Abstract: Reduction in the power transmission efficiency due to imprecise positioning between a primary power transmission coil and a secondary power reception coil is avoided. For transmitting electric power in a wireless manner to an electronic device including a secondary power reception coil and configured to receive electric power via the secondary power reception coil, a power transmission device includes a primary power transmission coil and a power transmission circuit unit for supplying electric power to the primary power transmission coil, and a transmission circuit unit is formed by the primary power transmission coil and the secondary power reception coil. A first impedance of an input end of the transmission circuit unit is matched with a second impedance of an output end of the transmission circuit unit by using a coupling coefficient between the primary power transmission coil and the secondary power reception coil.

Abstract: Provided is a contactless electric power feeding system that allows a plurality of devices to be recharged at the same time. A feeding device includes a primary feeding coil and each receiving device includes a secondary receiving coil. Each coil forms a resonance circuit jointly with a capacitor, and the two resonance circuits are electro-magnetically coupled with each other to from a transmission circuit unit. A first impedance of an input end of the transmission circuit unit is matched with a second impedance of an output end of the transmission circuit unit by using a coupling efficient between the primary feeding coil and the secondary receiving coil, and the output impedance of a power supply unit for supplying electric power to the primary feeding coil is smaller than the first impedance.

Abstract: Reduction in the power transmission efficiency due to imprecise positioning between a primary power transmission coil and a secondary power reception coil is avoided. For transmitting electric power in a wireless manner to an electronic device including a secondary power reception coil and configured to receive electric power via the secondary power reception coil, a power transmission device includes a primary power transmission coil and a power transmission circuit unit for supplying electric power to the primary power transmission coil, and a transmission circuit unit is formed by the primary power transmission coil and the secondary power reception coil. A first impedance of an input end of the transmission circuit unit is matched with a second impedance of an output end of the transmission circuit unit by using a coupling coefficient between the primary power transmission coil and the secondary power reception coil.

Abstract: A toner or two-component developer is obtained by mixing, aggregating, and heating resin particles, colorant particles, and wax particles in an aqueous medium. A gel permeation chromatography (GPC) measurement of the resin particles shows that a weight-average molecular weight is 10000 to 60000, and the ratio of the weight-average molecular weight to a number-average molecular weight is 1.5 to 6. The wax particles include at least a first wax and a second wax. An endothermic peak temperature (melting point Tmw1 (° C.)) of the first wax based on a DSC method is 50° C. to 90° C. An endothermic peak temperature (melting point Tmw2 (° C.)) of the second wax based on the DSC method is at least 5° C. to 50° C. higher than Tmw1. Thus, the toner can have a smaller particle size and a sharp particle size distribution without requiring a classification process, can achieve a longer life, and can suppress transfer voids or scattering during transfer.

Abstract: A toner or two-component developer is obtained by mixing, aggregating, and heating resin particles, colorant particles, and wax particles in an aqueous medium. A gel permeation chromatography (GPC) measurement of the resin particles shows that a weight-average molecular weight is 10000 to 60000, and the ratio of the weight-average molecular weight to a number-average molecular weight is 1.5 to 6. The wax particles include at least a first wax and a second wax. An endothermic peak temperature (melting point Tmw1 (° C.)) of the first wax based on a DSC method is 50° C. to 90° C. An endothermic peak temperature (melting point Tmw2 (° C.)) of the second wax based on the DSC method is at least 5° C. to 50° C. higher than Tmw1. Thus, the toner can have a smaller particle size and a sharp particle size distribution without requiring a classification process, can achieve a longer life, and can suppress transfer voids or scattering during transfer.

Abstract: A toner includes aggregated particles produced by preparing in an aqueous medium a mixed dispersion including at least a first resin particle dispersion in which first resin particles are dispersed, a colorant particle dispersion in which colorant particles are dispersed, and a wax particle dispersion in which wax particles are dispersed, heating the mixed dispersion so that at least part of the wax particles is melted, and aggregating the first resin particles, the colorant particles, and the wax particles at least part of which is melted by the addition of an aqueous solution containing an aggregating agent. Thus, the toner can have a smaller particle size and a sharp particle size distribution without requiring a classification process. Moreover, the toner can achieve a longer life and suppress transfer voids or scattering during transfer.

Abstract: First toner of the present invention includes colored particles and an external additive. The colored particles are produced by heating and aggregating a mixture that includes a resin particle dispersion in which first resin particles are dispersed and a pigment particle dispersion in which pigment particles are dispersed, so that at least part of the first resin particles is melted. The colored particles have a finely roughened surface. Second toner of the present invention includes aggregated particles including at least first resin particles and pigment particles, and colored particles having a finely roughed surface formed by fusing at least part of wax and at least part of second resin particles on the surface of the aggregated particles.

Abstract: First toner of the present invention includes colored particles and an external additive. The colored particles are produced by heating and aggregating a mixture that includes a resin particle dispersion in which first resin particles are dispersed and a pigment particle dispersion in which pigment particles are dispersed, so that at least part of the first resin particles is melted. The colored particles have a finely roughened surface. Second toner of the present invention includes aggregated particles including at least first resin particles and pigment particles, and colored particles having a finely roughed surface formed by fusing at least part of wax and at least part of second resin particles on the surface of the aggregated particles.

Abstract: A toner or two-component developer is provided. The toner includes toner base particles obtained by mixing in an aqueous medium a first resin particle dispersion, a colorant particle dispersion, and a wax particle dispersion, aggregating the mixed dispersion to form core particles at least part of which is melted, adding a second resin particle dispersion to a core particle dispersion in which the core particles are dispersed, and fusing the second resin particles with the core particles by heating. A GPC measurement of the second resin particles shows that the number-average molecular weight (Mn2) is 9000 to 30000, the weight-average molecular weight (Mw2) is 50000 to 500000, and the ratio (Mw2/Mn2) of the weight-average molecular weight (Mw2) to the number-average molecular weight (Mn2) is 2 to 10. The wax particles include at least a first wax and a second wax. An endothermic peak temperature (melting point Tmw1) of the first wax based on a DSC method is 50° C. to 90° C.

Abstract: A toner or two-component developer is provided. The toner includes toner base particles obtained by mixing in an aqueous medium a first resin particle dispersion, a colorant particle dispersion, and a wax particle dispersion, aggregating the mixed dispersion to form core particles at least part of which is melted, adding a second resin particle dispersion to a core particle dispersion in which the core particles are dispersed, and fusing the second resin particles with the core particles by heating. A GPC measurement of the second resin particles shows that the number-average molecular weight (Mn2) is 9000 to 30000, the weight-average molecular weight (Mw2) is 50000 to 500000, and the ratio (Mw2/Mn2) of the weight-average molecular weight (Mw2) to the number-average molecular weight (Mn2) is 2 to 10. The wax particles include at least a first wax and a second wax. An endothermic peak temperature (melting point Tmw1) of the first wax based on a DSC method is 50° C. to 90° C.

Abstract: A toner of the present invention is a toner comprising an additive and a toner matrix that contains a binder resin, a colorant, and a wax, in which the additive contains an inorganic micropowder to whose surface polysiloxane and at least one selected from fatty acids and derivatives thereof are adhered. Thus, the present invention provides the toner, a two-component developer, and an image forming method with which oil-less fixing is possible without the use of an oil on a fixing roller. Furthermore, the present invention provides the two-component developer that causes less carrier deterioration by toner-spent even when used in combination with a toner containing wax or another such release agent and thus the developer has good durability. In addition, the present invention provides the toner, the two-component developer, and the image forming method with which partial transfer defects are reduced and high transfer efficiency can be obtained.

Abstract: The present invention provides a toner comprising core particles that contain at least first resin particles, colorant particles, and wax particles, in an aqueous medium, wherein the core particles contain nucleus particles in which the first resin particles and the colorant particles are aggregated and particles in which the first resin particles and the wax particles are aggregated. Accordingly, the treatment time for forming the core particles can be shortened, generation of colorant particles or wax particles that are not aggregated but suspended in a liquid can be suppressed, and particles having a small particle size and a sharp particle size distribution can be formed without classification, by suppressing an increase in the size of core particles.

Abstract: Toner of the present invention includes aggregated particles formed by aggregating at least resin particles, pigment particles, and wax particles in an aqueous medium in the presence of a water-soluble inorganic salt. The wax includes at least one selected from the following: ester wax that has an iodine value of not more than 25, a saponification value of 30 to 300, and an endothermic peak temperature (melting point) of 50° C. to 100° C. based on a DSC method; and wax that is obtained by a reaction of alkyl alcohol having a carbon number of 4 to 30, unsaturated polycarboxylic acid or its anhydride, and synthetic hydrocarbon wax, and has an acid value of 1 to 80 mgKOH/g and an endothermic peak temperature (melted point) of 50° C. to 120° C. based on the DSC method.

Abstract: Toner of the present invention is produced by mixing in an aqueous medium at least a resin particle dispersion in which resin particles are dispersed, a colorant particle dispersion in which colorant particles are dispersed, and a wax particle dispersion in which wax particles are dispersed and heating and aggregating the mixed dispersion. The main component of a surface-active agent used for the resin particle dispersion is a nonionic surface-active agent. The main component of at least one surface-active agent selected from a surface-active agent used for the wax particle dispersion and a surface-active agent used for the colorant particle dispersion is a nonionic surface-active agent. With this configuration, the toner can have a smaller particle size and a sharp particle size distribution without requiring a classification process.

Abstract: A toner is obtained in an aqueous medium by dispersing second resin particles into a core particles dispersion including at least first resin particles, and fusing the second resin particles with core particles. A second resin particle dispersion in which the second resin particles are dispersed is added after adjusting the pH value in the range of HS+2 to HS?5, where HS represents the pH value of the core particle dispersion in which the core particles are dispersed, so that toner particles have a volume-average particle size of 3 to 7 ?m, a content of the toner particles having a particle size of 2.52 to 4 ?m in a number distribution is 10 to 75% by number, the toner particles having a particle size of 4 to 6.06 ?m in a volume distribution is 25 to 75% by volume, and the toner particles having a particle size of not less than 8 ?m in the volume distribution is not more than 5% by volume.

Abstract: A toner of the present invention includes a first wax and a second wax. The endothermic peak temperature of the first wax by the DSC method is 50° C. to 90° C. The endothermic peak temperature of the second wax is 5° C. to 50° C. higher than that of the first wax. Jmw1/Jw1 is 0.5 or less and Jmw2/Jw2 is 0.5 to 1.2, where Jw1 represents the endotherm of the first wax, Jw2 represents the endotherm of the second wax, Jmw1 represents the melting endotherm of the first wax by the MDSC method, and Jmw2 represents the melting endotherm of the second wax. The first wax and the second wax are mixed into a dispersion beforehand, the dispersion is then mixed with a resin particle dispersion and a colorant particle dispersion, and the particles are aggregated to form core particles. Thus, a toner having a small particle size and a sharp particle size distribution can be produced without requiring a classification process.

Abstract: A toner or two-component developer is obtained by mixing, aggregating, and heating resin particles, colorant particles, and wax particles in an aqueous medium. A gel permeation chromatography (GPC) measurement of the resin particles shows that a weight-average molecular weight is 10000 to 60000, and the ratio of the weight-average molecular weight to a number-average molecular weight is 1.5 to 6. The wax particles include at least a first wax and a second wax. An endothermic peak temperature (melting point Tmw1 (° C.)) of the first wax based on a DSC method is 50° C. to 90° C. An endothermic peak temperature (melting point Tmw2 (° C.)) of the second wax based on the DSC method is at least 5° C. to 50° C. higher than Tmw1. Thus, the toner can have a smaller particle size and a sharp particle size distribution without requiring a classification process, can achieve a longer life, and can suppress transfer voids or scattering during transfer.

Abstract: The present invention provides toner containing core particles prepared by mixing and aggregating in an aqueous medium at least a first resin particle dispersion in which first resin particles are dispersed, a colorant particle dispersion in which particles of colorant are dispersed and a wax particle dispersion in which particles of wax are dispersed. The colorant contains carbon black having a DBP oil absorption of 45 to 70 (ml/100 g) and the wax contains a wax having an endothermic peak temperature (referred to as melting point Tmw1 (° C.)) according the DSC method of 50 to 90° C. It is thus possible to prepare toner that has a small particle size and a sharp particle size distribution without requiring a classification process and that can prevent transfer void and toner scattering during transfer and obtain high transfer efficiency. The present invention provides also a method for producing the toner.

Abstract: The present invention is a carrier for electrophotography in which a surface of at least a core material is coated with a resin, in which the coating resin contains a fluorine modified silicone resin and an aminosilane coupling agent, and in which the carrier charges a toner negatively. Consequently, a carrier with a high durability and a long lifetime for electrophotography is provided, in which the charge amount does not decrease at high temperature or high humidity nor extremely increase at low temperature or low humidity, in which a deterioration of a developing agent caused by stripping of a coating layer is prevented, and in which a deterioration caused by formation of spent toner of a toner is not caused.

Abstract: Toner includes aggregated and associated particles formed by mixing in an aqueous medium at least a resin particle dispersion in which resin particles are dispersed, a colorant particle dispersion in which colorant particles are dispersed, and a wax particle dispersion in which wax particles are dispersed and heat-treating the mixed dispersion for aggregation. The aggregated and associated particles include first particles having a capsule structure in which aggregated wax with an average particle size of greater than 1 ?m is incorporated into the resin, and second particles formed of the resin and the wax in a mixed and dispersed state. The toner can achieve oilless fixing that prevents offset without using oil while maintaining high OHP transmittance and also can eliminate spent of the toner components on a carrier to make the life longer.