Granted Patent
Utility
US 4,153,441 · App. 05/930,036
Process for making magnesium potassium ammonium phosphate
Inventors:
William L. Guithues, Casimer C. Legal, Jr.
Patented Case
View Patent ↗
Granted: May 8, 1979
Filed: Aug 1, 1978
Inventors
William L. Guithues
Casimer C. Legal, Jr.
Assignee (at issue)
W. R. Grace & Co.
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.