Granted Patent
Utility
US 4,384,920 · App. 06/407,203
Method and apparatus for oxygen delignification
Inventors:
Larry D. Markham, Edward F. Elton, Vincent L. Magnotta
Patented Case
View Patent ↗
Granted: May 24, 1983
Filed: Aug 11, 1982
Inventors
Larry D. Markham
Edward F. Elton
Vincent L. Magnotta
Assignees (at issue)
Black Clawson Company, Inc.
Air Products and Chemicals, 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.