Granted Patent
Utility
US 4,879,021 · App. 07/237,636
Hydrogenation of coal and subsequent liquefaction of hydrogenated undissolved coal
Inventors:
Edwin J. Hippo, Alfred G. Comolli, Robert O'Brien
Patented Case
View Patent ↗
Granted: Nov 7, 1989
Filed: Aug 26, 1988
Inventors
Edwin J. Hippo
Alfred G. Comolli
Robert O'Brien
Assignee (at issue)
HRI
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.