Granted Patent
Utility
US 4,299,743 · App. 06/153,385
Sulfonate-containing polymer
Inventors:
Percy E. Pierce, Karl F. Schimmel
Patented Case
View Patent ↗
Granted: Nov 10, 1981
Filed: May 27, 1980
Inventors
Percy E. Pierce
Karl F. Schimmel
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.