Granted Patent
Utility
US 4,234,718 · App. 06/053,611
Process for preparing cellulose acetate
Inventor:
David Brown
Patented Case
View Patent ↗
Granted: Nov 18, 1980
Filed: Jun 29, 1979
Inventor
David Brown
Assignee (at issue)
Halcon Research and Development Corp.
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.