Polyurethane aqueous dispersion, adhesive, synthetic leather and paint

Abstract

There is provided an aqueous polyurethane dispersion that makes it possible to prepare an adhesive, a paint, and the like capable of forming an adhesion layer as a cured film whose physical properties such as strength are unlikely to be changed even by a change in temperature, the aqueous polyurethane dispersion having excellent storage stability. The aqueous polyurethane dispersion is an aqueous polyurethane dispersion containing: resin particles formed with a polyurethane having a hydroxy group at a terminal thereof; and water as a dispersion medium, wherein the polyurethane has a structure derived from a urethane prepolymer, the urethane prepolymer has a constituent unit derived from a polyol containing a polyether polyol; a constituent unit derived from a polyisocyanate containing an aliphatic polyisocyanate and an alicyclic polyisocyanate; and a constituent unit derived from an acidic group-containing polyol, the polyurethane has an acid value of 30 mgKOH/g or lower, the polyol further contains a polycarbonate polyol, and the mass ratio of the polyether polyol (C) to the polycarbonate polyol (D), (C):(D), is 20:80 to 95:5.