Patent attributes
Stress concentration at the connecting portion of the electronic component and the curved board and the area around the connecting portion is suppressed. In a flexible wiring board, insulation layers (11, 13) and wiring layers (12, 15) are piled up alternately and wiring layers (12, 15) are via-connected each other. The board comprises reinforced area (10a) reinforced against external stress, bending area (10c) bending easier than the reinforced area (10a) by external stress, and a stress relaxation area (10b) provided in area between the reinforced area (10a) and the bending area (10c), bending easier than the reinforced area (10a) but not easier than the bending area (10c) by the external stress, and relaxing the stress carried from the bending area (10c) to the reinforced area (10a).