Polyurethane dispersion (PUD) with improved isopropanol resistance, flexibility and softness

摘要

Isocyanate-functional polyurethane prepolymers and aqueous dispersions therefrom which are useful for the production of flat materials having excellent resistance to alcoholic solvents are described. The prepolymers are prepared by reacting A) an isocyanate selected from the group consisting of i) an aliphatic and/or a cycloaliphatic isocyanate; and ii) a mixture of an aromatic isocyanate and an aliphatic and/or a cycloaliphatic isocyanate; and B) a polyester diol having a number average molecular weight of 800 to 4,000 and a polyether triol having a number average molecular weight of 200 to 3,000.