IP Library › Granted Patent US 4,220,708
Granted Patent Utility
US 4,220,708 · App. 05/846,148

Photochromic compounds

Inventor: Harold G. Heller
Patented Case View Patent ↗
Granted: Sep 2, 1980 Filed: Oct 27, 1977
Inventor
Harold G. Heller

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Quick Facts
Patent No.
US 4,220,708
App. No.
05/846,148
Filed
1977-10-27
Granted
1980-09-02
Kind
A