| 摘要 |
PROBLEM TO BE SOLVED: To provide a ballpoint pen chip having a simple structure which allows ink to be easily returned and suppresses an inner wall of a chip front end from being worn while obtaining a stable amount of an ink outflow, and also provides favorable writing feeling and favorable hand writing, and a ballpoint pen using the ballpoint pen chip.SOLUTION: In a ballpoint pen chip, a ball seat having a curved surface shape is formed at the bottom wall of a ball holding chamber, a seal surface having a curved surface shape is formed at the inner wall of a chip front end, in a longitudinal section, the intersection of lines connecting the front end edge of the ball seat and the front end edge of the seal surface in a position axially facing the front end edge of the ball seat passes through the nearly center of the ball, a carbonaceous film is formed on the surface of the ball and/or the inner surface of the ball holding chamber, and the carbonaceous film has a carbon atom and an oxygen atom which is combined with the carbon atom. |
