| 摘要 |
PROBLEM TO BE SOLVED: To suppress leakage of an ink to the outside of a writing utensil as much as possible even under a state wherein the ink exists in an air passage by some unexpected situation by a method wherein for a temporary ink reservoir member, an ink-philic surface is formed, and in a barrel internal wall part which becomes the air passage, an ink-phobic surface is formed. SOLUTION: On the opening side in a barrel cylinder 1, a temporary ink reservoir member 2 is attached, and the bottom side is made an ink tank 3. In a central hole 2a, a nib part comprising a joint part 6a and a ball-point pen tip 6b, and an ink joint core 5 made of a fiber bundle are inserted. The temporary ink reservoir member 2 has a plurality of comb tooth-form parts 2c on the outside, and spaces between respective comb tooth-form parts 2c become a temporary ink reservoir part 2b having a capillary force. On the barrel, cylinder internal wall 1b and the surface of the press-bonding face of a circumferential press-bonding part 7, an ink-phobic treatment is applied, and on the temporary ink reservoir part 2b, an ink-philic treatment is applied. By this method, an ink which has come out to the air passage by an impact or an excessive flow-out, is prevented from reaching an air hole 8. |
