Granted Patent
Utility
US 5,318,856 · App. 07/996,814
Water-soluble azo dyes and polarizing films using the dyes
Inventors:
Tsutami Misawa, Akira Ogiso, Rihoko Imai, Hisato Itoh
Patented Case
View Patent ↗
Granted: Jun 7, 1994
Filed: Dec 24, 1992
Inventors
Tsutami Misawa
Akira Ogiso
Rihoko Imai
Hisato Itoh
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.