| 摘要 |
PURPOSE:To obtain a film which can be curved freely in an optional direction and is easy to work by joining plastic films each consisting of an electromechanical converting material exhibiting a piezoelectric phenomenon in the polarization directions opposite from each other and impressing a voltage between both electrodes. CONSTITUTION:Polyvinylidene fluoride which is an electromechanical converting material of plastics is crystalline and behaves as a dielectric high polymer. The film consisting of said material exhibits a strong piezoelectric phenomenon. A joined film 1 of such polyvinylidene fluoride is formed by joining two sheets of films 2, 3 of which the polarization directions are opposite from each other in the thickness direction and adjusting the thickness thereof to a size (t). Electrodes 3, 4 are provided to both surfaces. When a voltage is impressed between the electrodes 3 and 4, the film 1 curves. When the direction of the voltage is changed, the film 1 curves in the opposite direction. |
