Granted Patent
Utility
US 5,196,262 · App. 07/596,175
Microporous material
Inventors:
Richard A. Schwarz, William Keim
Patented Case
View Patent ↗
Granted: Mar 23, 1993
Filed: Oct 10, 1990
Inventors
Richard A. Schwarz
William Keim
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.