Granted Patent
Utility
US 4,734,218 · App. 06/889,932
Dichroic azo dyestuffs and liquid crystal composition containing said dyestuffs
Inventors:
Keisuke Takuma, Kimitoshi Kato, Hiroshi Aiga, Yasuyuki Yamada, Tsutomu Nishizawa
Patented Case
View Patent ↗
Granted: Mar 29, 1988
Filed: Jul 18, 1986
Inventors
Keisuke Takuma
Kimitoshi Kato
Hiroshi Aiga
Yasuyuki Yamada
Tsutomu Nishizawa
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.