| 摘要 |
PROBLEM TO BE SOLVED: To form a color image having a good hue and a good black image by selecting and adjusting a diluted soln. of a soln. prepared by mixing cyan, magenta and yellow inks of which the hue angles are specific values in an equal ratio so as to set the brightness and chroma thereof to specific values. SOLUTION: A soln. permeation color by 200-time dilution is measured under a measuring condition of a D65 light source 2 deg. visual field and a permeation light pass length of 10mm and a hue angle H deg. is represented by an L*a*b* color system. A soln. of a soln. prepared by mixing cyan ink with a hue angle H deg. of 230-260 deg., magenta ink with a hue angle H deg. of 330-360 deg. (0 deg.) in a concn. equal to that of the cyan ink and yellow ink with a hue angle H deg. of 85 deg.-115 deg. in a concn. equal to that of the cyan ink in an equal ratio. The brightness L* of the 66-time diluted soln. of this soln. is adjusted to 4 or less and the chroma C* thereof is adjusted to 10 or less. This recording ink can record a well-balanced good hue color image and the black image formed by this method has a natural black color and is excellent in gradation properties and recording of high optical density can be performed. |
