| 摘要 |
PURPOSE:To obtain an insulating layer having a flat and smooth surface by a method wherein the insulating layer obtainable by adding an acrylic leveling agent to an epoxy insulating resin is provided. CONSTITUTION:An internal layer circuit 2 is formed on the surface of an insulating substrate 1. A primer layer 3 is applied on the surface of this substrate 1 and an insulating layer 4 is applied on the surface of the layer 3. The layer 4 is a coat of epoxy resin with an addition of 0.2wt.% or more of an acrylic leveling agent. Thereby the smoothness of the surface of a multilayer wiring board 10 is improved and the improper short-circuit of an external layer circuit 8 can be reduced. |
