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:
Oct. 12, 1976
Filed:
Sep. 10, 1975
Applicant:
Inventors:
Assignee:
Kureha Kagaku Kogyo Kabushiki Kaisha, Tokyo, JA;
Primary Examiner:
Int. Cl.
CPC ...
H01G / ;
U.S. Cl.
CPC ...
427 12 ; 29592 ; 1791 / ; 307 / ; 427100 ;
Abstract
For making a piezoelectric thermoplastic film device, a polar thermoplastic film is provided on both sides thereof with conductive layers which function as polarizing electrodes during the polarizing step. In a polarizing zone, a polarizing voltage is applied across the electrodes while the film is heated to a suitable polarizing temperature. To reduce undesirable capacitive effects, at least one electrode layer is separated into sections by narrow insulating regions extending transversely across the film. After cooling, the polarizing voltage and the accumulated electric charges in the film are removed.