| 摘要 |
PROBLEM TO BE SOLVED: To provide: an oil-based ballpoint pen refill having a satisfactory drawing line concentration from the beginning to the end while reducing wear of a ball receiving seat; and a ball-point pen including the same.SOLUTION: A writing ball 30 having a diameter of 0.15 mm or larger and 0.45 mm or smaller is accommodated in a ball house 24. The writing ball 30 is pressed rearward on a bottom surface 24a of the ball house 24, thereby forming a ball receiving seat 25 onto which a curved surface of the writing ball 30 is transferred. A distance that the writing ball 30 is movable along an axial direction in the ball house 24 is 0.005 mm or longer and 0.025 mm or shorter. An area of the ball receiving seat 25 is 7% or more with respect to the surface area of the writing ball 30. |
