Granted Patent
Utility
US 4,531,139 · App. 06/544,422
Color developers for pressure-sensitive or heat-sensitive recording papers
Inventor:
Michael Seitz
Patented Case
View Patent ↗
Granted: Jul 23, 1985
Filed: Oct 21, 1983
Inventor
Michael Seitz
Assignee (at issue)
Standard Register, 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.