Granted Patent
Utility
US 4,489,106 · App. 06/427,398
Two step interleaving method
Inventors:
Paul F. Duffer, Helmut Franz, Joseph D. Kelly
Patented Case
View Patent ↗
Granted: Dec 18, 1984
Filed: Sep 29, 1982
Inventors
Paul F. Duffer
Helmut Franz
Joseph D. Kelly
Assignee (at issue)
PPG Industries, Inc.
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.