| abstract |
(57) [Summary] [PROBLEMS] To prevent bubbles from being generated in ink, Provided are a water-based ink composition for a writing instrument from which a good handwriting can be obtained, and a writing instrument incorporating the same. SOLUTION: An aqueous ink composition for a writing implement comprising a colorant, water, a water-soluble organic solvent, a shear thinning agent, and a synthetic polyphenol, and a writing implement incorporating the same. |