| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject composition excellent in coating film strength, bond strength, chemical resistance, heat cycle resistance and durability, exhibiting good electrical resistance characteristics even under high humidity, thus useful as a powder coating material for electrical insulating coating use, comprising an epoxy resin and a specific curing agent. SOLUTION: This powder coating composition comprises (A) an epoxy resin and (B) a curing agent containing >=10wt.% of (B1 ) a phenolaralkyl resin obtained by reaction between (B1 ') anα,α'-dihaloxylene compound and (B1 ") a phenolic compound in the presence of no catalyst or a hydrogen halide catalyst. For example, the amount of the component B to be used is such as to be 0.5-1.5 (esp. 0.8-1.1) in terms of OH equivalent ratio based on the epoxy group in the component A. It is preferable that the component B1 is prepared by reaction between the components B1 ' and B1 " in the molar ratio B1 "/B1 ' of 0.5-10 (esp. 0.7-2) at 60-200 (esp. 70-160) deg.C.
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