Abstract: An image forming apparatus includes a positively-charged single layer type electrophotographic photoreceptor, a charging device with a contact charging roller for charging a surface of the photoreceptor and an exposure device for exposing the charged surface of the photoreceptor to light to form an electrostatic latent image thereon. A developing device develops the electrostatic latent image into a toner image and a transfer device transfers the toner image to a transferred body. The charging roller is made of electrically conductive rubber having an Asker-C rubber hardness of 62 to 81°. A roller surface roughness of the charging roller has an average distance (Sm) between asperity peaks on a cross-sectional curve of 55 to 130 ?m and that a ten-point average roughness (Rz) is 9 to 19 ?m. The image forming apparatus is capable of preventing carrier trapping, film peeling and uneven charging in the photoreceptor.

Abstract: An image-forming apparatus is equipped with a neutralization light source that is disposed between a primary transfer position and the cleaning unit, in a direction of rotation of the first image carrier that composes the image-forming unit; irradiates a first neutralization light from a position opposing the primary transfer position on a first image carrier up to a position opposing the cleaning unit; and irradiates a second neutralization light from a position opposing the developer unit for a second image carrier that composes an image-forming unit disposed adjacent to the image-forming unit at a downstream side in the direction of transfer belt rotation, up to a position opposite the primary transfer position.

Abstract: The present invention provides an image forming apparatus and an image forming method capable of preventing excessive charging in the toner within the cleaning device for effectively preventing generation of the black spots derived from the leak current. In the image forming apparatus comprising a cleaning device having a cleaning blade for scraping out the toner on a latent image carrier body surface and the image forming method using the same, the toner contains a titanium oxide as an additive agent, and with the premise that the fluorescence X ray intensity of the titanium oxide added to the toner before use is X1, and the fluorescence X ray intensity of the titanium oxide added to the toner within the cleaning device is X2, X1 and X2 satisfy the following relationship formula (1): X2/X1?1.2??(1).

Abstract: A cleaning apparatus 30 is provided with a cleaning roller 33 that is a rotating member, a scraper 35, a partition wall 36, opening/closing members 37, and a discharge screw 38 that is a discharging member. The scraper 35 supported by the partition wall 36 scrapes toner by bringing the tip thereof into contact with the cleaning roller 33. The partition wall 36 has a plurality of openings 36a, and partitions between a space S1 formed on an upstream side of the cleaning roller 33 in a rotation direction of a drum and a space S2 in which the discharge screw 38 is provided. The opening/closing members 37 are individually provided for the openings 36a so as to permit toner to move through the openings 36a only in a direction from the space S1 to the space S2. With this structure, it is possible to make toner present in the vicinity of the cleaning roller 33 smoothly move toward the discharge screw 38.

Abstract: The invention provides an image forming apparatus that, even when a dynamic friction coefficient of a latent image carrier has a value more than a predetermined value, can prevent a toner in the cleaning device from excessively charging and an air gap from occurring while efficiently recovering a residual toner while efficiently recovering a residual toner, and thereby can effectively prevent the black spots due to the leakage current from the cleaning device from occurring; and an image forming method therewith. There are provided an image forming apparatus that includes a cleaning device provided with a rotation member for cleaning a surface of a latent image carrier with a titanium oxide contained in a toner and an image forming method therewith, wherein a dynamic friction coefficient of the latent image carrier is set to a value in the range of 0.3 to 0.7 and a specific resistance of the titanium oxide is set to a value in the range of 1×100 to 1×102 ?·cm.

Abstract: The invention provides an image forming apparatus that, even when a downward transfer method is adopted, can prevent a toner in a cleaning device from excessively charging and an air gap from occurring, and thereby can effectively suppress occurrence of black spots due to a leakage current from the cleaning device, and an image forming method therewith. Provided are an image forming apparatus includes a latent image carrier for transferring a toner carried on a surface thereof from downward to a transfer body; and a cleaning device provided with a rotation member for cleaning the surface of the latent image carrier, a resistance of an elastic layer formed on an outer periphery part of the rotation member being set to a value in the range of 1×102 to 1×107?, and an image forming method.

Abstract: The present invention provides an image forming apparatus and an image forming method capable of preventing excessive charging in the toner within the cleaning device for effectively preventing generation of the black spots derived from the leak current. In the image forming apparatus comprising a cleaning device having a cleaning blade for scraping out the toner on a latent image carrier body surface and the image forming method using the same, the toner contains a titanium oxide as an additive agent, and with the premise that the fluorescence X ray intensity of the titanium oxide added to the toner before use is X1, and the fluorescence X ray intensity of the titanium oxide added to the toner within the cleaning device is X2, X1 and X2 satisfy the following relationship formula (1): X2/X1?1.

Abstract: In electrophotographic image formation, a contact charging member, to which a square AC superimposed voltage is applied, is contacted with a positive-charged organic photosensitive member comprising a single photoconductive layer comprising charge generating material, hole transporting material, electron transporting material, and organic binders, so as to contact charge the positive-charged organic photosensitive member.

Abstract: A cleaning apparatus 30 is provided with a cleaning roller 33 that is a rotating member, a scraper 35, a partition wall 36, opening/closing members 37, and a discharge screw 38 that is a discharging member. The scraper 35 supported by the partition wall 36 scrapes toner by bringing the tip thereof into contact with the cleaning roller 33. The partition wall 36 has a plurality of openings 36a, and partitions between a space S1 formed on an upstream side of the cleaning roller 33 in a rotation direction of a drum and a space S2 in which the discharge screw 38 is provided. The opening/closing members 37 are individually provided for the openings 36a so as to permit toner to move through the openings 36a only in a direction from the space S1 to the space S2. With this structure, it is possible to make toner present in the vicinity of the cleaning roller 33 smoothly move toward the discharge screw 38.