Granted Patent
Utility
US 4,226,840 · App. 06/077,245
Process for the polymerization of cyclic polyhalophosphazenes using a catalyst composition of boron trihalide and oxygenated phosphorus compounds
Inventors:
John W. Fieldhouse, Daniel F. Graves
Patented Case
View Patent ↗
Granted: Oct 7, 1980
Filed: Sep 19, 1979
Inventors
John W. Fieldhouse
Daniel F. Graves
Assignee (at issue)
The Firestone Tire & Rubber Company
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.