Aqueous polyurethane dispersion adhesive compositions with improved heat resistance

摘要

Aqueous dispersion adhesives of anionic polyurethanes which have high heat resistance and low activation temperature, even when employed without addition of a crosslinker. The polyurethane is the reaction product of an isocyanate terminated polyurethane prepolymer, and a chain extender. The polyurethane prepolymer is the reaction product of a polyol component and a diisocyanate component, the polyol component including: a sulfonated polyester polyol, a hydroxy carboxylic acid of the formula:(HO)xR(COOH)y wherein (R) represents a straight or branched, hydrocarbon radical containing 1 to 12 carbon atoms, and x and y represent values from 1 to 3, and a low molecular weight aliphatic diol having a molecular weight of from 60 to 400.