Granted Patent
Utility
US 5,120,799 · App. 07/405,875
Polymeric compounds having pendant sulphonato groups and method of producing the polymeric compounds
Inventors:
John R. Wade, Robert Alexander Walker Johnstone
Patented Case
View Patent ↗
Granted: Jun 9, 1992
Filed: Aug 30, 1989
Inventors
John R. Wade
Robert Alexander Walker Johnstone
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.