| abstract |
PROBLEM TO BE SOLVED: To prevent ink viscosity from rising excessively even when water in the ink evaporates, and thus, has excellent dry-up resistance, does not cause problems such as blurring or sagging of handwriting, and stable ink ejection properties. A water-based ink composition for ballpoint pens and a ballpoint pen containing the same are provided. A water-based ink composition for ballpoint pens comprising at least a colorant, water, a shear thinning agent, a thickening inhibitor such as an oligomer of N-vinyl-2-pyrrolidone, and a sulfur-based extreme pressure agent. And a ballpoint pen that houses it. [Selection figure] None |