Abstract: A toner comprising an external additive A, and a toner particle containing a binder resin and a colorant, wherein the external additive A: i) is an external additive that has a charge control agent on the surface thereof; ii) has a wall friction angle ? calculated from the following formula (1) of not more than 25.0° ?=?/5.0??formula (1); iii) has a number-average particle diameter (D1) of primary particles of at least 70 nm and not more than 500 nm; and iv) has a solidity as given by the following formula (2) of at least 0.40 and not more than 0.90 solidity=area of external additive A/area of region encompassed by envelope for external additive A?? formula (2).

Abstract: A toner comprising an external additive A, and a toner particle containing a binder resin and a colorant, wherein the external additive A: i) is an external additive that has a charge control agent on the surface thereof; ii) has a wall friction angle ? calculated from the following formula (1) of not more than 25.0° ?=?/5.0??formula (1); iii) has a number-average particle diameter (D1) of primary particles of at least 70 nm and not more than 500 nm; and iv) has a solidity as given by the following formula (2) of at least 0.40 and not more than 0.90 solidity=area of external additive A/area of region encompassed by envelope for external additive A?? formula (2).

Abstract: A toner comprising: a toner particle containing a toner base particle containing a binder resin and a colorant, and a resin particle fixed to a surface of the toner base particle; and an inorganic fine particle A, wherein the surface of the toner particle has protruded portions originating in the resin particle, an average length (D) of long sides of the protruded portions is 50 nm to 300 nm, an average Height (H) of the protruded portions is 25 nm to 250 nm, the average long-side length and the average height of the protruded portions satisfies a specific relationship, and an average value of a compactness of the inorganic fine particle A is 0.40 to 0.80, and the attachment rate of the inorganic fine particles A is 0.1% to 5.0% by area.

Abstract: A toner having compatibility between transfer properties and cleaning properties is provided. A toner wherein a fine particle A containing a primary particle having a number average particle diameter (D1) of 80 nm or more and 400 nm or less is present on the surface of a toner particle at a coverage ratio of 5 to 40%, a fixing rate of 30 to 90% by mass, and a variation coefficient of 0.1 to 0.5 in a region of 0.5 ??m2.

Abstract: A toner comprising: a toner particle containing a toner base particle containing a binder resin and a colorant, and a resin particle fixed to a surface of the toner base particle; and an inorganic fine particle A, wherein the surface of the toner particle has protruded portions originating in the resin particle, an average length (D) of long sides of the protruded portions is 50 nm to 300 nm, an average Height (H) of the protruded portions is 25 nm to 250 nm, the average long-side length and the average height of the protruded portions satisfies a specific relationship, and an average value of a compactness of the inorganic fine particle A is 0.40 to 0.80, and the attachment rate of the inorganic fine particles A is 0.1% to 5.0% by area.

Abstract: The toner comprising a toner particle containing a binder resin and a colorant, an iron oxide particle and an organic-inorganic composite fine particle, wherein the organic-inorganic composite fine particle comprises a vinyl resin particle, and inorganic fine particles which are embedded in the vinyl resin particle, and at least a part of which is exposed at surface of the organic-inorganic composite fine particle; the organic-inorganic composite fine particle has convexes derived from the inorganic fine particles, and wherein: a coverage ratio of the surface of the organic-inorganic composite fine particle with the inorganic fine particle is 20-70%; and the content of the iron oxide particle present on a surface of the toner particle is 0.1-5.0 mass % based on the mass of the toner particle.

Abstract: Provided is a magnetic toner in which enhancement of initial transfer efficiency and transfer efficiency that is stable during a long-term use are achieved by simultaneously suppressing the friction force between the toner and a drum and the cohesion between toners, and further the degradation in chargeability and fluidity caused by the deterioration of the toner. The magnetic toner includes: a magnetic toner particle; a first external additive; and a second external additive. The first external additive includes an organic-inorganic composite fine particle, a plurality of convexes derived from an inorganic fine particle being present on a surface of the organic-inorganic composite fine particle, and has a number-average particle diameter of 50 nm or more and 500 nm or less. The second external additive includes a silica fine particle and has a number-average particle diameter of 5 nm or more and 30 nm or less. A shear load calculated from a rotation torque is 0.50 kPa or more and 2.

Abstract: A toner is provided including large particle-diameter external additives with sweep to the concaves of a toner particle suppressed, so that the large particle-diameter external additives function as spacer particles for a long period. The toner includes toner particles which contain a binder resin and magnetic material, and organic-inorganic composite fine particles having a structure including inorganic fine particles embedded in a vinyl resin particle. The presence state of the magnetic material on the toner particle surface satisfies specific conditions and the presence state of the organic-inorganic composite fine particles on the toner surface satisfies specific conditions.

Abstract: Provided is a magnetic toner in which enhancement of initial transfer efficiency and transfer efficiency that is stable during a long-term use are achieved by simultaneously suppressing the friction force between the toner and a drum and the cohesion between toners, and further the degradation in chargeability and fluidity caused by the deterioration of the toner. The magnetic toner includes: a magnetic toner particle; a first external additive; and a second external additive. The first external additive includes an organic-inorganic composite fine particle, a plurality of convexes derived from an inorganic fine particle being present on a surface of the organic-inorganic composite fine particle, and has a number-average particle diameter of 50 nm or more and 500 nm or less. The second external additive includes a silica fine particle and has a number-average particle diameter of 5 nm or more and 30 nm or less. A shear load calculated from a rotation torque is 0.50 kPa or more and 2.

Abstract: The toner comprising a toner particle containing a binder resin and a colorant, an iron oxide particle and an organic-inorganic composite fine particle, wherein the organic-inorganic composite fine particle comprises a vinyl resin particle, and inorganic fine particles which are embedded in the vinyl resin particle, and at least a part of which is exposed at surface of the organic-inorganic composite fine particle; the organic-inorganic composite fine particle has convexes derived from the inorganic fine particles, and wherein: a coverage ratio of the surface of the organic-inorganic composite fine particle with the inorganic fine particle is 20-70%; and the content of the iron oxide particle present on a surface of the toner particle is 0.1-5.0 mass % based on the mass of the toner particle.

Abstract: A toner having compatibility between transfer properties and cleaning properties is provided. A toner wherein a fine particle A containing a primary particle having a number average particle diameter (D1) of 80 nm or more and 400 nm or less is present on the surface of a toner particle at a coverage ratio of 5 to 40%, a fixing rate of 30 to 90% by mass, and a variation coefficient of 0.1 to 0.5 in a region of 0.5 ??m2.

Abstract: A magnetic toner having a toner particle containing a binder resin and a magnetic member, a first inorganic fine particle and an organic-inorganic composite particle on the surface of the toner particle, wherein the organic-inorganic composite particle i) has a structure in which a second inorganic fine particle is embedded in a resin particle, and ii) is contained in an amount of 0.5 mass % or more and 3.0 mass % or less based on the mass of the toner; the first inorganic fine particle contains an inorganic oxide fine particle selected from the group consisting of a silica fine particle, a titanium oxide fine particle and an alumina fine particle; has a number average particle diameter (D1) of 5 nm or more and 25 nm or less, and contains the silica fine particle in an amount of 85 mass % or more based on the inorganic oxide fine particle.

Abstract: A toner is provided including large particle-diameter external additives with sweep to the concaves of a toner particle suppressed, so that the large particle-diameter external additives function as spacer particles for a long period. The toner includes toner particles which contain a binder resin and magnetic material, and organic-inorganic composite fine particles having a structure including inorganic fine particles embedded in a vinyl resin particle. The presence state of the magnetic material on the toner particle surface satisfies specific conditions and the presence state of the organic-inorganic composite fine particles on the toner surface satisfies specific conditions.

Abstract: A method of producing a magnetic carrier, having a coating process step in which a surface of a magnetic carrier core is coated with particles of a resin composition by a mechanical impact force. The coating process step has a first coating process step of mixing, dispersing, and fixing the particles on the surface of the core, and a second coating process step, which is performed after the first coating process step, of carrying out a film-forming coating process on the particles. In the first and second coating process steps, the peripheral velocity of the outermost end of stirring members, the coating process time, the product temperature at the end of the coating process, and the glass-transition temperature of the resin component satisfy specific relationships.

Abstract: A method of producing a magnetic carrier, having a coating process step in which a surface of a magnetic carrier core is coated with particles of a resin composition by a mechanical impact force. The coating process step has a first coating process step of mixing, dispersing, and fixing the particles on the surface of the core, and a second coating process step, which is performed after the first coating process step, of carrying out a film-forming coating process on the particles. In the first and second coating process steps, the peripheral velocity of the outermost end of stirring members, the coating process time, the product temperature at the end of the coating process, and the glass-transition temperature of the resin component satisfy specific relationships.

Abstract: When a surface of magnetic carrier core particles is coated with coating resin composition particles, the coating is conducted so that a surface of the magnetic carrier is free from cracks and chips and has fewer residual resin composition particles and a coating is uniform. In the method, a rotor having a plurality of stirring members on a surface thereof is rotated to coat the surface of magnetic carrier core particles with the resin composition particles. When the coating is conducted, while repeatedly conducting transportation in a direction of a driver and transportation in an anti-driver direction, the surface of the magnetic carrier core particles is coated with the resin composition. The resin composition particles has a 50% particle diameter (D50) based on volume of 0.2 ?m or more to 6.0 ?m or less and the proportion of particles of 10.0 ?m or more is 2.0% by volume or less.

Abstract: Provided are a magnetic carrier and a two-component developer comprising the magnetic carrier. The magnetic carrier comprises magnetic carrier particles, each of which comprises a magnetic carrier core, the surface of which is coated with a charge control agent and further coated with a resin coat layer containing a resin composition.

Abstract: A process for producing a toner with which toner particles can be highly conglobated, a toner that hardly causes fogging in an image, and an yield of toner is increased is provided. A process for producing a toner of the present invention comprises the step of simultaneously performing a surface modification and classification of particles by using a batch-wise surface modification apparatus, in which when a straight line extending from a central position S1 of a loading pipe in a direction of loading a raw material is denoted by L1 and a straight line extending from a central position O1 of the fine powder discharging pipe in a direction of discharging fine powder and ultra-fine powder is denoted by L2, an angle ? formed between the lines L1 and L2 is in a range of 210 to 330° with reference to the direction in which a classification rotor rotates.

Abstract: When a surface of magnetic carrier core particles is coated with coating resin composition particles, the coating is conducted so that a surface of the magnetic carrier is free from cracks and chips and has fewer residual resin composition particles and a coating is uniform. In the method, a rotor having a plurality of stirring members on a surface thereof is rotated to coat the surface of magnetic carrier core particles with the resin composition particles. When the coating is conducted, while repeatedly conducting transportation in a direction of a driver and transportation in an anti-driver direction, the surface of the magnetic carrier core particles is coated with the resin composition. The resin composition particles has a 50% particle diameter (D50) based on volume of 0.2 ?m or more to 6.0 ?m or less and the proportion of particles of 10.0 ?m or more is 2.0% by volume or less.

Abstract: A DC/DC converter includes a main switching element and a subordinate switching element, and is arranged to supply power to load via a coil. The ON-time of a subordinate switching element in a succeeding cycle is controlled based on a period of time tdif from the time when the subordinate switching element is turned off until the time when voltage at the point of connection of the two switching elements reaches a predetermined threshold value.