| 摘要 |
An oil-based ink composition for a ball-point pen that enables suppression of a blobbing phenomenon by controlling the internal cohesion force of an ink is provided; An oil-based ink composition for a ball-point pen at least comprising a colorant, a resin, and from 0.01 to 1.5 % by weight of a high polymerization degree polybutyl vinylal with a polymerization degree of 900 (theoretical molecular weight of 60,000) or more and comprising, as a main solvent, a solvent selected from alcohols, polyhydric alcohols, and glycol ethers with a vapor pressure at 25° C. of 0.001 mmHg or higher by 50% or more for the entire solvent. Further, an oil-based ink composition for use in a ball-point pen having a smooth feel in writing, and excellent in the improvement for the fastness and the dispersion stability of the coloring pigment is provided; an oil-based ink composition for use in a ball-point pen containing, as a main solvent, a solvent of the chemical structural formula (1) where R1, R2, and R3 each represents independently H or CH3.
|
