Granted Patent
Utility
US 3,957,689 · App. 05/494,247
Process for preparing an attrition resistant zeolite hydrocarbon conversion catalyst
Inventors:
John J. Ostermaier, Curtis Elliott
Patented Case
View Patent ↗
Granted: May 18, 1976
Filed: Aug 2, 1974
Inventors
John J. Ostermaier
Curtis Elliott
Assignee (at issue)
W. R. Grace & Co.
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.