| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an infrared dye composition having excellent gray balance in the visible light region, an infrared ray absorbing ink using the same and an electrophotographic toner. <P>SOLUTION: The infrared dye composition comprises at least a compound (I) whose spectral absorption maximum wavelength in the range of from 400 nm to 1,050 nm is in the range of from 750 nm to 1,050 nm, and a compound (II) whose spectral absorption maximum wavelength in the range of from 400 nm to 1,050 nm is in the range of from 400 nm to 700 nm, wherein when an absorbance of the infrared dye composition at the spectral absorption maximum wavelength in the range of from 750 nm to 1,050 nm is normalized as 1, the maximum absorbance (Dmax) in the range of from 400 nm to 700 nm is 0.5 or lower, and the ratio (Dmax/Dmin) of the maximum absorbance (Dmax) to the minimum absorbance (Dmin) in the range of 400 nm to 700 nm is 10 or lower. <P>COPYRIGHT: (C)2009,JPO&INPIT |
