Granted Patent
Utility
US 4,668,805 · App. 06/885,517
Chromones
Inventor:
Edwin S. C. Wu
Patented Case
View Patent ↗
Granted: May 26, 1987
Filed: Jul 14, 1986
Inventor
Edwin S. C. Wu
Assignee (at issue)
Pennwalt Corporation
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.