| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide offset ink composed of four process colors of yellow, red, indigo blue and black that can extremely reproduce the RGB color reproduction region. <P>SOLUTION: The ink composition for offset printing uses any two or three of (a) yellow ink, (b) red ink and (c) indigo blue ink, and black ink, where the yellow ink and the red ink are a pigment below, respectively. The yellow ink (a) contains 5-15% of a compound of a yellow hue having a reflection spectrum that has a reflectance of 1-20% within the wavelength range of 400-480 nm and a reflectance of 90-100% within the wavelength range of 530-700 nm and the red ink (b) contains 15-20% of a compound of a red hue having a reflection spectrum that has the maximum reflectance of 50-100% within the wavelength range of 400-500 nm, a reflectance of 1-20% within the wavelength range of 500-560 nm and a reflectance of 90-100% within the wavelength range of 630-700 nm, each ink having the maximum reflectance of 100% within the range of 400-700 nm. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
