| 摘要 |
PROBLEM TO BE SOLVED: To provide a ballpoint pen which is quite different apparently from a usual writing implement, although it can write with an ink presenting a prescribed color at the writing tip. SOLUTION: A tip part having a penpoint of the ballpoint pen provided at the front end and an ink holding tube provided in the rear is fixed to the front-end opening part of a case tube of which the rear end is closed, and the tip part is so provided that the rear end of the ink holding tube thereof and the inner surface of the rear end part of the case tube are spaced properly from each other. A ring-shaped follower is provided between the inner surface of the case tube and the outer surface of the ink holding tube and the front of the follower communicates with external air, while a liquid for ink is held in the rear of the follower. Moreover, the liquid for ink penetrates into the rear inside the ink holding tube. A coloring agent for coloring the liquid for ink is held in front of the liquid and added thereto in the course of the liquid being guided to the fore end for writing as the writing is conducted. |
