Granted Patent
Utility
US 4,325,844 · App. 06/151,561
Method of preparing diatomite for rapid calcination
Inventor:
Bruce C. Olmsted, Jr.
Patented Case
View Patent ↗
Granted: Apr 20, 1982
Filed: May 20, 1980
Inventor
Bruce C. Olmsted, Jr.
Assignee (at issue)
Manville Service 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.