| 摘要 |
PURPOSE:To enable to secure excellent adhesive strength and heat conductivity without performing a special surface treatment even after impregnated resin is hardened by a method wherein grain-formed electric insulating material, having the coefficient of thermal conductivity higher than thermosetting resin, is dispersed into the thermosetting resin impregnated into a fibrous base material. CONSTITUTION:A closely woven glass fiber cloth and the like is used for the fiber-like base material 1 which is a reinforcing material of thin insulator, and the thickness (t1) of the base material 1 is 0.18mm or thereabout, for example. The thermosetting resin 2 selected from epoxy resin, polyester and the like is filled in the gap of the fibrous base material, the resin 2 is impregnated in such a manner that the surface of the base material is thinly coated with it, and the resin is brought into a semicured state. When the average film thickness of said thermosetting resin 2 coated on the surface of the base material is (t2), the entire thickness (t) of the thin insulating material becomes t=t1+2t2=0.23-0.25mm or thereabout. A grain-like electric insulating material 3, having the coefficient of thermal conductivity higher than that of the thermosetting resin 2, is dispersed in the thermosetting resin 2. Silica and the like of 200mum or less in grain diameter can be used as the electric insulating material 3. |
