Granted Patent
Utility
US 4,495,022 · App. 06/413,301
Extrusion method and apparatus
Inventors:
Montri Viriyayuthakorn, Robert V. DeBoo
Patented Case
View Patent ↗
Granted: Jan 22, 1985
Filed: Aug 31, 1982
Inventors
Montri Viriyayuthakorn
Robert V. DeBoo
Assignee (at issue)
AT&T Technologies Incorporated
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.