Granted Patent
Utility
US 4,483,803 · App. 06/429,925
Preparation of carboxylic acid anhydrides
Inventor:
Nabil Rizkalla
Patented Case
View Patent ↗
Granted: Nov 20, 1984
Filed: Sep 30, 1982
Inventor
Nabil Rizkalla
Assignee (at issue)
The Halcon SD Group, 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.