Fujifilm Business Innovation Corp.

Fuji Xerox Co., Ltd.

Sumitomo Electric Industries, Limited

Takuro Watanabe

Yosuke Tsurumi

Shintaro Anno

Yasuo Kadokura

Yasuaki Hashimoto

Kazutsuna Sasaki

Daisuke Noguchi

Karin Sakai

Takashi Inukai

Shuji Sato

Sakon Takahashi

Fusako Kiyono

Satoshi Miura

Osamu Shimakawa

Yoshimasa Fujihara

Moegi Iguchi

Hajime Arao

Motoyoshi Kimura

Dai Sasaki

Motoko Sakai

Sakiko Takeuchi

Hiroaki Saijo

Masaaki Usami

Jumpei Iwasaki

An electrostatic charge image developing carrier, contains: a magnetic particle; and a coating resin layer coating the magnetic particle and containing inorganic particles, in which an area ratio of the inorganic particles that is a ratio of a total area of the inorganic particles to an area of the coating resin layer in a cut surface of the coating resin layer along a thickness direction of the coating resin layer is 10% or more and 50% or less.

Electrostatic charge image developing carrier, electrostatic charge image developer, process cartridge, image forming apparatus and image forming method

An electrostatic charge image developing carrier includes a magnetic particle and a coating resin layer that covers the magnetic particle and contains a silica particle, and a ratio of Si on a surface of the coating resin layer, determined by an X-ray photoelectron spectroscopy (XPS), is 6 atom % or more and 12 atom % or less.

An electrostatic charge image developer containing: a toner containing a toner particle and an external additive; and a carrier containing a magnetic particle and a resin layer covering the magnetic particle, in which the toner particle has a surface property index value of 2.0 or more and 2.8 or less; and the carrier has a surface having a ratio B/A of a surface area B to a planar view area A of 1.020 or more and 1.100 or less, the planar view area A and the surface area B being obtained by three-dimensional analysis of the surface of the carrier.

Electrostatic charge image developer, process cartridge, image forming apparatus, and image forming method

An electrostatic charge image developer contains: a toner containing a toner particle and an external additive; and a carrier containing a magnetic particle and a resin layer covering the magnetic particle; and the toner particle has a surface property index value of 1.0 or more and less than 2.0; and the carrier has a surface having a ratio B/A of a surface area B to a plane view area A of 1.020 or more and 1.100 or less, the plane view area A and the surface area B being obtained by three-dimensional analysis of the surface of the carrier.

An electrostatic charge image developing carrier contains a magnetic particle and a resin coating layer coating the magnetic particle, in which the resin coating layer contains inorganic particles, a ratio B/A of a surface area B of the carrier to a plan view area A of the carrier that are obtained by three-dimensional analysis of a surface of the carrier is 1.020 or more and 1.100 or less, a volume average particle diameter of the magnetic particle is 25 μm or more and 34 μm or less, and a fluidity of the magnetic particle is 28 s/50 g or more and 36 s/50 g or less.

An electrostatic image developer includes a toner including toner particles that include a binder resin and a release agent and have an exposure ratio of the release agent of 15% or more and 30% or less, and a carrier including magnetic particles and resin cover layers covering the magnetic particles and including inorganic particles, wherein the inorganic particles have an arithmetic average particle size of 5 nm or more and 90 nm or less, the resin cover layers have an average thickness of 0.6 μm or more and 1.4 μm or less, and a fine-irregularity-structure surface roughness of surfaces of the carrier three-dimensionally analyzed has, in an analysis region, a ratio B/A of an irregularity-surface area B to a plan-view area A of 1.020 or more and 1.100 or less.

Electrostatic image developer, process cartridge, image forming apparatus, and image forming method

An electrostatic charge image developing carrier includes a magnetic particle and a coating resin layer that covers the magnetic particle, and an amount of the coating resin layer that is peeled off from the magnetic particle when the carrier dispersed in water is irradiated with ultrasonic waves, relative to a coating amount of the coating resin layer before ultrasonic irradiation, is 800 mass ppm or more and 2,000 mass ppm or less, and a difference between an initial coating amount of the coating resin layer of a carrier having no travel history and a coating amount of the coating resin layer of a carrier having a travel history and being taken out from an electrostatic charge image developer, relative to the initial coating amount of the coating resin layer, is 0 mass ppm or more and 3,000 mass ppm or less.

An electrostatic image developing toner includes toner particles, layered compound particles, and inorganic particles. The content of titanium in the electrostatic image developing toner is 0.1 ppm or more and less than 1,500 ppm.

Electrostatic image developing toner, electrostatic image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method

A carrier for electrostatic image development includes: a core material; and a coating resin layer that contains inorganic particles and covers the core material. The content of the inorganic particles is 10% by mass or more and 60% by mass or less based on the total mass of the coating resin layer. The volume average diameter D (&#x3bc;m) of the inorganic particles and the thickness T (&#x3bc;m) of the coating resin layer satisfy the following relational expression (1): 0.007&#x2264;D/T&#x2264;0.24.

Carrier for electrostatic image development, electrostatic image developer, and process cartridge

A toner for developing an electrostatic charge image contains toner particles, layered-compound particles, and inorganic particles. The percentage Fa of layered-compound particles free from the toner particles is 5% by volume or more and 20% by volume or less.

Toner for developing electrostatic charge image, electrostatic charge image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method

An electrostatic charge image developer contains toner particles, layered-compound particles that are particles of a nitrogen-containing layered compound, and a resin-coated carrier that has magnetic particles and a resin layer covering the magnetic particles. The maximum height Ry of the roughness profile as defined in JIS B0601: 1994 of the surface of the resin-coated carrier is 0.01 &#x3bc;m or more and 0.20 &#x3bc;m or less.

An electrostatic image developing toner includes toner particles, layered compound particles, and inorganic particles. The proportion of irregular-shaped inorganic particles having a circularity of 0.5 or more and 0.9 or less and a size of 0.015 &#x3bc;m or more and 0.350 &#x3bc;m or less to the entire inorganic particles is 2% by number or more and 70% by number or less.

An electrostatic-image developing toner includes toner particles, aggregated silica particles A treated with an oil, and aggregated or non-aggregated silica particles B rendered hydrophobic with a hydrophobizing agent other than an oil. The average particle size Da of the aggregated silica particles A and the average particle size Db of the silica particles B satisfy Da&#x2265;Db. The electrostatic-image developing toner does not include any external additive other than the aggregated silica particles A or the silica particles B, or the electrostatic-image developing toner includes an external additive other than the aggregated silica particles A or the silica particles B, the other external additive having an average particle size smaller than the average particle size Da.

Electrostatic-image developing toner, electrostatic-image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method

An electrostatic charge image developing toner includes: toner particles including an amorphous resin and a crystalline polyester resin including a polycondensate of a linear dicarboxylic acid and a linear dialcohol having 2 to 12 carbon atoms; and an external additive including silica particles having a BET specific surface area of 100 m/g or more. The electrostatic charge image developing toner satisfies the expression: 0.05&#x2264;&#x394;H2/&#x394;H1&#x2264;0.95, wherein &#x394;H1 (mW/g) is an endothermic energy amount based on an endothermic peak derived from the crystalline polyester resin in a first temperature increase process in differential scanning calorimetry according to ASTM D3418-8 (2008), and &#x394;H2 (mW/g) is an endothermic energy amount based on an endothermic peak derived from the crystalline polyester resin in a second temperature increase process in differential scanning calorimetry according to ASTM D3418-8 (2008).

Electrostatic charge image developing toner, electrostatic charge image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method

An electrostatic charge image developer contains a carrier including a core and, on the core, a silicone resin-containing layer serving as a lower layer, and an acrylic resin-containing layer serving as an upper layer, or a carrier including a silicone resin-containing core and an acrylic resin-containing layer on the silicone resin-containing core; strontium titanate particles having an average primary particle size of 20 nm or more and 100 nm or less; and a toner. The percentage of a silicone resin exposed on a surface of the carrier is 0.5 area % or more and 20 area % or less.

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Kanagawa, Japan

Takuro Watanabe