Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Yasuhito Yuasa

Noriaki Hirota

Masahisa Maeda

Hidekazu Arase

Mamoru Soga

Hideki Tatematsu

Akinori Toyoda

Futoshi Deguchi

Tetsuya Uemura

Kazumasa Hayashi

Koreaki Nakata

Tsuyoshi Itagoshi

Akihiro Okuma

Kiminori Umeda

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.

Power transmitting device, electronic equipment and wireless power transmission system

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 Tmw(&#xb0; C.)) of the first wax based on a DSC method is 50&#xb0; C. to 90&#xb0; C. An endothermic peak temperature (melting point Tmw(&#xb0; C.)) of the second wax based on the DSC method is at least 5&#xb0; C. to 50&#xb0; C. higher than Tmw. 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.

Toner, process for producing toner, and two-component developing agent

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. Third toner of the present invention includes aggregated particles including at least first resin particles and pigment particles, and colored particles having a finely roughened surface formed by fusing at least part of third resin particles and at least part of fourth resin particles on the surface of the aggregated particles. When the aggregated particles are formed in an aqueous medium, the pH is controlled in the specified range. The toner can achieve oilless fixing that prevents offset without using oil while maintaining high OHP transmittance. Therefore, it is possible to eliminate the spent of toner components on a carrier and to make the life longer. Moreover, thinning or scattering during transfer can be suppressed, thus ensuring high transfer efficiency.

Toner, method for producing toner, two component developer, and image forming apparatus

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&#xb0; C. to 90&#xb0; C. The relationship between an endothermic peak temperature (melting point Tmw2) of the second wax based on the DSC method and Tmw1 is expressed as 5+Tmw1 (&#xb0; C.)&#x2266;Tmw2 (&#xb0; C.)&#x2266;50+Tmw1 (&#xb0; C.).

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.

Toner, two-component developer, and image forming method

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&#xb0; C. to 100&#xb0; 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&#xb0; C. to 120&#xb0; C. based on the DSC method. The toner and a two-component developer can achieve oilless fixing that prevents offset without using oil while maintaining high OHP transmittance, can eliminate spent of the toner components on a carrier to make the life longer, and can ensure high transfer efficiency by suppressing transfer voids or scattering during transfer.

Toner, method for producing toner, two-component developer, and image forming apparatus

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. The toner and a two-component developer can achieve oilless fixing, eliminate spent of the toner components on a carrier to make the life longer, and ensure high transfer efficiency by suppressing transfer voids or scattering during transfer.

Toner, process for producing toner, two-component developer and image forming apparatus

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.

Two-component developer having a resin coated carrier for electrophotography and toner

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 &#x3bc;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.

Toner and two-component developer

Toner includes aggregated particles including at least resin particles, pigment particles, and wax particles. A fused film of the resin is formed on the surface of the toner. The wax is at least one selected from A: 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&#xb0; C. to 100&#xb0; C. based on a DSC method; and B: 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 unsaturated hydrocarbon wax and has an acid value of 1 to 80 mgKOH/g and an endothermic peak temperature (melted point) of 50&#xb0; C. to 120&#xb0; C. based on the DSC method. The toner and a two-component developer can achieve oilless fixing that prevents offset without using oil while maintaining high OHP transmittance, can eliminate spent of the toner components on a carrier to make the life longer, and can ensure high transfer efficiency by suppressing transfer voids or scattering during transfer.

Toner, process for producing the same, two-component developing agent and method of image formation

In an electrophotographic apparatus, which forms a color image by transferring a plurality of toner images having different colors onto an image-receiving sheet so as to be stacked and fixed thereon, even in the case of carrying out an oil-less fixing process and allowing the process speed to vary within wide range, the present invention provides a binder resin, toner and an electrophotographic apparatus which make it possible to achieve both superior fixing property and anti-offset property, and consequently to form a color image with high color reproducibility and high quality. In the present invention, a toner comprising a molecular weight maximum peak in a range of molecular weights from 2&#xd7;10to 3&#xd7;10in molecular weight distribution of GPC chromatogram, and a molecular weight maximum peak or shoulder in a range from 3&#xd7;10to 1&#xd7;10, wherein said molecular weight maximum peak or shoulder located on a range of molecular weights from 3&#xd7;10to 1&#xd7;10is obtained by kneading a toner composition containing a specific binder resin containing a high molecular weight component at not less than a specific amount so that the high molecular weight component of the binder is converted into a low molecular weight component by thermal or mechanical energy exerted at the time of kneading, is provided.

Binding resin for toner, toner and electrophotographic apparatus

Toner of the present invention at least includes binder resin, a colorant, and an external additive, wherein a loss modulus G&Prime;t (frequency: 10 rad/s) of the toner at 170&deg; C. satisfies 100&lE;G&Prime;t&lE;5000 (Pa), a storage modulus G&prime;t (frequency: 10 rad/s) of the toner at 190&deg; C. satisfies 10&lE;G&prime;t&lE;3000 (Pa), and the toner contains 5 to 50% by number of toner particles with a size of 2&times;10 to 5&times;10 m in size distribution of the toner.

Toner and electrophotographic method

In an electrophotographic apparatus, which forms a color image by transferring a plurality of toner images having different colors onto an image-receiving sheet so as to be stacked and fixed thereon, even in the case of carrying out an oil-less fixing process and allowing the process speed to vary within wide range, the present invention provides a binder resin, toner and an electrophotographic apparatus which make it possible to achieve both superior fixing property and anti-offset property, and consequently to form a color image with high color reproducibility and high quality. In the present invention, a toner comprising a molecular weight maximum peak in a range of molecular weights from 2&times;10 to 3&times;10 in molecular weight distribution of GPC chromatogram, and a molecular weight maximum peak or shoulder in a range from 3&times;10 to 1&times;10 , wherein said molecular weight maximum peak or shoulder located on a range of molecular weights from 3&times;10 to 1&times;10 is obtained by kneading a toner composition containing a specific binder resin containing a high molecular weight component at not less than a specific amount so that the high molecular weight component of the binder is converted into a low molecular weight component by thermal or mechanical energy exerted at the time of kneading, is provided.

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Katano, Japan

Yasuhito Yuasa