Granted Patent
Utility
US 5,493,013 · App. 08/252,386
Process for preparing cellulose ethers with cyclic ethers as suspending agents
Inventor:
Diethart Reichel
Patented Case
View Patent ↗
Granted: Feb 20, 1996
Filed: Jun 1, 1994
Inventor
Diethart Reichel
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.