Fuji Xerox Co., Ltd.

Fujifilm Business Innovation Corp.

Moegi Iguchi

Sakon Takahashi

Yosuke Tsurumi

Soutaro Kakehi

Yutaka Saito

Yuka Yamagishi

Mona Tasaki

Yasuko Torii

Satoshi Inoue

Atsushi Sugawara

Masahiro Takagi

Yoshimasa Fujihara

Koutarou Yoshihara

Takashi Imai

Yasuo Matsumura

Hiroyuki Tanaka

Shuji Sato

Katsumi Daimon

Yuka Zenitani

Yusuke Ikeda

Hirokazu Hamano

Hiroshi Nakazawa

Hideo Maehata

Hiroshi Kamada

Noriyuki Mizutani

Yasuaki Hashimoto

Kazufumi Tomita

Soichiro Kitagawa

Takeshi Tanabe

Masaaki Usami

Hiroaki Saijo

Shigeru Hayashi

Yuta Saeki

Akira Matsumoto

Yasuo Kadokura

Susumu Yoshino

Shintaro Anno

Toshiaki Hasegawa

Masaru Takahashi

Tsuyoshi Murakami

Satoshi Kamiwaki

Yuka Ishihara

Takuro Watanabe

Akihiro Iizuka

Karin Sakai

Tsutomu Furuta

Ryo Nagai

A carrier for electrostatic image development includes: a core material; and a resin coating layer that covers the core material and contains a resin and carbon black particles. The resin coating layer has an average thickness denoted as B μm and contains aggregates of the carbon black particles, the aggregates having equivalent circle diameters denoted as A μm, the aggregates satisfying formula (1) below. In a cross section of the resin coating layer, the ratio of the total area of the aggregates satisfying formula (1) below to the total area of the resin coating layer is 10% or more and 50% or less:0.2×≤0.8×  Formula (1).

Carrier for electrostatic image development, electrostatic image developer, process cartridge, image forming apparatus, and image forming method

An electrostatic image developing toner includes toner particles, an external additive A, and an external additive B. At least the external additive A is deposited on the surfaces of the toner particles. At least the external additive B is deposited on the external additive A. The external additive B includes an aggregate of two or more particles. The coverage of the toner particles with the external additive B is 3% by area or more with respect to the total surface area of the toner particles.

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

An electrostatic image developing toner includes toner particles including a binder resin and a release agent, an external additive A, and an external additive B. At least the external additive A is present on the surface of the toner particles. At least the external additive B is present on the external additive A. The external additive B is an aggregate of two or more particles. The toner particles have an average circularity of 0.8 or more and 0.94 or less. The amount of the release agent present at the surface of the toner particles is 5 area % or more and 30 area % or less based on the total surface area of the toner particles.

An electrostatic image developing toner includes a toner particle, an external additive A, and an external additive B. At least the external additive A is present on the surface of the toner particles. At least the external additive B is present on the external additive A. The number of peaks of the external additive B on the external additive A is 5 or more and 100 or less per 30 &#x3bc;m peripheral length of the toner particle, the peaks having a height from the surface of the toner particle of 80 nm or more and 250 nm or less.

A toner for electrostatic image development includes: toner particles; Si-doped strontium titanate particles; and silica particles. The particle diameter D of at least one peak in a number-based particle size distribution of primary particles of the silica particles is larger than the number-based median diameter Dof primary particles of the Si-doped strontium titanate particles.

Toner for electrostatic image development, electrostatic image developer, and toner cartridge

An electrostatic-image developing toner includes toner particles, inorganic particles externally added to the toner particles, and a low-molecular-weight siloxane having a molecular weight of 200 or more and 600 or less. The low-molecular-weight siloxane includes only a siloxane bond and an alkyl group. The total content of the low-molecular-weight siloxane in the electrostatic-image developing toner is, by mass, 0.01 ppm or more and 5 ppm or less.

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

Provided is an electrostatic charge image developing toner including: toner particles; and strontium titanate particles A and strontium titanate particles B having different average primary particle diameters from each other. The strontium titanate particles B have an average primary particle diameter Db of 10 nm to 100 nm. An average primary particle diameter Da of the strontium titanate particles A and the average primary particle diameter Db of the strontium titanate particles B satisfy a relationship of 10&#x2264;Da/Db&#x2264;100.

Electrostatic charge image developing toner and electrostatic charge image developer

An electrostatic charge image developing toner includes: a toner particle having average circularity of 0.91 or more and 0.98 or less, a silica particle externally added to the toner particle, and a strontium titanate particle that is externally added to the toner particle, that has an average primary particle diameter of 10 nm or more and 100 nm or less, that has average primary particle circularity of 0.82 or more and 0.94 or less, and circularity that becomes 84% of accumulation of the primary particle of more than 0.92.

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

An electrostatic charge image developing toner includes: a toner particle that contains a releasing agent, that has an exposed portion in which the releasing agent is exposed on a surface, and in which a proportion of the exposed portion occupying a surface, which is obtained by X-ray photoelectron spectroscopic analysis is 1 atom % or more and 20 atom % or less; and a strontium titanate particle that is externally added to the toner particle, that is doped with a metal element other than titanium and strontium, and in which an average primary particle diameter is 10 nm or more and 100 nm or less.

A carrier for electrostatic image development includes: resin-coated magnetic particles each including a magnetic particle and a resin layer that covers the magnetic particle; and strontium titanate particles composed of primary particles having an average circularity of 0.82 to 0.94 and an 84% cumulative circularity of more than 0.92.

Carrier for electrostatic image development and electrostatic image developer

An electrostatic charge image developing toner includes a toner particle, a lubricant particle that is externally added to the toner particle, and a strontium titanate particle that is externally added to the toner particle, that has an average primary particle diameter of 10 nm or more and 100 nm or less, that has an average primary particle circularity of 0.82 or more and 0.94 or less, and that has a primary particle circularity that becomes 84% of accumulation of more than 0.92.

An electrostatic charge image developing toner includes: a toner particle and a strontium titanate particle that is externally added to the toner particle, in which an average primary particle diameter of the strontium titanate particle that is present on a surface of the toner particle is 30 nm or more and 100 nm or less, and average primary particle circularity is 0.82 or more and 0.94 or less, and in which circularity that becomes 84% of accumulation of the primary particle is greater than 0.92.

An electrostatic charge image developing toner includes a toner particle; a strontium titanate particle that is externally added to the toner particle and that is doped with a metal element having an electronegativity of 1.3 or less; and a silica particle that is externally added to the toner particle, in which in a case where a detected peak intensity of a metal element having an electronegativity of 1.3 or less is Me-R, a detected peak intensity of strontium is Sr&#x2014;R, a detected peak intensity of silicon is Si&#x2014;R, and an element proportion of strontium is Sr&#x2014;P, Conditions (1) to (3) are satisfied,0.08 kcps&#x2264;Me-R&#x2264;10 kcps,&#x2003;&#x2003;(1)0.1%&#x2264;Sr&#x2014;P&#x2264;3.0%, and&#x2003;&#x2003;(2)0.15&#x2264;Sr&#x2014;R/Si&#x2014;R&#x2264;12.&#x2003;&#x2003;(3)

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.

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.

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Kanagawa, Japan

Moegi Iguchi