US 12,267,952 B2
Flexible printed wiring board and method of manufacturing the same
Maki Ikebe, Osaka (JP); Koji Nitta, Osaka (JP); Shoichiro Sakai, Osaka (JP); Shingo Nagata, Osaka (JP); Junichi Motomura, Koka (JP); and Masahiro Itoh, Koka (JP)
Assigned to SUMITOMO ELECTRIC INDUSTRIES, LTD., Osaka (JP); and SUMITOMO ELECTRIC PRINTED CIRCUITS, INC., Koka (JP)
Appl. No. 17/791,931
Filed by SUMITOMO ELECTRIC INDUSTRIES, LTD., Osaka (JP); and SUMITOMO ELECTRIC PRINTED CIRCUITS, INC., Koka (JP)
PCT Filed Jun. 23, 2021, PCT No. PCT/JP2021/023701
§ 371(c)(1), (2) Date Jul. 11, 2022,
PCT Pub. No. WO2022/009675, PCT Pub. Date Jan. 13, 2022.
Claims priority of application No. 2020-117888 (JP), filed on Jul. 8, 2020.
Prior Publication US 2023/0050814 A1, Feb. 16, 2023
Int. Cl. H05K 1/02 (2006.01)
CPC H05K 1/0296 (2013.01) [H05K 1/028 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A flexible printed wiring board comprising a base film and a plurality of wiring lines disposed on a front surface of the base film,
wherein each of the wiring lines has a front end surface extending in a longitudinal direction of the wiring line and two side surfaces extending in the longitudinal direction, and the side surfaces have an arithmetical mean roughness Ra of 0.05 μm to 2.0 μm,
the wiring lines have an average height of 40 μm to 120 μm,
the wiring lines have an average spacing of 1 μm to 30 μm, and
wherein a width of each of the wiring lines increases from the front surface of the base film toward the front end surface in a section perpendicular to the longitudinal direction.