| 摘要 |
PROBLEM TO BE SOLVED: To prevent a backflow preventing material from causing a phenomenon of reversal in relation with ink and, moreover, to enable execution of excellent writing and also clear writing on dark color paper such as black paper. SOLUTION: This ball-point pen is so constructed that ink and an ink backflow preventing material are filled in an ink storage tube to one end of which a pen point of the ball-point pen is fitted. In this case, the ink contains titanium oxide of 25wt.% or above to the whole quantity of the ink, and a difference in specific gravity between this ink and a base material constituted of chlorinated paraffin, fluoroalkoxycyclotriphosphazene, etc., and used for the backflow preventing material (the specific gravity of the ink-the specific gravity of the base material) is made 0.2 or below. |
