Ricoh Company, Ltd.

Takayuki Koike

Nobutaka Takeuchi

Junichi Matsumoto

Nobuo Iwata

Satoshi Muramatsu

Eriko Maruyama

Hajime Oyama

Hiromitsu Takagaki

Satoshi Mochizuki

Koji Suzuki

Hiroshi Yamashita

Hiroaki Matsuda

Masahide Yamashita

Tadashi Kasai

Masanori Suzuki

Yasuaki Iwamoto

Mitsuo Aoki

Yutaka Takahashi

Yohichiroh Watanabe

Tsunemi Sugiyama

Akihiro Itoh

Naohito Shimota

Takuya Saito

Tomio Kondou

Takeshi Takada

Kohsuke Suzuki

Tomomi Tamura

Kazuyuki Yazaki

An image forming apparatus of the present invention includes a developing unit for developing a latent image formed on an image carrier with a two-ingredient type developer, i.e., a toner and carrier mixture. A toner replenishing device replenishes toner stored in a toner storing portion to the developing unit. A carrier storing portion, storing a carrier therein, is constructed independently of the toner storing portion. The carrier is fed from the carrier storing portion to the developing unit by a toner conveying force available with the toner replenishing device.

Image forming apparatus including a developer replenishing device which uses an air feeding device for a two-ingredient type developer

An image forming apparatus, using a developer including toner particles and carrier particles, includes a developing unit, a cleaning unit, and a conveying unit. The developing unit contains the developer and develops an electrostatic latent image formed on an image carrying member as a toner image with the toner particles. The cleaning unit contains the developer and mixes the developer with the toner particles collected from the image carrying member after transferring the toner image. The conveying unit conveys a mixture of the collected toner particles and the developer from the cleaning unit to the developing unit.

Image forming apparatus and process cartridge therefore having a cleaner section which stores unused developer

Image forming apparatus including a developer replenishing device for a two-ingredient type developer

Image forming method and apparatus having a unit for conveying toner and carrier particles from a cleaning unit to a developing unit

A developing apparatus for use in an image forming apparatus includes a developing roller, a developing agent, a refilling port, a transport member, and an agitation enhancer. The developing agent includes toner particles and carrier particles and is refilled to the developing apparatus from the refilling port. The transport member transports the developing agent to the developing roller while agitating the developing agent. The agitation enhancer is provided on a peripheral portion of the transport member to increase agitation movement of the developing agent.

Developing apparatus having improved agitation effect

A developer for developing an electrostatic latent image, including a carrier which includes core particles, and a surface layer surrounding each of the core particles and containing an acrylic resin binder; and a toner which includes toner particles and an external additive of inorganic or organic fine particles present on each of the toner particles. Each of the toner particles comprises a colorant, a matrix of a first resin, and a plurality of domains of a second resin dispersed in the matrix and containing a wax. The first resin is substantially free of tetrahydrofuran insoluble matters and has a weight average molecular weight of 3,000 to 90,000.

Developer for developing electrostatic latent image and image forming apparatus

A developer container includes a developer container configured to contain a developer including a toner and a carrier, a developer delivering mechanism configured to deliver the developer toward an image bearing member of an image forming apparatus, and a detecting mechanism configured to detect deterioration of the developer based on a predetermined characteristic of the developer.

Method and apparatus for image forming effectively detecting deterioration of developer

A developer container includes a developer storage unit made of a flexible sheet material for storing developer, and a cap unit from which the developer is discharged. The developer storage unit includes a holding member that holds a folded state when the developer storage unit is folded.

Developer container, developer supplying unit, and image forming apparatus

A developing device includes a developer carrier that carries a developer and a developer restricting member that restricts a layer thickness of the developer on the developer carrier. The developer carrier carries the developer in such a manner that a thickness Tup of a layer of the developer when the layer passes through the developer restricting member and a gap Gd between the developer restricting member and the developer carrier satisfy an inequality 7&#x3c;Tup/Gd&#x3c;20.

Developing device, image forming apparatus and process cartridge including the developing device, and developing method

A method of developing a latent image formed on an image carrier with toner, including causing a developer carrier, which faces the image carrier and accommodates a magnet therein, to support a developer having a toner and a magnetic carrier supporting the toner and convey the developer to a developing zone between the developer carrier and the image carrier, and providing an apparent coating ratio M of a surface of the developer carrier coated with the developer. The coating ration M is, in a zone upstream of the developing zone in a direction of rotation of the developer carrier, expressed as M=&#x3b1;A2+&#x3b2; (%), where &#x3b1; denotes a coefficient of the coating ratio, A2 denotes an amount of developer for a unit area, &#x3b2; denotes a value determined by a powder characteristic of the developer for an apparent coating ratio calculated with A2=0, and the coating ratio M is between 90% and 120%.

Developing device and process cartridge for an image forming apparatus

A developing unit includes a developer containing unit that contains developer, a developer carrier that has a moving surface, and carries the developer, a magnetic force generator that attracts the developer onto the moving surface by a magnetic force generated from a plurality of magnets, and a restricting member that restricts a layer thickness of the developer. The magnets includes a restricting magnet arranged closest to the restricting member and has a restricting magnetic pole of which a first surface toward the moving surface and a second surface toward an upstream adjacent magnet that is arranged so as to be adjacent to an upstream side of the developer carrier in a direction of movement of the moving surface and has an upstream adjacent magnetic pole form a ridged corner portion, and the ridged corner portion is chamfered.

Developing unit and image forming apparatus

A developing apparatus which uses a two-component developer consisting of a toner and carrier. The ratio between the amount of the developer Mwhich is drawn onto a developing sleeve and refluxes while being regulated by a doctor blade, and the amount of the developer (drawn amount) Mwhich passes through the doctor blade is M/M&#x3c;10. The toner is a negatively-charged toner. In a charge amount distribution the number of toners of &#x2212;1 fc/10 &#x3bc;m or more is 20% or less of the total number of toners.

Developing apparatus for image forming apparatus

A method of developing a latent image formed on an image carrier with toner, including causing a developer carrier, which faces the image carrier and accommodates a magnet therein, to support a developer having a toner and a magnetic carrier supporting the toner and convey the developer to a developing zone between the developer carrier and the image carrier, and providing an apparent coating ratio M of a surface of the developer carrier coated with the developer. The coating ration M is, in a zone upstream of the developing zone in a direction of rotation of the developer carrier, expressed as M=&#x3b1;A+&#x3b2; (%), where &#x3b1; denotes a coefficient of the coating ratio, Adenotes an amount of developer for a unit area, &#x3b2; denotes a value determined by a powder characteristic of the developer for an apparent coating ratio calculated with A=0, and the coating ratio M is between 90% and 120%.

A color toner which gives a suitable image gloss and has an excellent color reproducibility, which has sufficient anti-offset properties even when a release oil is not coated on a fixing roller or is coated in only a small amount, and which has excellent transfer properties, durability, and charge stability relative to humidity is disclosed. Also, an image-forming apparatus using the color toner and a toner container filled with the color toner are disclosed. The color toner comprises a continuous phase of a resin containing a urea-modified polyester resin; and a modified resin dispersed in the continuous phase, wherein the modified resin contains a release polymer portion containing a release polymer; and a modified portion containing a plurality of vinyl monomer units, the modified portion having an average ester group concentration of 8% by weight to 30% by weight.

Growing community of inventors

Kanagawa, Japan

Takayuki Koike