Granted Patent
Utility
US 4,477,423 · App. 06/489,478
Zeolite Y
Inventor:
Robert N. Sanders
Patented Case
View Patent ↗
Granted: Oct 16, 1984
Filed: Apr 28, 1983
Inventor
Robert N. Sanders
Assignee (at issue)
Ethyl Corporation
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.