Abstract: Provided is a novel piezoelectric element that has a generally long linear shape and has excellent flexibility and bend resistance. The piezoelectric element includes a core wire which is a resin wire having at least one layer of metal foil helically wound therearound, an organic piezoelectric layer that coats the core wire, and a conductor layer that coats the organic piezoelectric layer. The metal foil and the conductor layer each function as an electrode having the organic piezoelectric layer interposed therebetween. The at least one layer of metal foil is helically wound around the resin wire with gaps, and the ratio of the gap to the helical pitch of the metal foil is 0.4% to 50%.

Abstract: Provided is a novel piezoelectric element that has a generally long linear shape and has excellent flexibility and bend resistance. The piezoelectric element includes a core wire which is a resin wire having at least one layer of metal foil helically wound therearound, an organic piezoelectric layer that coats the core wire, and a conductor layer that coats the organic piezoelectric layer. The metal foil and the conductor layer each function as an electrode having the organic piezoelectric layer interposed therebetween. The at least one layer of metal foil is helically wound around the resin wire with gaps, and the ratio of the gap to the helical pitch of the metal foil is 0.4% to 50%.

Abstract: A piezoelectric wire of the present invention includes a conductive wire 11 and a polymer piezoelectric layer 12 that coats the conductive wire 11. The polymer piezoelectric layer 12 contains a ?-phase polyvinylidene fluoride-based copolymer, and the conductive wire 11 has a wire diameter of 1.0 mm or less. The ?-phase polyvinylidene fluoride-based copolymer is preferably at least one selected from a vinylidene fluoride-trifluoroethylene copolymer and a vinylidene fluoride-tetrafluoroethylene copolymer.