Granted Patent
Utility
US 6,509,409 · App. 09/674,272
Polyurethane dispersants
Inventor:
Dean Thetford
Patented Case
View Patent ↗
Granted: Jan 21, 2003
Filed: Oct 30, 2000
Inventor
Dean Thetford
Assignee (at issue)
Avecia Limited
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.