| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an electret sheet maintaining high piezoelectricity even when used at high temperature.SOLUTION: The electret sheet is manufactured by injecting an electrical charge into a polyether imide resin sheet containing a polyether imide resin having a repeating unit represented by the formula (I) to electrify the polyether imide resin sheet. When an external force is added to the electret sheet, it generates good electric response and has excellent piezoelectricity.</p> |
