abstract |
The surface of a base pigment is modified so as to have a specific functional group such as sulfonic acid or its derivative, in order to increase rheological and colouristic properties and flocculation stability of dioxazine pigments (e.g., Pigment Violet 23). By modifying a pigment surface and further kneading it, dispersibility and the efficiency (brightness) of a color filter are improved without any other adverse effects. |