Patent ID: 7786242

Claim:
A ring-containing modified resin represented by: chemical formula (1)′ of an adduct obtained by an addition reaction or multiple addition reactions of a resin compound, an organic diisocyanate, and an alcohol derived from a polyol selected from the group consisting of a polyether polyol, a polyester polyol, and an acrylic copolymer including hydroxyl groups; or chemical formulas (2)′ or (3)′ of an adduct obtained by an addition reaction or multiple addition reactions of a resin compound, an organic diisocyanate, and a polyol selected from the group consisting of a polyether polyol, a polyester polyol, and an acrylic copolymer including hydroxyl groups: R 1 [—O—CO—NH—R 2 —NH—CO—O—R 3a —O—R 4 ] q (1)′ or R 1 [—O—CO—NH—R 2 —NH—CO—O—R 3b —O—H] q (2)′ or R 1 [—(—O—CO—NH—R 2 —NH—CO—O—R 3c ) p —O—H] q (3)′ wherein: R 1 is a group derived from the resin compound represented by R 1 —(OH) q as a xylene resin including a hydroxyl group; —R 2 — is a group derived from the organic diisocyanate represented by OCN—R 2 —NCO; —O—R 3a —O—R 4 of (1)′ is a group derived from the compound represented by H—O—R 3a —O—R 4 in which —R 4 is an alkyl group having 1 to 18 carbons or a phenyl group, and —R 3a — is a group derived from the polyol having two hydroxyl groups and a number-average molecular weight of 200 to 30000; —O—R 3b —O—H of (2)′ and —O—R 3c —O— of (3)′ are a group derived from the compound represented by H—O—R 3b —O—H and H—O—R 3c —O—H, respectively, in which —R 3b —, and —R 3c — is a group derived from the polyol having two hydroxyl groups and a number-average molecular weight of 200 to 30000; q is the number of hydroxyl groups of the resin compound; and p is 2 to 3.