| 摘要 |
PROBLEM TO BE SOLVED: To obtain a vermilion ink composition useful for ink-jet recording, etc., scarcely causing the clogging of nozzles, maintaining a clear color tone and excellent in long-term storage stability, by dispersing mixed pigments and a dispersant into water under specified conditions. SOLUTION: This vermilion ink composition comprises at least mixed pigments, which comprise two or more kinds of pigments preferably comprising a magenta pigment and a yellow pigment, in an amount of, preferably, 0.1-20 wt.% (based on the total weight of the composition), a dispersant, such as an anionic surfactant, in an amount of, preferably, 0.1-20 wt.%, and water. Therein, the pigments are dispersed by the use of ceramic beads having an average diameter in a range of 0.01-1.0 mm. The obtained vermilion ink composition has a color tone satisfying the following inequities: 25<=L*<=50, 47<=a*<=60 and 37<=b*<=60, when measured at a 10 deg. viewing field under the standard illuminant D65 and expressed in the L*-a*-b* chromaticity system. The composition further has a surface tension in a range of 20-70 dyne/cm and a viscosity of <=10 cp at 25 deg.C. |
