Patent ID: 10535811

Abstract:
A piezoelectric film which is better in heat and deformation resistant properties than those in the prior art is provided along with a method of manufacture. The film is a piezoelectric film that is composed of a copolymer of vinylidene fluoride and trifluoroethylene, the copolymer having a content of vinylidene fluoride in a range of not less than 82 mol % and not more than 86 mol % and having a molecular weight not less than 600,000. The piezoelectric film is subjected to a heat treatment for crystallization of the copolymer at a temperature ranging from not less than 140° C. to not more than 150° C., and is thereby caused to develop piezoelectric property. The piezoelectric film further has a heat resistance of not less than 140° C. and a breaking distortion of not less than 8% and not more than 55%, and an excellent deformation resistant property.