Granted Patent
Utility
US 5,731,112 · App. 08/652,144
Processless diacetylenic salt films capable of developing a black image
Inventors:
David F. Lewis, Sangya S. Varma
Patented Case
View Patent ↗
Granted: Mar 24, 1998
Filed: May 23, 1996
Inventors
David F. Lewis
Sangya S. Varma
Assignee (at issue)
ISP INVESTMENTS 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.