Canon Kabushiki Kaisha

Takuya Mizuguchi

Hiroyuki Tomono

Kosuke Fukudome

Yojiro Hotta

Yoshitaka Suzumura

Kozue Uratani

Kazuo Terauchi

Motohide Shiozawa

Osamu Matsushita

Takeshi Naka

Yuta Komiya

Takashi Matsui

Kazuhiro Yamauchi

Katsuhisa Yamazaki

Masami Fujimoto

Kenta Kamikura

Tetsuya Kinumatsu

Masahiro Kurachi

Keisuke Tanaka

Takayuki Itakura

Koji Nishikawa

Naoki Okamoto

Shuntaro Watanabe

Shotaro Nomura

Shohei Tsuda

Shingo Ito

Tsuneyoshi Tominaga

Akane Masumoto

Shuhei Moribe

Hiroki Akiyama

Atsuhiko Ohmori

Shunsuke Matsushita

Yasukazu Ikami

Yuujirou Nagashima

Issei Imamura

Tatsuya Saeki

Hiroki Kagawa

Dai Nozaki

Kousuke Yamamoto

Tomoko Sugita

Sho Kimura

The present disclosure provides a toner that achieves both high image gloss and high image loadability. The toner includes a toner particle that includes: a styrene-acrylic resin having a unit represented by the formula (1); and an ester compound A, wherein the ester compound A is an ester compound represented by the formula (2) or the formula (3): and an absolute value of a difference between SPb (J/cm)that is an SP value of the styrene-acrylic resin and SPw1 (J/cm)that is an SP value of the ester compound A is 1.00 or larger and 2.00 or smaller.

Toner

A toner including a toner particle containing a binder resin and an ester compound, wherein the binder resin contains a styrene-acrylic-based resin, the styrene-acrylic-based resin contains a specific unit, the ester compound has a specific structure, and a molar ratio of the specific unit to the ester compound is 0.5 to 1.5.

A toner comprising a toner particle comprising a binder resin, and an ester wax A having a specific structure, wherein in a diffraction spectrum obtained by an X-ray diffractometer after the toner has been allowed to stand at 120° C. for 5 minutes and then at 60° C. for 5 minutes, assuming that a spectrum having a maximum peak in a range where 2θ is from 5.45° to 5.95° is P1 and an integrated intensity of the P1 is S1, and a spectrum having a maximum peak in a range where 2θ is from 21.45° to 21.95° is P2 and an integrated intensity of the P2 is S2, relationships of formulas (2) and (3) below are satisfied.1/2≤0.25  (2)2≥1000  (3)

A toner comprising a toner particle comprising a binder resin and a crystalline resin, wherein the binder resin comprises an amorphous resin, when the toner is measured with a temperature-modulated differential scanning calorimeter, at least one endothermic peak derived from the crystalline resin is present in a temperature range from 55.0&#xb0; C. to 95.0&#xb0; C. in a total heat flow; and a ratio of an endothermic quantity of the endothermic peak in a reversing heat flow to an endothermic quantity of the endothermic peak in the total heat flow is 50.0% or more, a glass transition temperature Tg1st obtained in the reversing heat flow in a first temperature rise and a glass transition temperature Tg2nd obtained in a reversing heat flow in a second temperature rise satisfy Tg1st&#x2212;Tg2nd&#x2265;7.0&#xb0; C.

An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging device and a developing device, wherein the charging device comprises a conductive member arranged to be capable of contacting the electrophotographic photosensitive member, the conductive layer at the outer surface of the conductive member comprises a matrix and a plurality of domains dispersed in the matrix, at least some of the domains are exposed at the outer surface of the conductive member, the matrix has a volume resistivity R1 of larger than 1.00&#xd7;10&#x3a9;&#xb7;cm, the volume resistivity R1 of the matrix is 1.0&#xd7;10times or more a volume resistivity R2 of the domains, the developing device comprises the toner comprising a toner particle and a silica fine particle, and a coverage ratio of the toner surface with the silica fine particles is from 62.0% by area to 100.0% by area as determined by X-ray photoelectron spectroscopy.

Electrophotographic apparatus, process cartridge and cartridge set

An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging device and a developing device, wherein the charging device comprises a conductive member arranged to be capable of contacting the electrophotographic photosensitive member, a conductive layer of the conductive member comprises a matrix domain structure, at least a part of the domains Dt is exposed at the conductive member outer surface, the matrix has a volume resistivity R1 of larger than 1.00&#xd7;10&#x3a9;&#xb7;cm, the domains Dt has a volume resistivity of smaller than R1, the developing device comprises the toner, domains Dc formed of the crystalline material exist in a cross section of the toner, distances between adjacent wall surfaces of the domains Dc is from 30 to 1,100 nm, and a weight-average particle diameter D4 of the toner and distances Dms between adjacent wall surfaces between the domains Dt satisfies D4&#x2265;Dms.

Electrophotographic apparatus, process cartridge, and cartridge set

A toner comprising: a toner particle containing a binder resin and a colorant; and an external additive, wherein the external additive is a composite particle having an organic substance and an organosilicon polymer coating layer on the surface of the organic substance, and when a curve for the variation (dE'/dT) in the storage elastic modulus E&#x2032; of the toner with respect to temperature T [&#xb0; C.] is obtained on the basis of a curve of the temperature T&#x2014;the storage elastic modulus E&#x2032; [Pa] of the toner, as determined by powder dynamic viscoelasticity measurements of the toner, the relative minimum value on the lowest temperature side between the onset temperature and 90&#xb0; C. is &#x2212;1.35&#xd7;10or less.

Toner, and external additive for toner

A toner comprising an external additive A, and a toner particle containing a binder resin and a colorant, wherein the external additive A: i) is an external additive that has a charge control agent on the surface thereof; ii) has a wall friction angle &#x3b8; calculated from the following formula (1) of not more than 25.0&#xb0;&#x3b8;=&#x3c4;/5.0&#x2003;&#x2003;formula (1);iii) has a number-average particle diameter (D1) of primary particles of at least 70 nm and not more than 500 nm; and iv) has a solidity as given by the following formula (2) of at least 0.40 and not more than 0.90solidity=area of external additive/area of region encompassed by envelope for external additive&#x2003;&#x2003; formula (2).

Toner and method of producing toner

A toner having a toner particle containing a binder resin, an amorphous polyester, and a colorant, wherein a softening point of the toner is at least 110&#xb0; C. and not more than 140&#xb0; C.; an integrated value f1 for stress of the toner is not more than 10 g&#xb7;m/sec, as measured using a tack tester, with a temperature for a probe end being 150&#xb0; C. and a press holding time being 0.01 seconds; and an integrated value f2 for stress of the toner is at least 30 g&#xb7;m/sec, as measured using a tack tester, with a temperature for a probe end being 150&#xb0; C. and a press holding time being 0.1 seconds.

Toner, developing apparatus, and image-forming apparatus provided with toner

A toner comprising: a toner particle containing a toner base particle containing a binder resin and a colorant, and a resin particle fixed to a surface of the toner base particle; and an inorganic fine particle A, wherein the surface of the toner particle has protruded portions originating in the resin particle, an average length (D) of long sides of the protruded portions is 50 nm to 300 nm, an average Height (H) of the protruded portions is 25 nm to 250 nm, the average long-side length and the average height of the protruded portions satisfies a specific relationship, and an average value of a compactness of the inorganic fine particle A is 0.40 to 0.80, and the attachment rate of the inorganic fine particles A is 0.1% to 5.0% by area.

Provided is a magnetic toner in which enhancement of initial transfer efficiency and transfer efficiency that is stable during a long-term use are achieved by simultaneously suppressing the friction force between the toner and a drum and the cohesion between toners, and further the degradation in chargeability and fluidity caused by the deterioration of the toner. The magnetic toner includes: a magnetic toner particle; a first external additive; and a second external additive. The first external additive includes an organic-inorganic composite fine particle, a plurality of convexes derived from an inorganic fine particle being present on a surface of the organic-inorganic composite fine particle, and has a number-average particle diameter of 50 nm or more and 500 nm or less. The second external additive includes a silica fine particle and has a number-average particle diameter of 5 nm or more and 30 nm or less. A shear load calculated from a rotation torque is 0.50 kPa or more and 2.00 kPa or less when a disc-shaped disc is pressed against a surface of a magnetic toner powder layer, the magnetic toner powder layer being produced by applying a vertical load of 9.0 kPa to the magnetic toner, under a vertical load of 5.0 kPa, and the disc which is being pressed is rotated, and an absolute value |&#x3b6;(T)&#x2212;&#x3b6;(A1)| of a difference between a zeta potential &#x3b6;(T) of the magnetic toner particle dispersed in water and a zeta potential &#x3b6;(A1) of the first external additive dispersed in water is 50 mV or less.

Magnetic toner

Growing community of inventors

Suntou-gun, Japan

Takuya Mizuguchi