Granted Patent
Utility
US 4,468,868 · App. 06/393,960
Gas-solid counterflow vessel
Inventors:
Lee R. Mull, Mark A. Propster
Patented Case
View Patent ↗
Granted: Sep 4, 1984
Filed: Jun 30, 1982
Inventors
Lee R. Mull
Mark A. Propster
Assignee (at issue)
Owens-Corning Fiberglas Corp.
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.