Granted Patent
Utility
US 4,944,972 · App. 07/140,096
Coextrusion apparatus, methods, and related films and packages
Inventor:
Robert J. Blembereg
Patented Case
View Patent ↗
Granted: Jul 31, 1990
Filed: Dec 31, 1987
Inventor
Robert J. Blembereg
Assignee (at issue)
American National Can 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.