Granted Patent
Utility
US 6,706,897 · App. 10/373,430
Method for preparing oxydiphthalic anhydrides using guanidinium salt as catalyst
Inventors:
Daniel J. Brunelle, Qing Ye
Patented Case
View Patent ↗
Granted: Mar 16, 2004
Filed: Feb 24, 2003
Inventors
Daniel J. Brunelle
Qing Ye
Assignee (at issue)
General Electric 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.