Granted Patent
Utility
US 4,985,141 · App. 07/323,858
Liquid-liquid contactor columns
Inventors:
Douglas E. Parker, Dennis H. Logsdail
Patented Case
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Granted: Jan 15, 1991
Filed: Mar 15, 1989
Inventors
Douglas E. Parker
Dennis H. Logsdail
Assignee (at issue)
The Secretary of State for United Kingdom Atomic Energy Authority in Her Britannic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland
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.