| 摘要 |
PROBLEM TO BE SOLVED: To make formable a coating film excellent in durability, acid resistance, external appearance and weathering resistance by incorporating a polyester resin bearing at least one silyl group at the end of a molecular chain in a specific ratio. SOLUTION: The resin composition for powder coating comprises as an essential component a polyester resin (A) bearing at least one silyl group represented by the formula at the end of the molecular chain. The component A bears the silyl group of the formula as a main crosslinkable group, has a glass transition temperature of 40-100 deg.C and a number average mol.wt. of 2,000-20,000 and forms at least 30 wt.% of all the crosslinkable polymers. In the formula, R1 is a 1-10C alkyl, 6-10C aryl or 7-10C aralkyl; X is H, a halogen, hydroxyl, alkoxyl or the like; and a is an integer of 0-2. This composition comprises 0.001-10 pts. by wt. of a curing catalyst based on 100 pts. by wt. of the component A. As the curing catalyst is employed, for example, an organic sulfonic acid, an organic metal compound or the like.
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