| 摘要 |
PROBLEM TO BE SOLVED: To provide a water-based ink composition for writing implement in which good handwritings are obtained, while preventing bubbles to generate in ink, and to provide a writing implement with built-in the same. SOLUTION: The water-based ink composition composed of a coloring agent, water, water soluble organic solvent and thiourea dioxide shown by the formula (1) and/or formamidinesulphinic acid shown by the formula (2), and the writing implement with built-in the same are provided. |
