Granted Patent
Utility
US 5,688,969 · App. 08/751,566
Process for the preparation of thiophene-2-5-dicarboxylic acid and the dichloride thereof
Inventor:
Ivan Orban
Patented Case
View Patent ↗
Granted: Nov 18, 1997
Filed: Nov 18, 1996
Inventor
Ivan Orban
Assignee (at issue)
Ciba Specialty Chemicals Corporation
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.