| 摘要 |
PURPOSE:To increase the lightness of a color toner and to make an image clear by forming a thin film consisting of fine particles having a high refractive index on the outside of a coloring material layer coating a core substance. CONSTITUTION:A core substance 1 based on magnetic particles is coated with a coloring material layer 2 contg. a colorant and the layer 2 is further coated with a thin film 3 consisting of fine particles having a high refractive index to obtain a magnetic color toner. The fine particles are preferably made of an inorg. pigment having >=2.0 refractive index and the particle size of the fine particles is preferably regulated to <=0.1 mum. When titanium dioxide is deposited as the fine particles, the core substance 1 coated with the layer 2 is suspended in a dil. highly acidic soln. of titanium (IV) sulfate at room temp., the resulting suspension is boiled by rapid heating and hydrolysis is completed. |
