Abstract: The present invention provides a developing apparatus and an image forming apparatus which are capable of outputting stable images with no surface staining and toner scattering even when an image forming process is repeated over a long time period, or even when image formation is performed after special use conditions in which little toner is consumed have continued over a long time period. An area in which a relationship of 0.6<Vlocal/Vaverage<0.

Abstract: An image forming apparatus includes an image carrier; an exposing unit that exposes the image carrier to light to form an electrostatic latent image on the image carrier; a developing unit that has at least a toner, and develops the electrostatic latent image formed on the image carrier as a toner image; a transfer unit that transfers the toner image onto a recording medium; a fixing unit that fixes the toner image transferred on the recording medium; an exposure-energy modulating unit that modulates exposure energy of the exposing unit; and a development-time detecting unit that detects operation time of the developing unit. The exposure-energy modulating unit modulates the exposure energy based on a result of detection by the development-time detecting unit.

Abstract: An apparatus for developing a latent image on a latent image carrier includes a toner carrier and multiple electrodes arranged at intervals on a surface of the toner carrier. A potential difference is formed between even-numbered electrodes and odd-numbered electrodes of the electrodes by applying a first pulse voltage to the even-numbered electrodes and a second pulse voltage to the odd-numbered electrodes so that toner on the surface of the toner carrier moves back and forth between the electrodes, where the first and second pulse voltages are in different phases, and the toner moving back and forth between the electrodes is conveyed to a position facing the latent image carrier by movement of the surface of the toner carrier and thereby caused to adhere to the latent image on the latent image carrier.

Abstract: An image forming apparatus equipped with an image bearing member, a latent electrostatic image forming unit which forms a latent electrostatic image on the image bearing member, a developing unit which develops the latent electrostatic image by using a toner to form a toner image, a transfer fixing member 13 which is roll shaped or belt shaped and bears the toner image T, a heating unit 15 which heats the toner image on the transfer fixing member; and a pressurizing member 14 which is roll shaped and forms a transfer fixing nip N with the transfer fixing member. And the toner image T on the transfer fixing member is transferred and fixed simultaneously to a recording medium P which passes through the transfer fixing nip to record an image on the recording medium.

Abstract: A multi color image forming apparatus includes a plurality of stations arranged side by side for forming unique mono-color toner images using mono-color developers each having a different mono-color toner. Each of the plurality of stations includes an image bearing member for bearing a latent image, and a developing device for visualizing the latent image into the mono-color toner image. A conveying device is provided to convey a transfer medium. A transfer device is provided to transfer the mono-color toner images from the image bearing members to the transfer medium. Charge ability of prescribed mono-color toner included in the mono-color developer used in the upstream station is smaller than that used in the downstream station.

Abstract: A multi color image forming apparatus includes a plurality of stations arranged side by side for forming unique mono-color toner images using mono-color developers each having a different mono-color toner. Each of the plurality of stations includes an image bearing member for bearing a latent image, and a developing device for visualizing the latent image into the mono-color toner image. A conveying device is provided to convey a transfer medium. A transfer device is provided to transfer the mono-color toner images from the image bearing members to the transfer medium. Charge ability of prescribed mono-color toner included in the mono-color developer used in the upstream station is smaller than that used in the downstream station.

Abstract: An image forming apparatus includes a plurality of color toner development devices, a recycled toner development device, at least one cleaning device, a toner collecting and supplying device, and an image pattern generation device. The plurality of color toner development devices store separate color toners, and the recycled toner development device stores recycled toner. The at least one cleaning device removes toner remaining on at least one image carrying member after a transfer operation. The toner collecting and supplying device stores and supplies the removed toner to the recycled toner development device. The image pattern generation device generates image patterns developed by the plurality of color toner development devices and the recycled toner development device based on a characteristic of developer and a color of the recycled toner stored in the recycled toner development device.

Abstract: An apparatus including and a method using a fixing device including a fixing member, a pressure member, a heater, and a pressure controller. The fixing member and the pressure member face with each other to form a nip. The heater heats a surface of the fixing member when the fixing member rotates. The pressure controller is configured to change a pressure generated at the nip, according to an operation of the fixing device.

Abstract: An image forming apparatus includes an image carrier; an exposing unit that exposes the image carrier to light to form an electrostatic latent image on the image carrier; a developing unit that has at least a toner, and develops the electrostatic latent image formed on the image carrier as a toner image; a transfer unit that transfers the toner image onto a recording medium; a fixing unit that fixes the toner image transferred on the recording medium; an exposure-energy modulating unit that modulates exposure energy of the exposing unit; and a development-time detecting unit that detects operation time of the developing unit. The exposure-energy modulating unit modulates the exposure energy based on a result of detection by the development-time detecting unit.

Abstract: An image forming apparatus includes a pseudo half tone processing unit that performs a pseudo half tone process on input image data to generate output image data. An exposure unit executes light modulation of a plurality of light emitting sources based on the output image data. The exposure unit performs writing in such a way that different numbers of light emitting sources are used when writing a character/line image and a picture image or a graphics image. The pseudo half tone processing unit performs pseudo half tone processes with different resolutions on a character/line image and a picture image or a graphics image based on the numbers of the light emitting sources to be used for the writing by the exposure unit.

Abstract: A developing method of the present invention uses a sleeve accommodating a stationary magnet roller formed with a plurality of magnetic poles and facing an image carrier. The sleeve is rotated to convey a developer, which is made up of toner grains and magnetic carrier grains and deposited on the sleeve, to a developing zone for thereby feeding the toner grains from a magnet brush formed by the developer to a latent image formed on the image carrier. When the developing zone is seen from the image carrier side, the ratio of the total area of voids present at the tips of the magnet brush to the total area of the developing zone is selected to be 25% or less.

Abstract: A developing method of the present invention uses a sleeve accommodating a stationary magnet roller formed with a plurality of magnetic poles and facing an image carrier. The sleeve is rotated to convey a developer, which is made up of toner grains and magnetic carrier grains and deposited on the sleeve, to a developing zone for thereby feeding the toner grains from a magnet brush formed by the developer to a latent image formed on the image carrier. When the developing zone is seen from the image carrier side, the ratio of the total area of voids present at the tips of the magnet brush to the total area of the developing zone is selected to be 25% or less.

Abstract: The development is performed under a condition that |Q2|−|Q1|/|Q1≦±0.45. Here, Q1 denotes an average amount of charge on toner held on a development roller and carried toward a development region immediately before development. Q2 denotes an average amount of charge on toner immediately before development held and carried toward the development region in the state immediately after development of an electrostatic latent image on a development drum. This is effective to allow the amount of charge q/m on toner held on the development roller to have a variation rate of 45% or below and an afterimage rate R within 2%.

Abstract: The development is performed under a condition that |Q2|−|Q1|/|Q1≦±0.45. Here, Q1 denotes an average amount of charge on toner held on a development roller and carried toward a development region immediately before development. Q2 denotes an average amount of charge on toner immediately before development held and carried toward the development region in the state immediately after development of an electrostatic latent image on a development drum. This is effective to allow the amount of charge q/m on toner held on the development roller to have a variation rate of 45% or below and an afterimage rate R within 2%.