Ricoh Company, Ltd.

Rocoh Company, Ltd.

Mariko Takii

Hiroshi Hosokawa

Yutaka Takahashi

Koichi Sakata

Toyoaki Tano

Hitoshi Iwatsuki

Hiroyuki Kishida

Saori Yamada

Hisashi Nakajima

Masashi Nagayama

Hiroshi Tohmatsu

Yoshihiro Murasawa

Kimitoshi Yamaguchi

Shigenori Yaguchi

Kenichi Mashiko

Haruki Murata

Minoru Masuda

Toyoshi Sawada

Yoshitaka Sekiguchi

Tohru Suganuma

Shinya Hanatani

Masato Taikoji

Kei Niwayama

Shinya Nakagawa

Masahiro Seki

Kohsuke Miyazaki

Toshio Koike

Kenji Kikuchi

Shinji Tamaki

Mitsuo Aoki

Shunji Katoh

Hiroshi Ikeguchi

Michiharu Suzuki

Keinosuke Kondoh

Takahiro Nakamura

A carrier for developing an electrostatic latent image includes a core material particle and a resin layer covering a surface of the core material particle. The resin layer includes a resin and at least one kind of a fine particle. At least one kind of the fine particles includes a chargeable fine particle. The chargeable fine particle has a long diameter of 400 to 900 nm. The chargeable fine particle has a shape factor SF-1 of 160 to 250.

Carrier for developing electrostatic latent image, two-component developer, developer for replenishment, image forming device, process cartridge, and image forming method

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 developing device, including: a developer containing toner and carrier; and developer bearer configured to have surface thereof bear the developer and endlessly move, and to develop latent image over surface of latent image bearer by supplying toner in developer to latent image in developing region facing the latent image bearer, wherein carrier contains fine particles, value X in volume resistivity R (=10) (&#x3a9;&#xb7;cm) of carrier is 11.5-16.0, developer bearer includes: magnetic field generating unit including a plurality of magnetic poles; and developing sleeve having a cylindrical shape enclosing magnetic field generating unit, and configured to bear developer over outer circumferential surface of cylindrical shape by magnetic force of the magnetic field generating unit and perform surface moving by rotating relative to developing device body, and developing device includes developing sleeve voltage applying unit configured to apply AC component-containing voltage to developing sleeve.

Developing device and image forming apparatus

Provided is an electrostatic latent image developing white toner, including: a white toner including at least a binder resin, a white pigment, and a release agent; and a magnetic carrier including at least a core material, and a coating layer coating the core material and made of a coating resin and conductive particles, wherein Ra of the magnetic carrier is in a range of from 0.50 &#x3bc;m to 1.00 &#x3bc;m, and a bulk density of the magnetic carrier is in a range of from 2.08 g/cmto 2.24 g/cm.

Electrostatic latent image developing white developer, image forming method, image forming apparatus, and process cartridge

A carrier includes a core and a covering layer covering the core and including at least carbon black and a filler. The maximum height Ry of the surface of the carrier is from 4.0 &#x3bc;m to 5.0 &#x3bc;m.

Carrier, two-component developer, developer for replenishment, process cartridge, image forming apparatus, and image forming method

A carrier includes a resin layer including Al and Sn and covering the surface of the carrier. A detectable amount of Al is from 1.0% to 12.1% by atom and a ratio (Al/Sn) of the detectable amount of Al to that of Sn is from 2.0 to 50.0 when the carrier is subjected to an X-ray photoelectron spectroscopic (XPS) analysis.

Carrier and developer

Carrier for image forming includes a core material particle including a magnetic material and a coating layer disposed on the surface of the core material particle, the coating layer including a resin, carbon black, an inorganic particulate A, and an inorganic particulate B. The carbon black has a concentration gradient along a thickness direction of the coating layer with a concentration from high to low toward a surface of the coating layer while the inorganic particulate A has a concentration gradient along a thickness direction of the coating layer with a concentration from low to high toward the surface of the coating layer. The volume ratio of the carbon black is 0-30 percent at a depth range of 0.0-0.1 &#x3bc;m from the surface of the coating layer. The inorganic particulate A is electroconductive with a powder specific resistance of 200 &#x3a9;&#xb7;cm or less.

Carrier, developing agent, image forming apparatus, image forming method, replenishment toner, and process cartridge

A carrier for developing electrostatic latent images is provided. The carrier includes a magnetic core particle and a resin layer coating a surface of the magnetic core particle. The resin layer includes a particulate material A having a volume average particle diameter (a) and a particulate material B having a volume average particle diameter (b). The volume average particle diameter (a) of the particulate material A is the largest among volume average particle diameters of all particulate materials included in the resin layer, and an inequation 100&#x2265;(a)/(b)&#x2265;5 is satisfied. The particulate material A is barium sulfate.

Carrier for developing electrostatic latent images, two-component developer, image forming apparatus, toner storing unit, and supplemental developer

A toner housing container includes a container body housing a toner; a conveying portion conveying the toner from one end of the container body, in a longer direction of the container body, to its other end at which a container opening portion is provided; a pipe receiving port receiving a conveying pipe fixed to a toner conveying device; and an uplifting portion moving the toner toward a toner receiving port of conveying pipe. Such toner has a molecular weight distribution having a peak in a range of 10to 10, and has C/R of from 0.03 to 0.55 between peak height C attributed to crystalline polyester resin and R attributed to non-crystalline resin when measured by FT-IR after stored at 45&#xb0; C. for 12 hours.

Toner housing container and image forming apparatus

A carrier for developing an electrostatic latent image of the present invention includes a core material and a coating layer which coats the core material, wherein the coating layer includes a resin and fine particles, wherein the coating layer has an average layer thickness difference of 0.02 &#x3bc;m to 3.0 &#x3bc;m, and wherein the carrier for developing an electrostatic latent image has an arithmetic mean surface roughness Ra1 of 0.5 &#x3bc;m to 0.9 &#x3bc;m.

Carrier for developing an electrostatic latent image, developer and image forming apparatus

A toner, including: a binder resin; and a colorant, wherein the binder resin contains: a crystalline polyester resin (A); a non-crystalline resin (B); and a composite resin (C), where the composite resin (C) contains a condensation polymerization resin unit and an addition polymerization resin unit, wherein the toner contains chloroform insoluble matter in an amount of 1% by mass to 30% by mass, wherein the toner has a molecular weight distribution having a main peak in a range of 1,000 to 10,000 and a half width of 15,000 or less, where the molecular weight distribution is obtained through gel permeation chromatography (GPC) of tetrahydrofuran soluble matter of the toner, and wherein the toner has an endothermic peak in a range of 90&#xb0; C. to 130&#xb0; C. in measurement through differential scanning calorimetry (DSC).

Toner, image forming apparatus, image forming method, and process cartridge

A toner for forming an electrophotographic image is provided, wherein the toner includes at least four types of binder resins,

Toner for forming electrophotographic image, method for manufacturing toner for forming electrophotographic image, image forming method, and process cartridge

A toner including a crystalline polyester resin (A), an amorphous resin (B), and a composite resin (C) having a condensation polymerization resin unit and an addition polymerization resin unit is provided. A molecular weight distribution of the toner based on THF-soluble contents thereof has a main peak within a molecular weight range from 1,000 to 10,000 and a half bandwidth of the main peak is 15,000 or less. The molecular weight distribution is determined by gel permeation chromatography. The toner includes chloroform-insoluble contents. A ratio C/R of the toner is within a range from 0.03 to 0.55. C and R represent heights of spectrum peaks specific to the crystalline polyester resin (A) and the amorphous resin (B), respectively, determined by a Fourier transform infrared spectroscopic attenuation total reflection method after the toner is stored in a thermostatic chamber at 45&#xb0; C. for 12 hours.

Toner, image forming method, and process cartridge

To provide an image forming method, containing: a charging step, a latent electrostatic image forming step, a developing step, a transferring step, and a fixing step, wherein the developing step is developing the latent electrostatic image formed on the latent electrostatic image bearing member with a two-component developer containing a toner and a carrier by a developing element to form a visible image, where the developing contains: stirring the toner and the carrier to prepare the two-component developer to have a flow energy amount of 30 mJ to 70 mJ; and periodically discharging and transporting the stirred two-component to the developer unit by air pressure to thereby supply the two-component developer for the developing.

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Kanagawa, Japan

Mariko Takii