Granted Patent
Utility
US 4,599,445 · App. 06/652,922
Process for benzophenone tetracarboxylic acid
Inventor:
Visweswara R. Durvasula
Patented Case
View Patent ↗
Granted: Jul 8, 1986
Filed: Sep 21, 1984
Inventor
Visweswara R. Durvasula
Assignee (at issue)
THE DOW CHEMICAL 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.