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Patent Searching and Data


Title:
CHROMENE COMPOUND
Document Type and Number:
WIPO Patent Application WO/2002/090342
Kind Code:
A1
Abstract:
A chromene compound which typically is that represented by the following formula. (1) This chromene compound in a colored state has two absorption bands in the wavelength regions of from 440 to 500 nm and from 570 to 630 nm, wherein the difference in absorption intensity between the two absorption bands is small. The ratio of the intensity of developed-color density in one absorption band to that in the other is generally from 0.7 to 1.2. The chromene compound, even when used alone, can develop an intermediate color tone such as gray or brown.

Inventors:
IZUMI SHINOBU (JP)
NAGOH HIRONOBU (JP)
Application Number:
PCT/JP2002/004362
Publication Date:
November 14, 2002
Filing Date:
May 01, 2002
Export Citation:
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Assignee:
TOKUYAMA CORP (JP)
IZUMI SHINOBU (JP)
NAGOH HIRONOBU (JP)
International Classes:
C07D311/78; C07D311/94; C07D311/96; C07D405/10; C07D409/04; C07D455/04; C07D491/04; C07D491/052; C07D491/14; C07D493/04; C07D495/04; G03C1/685; G02B5/23; (IPC1-7): C07D311/78; C07D409/04; C07D491/052; C07D493/04; C07D495/04; G02B5/23; G02C7/10; G03C1/73
Domestic Patent References:
WO2000015628A12000-03-23
WO2000077007A12000-12-21
WO2002030916A12002-04-18
WO2002022594A12002-03-21
Foreign References:
JP2001114775A2001-04-24
Other References:
See also references of EP 1394156A4
Attorney, Agent or Firm:
Suzuki, Ikuo (Atago 1-chome Minato-ku, Tokyo, JP)
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