Flexible printed board and flexible printed board connection structure
Provided is a flexible printed board including: an insulating base material; a plurality of first wiring lines disposed on a front surface side of the base material; a plurality of first terminals each provided on an external connection side, of a respective one of the plurality of first wiring lines; a plurality of second wiring lines disposed on a rear surface side of the base material; and a plurality of second terminals each provided on an external connection side, of a respective one of the plurality of second wiring lines; in which: a restraining space for restraining surface flashover is provided from a first outermost terminal, which is outermost of the plurality of first terminals, through an edge portion of the base material, to a second outermost terminal, which is outermost of the plurality of second terminals.
1 . A flexible printed board comprising:
an insulating base material;
a plurality of first wiring lines disposed on a front surface side of the insulating base material, the plurality of first wiring lines being arranged in a length direction of the insulating base material and the plurality of first wiring lines extending in a width direction of the insulating base material;
a plurality of first terminals disposed on the front surface side, each of the plurality of first terminals provided on an external connection side, of a respective one of the plurality of first wiring lines;
a plurality of second wiring lines disposed on a rear surface side of the insulating base material, the plurality of second wiring lines being arranged in the length direction of the insulating base material and the plurality of second wiring lines extending in the width direction of the insulating base material;
a plurality of second terminals disposed on the rear surface side, each of the plurality of second terminals provided on an external connection side, of a respective one of the plurality of second wiring lines; and
a connection member including a conductive adhesive layer and a plurality of connection terminals electrically connected to the plurality of first terminals and the plurality of second terminals via the conductive adhesive layer, wherein the insulating base material includes a restraining space at each end of the insulating base material in the width direction of the insulating base material, which is outside of a first outermost terminal among the plurality of first terminals in the length direction and outside of a second outermost terminal among the plurality of second terminals length direction, the restraining space configured to restrain surface flashover of electrical discharge occurring between the first outermost terminal via a first outflow portion of the conductive adhesive layer between the connection member and the first outermost terminal and the second outermost terminal via a second outflow portion of the conductive adhesive layer between the connection member and the second outermost terminal around a side surface of an edge of the insulating base material.
2 . The flexible printed board according to claim 1 , wherein the restraining space is 2 mm or more in the width direction of the insulating base material.
3 . The flexible printed board according to claim 1 , further comprising:
an insulating projecting portion,
wherein the plurality of first wiring lines are at least partially covered with a first insulating layer,
the plurality of second wiring lines are at least partially covered with a second insulating layer, and
the insulating projecting portion is provided on at least one of an end portion side of the first insulating layer in the length direction of the plurality of first terminals or an end portion side of the second insulating layer in the length direction of the plurality of second terminals so as to project toward the external connection side.
4 . The flexible printed board according to claim 1 further comprising:
a first dummy terminal and a second dummy terminal,
wherein the first dummy terminal is provided outside the first outermost terminal of the plurality of first terminals in the length direction so as to extend toward the external connection side, and
the second dummy terminal is provided outside the second outermost terminal of the plurality of second terminals in the length direction so as to extend toward the external connection side.
5 . The flexible printed board according to claim 1 , wherein the plurality of first terminals and the plurality of second terminals are provided in mirror symmetry with the insulating base material interposed therebetween.
6 . The flexible printed board according to claim 1 ,
wherein the conductive adhesive layer includes an anisotropic conductive adhesive layer,
the anisotropic conductive adhesive layer includes an adhesive and conductive particles, and
the plurality of connection terminals are electrically connected to the plurality of first terminals or the plurality of second terminals via the conductive particles, and adjacent ones of the plurality of first terminals or adjacent ones of the plurality of second terminals are electrically insulated from each other via the adhesive.