IP Library › Granted Patent US 4,049,567
Granted Patent Utility
US 4,049,567 · App. 05/667,686

Silver halide activated photochromic plastics

Inventors: Nori Y. C. Chu, Peter G. Piusz
Patented Case View Patent ↗
Granted: Sep 20, 1977 Filed: Mar 17, 1976
Inventors
Nori Y. C. Chu
Peter G. Piusz
Assignee (at issue)
American Optical Corporation

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Quick Facts
Patent No.
US 4,049,567
App. No.
05/667,686
Filed
1976-03-17
Granted
1977-09-20
Kind
A