| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a fluorescent ink composition not generating an ooze and excellent in dispersion stability, light resistance and water resistance, to obtain a high concentration fluorescent mark formed from the fluorescent ink composition, and to obtain an infrared light fluorescent mark of being well read even when the infrared light fluorescent mark is disposed on an infrared light- absorbing article to be marked, and suitable for the highly dense formation of bar codes. SOLUTION: This fluorescent ink composition and this fluorescent mark each contains water-dispersible colloidal silica having a resin component on the surface and exhibiting fluorescence in a visible light region. The infrared light fluorescent ink composition and this infrared light fluorescent mark each contains water-dispersible colloidal silica having a resin component on the surface, absorbs infrared light in wavelengths of >=700nm and exhibits infrared light in an infrared light region.</p> |
