| 摘要 |
PROBLEM TO BE SOLVED: To provide a ball point pen which does not generate clogging of ink and exhibits smooth feeling of writing even when a water-based ink containing a glass flake pigment is used. SOLUTION: A seat part 45 of a ball storing room 40 for a ball point pen chip 5 is converged to a central hole 46 and communicates with an ink through- hole 12. A cross-shaped radially extending channel 47 is provided on the seat part 45. Width of the channel 47 is 0.15-0.5 mm and more preferably 0.20-0.35 mm. There exists a gap 48 of 40-80 μm between the ball for writing and the ball storing room 40 at the equatorial part of the ball for writing. The opening part of the ball storing room 40 is caulked to ensure the gap 48 of 40-80 μm on any part of the part which is a site on the exposed side from the equator of the ball for writing and is in the ball storing room 40. |
