| 摘要 |
PROBLEM TO BE SOLVED: To provide an ink which spreads to an appropriate degree in the direction of the surface of a recording medium, with controlled penetration in the direction of thickness thereof, and, as a result, can give dots having diameters with a suitable spread, containing therein an image of high and uniform density, and excellent in external shape almost free from feathering observed. SOLUTION: An ink is prepared by incorporating coloring materials comprising a self-dispersible first pigment having at least one anionic group bonded directly or through other atomic group to the surface thereof, and a second pigment dispersible by a polymeric dispersant in an aqueous medium, and a polymeric dispersant into an aqueous medium, wherein the polymeric dispersant used comprises one containing benzyl methacrylate monomer units or wherein the second pigment used comprises a carbon black having a BET specific surface of not more than 300 m2/g and a DBP oil absorption of not more than 50 ml/100 g. |
