Granted Patent
Utility
US 4,645,839 · App. 06/725,680
Sulphur dehydrogenation process to yield 5-methyl-2-pyridone
Inventors:
Walter M. Kruse, John F. Stephen
Patented Case
View Patent ↗
Granted: Feb 24, 1987
Filed: Apr 22, 1985
Inventors
Walter M. Kruse
John F. Stephen
Assignee (at issue)
ICI Americas, Inc.
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.