Granted Patent
Utility
US 4,269,871 · App. 06/164,442
Antilumping expandable styrene polymers
Inventors:
Elizabeth A. Blommers, William J. Poole, Alvin R. Ingram
Patented Case
View Patent ↗
Granted: May 26, 1981
Filed: Jun 30, 1980
Inventors
Elizabeth A. Blommers
William J. Poole
Alvin R. Ingram
Assignee (at issue)
Arco Polymers, 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.