Granted Patent
Utility
US 4,471,070 · App. 06/445,130
Preparative process for alkaline earth metal, aluminum-containing spinels
Inventors:
Kristine S. Siefert, Jin S. Yoo, Emmett H. Burk, Jr.
Patented Case
View Patent ↗
Granted: Sep 11, 1984
Filed: Nov 29, 1982
Inventors
Kristine S. Siefert
Jin S. Yoo
Emmett H. Burk, Jr.
Assignee (at issue)
Atlantic Richfield Company
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.