Granted Patent
Utility
US 5,218,127 · App. 07/972,407
Method of preparing mono (indolylethylenyl) phthalides
Inventor:
Ponnampalam Mathiaparanam
Patented Case
View Patent ↗
Granted: Jun 8, 1993
Filed: Nov 6, 1992
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.