Granted Patent
Utility
US 4,213,752 · App. 05/958,308
Coal drying process
Inventor:
Walter H. Seitzer
Patented Case
View Patent ↗
Granted: Jul 22, 1980
Filed: Nov 6, 1978
Inventor
Walter H. Seitzer
Assignee (at issue)
SUNTEC CO., LTD.
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.