| 摘要 |
An object is to make an ink composition for a ballpoint pen, ensuring that the width of writing line is thin, even slight unevenness or feathering does not occur at the boundary between the writing line and a paper sheet, ink-depleted writing line that is writing line in a state of ink being lacked near the central part of writing line is prevented, and the writing line is clear. The ink viscosity is set to 200,000 mPa·s or more at a shear rate of 0.019 s -1 and 5,000 mPa·s or less at a shear rate of 10,000 s -1 and the storage modulus at an angular frequency of 0.019 rad/sec is set to 10 Pa or more. |
