Patent ID: 8022138

Claim:
An aqueous polyurethane dispersion containing from 5 to 70 weight percent polyurethane solids wherein the solids are obtained from at least one isocyanate terminated prepolymer prepared by reacting (a) a polyol or polyol blend having a mean average equivalent weight of 200 to 2,000; and (b) at least one polyisocyanate where the prepolymer is dispersed in water; optionally in the presence of (c) 0.01 to 8 parts by weight of the polyurethane of one or more surfactants; and (d) one or more amine chain extenders; wherein the prepolymers have an isocyanate content of from 2 to 40 weight percent and the polyol or polyol blend (a) contains at least 15 weight percent of a polyester based on a C2 to C12 polycarboxylic acid and a glycol component, wherein the glycol component contains isomers of 1,3- and 1,4-cyclohexanedimethanol where the ratio of the 1,3-/1,4-isomers is from 35:65 to 65:35.