ELECTROSTATIC LATENT IMAGE DEVELOPING TONER AND METHOD AND DEVICE FOR FORMATION OF IMAGE USING THE SAME

摘要

PROBLEM TO BE SOLVED: To improve the stability for a long time when a toner produced by melting and depositing resin particles in an aq. medium is used, by controlling the particle size of resin particles which constitute the toner and the particle size of a large-size external additive to satisfy specified relation. SOLUTION: In an electrostatic latent image developing toner consisting of an external additive and color particles produced by melting and depositing at least resin particles in an aq. medium, the number average primary particle size (A nm) of the external additive and the weight average particle size (B nm) of the resin particles satisfy the relation of 0.1<=B/A<=1.0 and B=50 to 2,000 nm. As for the fine particles used as the external additive, various kinds of inorg. fine particles, org. fine particles or the like can be used. As for the inorg. fine particles, for example, oxides such as silica, alumina, titania and zirconia, nitrides and borides can be used, and as for the org. fine particles, for example, a styrene resin, styrene/acrylic resin, polyester resin and urethane resin can be used. Thus, decrease in the max. density or production of fog can be prevented even for long-term use.