Granted Patent
Utility
US 4,704,259 · App. 06/866,726
Removal of chromium from cell liquor
Inventor:
Marek Lipsztajn
Patented Case
View Patent ↗
Granted: Nov 3, 1987
Filed: May 27, 1986
Inventor
Marek Lipsztajn
Assignee (at issue)
Tenneco Canada 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.