Abstract: An image forming apparatus includes a photoreceptor drum, a developing roller, and a control section. The photoreceptor drum is configured to form an electrostatic latent image on a surface thereof in accordance with image data. The developing roller has a surface for bearing a two-component developer at least a partial region of which faces the photoreceptor drum and is configured to be driven so as to feed the developer to the photoreceptor drum. The control section is configured to detect a print coverage for image data to be used during continuous formation of images in accordance with plural image data items and then set a relative velocity of the developing roller to the photoreceptor drum to a higher value when the print coverage is relatively high and set the relative velocity to a lower value when the print coverage is relatively low.

Abstract: A method of manufacturing toner particles capable of decreasing the manufacturing costs by simplifying the manufacturing apparatus and by decreasing the number of the steps, as well as to provide toner particles, a two-component developer, a developing apparatus and an image forming apparatus are provided. A high-pressure homogenizer is constituted by a tank, a feed pump, a high-pressure pump, a heat exchanger, a nozzle, a first depressurizing module, a cooling unit, a second depressurizing module and a take-out port arranged in this order. A flow path constituted in the first depressurizing module has a straight portion tilted with respect to a direction in which the aqueous slurry passes and a portion for relaxing the flow of the aqueous slurry.

Abstract: A toner includes a binder resin containing a polyester resin A obtained by subjecting aromatic dicarboxylic acid, rosin, and trivalent or higher-valent alcohol as starting materials to polycondensation, a content of the rosin in a sum of the starting materials being 60% by weight or more, and a polyester resin B obtained by subjecting aromatic dicarboxylic acid and polyalcohol as starting materials to polycondensation; a dispersing aid for dispersing the polyester resin A into the polyester resin B; and a colorant.

Abstract: A toner includes a binder resin and a colorant. The binder resin contains a polyester resin A obtained by subjecting aromatic dicarboxylic acid, rosin, and trivalent or higher-valent alcohol as starting materials to polycondensation, a content of the rosin in a sum of the starting materials being 60% by weight or more, and a polyester resin B obtained by subjecting aromatic dicarboxylic acid and polyhydric alcohol as starting materials to polycondensation, the polyester resin B having a viscosity of 103 Pa·s or more and 105 Pa·s or less at a softening temperature of the polyester resin A, the polyester resin B being contained in an amount of 50 parts by weight or more and 200 parts by weight or less relative to 100 parts by weight of the polyester resin A.

Abstract: A toner includes a binder resin, a colorant, and, a benzilic acid compound. The binder resin contains a polyester resin A obtained by subjecting aromatic dicarboxylic acid, rosin and trivalent or higher-valent alcohol as starting materials to polycondensation, a content of the rosin in a sum of the starting materials being 60% by weight or more, and a polyester resin B obtained by subjecting aromatic dicarboxylic acid and polyhydric alcohol as starting materials to polycondensation.

Abstract: A functional particle is manufactured by a method including an aggregating step, a depressurizing step, and a cooling step. In the aggregating step, the functional particle is obtained by flowing a mixed slurry containing a core particle and a shell particle through a coiled pipeline while heating the mixed slurry to a glass transition temperature or higher of the core particle, to deposit the shell particles on the surface of the core particle. In the depressurizing step, the grain size of the functional particle is controlled and the coarse particle is pulverized to make the grain size of the functional particles uniform. In the cooling step, re-aggregation of the functional particles with unified grain size is prevented.

Abstract: A method of manufacturing a toner is provided which is excellent in low temperature fixation property, whose fixable temperature width is large, as well as excellent in durability while giving consideration to the global environment conservation. The method of manufacturing a toner includes a step of producing a polyester resin by a reaction of dicarboxylic acid and diol, and a step of producing a toner base particle having the polyester resin and a colorant. The dicarboxylic acid is a biomass monomer having carboxyl groups introduced into ends of one, or two or more monocarboxylic acids selected from pimaric acid, isopimaric acid, and sandaracopimaric acid.

Abstract: A developing device capable of improving the image density and the dot reproducibility, and an image forming apparatus including the same are provided. A developing device applies an alternating voltage superimposed on a direct current voltage to a developing roller to thereby develop an electrostatic latent image formed on a photoreceptor with toner. A bias voltage waveform superimposed at this time has an original period (first period) in which each of a development-side electrical potential and an opposite development-side electrical potential is applied one time and a period (second period) in which a Vpp is gradually increased from the initial value to the maximum value.

Abstract: Toner having good dispersibility of a pigment and a release agent therein and having excellent low temperature fixability is provided. The toner includes a binder resin, a pigment and a release agent, and the binder resin includes a graft polymer in which abietic acids and a fatty acid are grafted to a polyfunctional epoxy resin. Image is formed using such a toner.

Abstract: A method of manufacturing toner particles capable of decreasing the manufacturing costs by simplifying the manufacturing apparatus and by decreasing the number of the steps, as well as to provide toner particles, a two-component developer, a developing apparatus and an image forming apparatus are provided. A high-pressure homogenizer is constituted by a tank, a feed pump, a high-pressure pump, a heat exchanger, a nozzle, a first depressurizing module, a cooling unit, a second depressurizing module and a take-out port arranged in this order. A flow path constituted in the first depressurizing module has a straight portion tilted with respect to a direction in which the aqueous slurry passes and a portion for relaxing the flow of the aqueous slurry.

Abstract: A method of manufacturing aggregate particles capable of obtaining aggregate particles having high mechanical strength, small particle size, with narrow particle size distribution width by preventing interfusion of bubbles in the aggregate particles during stirring is provided. Aggregate particles are manufactured by stirring a resin particle slurry including resin particles dispersed in an aqueous medium and contained in a stirring vessel by a stirring section having a impeller and two or more screen members disposed so as to surround the impeller in the stirring vessel and each formed with a plurality of slits and aggregating the resin particles.

Abstract: The development device of this invention includes a developer bearing member, a magnet, and a developer regulation member. The magnet is fixedly disposed within the interior of the developer bearing member. The developer regulation member includes at least a magnetic member. And the thickness of this magnetic member along the rotational direction of the developer bearing member is between 0.2 mm and 0.4 mm inclusive. Moreover, if the distance over the developer bearing member, from the position thereupon which the center of the magnetic member along the rotational direction opposes, to the position thereupon at which the magnetism of that magnetic pole which is disposed closest to that position is a maximum, is termed L (mm), and the diameter of the developer bearing member is termed D (mm), then the magnetic member is disposed within the range in which the relationship 0?L/D?0.044 holds.

Abstract: A method of manufacturing toner particles capable of decreasing the manufacturing costs by simplifying the manufacturing apparatus and by decreasing the number of the steps, as well as to provide toner particles, a two-component developer, a developing apparatus and an image forming apparatus are provided. A high-pressure homogenizer is constituted by a tank, a feed pump, a high-pressure pump, a heat exchanger, a nozzle, a first depressurizing module, a cooling unit, a second depressurizing module and a take-out port arranged in this order. A flow path constituted in the first depressurizing module has a straight portion tilted with respect to a direction in which the aqueous slurry passes and a portion for relaxing the flow of the aqueous slurry.

Abstract: The aggregated particles are manufactured through a method of manufacturing aggregated particles, which includes an aggregating step, a depressurizing step, and a cooling step. In the aggregating step, a slurry is prepared which contains aggregated particles obtained by flowing an aqueous slurry of resin fine particles having a volume average particle diameter in the range of 0.4 ?m to 3 ?m through a coiled piping in a heated and pressurized state and thereby aggregating the resin fine particles. In the depressurizing step, the slurry containing the aggregated particles is depressurized, and a particle size control is conducted by disintegrating coarse particles so as to homogenize particle diameters of the aggregated particles. In the cooling step, the slurry containing the aggregated particles of which particle diameters have been homogenized is cooled.

Abstract: A capsule toner in which fine solid particles constituting a shell layer are less likely to become detached from the surfaces of toner particles in spite of a long-term use within an image forming apparatus and which is capable of prevention of occurrence of filming on a photoreceptor drum, and a method of manufacturing the capsule toner are provided. The capsule toner includes core particle and shell layers for covering the surface of the core particle. The shell layer is formed of a plurality of fine polyester resin particles. The polyester resins contained in the fine polyester resin particles, respectively, are cross-linked to each other by a cross-linking agent.

Abstract: A developing device and an image forming apparatus capable of restraining density irregularity and restraining a decline in image quality caused by adherence of carrier to a photoreceptor, are provided. An angle ? is in a range of no less than 45 degrees nor more than 57 degrees, which is formed between a plane comprising a central line of magnetic pole formed by a regulating pole in a magnet roller and a rotating central axis of a developing sleeve and a plane comprising a central line of magnetic pole formed by a pumping pole and a rotating central axis of the developing sleeve. Further, an absolute value of the maximum value of strength of the magnetic pole formed by a main pole is in a range of no less than 120 mT nor more than 140 mT.

Abstract: There is provided a method of manufacturing coalesced resin particles for obtaining coalesced resin particles by coalescing aggregated resin particles in a grain boundary-free state in a short period of time while keeping a grain size distribution within a narrow range. In a coalescence process, a slurry of aggregated resin particles is flowed through an inside of a pipe under predetermined heating and pressurizing conditions. In a before-cooling decompression process, a slurry of coalesced resin particles flowing through the inside of the pipe in a heat and pressure-applied state is subjected to pressure reduction before it is cooled down to a predetermined temperature in a cooling process. Then, in a decompression process, a coalesced resin particle slurry that has been cooled in the cooling process while being flowed through the inside of the pipe is decompressed to an atmospheric pressure.

Abstract: A developing device capable of improving the image density and the dot reproducibility, and an image forming apparatus including the same are provided. A developing device applies an alternating voltage superimposed on a direct current voltage to a developing roller to thereby develop an electrostatic latent image formed on a photoreceptor with toner. A bias voltage waveform superimposed at this time has an original period (first period) in which each of a development-side electrical potential and an opposite development-side electrical potential is applied one time and a period (second period) in which a Vpp is gradually increased from the initial value to the maximum value.

Abstract: An image forming apparatus includes a photoreceptor drum, a developing roller, and a control section. The photoreceptor drum is configured to form an electrostatic latent image on a surface thereof in accordance with image data. The developing roller has a surface for bearing a two-component developer at least a partial region of which faces the photoreceptor drum and is configured to be driven so as to feed the developer to the photoreceptor drum. The control section is configured to detect a print coverage for image data to be used during continuous formation of images in accordance with plural image data items and then set a relative velocity of the developing roller to the photoreceptor drum to a higher value when the print coverage is relatively high and set the relative velocity to a lower value when the print coverage is relatively low.

Abstract: A method of manufacturing toner particles capable of decreasing the manufacturing costs by simplifying the manufacturing apparatus and by decreasing the number of the steps, as well as to provide toner particles, a two-component developer, a developing apparatus and an image forming apparatus are provided. A high-pressure homogenizer is constituted by a tank, a feed pump, a high-pressure pump, a heat exchanger, a nozzle, a first depressurizing module, a cooling unit, a second depressurizing module and a take-out port arranged in this order. A flow path constituted in the first depressurizing module has a straight portion tilted with respect to a direction in which the aqueous slurry passes and a portion for relaxing the flow of the aqueous slurry.