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. 26, 1982
Filed:
Mar. 10, 1981
Applicant:
Inventors:
Sakae Tamura, Yokohama, JP;
Hiromi Yoshida, Akatsuka Shinmachi, JP;
Takehiko Kotoh, Sagamihara, JP;
Masami Kobayashi, Tokyo, JP;
Assignee:
Tokyo Shibaura Denki Kabushiki Kaisha, Kawasaki, JP;
Primary Examiner:
Int. Cl.
CPC ...
B32B / ; H04R / ;
U.S. Cl.
CPC ...
156220 ; 2959 / ; 156196 ; 1791 / ; 428156 ;
Abstract
A method of manufacturing an electret device which comprises the step of causing a pressure deformation jig whose surface is provided with numerous minute convex and concave regions to abut against the surface of a raw dielectric material for an electret and later be removed therefrom, thereby forming minute stretched and contracted region on the surface of said dielectric material.