Granted Patent
Utility
US 4,833,172 · App. 07/244,980
Stretched microporous material
Inventors:
Richard A. Schwarz, Thomas Leigh, Dennis D. Leatherman
Patented Case
View Patent ↗
Granted: May 23, 1989
Filed: Sep 15, 1988
Inventors
Richard A. Schwarz
Thomas Leigh
Dennis D. Leatherman
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.