Granted Patent
Utility
US 4,642,397 · App. 06/782,674
Process for separating isomers of dinitrotoluene
Inventors:
Hermann A. Zinnen, Thad S. Franczyk
Patented Case
View Patent ↗
Granted: Feb 10, 1987
Filed: Oct 1, 1985
Inventors
Hermann A. Zinnen
Thad S. Franczyk
Assignee (at issue)
UOP LLC
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.