| 摘要 |
<p>An aqueous ink composition is provided which includes an aqueous mixture containing at least a coloring agent, a pigment dispersant, a water-soluble organic solvent and water, and an organic white pigment of an alkylene-bis-melamine derivative represented by the general formula (1): <CHEM> wherein R represents a hydrogen atom, a lower alkyl group having 1 to 4 carbon atoms or an alicyclic group; R1, R2, R3 and R4 are the same or different, each representing a hydrogen atom or a lower alkyl group having 1 to 4 carbon atoms; R1 and R2, or R3 and R4 may form a heterocyclic group together with a nitrogen atom; and X represents a lower alkylene group having 2 to 3 carbon atoms. The aqueous ink composition is particularly useful for writing instruments of direct ink supply type and of wick type.</p> |
