IP Library › Granted Patent US 5,256,176
Granted Patent Utility
US 5,256,176 · App. 07/668,042

Film electret and an electret filter

Inventors: Satoshi Matsuura, Yoshio Shinagawa
Patented Case View Patent ↗
Granted: Oct 26, 1993 Filed: Mar 12, 1991
Inventors
Satoshi Matsuura
Yoshio Shinagawa
Assignee (at issue)
Mitsui Petrochemical Industries, Ltd.

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Quick Facts
Patent No.
US 5,256,176
App. No.
07/668,042
Filed
1991-03-12
Granted
1993-10-26
Kind
A