Granted Patent
Utility
US 4,894,358 · App. 07/238,476
Thermal imaging with ylide dyes
Inventors:
Michael P. Filosa, Stephen Robert Herchen, Cheryl P. Petersen
Patented Case
View Patent ↗
Granted: Jan 16, 1990
Filed: Aug 31, 1988
Inventors
Michael P. Filosa
Stephen Robert Herchen
Cheryl P. Petersen
Assignee (at issue)
Polaroid 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.