to the environment. It is useful also for producing a leather-like polyurethane resin sheet material prevented from suffering migration.