| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a superfine water-based gel ink ballpoint pen which is free from phenomenons of an oscillation scratch, dry-up, blurring and direct running and has a stable and excellent feel in writing. <P>SOLUTION: The water-based gel ink ballpoint pen holds rotatably a ball having an outside diameter of 0.25 mm or less inside a ballpoint pen tip holder and holds water-based gel ink in an ink holding part. The viscosity of the ink is 200-600 mPa s at the temperature of 25°C and under the condition of a rotation speed of 1 rpm by a cone plate type rotation viscosimeter (1°34'R24 cone), and the n value of a non-Newtonian viscosity index of the ink is 0.40-0.80. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
