Granted Patent
Utility
US 4,226,639 · App. 06/042,479
Silica guard bed for adsorbent used in an aqueous system
Inventors:
Edward Michalko, Armand J. deRosset
Patented Case
View Patent ↗
Granted: Oct 7, 1980
Filed: May 25, 1979
Inventors
Edward Michalko
Armand J. deRosset
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.