The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 29, 2014
Filed:
Apr. 12, 2012
Kazuho Uchida, Shimamoto-cho, JP;
Takazumi Okabayashi, Shimamoto-cho, JP;
Yoshiro Tajitsu, Suita-shi, JP;
Kazuho Uchida, Shimamoto-cho, JP;
Takazumi Okabayashi, Shimamoto-cho, JP;
Yoshiro Tajitsu, Suita-shi, JP;
Sekisui Chemical Co., Ltd., Osaka, JP;
A School Corporation Kansai University, Osaka, JP;
Abstract
Provided is an electret having high piezoelectric properties. An electret sheet of the invention is characterized in that it comprises a synthetic resin sheet is electrified by injecting electric charges thereinto, that the synthetic resin sheet comprises two types of synthetic resins incompatible with each other, and that these synthetic resins form a phase separated structure and are cross-linked through a polyfunctional monomer. Therefore, positive and negative charges in an apparently polarized state are present in the interfacial portions between the two types of synthetic resins incompatible with each other. By applying an external force to the electret sheet to deform it, the relative positions of these positive and negative charges are changed, and these changes cause a favorable electrical response. Therefore, the electret sheet has high piezoelectric properties.