Sharp Kabushiki Kaisha Corporation

Takayuki Yamanaka

Atsushi Inoue

Eiichi Kido

Hiroshi Tatsumi

Tadashi Iwamatsu

Nobuyuki Azuma

Jitsuo Masuda

Takashi Sakai

Masanori Yamada

Toshihiko Takaya

Kazuhiro Matsuyama

Masahiro Sakai

Hiroaki Nakaya

Tetsuro Toyoshima

Yuichi Kazaki

Hideaki Fujita

Toshihide Ohgoshi

Toshiaki Ino

Takashi Kitagawa

Shigeyuki Wakada

Keiji Yasuda

Hiroshi Ishii

Toshio Yamanaka

Masanori Matsumoto

Hideaki Kadowaki

Katsumi Adachi

Junichi Saito

Taisuke Kamimura

Koichi Toriyama

Kotaro Fukushima

Takanori Kamoto

Yukihito Nishio

Hiroaki Yoshida

Masayasu Narimatsu

Nobuhiko Nakano

Mitsuyoshi Terada

Osamu Wada

Nobuyuki Yoshioka

Kouji Shinkawa

Hideji Saikoh

Kaori Dakeshita

Junji Morimoto

Tetsuyuki Ueda

Kaori Fujii

Mikie Kobayashi

A method for producing a low density resin-coated carrier having a small resin amount to a carrier core material and having a uniform resin coating layer formed on the carrier core material is provided. A resin-coated carrier has a carrier core material and a resin coating layer formed on the surface of the carrier core material. The carrier core material has pores and an apparent density of 1.6 g/cmto 2.0 g/cmand a remanent magnetization of 10 emu/g of less. The resin coating layer is formed by a dry process of adhering resin particles to a surface of the carrier core material and applying heat and impact force to the resin particles. A volume average particle size of the resin particles is less than 1 &#x3bc;m. A two-component developer containing the resin-coated carrier is charged in a developing device in an image forming apparatus, and an image is formed.

Method for producing resin-coated carrier, resin-coated carrier, two-component developer, developing device, image forming apparatus and image forming method

The present invention therefore provides an image forming apparatus, comprising: a photoconductor; a charge means for charging the photoconductor; an exposure means for irradiating a surface of the photoconductor with light to form an electrostatic latent image; a development means for developing the electrostatic latent image formed; a transfer means for transferring the image developed onto a paper sheet; and a discharge means for irradiating the surface of the photoconductor with light to eliminate charges, wherein the photoconductor contains a titanylphthalocyanine having absorption bands in a wavelength region of 380 nm to 420 nm and a wavelength region of 600 nm to 850 nm as a charge generation material, the exposure means irradiates the surface of the photoconductor with light having a wavelength of 380 nm to 420 nm to form the electrostatic latent image, and the discharge means irradiates the surface of the photoconductor with light having a wavelength of 600 nm to 850 nm to eliminate the charges.

Image forming apparatus having a photoconductor containing titanylphthalocyanine

An image forming apparatus includes: a latent image bearing member on which an electrostatic latent image is to be formed; a developing unit which contains the developer and performs a development process to develop the electrostatic latent image formed on the latent image bearing member; and a movement mechanism which moves the developing unit toward the latent image bearing member when the development process is performed, and moves the developing unit away from the latent image bearing member and changes the attitude of the developing unit with, respect to the latent image bearing member when the development process is not performed.

Image forming apparatus with movable developing unit

One embodiment of an image forming apparatus according to the present invention includes an image forming apparatus provided with a one-component development apparatus having a toner layer regulating blade for regulating a thickness of a toner layer on a surface of a developer bearing member that contacts a photosensitive body, wherein at a non-development time after completion of operation of the developer bearing member, the developer bearing member is caused to rotate slightly in a direction reverse to that during development.

Image forming apparatus provided with one-component development apparatus

An developing device in which a developing roller develops an electrostatic latent image on a photo conductor; a developing roller driving unit rotates the developing roller in a forward direction and in a backward direction respectively while development is performed and not performed; a thickness regulating member, which is pressed against a surface of the developing roller, regulates a thickness of developer adhered to the surface of the developing roller; and a suppression unit suppresses a pressing force of the thickness regulating member when the developing roller is rotating in the backward direction.

Developing device having thickness regulating member and image forming apparatus

A developing device includes a developer tank, a developing roller, a supply roller, a stirring member, and a doctor blade. The developing device is provided with: a cleaning member detachably provided on a contact portion of the doctor blade with the developing roller, which slides to rub a surface of the doctor blade upon contacting; a supporting section for supporting the cleaning member so as to be capable of being attached to and detached from the contact portion of the doctor blade with the developing roller; and a driving mechanism for moving the cleaning member so as to be attached to and detached from the contact portion of the doctor blade with the developing roller.

Developing device for prevention of coagulate toner adherence and image forming apparatus using the developing device

Before replacement of constituent parts of an image density sensor or of other image forming units, the image density of a formed test toner patch image is detected by the image density sensor and conditions for image formation are controlled. After replacement of the constituent parts, the image density sensor detects the image density of a test toner patch image which is formed based on the controlled conditions for image formation. The optical output and/or the optical sensitivity is adjusted so that a detected value becomes a predetermined reference value, to calibrate the image density sensor. With this image formation controlling method, the image density sensor can be calibrated easily and precisely, the image density of a toner pattern image can be held proper and a stable high-quality image can be obtained.

Image formation controlling method and image forming apparatus

An optical electric charge removal device mountable on an image formation apparatus of an electrophotographic system for removing residual charges on a photosensitive member by light irradiation is provided. The optical electric charge removal device includes a point light source provided in the image formation apparatus; and an optical conductor, mountable on a process cartridge which is detachable from the image formation apparatus, for guiding light incident from the point light source to the photosensitive member.

Optical electric charge removal device and image formation apparatus including the same

A developing apparatus capable of supplying a uniform thin layer of toner and of preventing toner scattering and leakage is provided, where the developing apparatus includes a supply roller for supplying toner to an outer peripheral surface of a toner carrier, the toner carrier for transferring the supplied toner by rotation and a layer thickness controlling member for controlling a thickness of the layer of the supplied toner at a predetermined value while making slide contact with the outer peripheral surface of the toner carrier via the toner, wherein the thin toner layer is supplied to an electrostatic latent image on an image carrier. The layer thickness controlling member is formed of an elastic plate to have a bent portion convex toward the toner carrier. The layer thickness controlling member is held by sealing members so that the bent portion makes elastic contact with the toner carrier outer peripheral surface over a nearly entire length of the toner carrier.

Developing apparatus

In image forming apparatuses producing recycled toner from residual toner and recycling the recycled toner, the toner composition changes, and the toner properties worsen, because the external additive contained in the collected residual toner that is collected with a cleaning portion decreases during the image formation. The residual toner that has been collected with the cleaning portion is conveyed through a conveyance path to a collected residual toner storage, and external additive is supplemented from an external additive cartridge, and mixed with being stirred to produce recycled toner. In a fresh toner storage, fresh toner and recycled toner are stirred, and when the amount of toner in a developing portion drops below a predetermined amount, toner is conveyed from the fresh toner storage through a conveyance path to the developing portion. The toner that has been conveyed to the developing portion is supplied to a photosensitive drum.

Image forming apparatus including system for recycling toner

A developing device, includes; a developing roller supporting and conveying mono component toner to a photoreceptor having a static latent image; a supplying roller pressed against the developing roller and rotated so as to supply the toner to the developing roller. In order to perform beneficial supply of the toner to the developing roller, bias voltages are applied so as to generate an electric field which will cause the toner between the developing roller and the supplying roller to be attracted to the developing roller. At a predetermined time before completion of development, the bias voltage applied to the supplying roller is switched so as to create an electric field which will cause the toner to be attracted to the supplying roller. Thus the toner residing between the developing roller and supplying roller after development is removed, whereby it is possible to prevent toner from sticking to that area on the developing roller, after development. Another configuration further includes a cleaning roller abutted on the supplying and regulating rollers. When development is completed, rotation of the developing roller is stopped. In time with this, the supplying roller, regulating roller and cleaning roller are kept on rotating for a predetermined period while the bias voltages are switched so that the direction of the electric fields acting on the toner, formed between the rollers after switching are opposite to those formed during development.

Image developing device using a toner as a developer

A cleaning element is arranged on the backside of the toner layer metering blade, i.e., the side opposite to the surface in contact with the developer support, in order to prevent the cleaning element from damaging the blade surface and the abutment surface of the metering blade against the developer support. This cleaning element is frictionally moved across the backside of the toner layer metering blade to remove stuck toner from the toner layer metering blade or prevent occurrence of buildups.

Developer unit with cleaning element

The image forming portion of this image forming apparatus includes a LSU, a photosensitive drum, a developing unit holder, a multiple number of developing units, an intermediate transfer element, a transfer element and a fixing unit. All the developing units are of an identical configuration. Therefore, for replacement of developing units, the operator may and should remove any color of developing unit in the same fashion and attach a fresh developing unit of the color in the same fashion. The image forming portion sets up the image forming conditions for individual colors in the developing order.

Image forming apparatus

In a mono component toner developing device, a developing roller supporting and conveying the mono component toner is arranged in contact with a photoreceptor supporting a static latent image. A supplying roller is arranged opposing the developing roller with a predetermined contact depth. The supplying roller has a pair of driven gears fixed at both ends of the rotational shaft thereof for being rotated so as to be meshed with a pair of driving gears rotated by a driving motor. The rotational force of the driving gears, acting at a coupling position, is used to deflect the supplying roller toward the developing roller side, whereby the supplying roller is pressed in approximately uniform contact with the developing roller across its full length along the shaft.

Toner developing device for an image forming apparatus

A developing unit having an elastic blade which is provided with rectangular holes along the width in the area between its abutment portion against a developing roller and the supported end.

Developing unit having elastic blade

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Nara, Japan

Takayuki Yamanaka