Granted Patent
Utility
US 4,720,334 · App. 06/926,495
Diaphragm for electrolytic cell
Inventors:
Donald W. DuBois, William W. Carlin
Patented Case
View Patent ↗
Granted: Jan 19, 1988
Filed: Nov 4, 1986
Inventors
Donald W. DuBois
William W. Carlin
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.