| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject composition free from troubles, affording smooth writing feeling, and satisfying cap-off property writing performance and storage performance by including a specific surfactant and others. SOLUTION: This ink composition essentially comprises water, (A) a pigment, (B) a surfactant, (C) a pH adjustor, (D) a shear viscosity reducing agent, and (E) a moisturizer; wherein the component B is a compound of the formula: RO(CH2CH2O)nSO3M [R is a 8-20C (un)saturated hydrocarbon; n is 3-30; M is an alkali metal, ammonium, alkylamine, or the like], the component D is an alkali-swellable acrylic emulsion, and the component E is diethylene glycol singly or a mixture of ethylene glycol and diethylene glycol; and it is preferable that the component C is ammonia, an amine or inorganic salt, and this ink composition has a pH of >=8. |
