Granted Patent
Utility
US 4,382,801 · App. 06/330,745
Process for spin dyeing polymers or copolymers of acrylonitrile with quaternized heterocyclic diazo dye and tetrafluoro-borate anion
Inventor:
Peter Loew
Patented Case
View Patent ↗
Granted: May 10, 1983
Filed: Dec 14, 1981
Inventor
Peter Loew
Assignee (at issue)
Ciba-Geigy
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.