Ricoh Company, Ltd.

Masahiro Seki

Masashi Nagayama

Yoshitaka Sekiguchi

Hiroyuki Kishida

Koichi Sakata

Ryota Inoue

Satoshi Ogawa

Kazuoki Fuwa

Shinya Nakagawa

Saori Yamada

Mariko Takii

Tohru Suganuma

Kei Niwayama

Kohsuke Miyazaki

Yoshihiro Mikuriya

Kousuke Suzuki

Shun Saito

Yoshimichi Ishikawa

Takayuki Nakamura

Tomohiro Fukao

Toyoaki Tano

Hiroaki Katoh

Haruki Murata

Namie Suzuki

Naoko Kitada

A carrier can be used for forming an electrophotographic image. The carrier contains a core particle and a coating layer coating the core particle. The coating layer contains a chargeable particle. The carder has an internal void ratio of 0.0% or greater but less than 2.0%, and an apparent density of 2.0 g/cmor greater but less than 2.5 g/cm.

Carrier for forming electrophotographic image, developer for forming electrophotographic image, electrophotographic image forming method, electrophotographic image forming apparatus, and process cartridge

A carrier for forming an electrophotographic image is provided. The carrier includes a core particle comprising a manganese-based ferrite particle having an apparent density of from 2.0 to 2.2 g/cmand a magnetization of from 44 to 52 emu/g in a magnetic field of 500 Oe; and a coating layer coating a surface of the core particle. The coating layer contains a carbon black, an inorganic particle A, and an inorganic particle B. The inorganic particle A and the carbon black each have a concentration gradient in a thickness direction of the coating layer. A concentration of the inorganic particle A increases toward a surface of the coating layer, and a concentration of the carbon black decreases toward the surface of the coating layer.

Carrier, developer, method, and apparatus for forming electrophotographic image, and process cartridge

Provided is a carrier for a developer of an electrostatic latent image, the carrier including a core particle, and a resin layer covering the core particle, where the resin layer includes metal compound particles, wherein the metal compound particles include magnesium compound particles or barium compound particles, and an exposed amount B (atomic %) of the magnesium or the barium on a surface of the carrier particle satisfies a relationship below:10.0&#x2265;B &#x2265;1.2.

Carrier for developer of electrostatic latent image, two-component developer, replenishing developer, image forming apparatus, and toner stored unit

A carrier is provided including a core particle and a resin layer coating the surface of the core particle. The resin layer includes fine metal particles, and a detected metal element amount A obtained by X-ray photoelectron spectrometry of the surface of the carrier is in a range of 4.0 atomic %&#x2264;A&#x2264;20.0 atomic % and an average major-axis length B of the fine metal particle exposing from the resin layer is in a range of 100 nm&#x2264;B&#x2264;800 nm.

Carrier, developer, supplemental developer, image forming apparatus, image forming method, and process cartridge

A carrier for a developer of an electrostatic latent image, the carrier including: core particles having magnetism; and a coating layer coating a surface of each of the core particles, wherein the coating layer includes two or more kinds of inorganic particles, at least one kind of inorganic particles among the two or more kinds of inorganic particles is inorganic particles A having conductivity and a peak particle diameter of from 300 nm through 1,000 nm, and surface roughness of the carrier calculated by Formula 1 below is from 1.10 m/g through 1.90 m/g,C&#x2212;F&#x2003;&#x2003;Formula 1where C is a BET specific surface area (m/g) of the carrier and F is a BET specific surface area (m/g) of the core particles.

Carrier for developer of electrostatic latent image, developer, and image forming apparatus

A toner including a binder resin, wherein the toner includes a tetrahydrofuran (THF)-insoluble component in a range of from 10% by mass through 40% by mass, wherein the toner has a main peak in a range of from 12,000 through 18,000 in a molecular weight distribution of a THF-soluble component as measured by gel permeation chromatography (GPC), wherein the main peak has a half value width in a range of from 20,000 to 50,000, and wherein the toner includes a component having a molecular weight of 2,000 or less in a range of from 10.0% by mass through 20.0% by mass and a component having a molecular weight of 100,000 or more of 8.0% by mass or less.

Toner, toner stored unit, and image forming apparatus

A toner, including: a binder resin; releasing agent-encapsulating capsules; and a colorant, wherein the releasing agent-encapsulating capsules each include: a capsule formed of a resin (I) which is different from the binder resin; and a releasing agent (RA) which is encapsulated in the capsule, and the releasing agent-encapsulating capsules exist in the binder resin, and wherein 50% to 100% of the releasing agent-encapsulating capsules exist in a region from a surface of the toner to a depth of 0.10 times a volume-average particle diameter of the toner.

Toner, developer, process cartridge, and image forming apparatus

A toner including: a base resin; and charge-controlling resin particles contained in the base resin, wherein the toner is in shape of particles, and the charge-controlling resin particles are present in a region of each toner particle which is 500 nm in depth from a surface of the toner particle and an average of amounts of the charge-controlling resin particles present in the regions of the toner particles is 20% by volume to 70% by volume, wherein an average of embedment rates of the charge-controlling resin particles in the toner particles is 90% or higher, where each embedment rate is an average of embedment rates of the charge-controlling resin particles in each toner particle, and wherein the charge-controlling resin particles have a charge amount of 60 &#x3bc;C/mor more as measured by a blow-off method.

Toner, method for producing the same, and image forming apparatus

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Shizuoka, Japan

Masahiro Seki