Granted Patent
Utility
US 4,368,922 · App. 06/212,215
Method for solution mining of complex carbonaceous materials
Inventors:
Adley W. Hemphill, Joseph T. Lundquist, Carl V. McDaniel
Patented Case
View Patent ↗
Granted: Jan 18, 1983
Filed: Dec 2, 1980
Inventors
Adley W. Hemphill
Joseph T. Lundquist
Carl V. McDaniel
Assignee (at issue)
W. R. Grace & Co.
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.