| 摘要 |
PROBLEM TO BE SOLVED: To form at a low temperature a paint film which is excellent in adhesion to substrate, impact resistance, flexibility, etc., good in corrosion resistance, finish properties by a method wherein powder coating material composed of a specific composition is applied to an outer surface of a cast iron pipe. SOLUTION: An amount of a phenolic hydroxyl group of a hardener of 200-800 g/eq average phenolic hydroxyl group equivalent, being a compound expressed by the formula 1 is 0.5 to 1.2 equivalent to 1 equivalent of an epoxy group of bisphenol A type epoxy resin of 600 to 2000 g/eq epoxy equivalent at 75 to 128 deg.C softening point. Further, an amount of dicyandiamide to the hardener is 3 to 20 wt.%. Powder coating material wherein an amount of imidazole cure accelerator and/or imidazoline cure accelerator to an amount of the hardener is 0.1 to 15.0 wt.%, is applied onto an outer surface of a cast iron pipe. Thereby, a paint film which is excellent in adhesion to a substrate, impact resistance, flexibility, etc., and good in corrosion resistance, and finish properties can be formed at a low temperature. |
