Granted Patent
Utility
US 4,606,879 · App. 06/706,517
High stalk blown film extrusion apparatus and method
Inventor:
Frank D. Cerisano
Patented Case
View Patent ↗
Granted: Aug 19, 1986
Filed: Feb 28, 1985
Inventor
Frank D. Cerisano
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.