Ricoh Company, Ltd.

Namie Suzuki

Yoshitaka Yamauchi

Kazumi Suzuki

Hisashi Nakajima

Kousuke Suzuki

Masashi Nagayama

Hiroyuki Kishida

Akihiro Kaneko

Kohtaroh Ogino

Minoru Masuda

Tohru Suganuma

Masahiro Seki

Kento Takeuchi

Kaede Masuko

Teruyuki Suzuki

A carrier for forming an electrophotographic image is provided. The carrier comprises a core particle and a coating layer coating the core particle. The coating layer contains a conductive component comprising an element A, and a coating resin comprising an element B. The element A is undetected in the coating resin by an energy dispersive X-ray spectrometer, and the element B is undetected in the conductive component by the energy dispersive X-ray spectrometer. A standard deviation of a value A/B is 0.4 or less, where the value A/B is a ratio of the element A to the element B in intensity measured by the energy dispersive X-ray spectrometer.

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

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

Provided is a toner including toner particles, each toner particle includes: a base particle including a binder resin; and external additive particles, wherein the external additive particles include particles each having an equivalent circle diameter of 10 nm or greater, a volume average particle diameter of the particles each having an equivalent circle diameter of 10 nm or greater is 80 nm or greater but 140 nm or less, and a ratio (circumscribed circle area/particle area) of a circumscribed circle area of the particle having an equivalent circle diameter of 10 nm or greater to a particle area of the particle having an equivalent circle diameter of 10 nm or greater is 1.60 or greater but 2.60 or less.

Toner, toner stored unit, and image forming apparatus

A toner is provided. The toner comprises a binder resin, a release agent, and a function imparting agent comprising a fatty acid amide having a melting point of from 110 to 160 degrees C. When the toner is heated by a differential scanning calorimeter, the toner exhibits no endothermic peak within a temperature range of &#xb1;20 degrees C. of a temperature at a highest endothermic peak derived from the fatty acid amide.

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

A toner is provided. The toner comprises mother particles and an external additive covering the mother particles. The mother particles comprise a binder resin, and the external additive comprises inorganic particles. The inorganic particles comprise small-size inorganic particles having an equivalent circle diameter of from 30 to 70 nm and large-size inorganic particles having an equivalent circle diameter of from 150 to 200 nm and a circularity of 0.85 or more. The large-size inorganic particles are 20 to 70 in number per 100 &#x3bc;mimage area of the toner observed with a field-emission scanning electron microscope.

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

A toner is provided. The toner comprises a binder resin comprising a polyester resin, a release agent comprising an ester wax, and a wax dispersing agent comprising a hybrid resin. The hybrid resin comprises a condensation polymerization resin unit and an addition polymerization resin unit. The condensation polymerization resin unit comprises a condensation polymerization product of an aromatic alcohol component and a carboxylic acid component, and the carboxylic acid component comprises an aliphatic dicarboxylic acid having 9 to 14 carbon atoms. The addition polymerization resin unit comprises an addition polymerization product of a styrene monomer.

Toner and image forming method

A toner for electrophotography, the toner including an amorphous polyester resin, an addition polymerization-based resin, and wax that is ester wax or carnauba wax, wherein the toner satisfies relationships represented by Formula 1 and Formula 2 below,&#x2003;&#x2003;(Formula 1)|&#x2003;&#x2003;(Formula 2)where SPr is a value of a solubility parameter of the amorphous polyester resin, SPw is a value of a solubility parameter of the wax, and SPd is a value of a solubility parameter of the addition polymerization-based resin.

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Shizuoka, Japan

Namie Suzuki