| 摘要 |
PROBLEM TO BE SOLVED: To obtain a photochromic aqueous ink composition for ball-point pen which is excellent in dispersion stability, and at the same time, has photochromic property. SOLUTION: This photochromic aqueous composition is an aqueous ink composition for ball-point pen containing a water-soluble resin, a water-soluble organic solvent and water as essential components, and it contains at least a photochromic coloring material as a coloring agent. Further, another coloring agent is included. The average particle size of the photochromic coloring material is <=40μm. The content of the photochromic coloring material is 1-30 wt.% based on the total amount of the ink composition. The ink composition has a viscosity of 1,000-10,000 mPa.s at 20 deg.C. |
