| 摘要 |
PROBLEM TO BE SOLVED: To provide an ink storage tube without causing leakage due to a capillary phenomenon generated in a gap between unevenness and a ballpoint pen tip even when a boundary between a welded part and a non-welded part of the ink storage tube is not smoothed and the unevenness is continuously present in a longitudinal direction.SOLUTION: In a ball-point pen refill 1 obtained by press fitting a metallic ballpoint pen tip 2 rear end rotatably embracing a ball 2b into a tip end of a metallic ink storage tube 3, the ink storage tube has elongation of 20-60% and yield strength of 20-50 kgf/mm. |
