Granted Patent
Utility
US 4,253,990 · App. 06/074,284
Preparation method for catalyst supports and materials produced thereby
Inventor:
Stephen E. Gross
Patented Case
View Patent ↗
Granted: Mar 3, 1981
Filed: Sep 11, 1979
Inventor
Stephen E. Gross
Assignee (at issue)
Johns Manville
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.