Granted Patent
Utility
US 4,581,111 · App. 06/594,183
Treatment of ultrafiltrate by electrodialysis
Inventors:
Roger M. Christenson, Donald D. Emmonds, Matthew S. Scott
Patented Case
View Patent ↗
Granted: Apr 8, 1986
Filed: Mar 28, 1984
Inventors
Roger M. Christenson
Donald D. Emmonds
Matthew S. Scott
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.