Abstract: An object of the present invention is to provide a liquid developing electrographic device roller suppressed in volumetric variation caused by a carrier. As a means for solving the problems, the present invention provides a liquid developing electrophotographic device roller including a shaft and an elastic material layer provided around the outer peripheral side of the shaft, wherein the elastic material layer is formed by using a polyurethane obtained by reacting a polyester polyol with a difunctional isocyanate.

Abstract: An object of the present invention is to provide a liquid developing electrographic device roller suppressed in volumetric variation caused by a carrier. As a means for solving the problems, the present invention provides a liquid developing electrophotographic device roller including a shaft and an elastic material layer provided around the outer peripheral side of the shaft, wherein the elastic material layer is formed by using a polyurethane obtained by reacting a polyester polyol with a difunctional isocyanate.

Abstract: What is disclosed a decolorizable toner of which main components are a visible ray-near infrared ray-absorbing dye, a decolorizing agent and a resin binder, characterized in that a resin binder A containing the visible ray-near infrared ray-absorbing dye is dispersed in a resin binder B and that the decolorizing agent is blended with at least one of the resin binder A and the resin binder B, and a process for preparing the same. The visible ray-near infrared ray-decolorizable toner of the present invention can be speedily decolorized by irradiating with visible rays to near infrared rays. Also, according to the process of the present invention, it is easy to adjust its electrically charged amount by a material having electrification property, and there is obtained a visible ray-near infrared ray-decolorizable toner which is hardly faded during the kneading in the production of the toner.

Abstract: A decolorizable toner including a resin binder, a near infrared ray-absorbing dye, a decolorizing agent and a light fastness stabilizer, and a process for preparing the decolorizable toner, which includes the steps of mixing the near infrared ray-absorbing dye and the light fastness stabilizer with the resin binder, and then mixing the decolorizing agent therewith. The decolorizable toner has excellent light stability during its production or storage and excellent decolorizing property.

Abstract: There is disclosed a method of producing a toner particles for use in electrophotography which comprises: suspending a radical polymerizable monomer which contains a colorant and a charge controlling agent therein in an aqueous phase; suspension polymerizing the monomer to provide spherical polymer particles of 1-30 .mu.m in diameter; treating the suspension containing the polymer particles with a continuous, wet type, agitation mill, to deform the polymer particles.A further method of producing toner particles is disclosed which comprises: producing spherical polymer particles by suspension polymerization of a monomer; making finely divided triboelectric or electroconductive particles or both onto the surface of the polymer particles; and then mechanically pressing the polymer particles to deform the polymer particles as well as to fix the particles on the surface of the polymer particles.