| abstract |
(57) [Summary] [Construction] Consists of a color pigment and a liquid medium, and further contains alumina, silicon carbide, chromium oxide, boron carbide, zircon, senalite, jadeite, calcium fluoride, tungsten carbide, silica, and diamond. Aqueous pigment ink for ballpoint pens containing fine particles having a new Mohs' hardness of 4 or more, such as garnet, aluminum nitride, and silicon nitride. [Effect] The wear of the ball seat due to the rotation of the ball during writing can be reduced. Therefore, writing is possible without fading until the ink is consumed. |