IP Library › Granted Patent US 5,304,227
Granted Patent Utility
US 5,304,227 · App. 08/053,517

Electret filters

Inventors: Satoshi Matsuura, Tsuneo Kishiba, Yoshio Shinagawa
Patented Case View Patent ↗
Granted: Apr 19, 1994 Filed: Apr 28, 1993
Inventors
Satoshi Matsuura
Tsuneo Kishiba
Yoshio Shinagawa
Assignee (at issue)
Mitsui Petrochemical Industries, Ltd.

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Quick Facts
Patent No.
US 5,304,227
App. No.
08/053,517
Filed
1993-04-28
Granted
1994-04-19
Kind
A