Granted Patent
Utility
US 4,972,011 · App. 07/407,224
Flame retardant polymer composition containing phosphonic acid salts
Inventors:
Joyce Richardson, Richard J. Dellar
Patented Case
View Patent ↗
Granted: Nov 20, 1990
Filed: Sep 8, 1989
Inventors
Joyce Richardson
Richard J. Dellar
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.