Granted Patent
Utility
US 5,210,220 · App. 07/773,874
Method for preparing derivatives of ascorbic acid
Inventors:
Horst Pauling, Christof Wehrli
Patented Case
View Patent ↗
Granted: May 11, 1993
Filed: Oct 25, 1991
Inventors
Horst Pauling
Christof Wehrli
Assignee (at issue)
HOFFMANN-LA ROCHE INC.
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.