Granted Patent
Utility
US 4,250,058 · App. 06/039,975
Method of preparing spheroidal alumina particles
Inventor:
Edward Michalko
Patented Case
View Patent ↗
Granted: Feb 10, 1981
Filed: May 17, 1979
Inventor
Edward Michalko
Assignee (at issue)
UOP LLC
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.