Granted Patent
Utility
US 4,372,834 · App. 06/275,426
Purification process for compounds useful in optical fiber manufacture
Inventors:
Robert L. Barns, Edwin Arthur Chandross, Daniel Flamm, Louis Thomas Manzione, Larry F. Thompson
Patented Case
View Patent ↗
Granted: Feb 8, 1983
Filed: Jun 19, 1981
Inventors
Robert L. Barns
Edwin Arthur Chandross
Daniel Flamm
Louis Thomas Manzione
Larry F. Thompson
Assignee (at issue)
Bell Telephone Laboratories, 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.