Granted Patent
Utility
US 4,956,009 · App. 07/456,530
Calcium alloy steel additive and method thereof
Inventor:
James W. Robison
Patented Case
View Patent ↗
Granted: Sep 11, 1990
Filed: Dec 26, 1989
Inventor
James W. Robison
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.