Granted Patent
Utility
US 5,260,403 · App. 07/906,887
Color-developing composition, aqueous suspension of the composition, and color-developing sheet produced using the suspension and suitable for use in pressure-sensitive copying paper
Inventors:
Keizaburo Yamaguchi, Yoshimitsu Tanabe, Kiyoharu Hasegawa, Akihiro Yamaguchi
Patented Case
View Patent ↗
Granted: Nov 9, 1993
Filed: Jul 2, 1992
Inventors
Keizaburo Yamaguchi
Yoshimitsu Tanabe
Kiyoharu Hasegawa
Akihiro Yamaguchi
Assignee (at issue)
Mitsui Toatsu Chemicals, Incorporated
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.