Granted Patent
Utility
US 4,279,879 · App. 06/080,485
Silica gel
Inventors:
Milton E. Winyall, Charles Davidoff
Patented Case
View Patent ↗
Granted: Jul 21, 1981
Filed: Oct 1, 1979
Inventors
Milton E. Winyall
Charles Davidoff
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.