Polyurethane dispersion and method for producing the same

摘要

A polyurethane dispersion is obtained by aqueously dispersing an aqueous polyurethane resin obtained by reaction of an isocyanate group-terminated urethane prepolymer with a chain extender. The isocyanate group-terminated urethane prepolymer contains an adhesive urethane prepolymer for imparting adhesion and a gas-barrier urethane prepolymer for imparting gas barrier properties.

主权项

1. A polyurethane dispersion obtained by aqueously dispersing an aqueous polyurethane resin obtained by reaction of an isocyanate group-terminated urethane prepolymer with a chain extender,
wherein the isocyanate group-terminated urethane prepolymer comprises an adhesive urethane prepolymer for imparting adhesion and a gas-barrier urethane prepolymer for imparting gas barrier properties, the adhesive urethane prepolymer is obtained by reaction of a polyisocyanate component and a polyol component comprising a high-molecular-weight polyol having a number average molecular weight of 400 to 10000, and the gas-barrier urethane prepolymer is obtained by reaction of a polyisocyanate component and a polyol component not comprising the high-molecular-weight polyol but comprising a low-molecular-weight polyol having a number average molecular weight of less than 400 and being selected from an alkane polyol having 2 to 6 carbon atoms and/or a polyoxyalkylene glycol having 2 to 6 carbon atoms, wherein the polyurethane dispersion has a solid content of 5% to 50% by weight.