IP Library › Granted Patent US 4,997,903
Granted Patent Utility
US 4,997,903 · App. 07/231,151

Polycarbonate-made optical article

Inventor: Masaya Okamoto
Patented Case View Patent ↗
Granted: Mar 5, 1991 Filed: Aug 11, 1988
Inventor
Masaya Okamoto
Assignee (at issue)
Idemitsu Petrochemical Co., Ltd.

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Quick Facts
Patent No.
US 4,997,903
App. No.
07/231,151
Filed
1988-08-11
Granted
1991-03-05
Kind
A