Granted Patent
Utility
US 4,895,977 · App. 07/283,112
Purification of alkanesulfonic acids using ozone
Inventor:
Martin Nosowitz
Patented Case
View Patent ↗
Granted: Jan 23, 1990
Filed: Dec 12, 1988
Inventor
Martin Nosowitz
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.