US Patent 7772501 Flexible printed circuit board

A flexible printed circuit board (FPC) is disclosed which can eliminate the need for forming through holes and ensure the strength required for mounting components. The FPC has a metal foil layer formed only on one side of an insulating layer via an adhesive layer. The FPC is configured such that the insulating layer and the adhesive layer are partially removed, and the surface of the metal foil layer on the side from which the insulating layer and the adhesive layer have been removed is flattened. In a region from which the insulating layer and the adhesive layer have been removed, an overcoat layer for reinforcing the metal foil layer is provided along the metal foil layer on a surface opposite to the flattened surface. A drive IC is mounted on a first metal foil face of the metal foil layer and on a second metal foil face which is the flattened surface of the metal foil layer, and is provided with electrical conduction by the metal foil layer. To form the FPC, the insulating layer and the metal foil layer can be directly affixed to each other without using the adhesive layer.