Granted Patent
Utility
US 4,565,621 · App. 06/569,238
Hydrocracking with rare earth-containing Y zeolite compositions
Inventor:
John W. Ward
Patented Case
View Patent ↗
Granted: Jan 21, 1986
Filed: Jan 9, 1984
Inventor
John W. Ward
Assignee (at issue)
Union Oil Company of California
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.