Granted Patent
Utility
US 4,892,779 · App. 07/286,584
Multilayer article of microporous and substantially nonporous materials
Inventors:
Dennis D. Leatherman, Richard A. Schwarz
Patented Case
View Patent ↗
Granted: Jan 9, 1990
Filed: Dec 19, 1988
Inventors
Dennis D. Leatherman
Richard A. Schwarz
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.