Patent ID: 11950365
Assignee: SUMITOMO ELECTRIC PRINTED CIRCUITS, INC.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H  C | IPC H

Claim 0:
1. A flexible printed circuit board comprising:
a base film having a hole for forming a through hole; and
a coil-shaped wiring layer layered on at least one surface side of the base film,
wherein the wiring layer includes a land portion arranged at an inner peripheral surface of the hole and at a peripheral portion of the hole of the base film, and a winding portion arranged in a spiral shape with the land portion as an inside end portion or an outside end portion,
wherein the winding portion includes a first winding portion that is an outermost circumference and a second winding portion that is inside relative to the outermost circumference,
wherein a ratio of an average thickness of the land portion to an average thickness of the second winding portion is 1.1 or more and 5 or less, and
wherein the average thickness of the land portion is greater than or equal to 20 μm.