Patent ID: 6331373
Filing Date: 2001-12-18
Classification: G03G

Abstract:
An electrostatic image developer, which comprises:toner particles comprising (a) a binding resin and (b) a coloring agent and having a mean particle diameter of not more than 25 .mu.m; and(c) organic-inorganic composite particles which exist in a portion selected from the surface and the proximity of surface of said toner particles, in a state being one of attached and fixed, and wherein said composite particles comprise an organic polymer framework and a polysiloxane framework, wherein said polysiloxane framework comprises a three-dimensional network which is formed by continuous chemical bondage of siloxane units represented by the following formula: ##STR14##and said polysiloxane framework has in the molecule thereof, an organosilicon moiety which has a silicon atom to which at least one carbon atom in said organic polymer framework is combined directly, wherein said organic polymer framework comprises a main vinyl polymer chain formed of repeating units --C--C--, said organic-inorganic particles having SiO.sub.2 as a component of said polysiloxane framework at a content in the range of 10 to 90% by weight, and said composite particles having a mean particles diameter in the range of 0.01 to 5 .mu.m;the mixing ratio of (b) said coloring agent to (a) said binding resin in said toner particles being 20 to 2 parts by weight of (b) said coloring agent to 80 to 98 parts by weight of (a) said binding resin, wherein the total amount of (a) and (b) is 100 parts; andthe mixing ratio of said organic-inorganic composite particles to said toner particles being 0.01 to 20 by weight of said organic-inorganic composite particles to 100 parts by weight of said toner particles.