Granted Patent
Utility
US 4,473,509 · App. 06/442,103
Process for making phosphonic anhydrides
Inventors:
Jurgen Grosse, Werner Pieper
Patented Case
View Patent ↗
Granted: Sep 25, 1984
Filed: Nov 16, 1982
Inventors
Jurgen Grosse
Werner Pieper
Assignee (at issue)
Hoechst GmbH
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.