| 摘要 |
PURPOSE:To obtain a printed wiring board having a high degree of adhesive strength with a foil without losing an excellent heat radiating property by a method wherein a conductive foil is provided by superposing a high thermal conductive insulating layer having a large compounding quantity of metal oxide and a low thermal conductive insulating layer having a small compounding quantity on a metal base. CONSTITUTION:An Al foil 3 is provided on the base 1, on which an Al or alumite treatment is performed, by laminating a high thermal conductive insulating layer 9, whereon 80-90 wt. % of Al2O3 and the like of grain diameter 1-10 mum or thereabout is dispersed into epoxy resin, and a low thermal conductive insulating layer 10 of 40-60 wt. %. According to this constitution, as the layer 9 has the high compounding ratio of high thermal conductivity, it radiates heat quickly, and the layer 10 has a high degree of adhesive strength with the Al foil 3, because its compounding ratio of Al2O3 is small. As a result, the high density mounding of high heat generating parts can be performed. |
