Patent attributes
A method for producing a printed wiring board which is capable of forming an insulating layer having a surface with low roughness and high adhesion strength to a conductive layer and of achieving an excellent performance in removal of smear, involves the following steps (A) to (F) in this order: (A) laminating, onto an internal layer circuit substrate, a resin sheet with a support which includes a support and a resin composition layer in contact with the support so that the resin composition layer is in contact with the internal layer circuit substrate; (B) thermally curing the resin composition layer of the resin sheet with a support to form an insulating layer; (C) perforating the insulating layer to form a via hole; (D) performing a desmear treatment; (E) peeling the support; and (F) forming a conductive layer on a surface of the insulating layer.