PURPOSE: To obtain a cured product having excellent acid resistane and toughness by the cross-linking reaction between an acrylic resin obtained by copolymerizing an acrylic monomer having an enol ester group with another vinyl monomer and an active hydrogen compound.

CONSTITUTION: The cured resin is prepared by the cross-linking reaction between an acrylic resin [A] obtained by copolymerizing 1-20wt.% acrylic monomer (a) represented by the formula (wherein R1 is hydrogen or methyl; R2 and R3 are each hydrogen, 1-20C alkyl or 6-20C aryl) with 35-95wt.% hard monomer (b) selected from among a styrene monomer, acrylamide, metharylamide and methyl metharylate and 0-40wt.% ethylenically unsaturated monomer (c) other than components (a) and (b), and a polyhydroxy compound [B] (a compound having at least two active hydrogen atoms).