PURPOSE: To provide a resin composition containing a polymer of a specific vinyl ether monomer and a curing catalyst, having excellent storage stability as a one-pack composition, giving a cured product having excellent acid resistance, weather resistance, etc., and good coating film appearance and useful in the field of automotive industry.

CONSTITUTION: This resin composition contains (A) a polymer of a vinyl ether monomer of formula I (R1 is a 1-5C alkyl; (n) is 1-4) and (B) a curing catalyst. For example, the component A is a polymer produced by polymerizing a vinyl ether monomer of formula II by a solution radical polymerization using toluene, etc., as the solvent and the component B is e.g. a catalyst for opening a cyclocarbonate group, e.g. tetramethylammonium bromide. The amount of the component B is preferably 1-5 pts.wt. based on 100 pts.wt. of the solid content of the component A.