Granted Patent
Utility
US 4,711,401 · App. 07/004,356
Method of grinding a hydraulic cement
Inventor:
Frank G. Serafin
Patented Case
View Patent ↗
Granted: Dec 8, 1987
Filed: Jan 16, 1987
Inventor
Frank G. Serafin
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.