| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a polyurethane resin aqueous dispersion excellent in coatability, contact adhesion just after lamination, initial and final adhesive strength, and heat-resistant creep. SOLUTION: This method for producing the polyurethane resin aqueous dispersion comprises the following process: a prepolymer D obtained by reaction between a polyisocyanate A and a polyol B 10-350 in hydroxy number in an organic solvent C in the equivalent ratio: NCO group/hydroxy group of (2.00-1.01):1.00 is mixed with an aqueous solution F containing at least one surfactant E selected from a dialkylsulfosuccinic acid metal salt, organic salt of the acid, alkylbenzenesulfonic acid metal salt and organic salt of the acid, and the mixture is mechanically emulsified and dispersed into an aqueous dispersion G, which is then mixed with a polyamine H<=300 in molecular weight and >=2 in functional group number with the equivalent ratio:amino group/NCO group of <=1.9 based on the NCO group in the prepolymer D to effect chain extension; wherein the components B and/or H contain carboxylate group and/or sulfonate group. The thus obtained aqueous dispersion has a mean particle size of <=1μm with the standard deviation being <=1μm.
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