Granted Patent
Utility
US 4,431,480 · App. 06/315,672
Method and apparatus for controlled addition of alkaline chemicals to an oxygen delignification reaction
Inventors:
Larry D. Markham, Vincent L. Magnotta
Patented Case
View Patent ↗
Granted: Feb 14, 1984
Filed: Oct 27, 1981
Inventors
Larry D. Markham
Vincent L. Magnotta
Assignee (at issue)
Black Clawson Company, Inc.
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.