Granted Patent
Utility
US 4,234,544 · App. 06/051,776
Liquid-liquid extraction apparatus
Inventor:
William J. Christman
Patented Case
View Patent ↗
Granted: Nov 18, 1980
Filed: Jun 25, 1979
Inventor
William J. Christman
Assignee (at issue)
UOP LLC
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.