Granted Patent
Utility
US 4,683,039 · App. 06/813,078
Membrane pervaporation process
Inventors:
Zbigniew Twardowski, James D. McGilvery
Patented Case
View Patent ↗
Granted: Jul 28, 1987
Filed: Dec 24, 1985
Inventors
Zbigniew Twardowski
James D. McGilvery
Assignee (at issue)
Tenneco Canada Inc. (ERCO division)
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.