Provided is an electrophotographic photoreceptor, which is excellent in abrasion resistance and scratch resistance, has excellent electrical characteristics, and is capable of inhibiting an image defect, a manufacturing method of an electrophotographic photoreceptor, a process cartridge, and an electrophotographic apparatus. A surface layer of the electrophotographic photoreceptor contains a copolymer of a composition which contains resin particles containing fluorine atoms, a charge transport compound having 2 or more polymerizable functional groups, a compound represented by General Formula (1), and a resin having a structure represented by General Formula (2) and a structure represented by General Formula (3). The polymerizable functional groups t are independently selected from an acryloyloxy group and a methacryloyloxy group, and a content of the compound represented by General Formula (1) in the composition is 0.10% by mass or more.

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Provided is an electrophotographic photoreceptor, which is excellent in abrasion resistance and scratch resistance, has excellent electrical characteristics, and is capable of inhibiting an image defect, a manufacturing method of an electrophotographic photoreceptor, a process cartridge, and an electrophotographic apparatus. A surface layer of the electrophotographic photoreceptor contains a copolymer of a composition which contains resin particles containing fluorine atoms, a charge transport compound having 2 or more polymerizable functional groups, a compound represented by General Formula (1), and a resin having a structure represented by General Formula (2) and a structure represented by General Formula (3). The polymerizable functional groups t are independently selected from an acryloyloxy group and a methacryloyloxy group, and a content of the compound represented by General Formula (1) in the composition is 0.10% by mass or more.

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An image forming device is provided. The image forming device may include a transfer belt to move in a preset direction, a plurality of image generators to respectively generate a toner image on the transfer belt, and a controller to output an image generation signal to each of the plurality of image generators such that the plurality of image generators respectively generate a toner image. A plurality of toner images generated using the plurality of image generators are arranged on the transfer belt in parallel to each other, and an arrangement order of the plurality of toner images is identical to an arrangement order of the plurality of image generators.

An image forming device is provided. The image forming device may include a transfer belt to move in a preset direction, a plurality of image generators to respectively generate a toner image on the transfer belt, and a controller to output an image generation signal to each of the plurality of image generators such that the plurality of image generators respectively generate a toner image. A plurality of toner images generated using the plurality of image generators are arranged on the transfer belt in parallel to each other, and an arrangement order of the plurality of toner images is identical to an arrangement order of the plurality of image generators.

An image forming apparatus includes a unit configured to perform image forming operation, a unit board in the unit, a wiring configured to be connected to the unit board, and a control board configured to be connected to the unit board with the wiring and control the unit. The unit board includes a connector to which the wiring is to be connected. A length of the connector in a longitudinal direction of the connector is longer than a length of the unit board in a widthwise direction of the unit board, and the longitudinal direction of the connector intersects the widthwise direction of the unit board.

An image forming apparatus includes a unit configured to perform image forming operation, a unit board in the unit, a wiring configured to be connected to the unit board, and a control board configured to be connected to the unit board with the wiring and control the unit. The unit board includes a connector to which the wiring is to be connected. A length of the connector in a longitudinal direction of the connector is longer than a length of the unit board in a widthwise direction of the unit board, and the longitudinal direction of the connector intersects the widthwise direction of the unit board.

A carrier core material formed with ferrite particles, the skewness Rsk of the particle is equal to or more than 0.40 but equal to or less than 0.20, and the kurtosis Rku of the particle is equal to or more than 3.20 but equal to or less than 3.50. Here, the maximum height Rz of the particle is equal to or more than 2.20 m but equal to or less than 3.50 m. Moreover, the ferrite particle contains at least either of Mn and Mg elements. In this way, cracking or chipping in a concave-convex portion of a particle surface is unlikely to occur, and moreover, the amount of coating resin used can be reduced without properties such as electrical resistance being lowered.

A carrier core material formed with ferrite particles, the skewness Rsk of the particle is equal to or more than 0.40 but equal to or less than 0.20, and the kurtosis Rku of the particle is equal to or more than 3.20 but equal to or less than 3.50. Here, the maximum height Rz of the particle is equal to or more than 2.20 m but equal to or less than 3.50 m. Moreover, the ferrite particle contains at least either of Mn and Mg elements. In this way, cracking or chipping in a concave-convex portion of a particle surface is unlikely to occur, and moreover, the amount of coating resin used can be reduced without properties such as electrical resistance being lowered.

An image forming device is provided. The image forming device may include a transfer belt to move in a preset direction, a plurality of image generators to respectively generate a toner image on the transfer belt, and a controller to output an image generation signal to each of the plurality of image generators such that the plurality of image generators respectively generate a toner image. A plurality of toner images generated using the plurality of image generators are arranged on the transfer belt in parallel to each other, and an arrangement order of the plurality of toner images is identical to an arrangement order of the plurality of image generators.

A toner is provided. The toner includes a crystalline resin and a non-crystalline resin, and has a thermal property such that when the toner is heated after being firstly heated to 60 C. followed by cooling in differential scanning calorimetry (DSC), the toner has a clear peak specific to melting of the crystalline resin at a temperature T1, and when the toner is heated after being firstly heated to 80 C. followed by cooling in the differential scanning calorimetry (DSC), the toner does not have a clear peak specific to melting of the crystalline resin at a temperature not higher than the temperature T1.