To provide a wiring circuit board which improves the adherence between conductor patterns and an insulating layer even if the conductor patterns are formed at a fine pitch, and prevents a plating liquid from remaining between a metal plating layer and the insulating layer to prevent ionic impurities from staying as a scum, so that short circuit due to ion migration is inhibited to reduce an insulation failure in the circuit board even if it is electrified for a long time under a condition of high temperature and humidity.
At longitudinal one end of the flexible wiring circuit board 1 exposed out of a cover insulating layer 4, respective lower ends of terminals 5 formed on a base insulating layer 2 and the lower end of each side face of the metal plating layer 6 coating each terminal 5 are buried in the base insulating layer 2. This prevents the plating liquid from soaking in between the base layer 2 and each lower end on completion of the metal plating layer 6.
MIYAKE YASUFUMI
OKAWA TADAO
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