Ricoh Company, Ltd.

Shizuoka University

Shinichiro Yagi

Toshiki Nanya

Shigeru Emoto

Masami Tomita

Hiroto Higuchi

Fumihiro Sasaki

Naohiro Watanabe

Junichi Awamura

Tomoyuki Ichikawa

Hiroshi Yamashita

Yoshiki Yamaguchi

Hiroshi Yamada

Kousuke Suzuki

Tsunemi Sugiyama

Hitoshi Iwatsuki

Osamu Uchinokura

Satoshi Mochizuki

Hiroaki Matsuda

Tatsuya Niimi

Masanori Suzuki

Yasuaki Iwamoto

Koichi Sakata

Yohichiroh Watanabe

Shinya Nakayama

Jun Okamoto

Hisashi Nakajima

Hiroshi Nakai

Naohito Shimota

Maiko Kondo

Takahiro Honda

Tadao Takigawa

Tomio Kondou

Tomomi Suzuki

Masashi Nagayama

Hiroyuki Fushimi

Takuya Saito

Akinori Saitoh

Tadao Takikawa

Kohki Katoh

Yuuki Mizutani

Tomomi Tamura

Masato Taikoji

Hideki Sugiura

Akihiro Kotsugai

Yasuo Asahina

Masayuki Ishii

Shinji Ohtani

Tomoko Utsumi

Tomio Kondoh

Takayuki Shimizu

Mitsuo Aoki

Akira Sawada

Kumi Hasegawa

Masanori Rimoto

Takeshi Sako

Kohsuke Suzuki

Kazumi Ohtaki

Akemi Sugiyama

Kazuyuki Yazaki

Idzumi Okajima

Kanjiroh Kawasaki

Masahide Yamada

Hltoahi Iwatsuki

Naohito Bell Shine Takehara A-103 Shimota

Tomoyuki Dai6 Sumika Bldg 206 Ichikawa

Naohito Shimoda

A method of preparing a developer includes mixing a carrier and a powder with each other while falling with gravity.

Method of preparing developer, developer for electrophotography, process cartridge and image forming apparatus

A method for regenerating a carrier core material for electrophotography, including: treating a carrier for electrophotography including a carrier core material for electrophotography and a coating layer on a surface of the carrier core material for electrophotography with an aqueous solution including an oxidant in a subcritical state or a supercritical state having a temperature of 280&#xb0; C. or greater and a density of 0.20 g/cmor greater, wherein an amount of the oxidant in a total amount of the aqueous solution used in the treating is greater than 0.05 parts by mass with respect to 1 part by mass of the carrier for electrophotography to be treated in the treating.

Method for regenerating carrier core material for electrophotography, method for manufacturing carrier for electrophotography, and carrier for electrophotography

A method of preparing a carrier for electrophotography, including a core material and a coating material layer formed on the surface of the core material, including:

Method of preparing carrier for electrophotography

A method of manufacturing a carrier including covering a core material with a covering material to form a covering layer on the core material and baking the covering material by heating the core material by high frequency induction applied thereto by a high frequency induction heating device.

Method of manufacturing a carrier, a carrier, a development agent, and a process cartridge

A method of preparing carrier for electrophotography, which includes a core material and a coating material layer formed on the surface of the core material, including coating a coating material of the coating material layer on the core material; and burning the coating material by an induction heater, wherein the induction heater applies an alternative current to parallely-located plural coil circuits including a conductive wire including the shape of a coil to generate a magnetic line changing its direction and intensity for inductively heating the core material to heat the coating material.

Method of preparing carrier for electrophotography, carrier for electrophotography, developer for electrophotography, process cartridge and image forming apparatus

The present invention relates to toner compositions containing: toner particles made of: binder resin; colorant; and a wax which is dispersed in the toner particles, where the toner composition satisfies relationship (2): B&#x2266;394&#x2212;400A' when 0.950&#x3c;A&#x2032;&#x2266;0.965 (2) where A&#x2032; represents an average circularity of the toner composition, B represents a content of toner particles having a particle diameter not greater than 3 &#x3bc;m expressed in % by number, and a concentration of the wax at a surface of the toner particles is larger than a concentration thereof in the center of the toner particles.

Toner, developer and image forming apparatus

To provide an electrophotographic developer carrier including a carrier core material, and a coat layer containing a binder resin and conductivity-imparted microparticles which are produced by imparting conductivity to inorganic microparticles, the coat layer being formed over the carrier core material, wherein the electrophotographic developer carrier has a static resistivity of 10 [Log (&#x3a9;&#xb7;cm)] or higher and a dynamic resistivity of 9 [Log (&#x3a9;)] or lower, and is used in an electrophotographic developer together with a negatively chargeable toner having an average circularity of 0.925 to 0.970, and wherein the toner includes a resin, a colorant and an inorganic layered mineral in which at least part of interlayer ions is modified with organic ions, and is granulated by dispersing and/or emulsifying an oil phase and/or a monomer phase containing at least a toner composition and/or a toner composition precursor in an aqueous medium.

Electrophotographic developer carrier, electrophotographic developer, image forming method, process cartridge and image forming apparatus

An image forming apparatus including at least an image bearer; a charger charging the image bearer; an irradiator irradiating the image bearer to form an electrostatic latent image thereon; an image developer developing the electrostatic latent image with a developer comprising a toner and a carrier to form a toner image on the image bearer; a developer feeder feeding a supplemental developer including the toner and the carrier into the image developer; and a developer collector collecting the developer in the image developer, wherein the developer feeder includes a cylindrical supplemental developer container containing the supplemental developer, including a spiral developer guide race on the inner circumferential surface thereof; and a sub-hopper configured to store the supplemental developer, and wherein the carrier includes a core material; and a layer coated on the core material, including a binder resin and non-black or a non-color inorganic particulate material.

Image forming apparatus, process cartridge, image forming method and developer for electrophotography

An image forming apparatus including an image bearing member; and a developing device including a developer bearing member, a developer containing portion, a developer supplying passage supplying the developer to the developer bearing member while feeding the developer in a direction, and a developer agitating passage feeding a mixture of the developer fed through the developer supplying passage without used for developing, and the developer used for developing, in the opposite direction. The developer supplying passage, and developer agitating passage are separated from each other except for at least both the end portions. The developer includes a toner and a carrier having a cover layer thereon, which includes a binder resin and a particulate material. The ratio of the volume average particle diameter of the particulate material to the average thickness of the resinous portion of the cover layer is greater than 1 and less than 10.

Image forming apparatus for use with carrier including a core and cover layer

A carrier for use in an image forming apparatus in which a toner and a carrier are fed to an image developer thereof and an extra developer including the toner and the carrier in the image developer is discharged therefrom, wherein at least one of the carrier fed to the image developer and a carrier readily contained therein includes a core material; and a coated film coating the core material, and wherein the coated film includes a binder resin and a particulate material having a ratio of an average particle diameter thereof to an average thickness of the coated film of from 0.01 to 1, and includes concavities and convexities having an average difference of elevation of from 0.02 to 3.0 &#x3bc;m.

Carrier, supplemental developer, developer in image developer, developer feeding apparatus, image forming apparatus and process cartridge

Provided is a developing device containing a two-component developer including a magnetic carrier and a toner; a developer bearing member containing a nonmagnetic developing sleeve configured to bear the two-component developer on a surface thereof while rotating; a magnetic field generating unit fixed inside of the nonmagnetic developing sleeve; and a developer amount control member configured to control an amount of the two-component developer borne on the developer bearing member. The magnetic carrier contains a core material and a coating layer coated on the core material, and the coating layer containing a binder resin and conductive particles. The magnetic carrier satisfy a ratio D/h of 1.00&#x3c;[D/h]&#x2266;1.95, where D denotes an average primary particle diameter of the conductive fine particles, and h denotes a thickness of the coating layer, and a ratio Ra/D of 1.0&#x3c;[Ra/D]&#x3c;10.0, where Ra denotes a surface roughness of the developing sleeve.

Developing device, image forming apparatus, and process cartridge

A toner composition including toner particles including at least a binder resin; and a colorant, wherein the toner composition satisfies at least one of the following relationships (1) and (2):B&#x2266;14 when 155&#x3c;A&#x2266;180; and&#x2266;0.6&#x2212;79 when 145&#x2266;&#x2266;155,&#x2003;&#x2003;(1)wherein A represents a shape factor SF-1 of the toner composition and B represents a content of toner particles having a particle diameter not greater than 3 &#x3bc;m; andB&#x2266;14 when 0.920&#x2266;A'&#x2266;0.950; and&#x2266;394&#x2212;400&#x2032; when 0.950&#x3c;&#x2032;&#x2266;0.965&#x2003;&#x2003;(2)wherein A&#x2032; represents an average circularity of the toner composition and B represents a content of toner particles having a particle diameter not greater than 3 &#x3bc;m.

An image forming apparatus including an image bearing member; a charger; a light irradiator; a developing device; a transfer device; an image bearing member's cleaner; and a fixing device, wherein the fixing device includes a fixing member configured to fix a toner image upon application of heat and pressure thereto; a pressing member configured to press the recording material toward the fixing member; and a cleaning member configured to clean a surface of the fixing member and/or the pressing member, wherein the cleaning member has an outermost layer including a reactive material which increases viscoelasticity of a binder resin of the toner by reacting with the binder resin.

Fixing device, and image forming apparatus using the fixing device

The object of the present invention is to provide a carrier for electrophotography which includes a core material and a coating layer comprising particles on a surface of the core material, in which the carrier for electrophotography comprises indium (In) in an amount of 0.0001% by mass to 0.5% by mass. The present invention also provides a developer using the carrier, a developer container, an image forming method, an image forming apparatus, and a process cartridge in each of which the carrier is used.

Indium-containing carrier for electrophotography, developer using the same, and developer container

A toner composition including toner particles including a binder resin including a modified polyester resin, and a second resin having a weight average molecular weight of from 2,000 to 10,000; a colorant; a release agent; and a particulate material which is present at least a surface portion of the toner particles while embedded into the surface portion, wherein the binder resin has a glass transition temperature not lower than 35&#xb0; C. and lower than 55&#xb0; C., and wherein the particulate material has an average particle diameter of from 0.002 to 0.2 times that of the toner particles. A developer including the toner composition and a carrier having a layer thereon which includes at least an acrylic resin and a silicone resin, and a method for fixing an image of the toner composition are also provided.

Toner, developer including the toner, and method for fixing toner image

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Numazu, Japan

Shinichiro Yagi