Granted Patent
Utility
US 4,315,518 · App. 06/164,656
Methods of and system for controlling copper concentration in a solution
Inventor:
Ernest W. Sawyer
Patented Case
View Patent ↗
Granted: Feb 16, 1982
Filed: Jun 30, 1980
Inventor
Ernest W. Sawyer
Assignee (at issue)
Western Electric Company, 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.