Ricoh Company, Ltd.

Mitsui Petrochemical Industries, Ltd.

Tomomi Suzuki

Junichi Awamura

Yasuo Asahina

Masami Tomita

Hiroshi Yamada

Toshiki Nanya

Shigeru Emoto

Satoshi Mochizuki

Hiroto Higuchi

Fumihiro Sasaki

Osamu Uchinokura

Masahide Yamada

Shinichiro Yagi

Minoru Masuda

Hideki Sugiura

Toyoshi Sawada

Takuya Seshita

Satoshi Kojima

Yasuaki Iwamoto

Masashi Nagayama

Tomoyuki Ichikawa

Yoshiki Yamaguchi

Shinya Nakayama

Tsuyoshi Sugimoto

Naohiro Watanabe

Koichi Sakata

Ryota Inoue

Akihiro Kotsugai

Jun Okamoto

Kazuhiko Umemura

Tsunemi Sugiyama

Hisashi Nakajima

Shinichi Kuramoto

Masayuki Ishii

Hiroyuki Kishida

Hiroshi Yamashita

Hiroaki Matsuda

Daisuke Ito

Daisuke Inoue

Naohito Shimota

Akinori Saitoh

Takahiro Honda

Teruki Kusahara

Tohru Suganuma

Kohtaroh Ogino

Kento Takeuchi

Tohru Moriya

Hiroyuki Fushimi

Tsuneyasu Nagatomo

Masahiro Ohki

Shinji Ohtani

Kohki Katoh

Satoru Miyamoto

Shinichi Wakamatsu

Tomoko Utsumi

Hiroshi Yaguchi

Kohsuke Suzuki

Kaede Masuko

Yoshihisa Okamoto

Hidefumi Gohhara

Kazuyuki Hirai

Chiharu Mochizuki

Michio Izumi

Toshihiko Karato

Kazushige Yasumatsu

Kousuke Suzuki

Kazuki Yogosawa

Satoshi Ogawa

Hyo Shu

Takuya Suganuma

Hideo Nakamura

Natsuko Matsushita

Ryuuta Yoshida

Tatsuya Dan

Syouko Satoh

Koshi Sato

Masaru Wakisaka

Naohito Bell Shine Takehara A-103 Shimota

Tomoyuki Dai6 Sumika Bldg 206 Ichikawa

Kazushige Sanyo Chemical Ind Ltd Yasumatsu

Kazuyuki Sanyo Chemical Industries Ltd Hirai

A carrier is provided that includes a core particle and a coating layer coating the core particle. The coating layer includes a resin and chargeable inorganic fine particles, and has voids. The resin has an average film thickness of 0.10 μm or larger and smaller than 0.45 μm. The coating layer has a porosity of 0.1% or higher and lower than 2.8%, when the porosity expressed by the following equation:Porosity [%]=1/2×100where, on a cross section of the coating layer, S1 represents a cross sectional area of the voids and S2 represents a cross sectional area of the resin.

Carrier, developer, image forming method, and process cartridge

A carrier for forming an electrophotographic image contains a core particle and a coating layer coating the core particle, wherein the coating layer contains a particle containing antimony and an anionic dispersant and the particle containing antimony includes a substrate particle containing a first inorganic fine particle.

Carrier for forming electrophotographic image, developing agent for forming electrophotographic image, method of forming electrophotographic image, electrophotographic image forming apparatus, and process cartridge

A developing apparatus includes an electrostatic latent image bearer, a developing sleeve, a case, and an air filter. The case accommodates a two-component developer and the developing sleeve. The air filter is attached to the case. The air filter has a thickness of 2 to 20 mm and has a density gradient with a pressure loss of 2 to 40 Pa at a wind speed of 10 cm/s. The air filter forms an airflow sucked into the case from a gap between the developing sleeve and the case and forms an airflow discharged from the case through the air filter. The two-component developer accommodated in the case contains a magnetic particle a surface of which is coated with a resin layer. The resin layer contains at least one type of chargeable particle.

Developing apparatus, developer for electrophotographic image formation, electrophotographic image forming method, and electrophotographic image forming apparatus

Provided is a toner including at least a binder resin, and having peak ratio W/R of from 0.20 to 0.70 when measured with FT-IR according to ATR method, W/R being a ratio of height W of maximum spectral peak attributed to bisphenol A skeleton of the toner and observed at from 1,480 cmto 1,520 cmto height R of maximum spectral peak attributed to carbonyl group of the toner and observed at from 1,700 cmto 1,750 cm, wherein molecular weight distribution of the toner obtained by GPC of THF-soluble component of the toner has main peak in a range of from 1,000 to 10,000, half value width of the molecular weight distribution is a molecular weight of 20,000 or less, and content of a THF-insoluble component in the toner is from 5% by mass to 40% by mass.

Toner, image forming apparatus, image forming method, and toner stored unit

A toner, containing: a binder resin; and kaolinite, wherein the toner has a molecular weight distribution having a main peak in a range of 1,000 to 10,000, and a half value width of the main peak is 8,000 to 30,000, where the molecular weight distribution is obtained by gel permeation chromatography (GPC) of THF soluble matter of the toner, and wherein the toner contains the kaolinite in an amount of 5% by mass to 35% by mass.

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

A toner, including: a binder resin; and calcium carbonate, wherein the toner has a molecular weight distribution having a main peak in a range of 1,000 to 10,000, and a half value width of the main peak is 8,000 to 30,000, where the molecular weight distribution is obtained by GPC (gel permeation chromatography) of THF soluble matter of the toner, and wherein the toner contains the calcium carbonate in an amount of 5% by mass to 35% by mass.

An image forming toner, including a mother particle including a paraffin wax having a melting point of from 60 to 90&#xb0; C. and a binder resin, wherein the mother particle has an endothermic peak of the paraffin wax of from 2.0 J/g to 5.5 J/g when measured by a DSC and an aspect ratio of from 0.8 to 0.90.

Image forming toner, and developer and process cartridge using the toner

To provide a toner, which contains a binder resin, a colorant, and a releasing agent, wherein the binder resin contains a low molecular weight resin component, where the low molecular weight resin component has a resin softening coefficient (A), represented by the following formula (1), satisfying A&#x3e;0.165, and has storage elastic modulus (dyne/cm) G'(Tfb) satisfying G&#x2032;(Tfb)&#x2266;1&#xd7;10where Tfb is a flow onset temperature (&#xb0; C.) of the low molecular weight resin component as measured by a capillary rheometer:=|[(1)&#x2212;ln&#x2032;(2)]/(1&#x2212;2)|&#x2003;&#x2003;Formula (1)(where T1 is temperature (&#xb0; C.) at which storage elastic modulus G&#x2032;(r1) is 1&#xd7;10(dyne/cm) and T2 is temperature (&#xb0; C.) at which storage elastic modulus G&#x2032;(r2) is 1&#xd7;10(dyne/cm) as measured by means of a viscoelasticity measuring device with measuring frequency of 1 Hz, and measuring distortion of 1 deg; and | | represents an absolute value.).

Toner for electrostatic charge development

The present invention provides a method for producing a toner, the method including: preparing a wax dispersion liquid by cooling a wax solution, in which a wax is heated and dissolved or dispersed in an organic solvent, in a container so that a standard deviation &#x3c3; of a temperature distribution between a center portion of the container and an inner wall of the container is 0.5 or less and the cooling rate is 2.0&#xb0; C./min or more, to precipitate wax particles in the wax solution; forming toner base precursor particles by adding an aqueous phase containing resin fine particles into an oil phase containing at least the wax dispersion liquid, a colorant and a binder resin and mixing the oil phase and the aqueous phase with each other; and preparing toner base particles by removing the solvent from the toner base precursor particles.

Toner, and production method of the same

A method of manufacturing a toner including forming a wax liquid dispersion in which a wax is dispersed in an organic solvent (A1), mixing an organic layer including the wax liquid dispersion, a binder resin and an organic solvent (A) to form an oil phase and dispersing and emulsifying the oil phase in an aqueous medium to obtain an emulsified liquid dispersion, wherein the aspect ratio average of the wax in the wax liquid dispersion is from 0.3 to 0.7 and the toner includes toner particles satisfying the following relationship (1) in an amount of 20% by number or smaller based on all toner particles: 0.5&#x3c;D2/D1, relationship (1), where D1 represents the major diameter (D1) of the toner and D2 represents the major diameter of the wax.

Method of manufacturing toner

A method for producing a toner, containing: dispersing, in an aqueous medium, an oil phase which contains an organic solvent, and a binder resin component contained in the organic solvent, where the binder resin component contains a crystalline polyester resin and an amorphous polyester resin; and removing the organic solvent from the dispersion to obtain the toner, in which the dispersing further contains heating and dissolving the crystalline polyester and the amorphous polyester in the organic solvent to obtain a solution, cooling the solution so as to recrystallize the crystalline polyester resin, and mechanically pulverizing the recrystallized crystalline polyester resin so as to obtain a crystalline polyester dispersion.

Toner, method for producing the same, and developer

A toner including a binder resin, a coloring agent, and a releasing agent, the toner formed by dispersing a toner liquid material which is prepared by dispersing the binder resin, the prepolymer, an elongation agent and/or a cross-linking agent for the prepolymer, the coloring agent, and the releasing agent in an organic solvent, dispersing the toner liquid material in an aqueous medium to obtain a liquid dispersion in at least one of cross linking reaction and elongation reaction, and removing the organic solvent from the liquid dispersion, and the toner satisfying the following relationship: 1.35&#x3c; or =M(g)/M(p)&#x3c; or =1.90, where M(g) represents the content of the gel composition formed in the at least one of cross linking reaction and elongation reaction and M(P) represents the content of the prepolymer in the toner liquid material when the total of M(P) and the content of the binder resin in the toner liquid material is set to be 100 g.

Toner and development agent

A method of manufacturing a toner including dispersing a binder resin, a coloring agent and a releasing agent in an organic solvent to obtain an oil phase; dispersing the oil phase in an aqueous medium with a shearing force to obtain a dispersion emulsion; wherein the shearing force is made by a screen or vessel that is situated around a rotor, the screen spinning in a direction opposite to the direction that the rotor spins. Toner produced. Method of using the toner.

Method of manufacturing toner and toner

A method of manufacturing the toner comprising dispersing at least one of a binder resin or a precursor thereof, a coloring agent and a releasing agent in an organic solvent to obtain an oil phase, dispersing the oil phase in an aqueous medium with a shearing force to obtain a dispersion emulsion, wherein the dispersion emulsion process has plural stages and the shear speed A of the emulsification process of stage n is faster than the shear speed B of the emulsification process of stage n+1.

A toner including a binder resin; a colorant; a release agent; and a modified layered inorganic material in which at least part of interlayer ions is modified with an organic ion, wherein the toner has a volume average particle diameter (Dv) of 3 to 7 &#x3bc;m and a ratio (Dv/Dn) of the volume average particle diameter (Dv) to a number average particle diameter (Dn) of the toner of 1.00 to 1.30, and wherein the release agent is included in the toner in an amount (A) of 1 to 10% by weight, and the ratio (B/A) of the amount (A) to the amount (B) of the release agent included in a classified toner in units of percent by weight is 0.7 to 1.3, wherein the classified toner satisfies the relationship (Dv'/Dn&#x2032;&#x2212;1)/(Dv/Dn&#x2212;1)&#x2266;&#xbe;wherein Dv&#x2032; and Dn&#x2032; respectively represent the volume and number average particle diameters of the classified toner.

Toner for developing electrostatic image, method for preparing the toner, and image forming method and apparatus using the toner

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Numazu, Japan

Tomomi Suzuki