Granted Patent
Utility
US 4,902,831 · App. 07/118,126
Preparation of ethylenediamine derivatives
Inventors:
Khuong H. X. Mai, Ghanshyam Patil
Patented Case
View Patent ↗
Granted: Feb 20, 1990
Filed: Nov 9, 1987
Inventors
Khuong H. X. Mai
Ghanshyam Patil
Assignee (at issue)
E.I. DU PONT DE NEMOURS AND 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.