| 摘要 |
PROBLEM TO BE SOLVED: To provide an ink backflow prevention body composition having high practicability excellent in visibility and aging stability, which satisfies backflow prevention performance, ink follow-up performance and shock resistance and, further, can suppress addition of ink to an ink storage cylinder inner wall surface.SOLUTION: An ink backflow prevention body composition made of hardly-volatile liquid and a gelation agent which is arranged on a rear end surface of ink directly stored within an ink storage cylinder of a writing instrument and advances in accordance with consumption of the ink is made by containing Nε-lauroyl-L-lysine less than 3 wt.% in the whole amount of the ink backflow prevention body composition.SELECTED DRAWING: None |
