A roller charging device may include a Y-shaped electrically conductive brush and a screw terminal coupling the Y-shaped electrically conductive brush to a housing of the roller charging device and electrically coupling the Y-shaped electrically conductive brush to a power source. A printing fluid developer may include a plurality of rollers and a plurality of Y-shaped brushes to each contact one of the plurality of rollers wherein each of the Y-shaped brushes provides an electrical charge to each of the plurality of rollers.

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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A discharging method used in an image forming apparatus includes discharging, with an exposure device, an exposure range of the latent image bearer, and discharging, with a discharger, an area of the latent image bearer outside the exposure range and inside a developing range in a main scanning direction. The exposure range is inside the developing range in the main scanning direction. The discharging with the exposure device and the discharging with the discharger are performed when a rotation of the latent image bearer is stopped after a toner image is transferred from the latent image bearer.

A discharging method used in an image forming apparatus includes discharging, with an exposure device, an exposure range of the latent image bearer, and discharging, with a discharger, an area of the latent image bearer outside the exposure range and inside a developing range in a main scanning direction. The exposure range is inside the developing range in the main scanning direction. The discharging with the exposure device and the discharging with the discharger are performed when a rotation of the latent image bearer is stopped after a toner image is transferred from the latent image bearer.

A discharging light quantity adjusting device includes a potential measurement controller that performs: a process of causing a first toner image forming process to charge an image holding member to a first potential and an electrometer to measure an electrostatic potential on the image holding member to obtain a first value, a process of causing a second toner image forming process to charge the image holding member to a second potential and removing a toner image formed by the second toner image forming process, and a process of causing a third toner image forming process to charge the image holding member to a third potential, and causing the electrometer to measure an electrostatic potential on the image holding member to obtain a second value; and a light quantity adjusting unit that adjusts a quantity of a discharging light based on the first and second values.

A discharging light quantity adjusting device includes a potential measurement controller that performs: a process of causing a first toner image forming process to charge an image holding member to a first potential and an electrometer to measure an electrostatic potential on the image holding member to obtain a first value, a process of causing a second toner image forming process to charge the image holding member to a second potential and removing a toner image formed by the second toner image forming process, and a process of causing a third toner image forming process to charge the image holding member to a third potential, and causing the electrometer to measure an electrostatic potential on the image holding member to obtain a second value; and a light quantity adjusting unit that adjusts a quantity of a discharging light based on the first and second values.