| abstract |
The invention provides a resin composition, which is formed by hardening an insulating layer. In the wet roughening step, not only the arithmetic average roughness of the surface of the insulating layer is small, but also the root mean square roughness of the surface of the insulator is small. A conductive layer with sufficient peel strength can be formed on the insulating layer by plating, and the dielectric tangent of the hardened material is low.nn n n The resin composition of the present invention is characterized by containing any one or both of an epoxy resin having a naphthylfluorene structure, an active ester-based hardener, and an isocyanate-based hardener. |