Granted Patent
Utility
US 4,667,009 · App. 06/780,115
Polymethylene polyphenylamine modified diamine chain extenders in polyurea elastomers
Inventors:
James H. Ewen, John O. Guerrero
Patented Case
View Patent ↗
Granted: May 19, 1987
Filed: Sep 25, 1985
Inventors
James H. Ewen
John O. Guerrero
Assignee (at issue)
THE DOW CHEMICAL COMPANY
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.