Curable resin composition, coating composition, coating method and coated article

A curable resin composition comprising

• 5 to 80 weight %, based on the nonvolatile matter in the resin composition, of a polymer containing free and esterified carboxyl groups and having an acid value of 50 to 300 mg KOH/g (1e) as obtained by reacting an acid anhydride group-containing polymer (1c), which is obtained by copolymerizing 10 to 40 weight %, based on the total amount of monomers constituting (1e), of an acid anhydride group-containing ethylenically unsaturated monomer (1a) with 90 to 60 weight %, based on the total amount of monomers constituting (1e), of a copolymerizable other ethylenically unsaturated monomer (1b), with a monohydric alcohol of 1 to 12 carbon atoms (1d) in the ratio (the number of mols of acid anhydride group in acid anhydride-containing polymer (1c))/(the number of mols of hydroxyl group in monohydric alcohol (1d)) of 1/10 to 1/1,
• 1 to 80 weight %, based on the nonvolatile matter in the resin composition, of a hydroxyl group- and epoxy group-containing polymer having an epoxy equivalent of 200 to 1000 and a hydroxyl equivalent of 250 to 1500 (2d) as obtained by copolymerizing 5 to 60 weight %, based on the total amount of monomers constituting (2d), of a hydroxylalkyl (meth) acrylate monomer (2a) of the general formula (I):
• ##STR5## wherein R represents hydrogen or methyl;
• A represents a straight-chain or branched alkylene group of 2 to 8 carbon atoms;
• y represents a whole number of 3 to 7;
• z represents a whole number of 0 to 4;
• with 10 to 60 weight %, based on the total amount of monomers constituting (2d), of an epoxy group-containing ethylenically unsaturated monomer (2b) and 0 to 85 weight %, based on the total amount of monomers constituting (2d), of an ethylenically unsaturated monomer (2c) copolymerizable therewith, and
• 1to 50 weight %, based on the nonvolatile matter in the resin composition, of an epoxy group- and alkoxyl group-containing silicone polymer (3a) of the general formula (II):
• ##STR6## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, and R.sup.6 are the same or different and each represents alkyl of 1 to 10 carbon atoms, phenyl, phenethyl, alkoxyl of 1 to 5 carbon atoms, R.sup.7 -Si(OR.sup.8).sub.3, R.sup.7 -Si(OR.sup.8).sub.2 CH.sub.3, R.sup.7 -Si(OR.sup.8)(CH.sub.3).sub.2, or R.sup.7 -Y;
• R.sup.7 represents a straight-chain or branched alkylene group which may have an ether bond and/or an ester bond;
• R.sup.8 represents alkyl of 1 to 5 carbon atoms;
• Y represents an epoxy group-containing acyclic or cyclic hydrocarbon residue;
• q represents a whole number of 1 to 20, m represents a whole number of 0 to 4, n represents a whole number of 0 to 2;
• the order of the parenthesized groups occurring in q, m and n repetitions are random and not restricted to the formula shown,
• wherein the molar ratio of the carboxyl group contained in said polymer containing free and esterified carboxyl groups (1e) to the epoxy group contained in said hydroxyl group- and epoxy group-containing polymer (2d) and the epoxy group contained in said epoxy group- and alkoxyl group-containing silicone polymer (3a), carboxyl group/epoxy group ration is 1/1.6 to 1/0.6.