Production of polyurethane dispersions for use, e.g. in coating materials, involves making a prepolymer from macro-ol, ionic polyol and excess polyisocyanate, reacting with poly-amine, neutralizing and dispersing in water

摘要

The production of polyurethane dispersions involves: (a) making an NCO-terminated prepolymer from macro-ols, ionic or potentially ionic polyols and excess polyisocyanate; (b) reacting with compounds with at least two isocyanate-reactive amino groups at an NCO/NH group ratio of not more than 1:1; then (c) neutralizing; and (d) dispersing with water. An Independent claim is also included for polyurethane dispersions obtained by this method.