Granted Patent
Utility
US 5,147,622 · App. 07/665,511
Method for stabilizing phosphorus trichloride
Inventor:
Rudolf Schumann
Patented Case
View Patent ↗
Granted: Sep 15, 1992
Filed: Mar 6, 1991
Inventor
Rudolf Schumann
Assignee (at issue)
Chemie AG Bitterfeld-Wolfen
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.