Granted Patent
Utility
US 5,342,974 · App. 07/291,028
Halogenated anthraquinone and their use as near infrared rays absorbing optical filters
Inventors:
Tsukasa Ohyama, Shizuo Kuroda, Keisuke Takuma, Hiroshi Aiga
Patented Case
View Patent ↗
Granted: Aug 30, 1994
Filed: Dec 28, 1988
Inventors
Tsukasa Ohyama
Shizuo Kuroda
Keisuke Takuma
Hiroshi Aiga
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.