IP Library › Granted Patent US 4,909,963
Granted Patent Utility
US 4,909,963 · App. 07/280,604

Photochromic article

Inventors: Won S. Kwak, Chin-Wen Chen
Patented Case View Patent ↗
Granted: Mar 20, 1990 Filed: Dec 6, 1988
Inventors
Won S. Kwak
Chin-Wen Chen
Assignee (at issue)
PPG Industries, Inc.

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Quick Facts
Patent No.
US 4,909,963
App. No.
07/280,604
Filed
1988-12-06
Granted
1990-03-20
Kind
A