Granted Patent
Utility
US 6,299,939 · App. 09/560,599
Method of preparing a diaphragm for an electrolytic cell
Inventors:
Donald W. DuBois, Bernard A. Maloney
Patented Case
View Patent ↗
Granted: Oct 9, 2001
Filed: Apr 28, 2000
Inventors
Donald W. DuBois
Bernard A. Maloney
Assignee (at issue)
PPG Industries Ohio, 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.