Granted Patent
Utility
US 5,228,979 · App. 07/803,141
Hydrocracking with a catalyst containing a noble metal and zeolite beta
Inventor:
John W. Ward
Patented Case
View Patent ↗
Granted: Jul 20, 1993
Filed: Dec 5, 1991
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.