Granted Patent
Utility
US 5,189,075 · App. 07/838,990
Polyurea elastomers made using polyoxyalkylene tetra-or higher functional amine chain extenders
Inventors:
Robert L. Zimmerman, Dudley J. Primeaux, II
Patented Case
View Patent ↗
Granted: Feb 23, 1993
Filed: Feb 21, 1992
Inventors
Robert L. Zimmerman
Dudley J. Primeaux, II
Assignee (at issue)
Texaco Chemical 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.