| 摘要 |
PROBLEM TO BE SOLVED: To provide a positively charging toner for electrostatic charge image development, the toner exhibiting good rising property of charging even in a low temperature and low humidity environment, little initial fog, and excellent initial printing performance, for imparting stable chargeability and fluidity with lapse of time to toner particles, keeping thin line reproducibility even after continuous printing in a great number of sheets, hardly causing degradation of image quality such as fog but having excellent durable printing performance even in a high temperature and high humidity environment. SOLUTION: The positively charging toner for electrostatic charge image development contains color resin particles comprising a binder resin, a colorant and a charge control agent, and an external additive, wherein the toner contains, as the external additive, an external additive A and an external additive B. The external additive includes fatty acid alkali metal salt particles or fatty acid alkaline earth metal salt particles having a number average primary particle diameter of 0.1 to 1 μm, with the content of the fatty acid alkali metal salt particles or the fatty acid alkaline metal salt particles being 0.01 to 0.5 part by weight with respect to 100 parts by weight of the color resin particles. The external additive B includes spherical silica fine particles having a number average primary particle diameter of 40 to 200 nm and a sphericity of 1 to 1.3. The content of the spheric silica fine particles is 0.2 to 2 parts by weight with respect to 100 parts by weight of the color resin particles. COPYRIGHT: (C)2010,JPO&INPIT
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