ELECTROSTATIC LATENT IMAGE DEVELOPING TONER AND IMAGE FORMING METHOD AS WELL AS IMAGE FORMING DEVICE

摘要

PROBLEM TO BE SOLVED: To obtain toners which do not give rise to toner spilling and splashing while using a system for simultaneous pressurized contact heat fixing of superposed toner images by forming the toners by fusing at least resin particles in an aqueous medium. SOLUTION: The toners are prepared by fusing the resin particles in the aqueous medium. The resin particles preferably have a weight average molecular weight of 50 to 2000 nm. The resin particles are produced by a granulation polymerization method, such as emulsification polymerization. At least one kind of a radical polymerizable monomer having an acidic group or a radical polymerizable monomer having a basic group is preferably incorporated as a polymerizable monomer into the toners. The grain size of the toners is preferably 3 to 9μm in volume average grain size. The shape of the toners is preferably such that the toner particles having a shape coefficient ((maximum diameter/2)2×π/projection area) within a range of 1.3 to 2.2 and having the shape coefficient within a range of 1.5 to 2.0 are preferably >=80 number%.