| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject composition excellent in color tone as a black ink, improved in light resistance and water resistance, and useful for ink jet printing, by including a specific colorant. SOLUTION: This composition is obtained by including (A) 1-5 wt.% of a water-dispersible or water-soluble colorant comprising (i) a compound of formula I [A and B are each COOR or SO3 R (R is H, a quaternary ammonium, etc.); D is H or CH2 COOH; T is H, quaternary ammonium, etc.], (e.g. a compound of formula II) and (ii) a compound of formula III (Z is an alkanolamino or OH; M is an alkali metal, quaternary ammonium, etc.; (l) and (m) are each 0-3) (e.g. a compound of formula IV) in a weight ratio (i)/(ii) of (5:1) to (25:1), (B) a wetting agent such as diethylene glycol, and (C) water, so as to adjust to pref. pH7-11. This composition is useful in water-based writing utensils, recorders, pen plotters, etc. |
