Granted Patent
Utility
US 4,584,420 · App. 06/623,897
Method for producing vinyl chloride
Inventors:
Charles R. Wiedrich, John C. Crano
Patented Case
View Patent ↗
Granted: Apr 22, 1986
Filed: Jun 25, 1984
Inventors
Charles R. Wiedrich
John C. Crano
Assignee (at issue)
PPG Industries, 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.