| 摘要 |
PROBLEM TO BE SOLVED: To provide a water base pigmented ink composition for ballpoint pens which composition is excellent in the long-term stability and lubricating property, gives no wear of the ball seat for a metal tip, keeps an equal ink outflow during the writing, has both a uniform written-line density and a long writable distance, and also has no run of the ink and no ink leakage from the point of the metal tip, and besides has an effect on the control of the corrosion of the metal tip and an extremely good feeling on the writing touch. SOLUTION: The water base pigmented ink composition for ballpoint pens, containing a pigment, a water soluble resin and a water soluble solvent, is characterized by containing a nonionic fluorine-containing surfactant as the main component, a phosphate of a polyoxyethylene alkyl ether, and a fatty acid ester of a polyglycerine or a fatty acid ester of a polyoxyethylene sorbitane, by having the surface tension in the range of 25-30 dyn/cm, and by adjusting the pH value thereof so as be 7.5-9.0. |
