Granted Patent
Utility
US 4,253,989 · App. 05/896,318
Zeolitic catalyst and method of producing same
Inventors:
John Lim, Ralph Haney
Patented Case
View Patent ↗
Granted: Mar 3, 1981
Filed: Apr 14, 1978
Inventors
John Lim
Ralph Haney
Assignee (at issue)
Filtrol 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.