Granted Patent
Utility
US 5,039,821 · App. 07/561,839
Process for producing di[bis-(indolyl)ethylenyl]tetrahalophthalides
Inventor:
Ponnampalam Mathiaparanam
Patented Case
View Patent ↗
Granted: Aug 13, 1991
Filed: Aug 2, 1990
Inventor
Ponnampalam Mathiaparanam
Assignee (at issue)
Appleton Papers Inc.
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.