IP Library › Granted Patent US 5,143,767
Granted Patent Utility
US 5,143,767 · App. 07/296,000

Processes for preparing electret filters

Inventors: Satoshi Matsuura, Masayuki Mito, Yoshio Shinagawa
Patented Case View Patent ↗
Granted: Sep 1, 1992 Filed: Jan 12, 1989
Inventors
Satoshi Matsuura
Masayuki Mito
Yoshio Shinagawa
Assignee (at issue)
Mitsui Petrochemical Industries, Ltd.

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Quick Facts
Patent No.
US 5,143,767
App. No.
07/296,000
Filed
1989-01-12
Granted
1992-09-01
Kind
A