Fuji Xerox Co., Ltd.

Masaaki Usami

Takeshi Tanabe

Takeshi Iwanaga

Yosuke Tsurumi

Yuka Zenitani

Toshiaki Hasegawa

Sakon Takahashi

Yasunobu Kashima

Hiroshi Kamada

Moegi Iguchi

Yasuaki Hashimoto

Takuro Watanabe

Motoko Sakai

Hiroaki Saijo

Yuta Saeki

Yasuo Matsumura

Shuji Sato

Masahiro Takagi

Takashi Tanabe

An electrostatic charge image developing toner includes toner particles, silica particles having an average particle diameter of 80 nm to 200 nm, lubricant particles N which has negatively chargeable property, and lubricant particles P which has positively chargeable property, wherein a content (s) of the silica particles, a content (n) of the lubricant particles N, and a content (p) of the lubricant particles P satisfy relationships of Expression (1): 0.002&#x2264;p/s&#x2264;0.2; and Expression (2): 0.02&#x2264;n/s&#x2264;0.5.

Electrostatic charge image developing toner, electrostatic charge image developer, and toner cartridge

An electrostatic charge image developing toner includes: toner particles; first silica particles having an average circularity of 0.9 to 1.0, a particle size distribution index of 1.05 to 1.25, and a compression aggregation degree of 60% to 95%; and second silica particles having an average circularity of 0.9 to 1.0, a particle size distribution index of 1.05 to 1.25, and a compression aggregation degree of 60% to 95%, wherein, when an average primary particle diameter of the first silica particles is set as Da (nm) and an average primary particle diameter of the second silica particles is set as Db (nm), relationships of the following Expressions (A1) to (A3) are satisfied: Expression (A1): 80&#x2266;Da&#x2266;120, Expression (A2): 120&#x2266;Db&#x2266;200, and Expression (A3): 10&#x2266;Db&#x2212;Da&#x2266;120.

A carrier for two-component developer includes a magnetic particle and a resin coating layer that covers the magnetic particle and contains a resin, wherein a weight average molecular weight of the resin contained in the resin coating layer is from 1,800,000 to 5,000,000.

Carrier for two-component developer, two-component developer, and method of preparing carrier for two-component developer

An electrostatic charge image developing carrier includes magnetic particles and a resin coating layer which covers the magnetic particles, wherein a sulfate ion concentration of the resin coating layer is 0.05% by weight or less with respect to a total weight of the resin coating layer, and when a total value of a molar amount of sulfate ions contained and a molar amount of sulfo groups contained per 1 g of the resin coating layer is A mol and a molar amount of sodium ions contained per 1 g of the resin coating layer is B mol, a relationship of 0.1&#x3c;B/A&#x3c;1.2 is satisfied.

Electrostatic charge image developing carrier, method of preparing electrostatic charge image developing carrier, and electrostatic charge image developer

An electrostatic charge image developer includes an electrostatic charge image developing carrier containing a ferrite particle and an electrostatic charge image developing toner containing metallic particles whose resistance is from 10&#x3a9;cm to 10&#x3a9;cm in an electric field of 10,000 V/cm, wherein the electrostatic charge image developing carrier satisfies the following formula (1): 0.9&#x2266;R/R&#x2266;1.0 (1), wherein Rrepresents the resistance of the electrostatic charge image developing carrier in an electric field of 2,400 V/cm, and Rrepresents the resistance of the electrostatic charge image developing carrier in an electric field of 19,200 V/cm.

Electrostatic charge image developer, developer cartridge, and process cartridge

An electrostatic charge image developing toner includes a toner particles containing a binder resin and a metallic pigment and aliphatic acid metal salt particles as an external additive in an amount of from 0.1 parts by weight to 2.0 parts by weight with respect to 100 parts by weight of the toner particles, wherein the toner particles have an average circle equivalent diameter D longer than an average C of a maximum thickness of the toner particles.

A developer for electrophotography which is excellent in the retention of the charge quantity of the toner and the controllability of the charge quantity, scarcely causes adhesion of the carrier to image areas and can provide stable image quality is disclosed, the developer comprising a toner containing a quaternary ammonium salt type charge control agent dispersed in a binder resin and a carrier coated with a resin comprising, as essential components, a vinylidene fluoride monomer unit-containing resin and a methylphenylsilicone resin.

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Kanagawa, Japan

Masaaki Usami