| 摘要 |
PROBLEM TO BE SOLVED: To provide an oil-based ink composition for ballpoint pen, which can provide a light writing touch without ink leakage, and never causes blur of writing.SOLUTION: An oil-based ink composition for ballpoint pen includes at least: ethyl cellulose; an organic solvent having a solubility parameter (SP value) of 8.0-9.5 and containing oxypropylene group in the molecule; and an organic solvent having a solubility parameter (SP value) of 8.0-9.5 and containing a hydroxyl group but not containing an oxypropylene group in the molecule. |
