Abstract: In one embodiment, an inner layer circuit pattern portion and a lead pattern portion are formed, an outer layer base material is prepared, an interlayer adhesive layer to which has been affixed in advance an inner layer separation film is prepared, the interlayer adhesive layer is layered on the outer layer base material, a molded inner layer separation film is formed by molding the inner layer separation film, the molded inner layer separation film is positioned on the lead pattern portion and the outer layer base material is layered on the inner layer base material with interposition of the interlayer adhesive layer, a conductor layer of the outer layer base material is patterned to form an outer layer circuit pattern portion, and the molded inner layer separation film is separated from the inner layer base material to remove the interlayer adhesive layer and the outer layer base material.

Abstract: A multilayer printed wiring board includes a flexible portion that is constituted from a flexible base material in which an inner layer circuit pattern has been formed, and a hard portion that is constituted from a hard base material that is layered on a portion of the flexible base material via an adhesive layer and in which an outer layer circuit pattern has been formed. The border of the flexible portion and the hard portion is covered by a covering layer that continuously covers the flexible base material and the hard base material, with an exposed portion of the inner layer circuit pattern being exposed. A plating layer is formed by performing surface treatment (plating) for the exposed portion and the outer layer circuit pattern.

Abstract: A method for producing a multilayer printed wiring board includes an inner layer formation step of forming an inner layer pattern in a core substrate divided corresponding to a flexible portion that is made bendable and a hard portion that is made rigid, and an outer layer formation step of forming an outer layer such that an outer layer material that covers the core substrate is caused to make contact at the hard portion, and an outer layer pattern formation step of forming an outer layer pattern in the surface of the outer layer material, and a removal step of removing a covering portion that is the outer layer material and is covering the flexible portion, and an outer shape formation step of forming the outer shape of a layered substrate formed via the removal step.