| 摘要 |
PURPOSE:To enhance the heat cycle resistance and humidity resistance of a part by a method wherein an under coating material containing a phenol resin and epoxidized polybutadiene is applied to an electric/electronic part and, after curing, powder paint is applied to the under coating layer. CONSTITUTION:About 15-85wt.% of a phenol resin and about 85-15wt.% of epoxidized polybutadiene are used to the sum amount of the phenol resin and epoxidized polybutadiene and dissolved in a solvent such as a hydrocarbon solvent to prepare an under coating material. This under coating material is applied to the surface of an electric/electronic part and, after curing, powder painting is applied thereon. As the phenol resin there are a resole type phenol resin and a novolac type phenol resin and expoxidized polybutadiene is obtained by adding a plurality of epoxy groups to the main chain or terminal of polybutadiene. |
