| abstract |
The present invention provides a polyisocyanate curing agent and the like, which are a structural unit derived from a diisocyanate, a structural unit derived from a polyester polyol, and a structural unit derived from the formula (1) (wherein R 1 is an alkylene having 1 to 4 carbon atoms) group, R 2 is an alkyl group having 1 to 4 carbon atoms; the average number of n is 4.0 or more and 20.0 or less) the structural unit of the polyalkylene glycol alkyl ether as a constituent of the polyisocyanate curing agent, The isocyanate group content is 5.0 mass % or more and 20.0 mass % or less, and the molar ratio of the urethane group derived from the polyalkylene glycol alkyl ether to the urethane group derived from the polyester polyol is 0.03 or more and 2.5 or less. |