Granted Patent
Utility
US 5,972,174 · App. 09/006,132
Process for the purification of maleic anhydride
Inventors:
Henry C. Brown, William H. Alumbaugh, Joseph C. Burnett
Patented Case
View Patent ↗
Granted: Oct 26, 1999
Filed: Jan 13, 1998
Inventors
Henry C. Brown
William H. Alumbaugh
Joseph C. Burnett
Assignee (at issue)
HUNTSMAN PETROCHEMICAL LLC
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.