Granted Patent
Utility
US 4,765,939 · App. 06/917,806
Process for preparing ultrathin polymethylmethacrylate polymer films
Inventor:
Rachel S. Kohn
Patented Case
View Patent ↗
Granted: Aug 23, 1988
Filed: Oct 10, 1986
Inventor
Rachel S. Kohn
Assignee (at issue)
Hoechst Celanese Corporation
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.