| 摘要 |
PURPOSE:To improve voltage withstanding properties, heat-dissipating properties and humidity resistance, by previously coating an inorganic filler with a silicon- type coupling agent and/or a titanate-type coupling agent and adding the inorganic filler in a thermosetting resin for providing an insulating humidity- resistive layer. CONSTITUTION:An insulating moisture-resistive layer 3 interposed between a metallic foil 2 and a metallic heat-dissipating substrate 4 for bonding them integrally is composed of a thermosetting resin composition in the semi-cured state consisting of a thermosetting resin and of an inorganic filler coated with a silicone-type coupling agent and/or a titanate-type coupling agent, the inorganic filler being contained in the composition in a proportion of 20-300 parts by weight per 100 parts by weight of the thermosetting resin. Thereby, it is possible to improve voltage withstanding properties, heat dissipating properties and humidity resistance. |
