WATER-BASED UNDERCOATING COMPOSITION

摘要

PROBLEM TO BE SOLVED: To provide a water-based undercoating composition highly adhesive to a substrate and an existing coated film without using any chlorinated polyolefin resin. SOLUTION: The water-based undercoating composition comprises an emulsion resin obtained by emulsion polymerization of a monomer mixture containing an acetacetoxy group-containing unsaturated monomer and an aliphatic dihydrazide compound; wherein the emulsion resin has a glass transition temperature of preferably -10 to 50°C and the molar ratio of the hydrazide groups in the aliphatic hydrazide compound to the carbonyl groups in the emulsion resin with both the ends bound to no heteroatoms is preferably≤1, more preferably 0.3-0.7. COPYRIGHT: (C)2003,JPO