Granted Patent
Utility
US 4,298,586 · App. 06/177,558
Recovery of hydrofluoric acid from fluosilicic acid
Inventor:
Subhas K. Sikdar
Patented Case
View Patent ↗
Granted: Nov 3, 1981
Filed: Aug 23, 1980
Inventor
Subhas K. Sikdar
Assignee (at issue)
Occidental Research 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.