Granted Patent
Utility
US 5,041,564 · App. 07/509,431
Vapor phase process for production of gamma-butyrolactone
Inventor:
Donald W. Buchanan, Jr.
Patented Case
View Patent ↗
Granted: Aug 20, 1991
Filed: Apr 16, 1990
Inventor
Donald W. Buchanan, Jr.
Assignee (at issue)
GAF Chemicals 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.