Granted Patent
Utility
US 4,022,444 · App. 05/607,625
Apparatus for adding mischmetal to molten steel
Inventor:
Joseph R. Jackman
Patented Case
View Patent ↗
Granted: May 10, 1977
Filed: Aug 25, 1975
Inventor
Joseph R. Jackman
Assignee (at issue)
Reactive Metals & Alloys Corporation
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.