Granted Patent
Utility
US 4,312,973 · App. 06/139,449
Polyurethane elastomers prepared from polyol or polymer/polyol-chain extender mixtures
Inventors:
Frank E. Critchfield, Richard M. Gerkin, Leslie E. Hawker
Patented Case
View Patent ↗
Granted: Jan 26, 1982
Filed: Apr 11, 1980
Inventors
Frank E. Critchfield
Richard M. Gerkin
Leslie E. Hawker
Assignee (at issue)
Union Carbide Corporation
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.