The greasy ballpoint pen ballpoint pen of printing ink composition

摘要

PROBLEM TO BE SOLVED: To provide an oily ball point pen ink generating no fore-end leak and capable of providing smooth and light writing feeling even with long time storage for improving defects of conventional oily ball point pen inks.SOLUTION: There is provided an ink composition for oily ball point pen containing at least a coloring agent, a polar organic solvent, silica and a reinforcer of the silica and having carbon percentage content of the silica of 1.5 mass% or less including 0, where the reinforcer has a group interacting with a surface of the silica and a group having compatibility with the polar organic solvent.SELECTED DRAWING: None