Granted Patent
Utility
US 5,258,274 · App. 07/887,778
Thermal dye bleach construction sensitive to ultraviolet radiation
Inventors:
Randall H. Helland, George V. D. Tiers, Dian E. Stevenson
Patented Case
View Patent ↗
Granted: Nov 2, 1993
Filed: May 22, 1992
Inventors
Randall H. Helland
George V. D. Tiers
Dian E. Stevenson
Assignee (at issue)
Minnesota Mining and Manufacturing Company
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.