| 摘要 |
PURPOSE:To reduce the amt. of carbon black and to secure the picture density while maintaining the insulating property of a toner as a whole by incorporating carbon black and inorg. blue pigment. CONSTITUTION:As for the inorg. blue pigment, inorg. blue pigment such as dark blue or ultramarine having low charge supplying property is used. The preferable amt. of the pigment is 0.1 - 5 wt.%. Any carbon black generally used can be used and is added by 2 - 8 wt.%, preferably. By this method, the amt. of carbon black can be decreased in the toner, while increase in charge is prevented by adding the inorg. blue pigment having low charge supplying property. Thus, the obtd. picture image has proper charge holding property, excellent light shielding property, high picture density and excellent printing resistance. |
