IP Library › Granted Patent US 4,980,089
Granted Patent Utility
US 4,980,089 · App. 07/378,945

Photochromic spiropyran compounds

Inventor: Harry G. Heller
Patented Case View Patent ↗
Granted: Dec 25, 1990 Filed: Jul 12, 1989
Inventor
Harry G. Heller
Assignee (at issue)
PPG Industries, Inc.

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Quick Facts
Patent No.
US 4,980,089
App. No.
07/378,945
Filed
1989-07-12
Granted
1990-12-25
Kind
A