Granted Patent
Utility
US 4,779,657 · App. 07/137,979
Rubber compositions
Inventors:
Seung T. Cheung, Richard Samuel Steevensz
Patented Case
View Patent ↗
Granted: Oct 25, 1988
Filed: Dec 28, 1987
Inventors
Seung T. Cheung
Richard Samuel Steevensz
Assignee (at issue)
Polytec GmbH
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.