Canon Kabushiki Kaisha

Shohei Kototani

Masamichi Sato

Tsuneyoshi Tominaga

Kentaro Yamawaki

Noriyoshi Umeda

Masatake Tanaka

Tomonori Matsunaga

Taiji Katsura

Shohei Tsuda

Kazuhiro Yamauchi

Yuhei Terui

Takashi Kenmoku

Masahiro Kurachi

Yoshiaki Shiotari

Mayumi Inoue

Toshiaki Takeuchi

Yoshihiro Mitsui

Yuichi Kikuchi

Yuichiro Hirata

Koji Abe

Yasutaka Yagi

Takashi Hiramatsu

Go Shindo

Hideo Kihara

Motonari Ito

Daisuke Baba

Noritaka Toyoizumi

Yasukazu Ikami

Noboru Miyagawa

Kosuke Ikada

Kazunori Hashimoto

Katsuhiro Kojima

Satoshi Otsuji

Akinobu Saito

Yosuke Sugitani

A process cartridge includes a charging unit, (I) wherein the charging unit includes a conductive member, wherein the conductive member includes a conductive layer disposed on an outer surface of a support, the conductive layer has a matrix-domain structure including a matrix and a plurality of domains, the matrix contains a first rubber, the domains contain a second rubber, and (II) wherein the toner includes agglomerates containing silica fine particles and binding components on surfaces of the toner particles, and wherein a relationship of Dms<Ag is satisfied, where Dms is an arithmetic mean of distances between adjacent domains at the outer surface of the conductive roller, and Ag is an arithmetic mean of Feret diameters of the agglomerates.

Process cartridge and process cartridge set

A toner comprising a toner particle comprising a binder resin, wherein the toner particle comprises a condensation product of an organosilicon compound, in time-of-flight secondary ion mass spectrometry of the toner particle, a normalized intensity of silicon ions derived from the condensation product of the organosilicon compound is from 7.00×10to 3.00×10, a normalized intensity of silicon ions after sputtering the toner particle under a specific condition is 6.99×10or lower, the toner comprises a fine particle on the surface of the toner particle, and the fine particle has at least one selected from the group consisting of a specific fine particle of a polyhydric acid metal salt, a strontium titanate fine particle, a titanium oxide fine particle and an aluminum oxide fine particles.

Toner

A cartridge provides comprising: a toner, a developing roller, a supply member and a regular member. The supply member abuts the surface of the developing roller and the regulating member serves to regulate the toner carried on the surface of the developing roller. The cartridge includes a first supply electrode to which a voltage is supplied from outside of the cartridge, with the supply member and the regulating member electrically connected to the same first supply electrode. Additionally, the toner contains a compound A having a structure represented by Formula (1) below,—(CHCHO)—  (1)

Cartridge and image forming apparatus

A toner, comprising a toner particle, wherein the toner particle has a core-shell structure comprising a core particle and a shell on a surface of the core particle, the shell comprises a polymer having monomer units represented by Formula (I) below, the toner comprises a specific external additive A, the external additive A is at least one selected from the group consisting of silica fine particles and organosilicon polymer fine particles, and a ratio of coverage of a surface of the toner particle with the external additive A is 0.3 area % or higher:

An electrophotographic apparatus including an electrophotographic photosensitive member, a charging unit, and a developing unit, wherein the charging unit includes a conductive member disposed to be contactable with the electrophotographic photosensitive member, a conductive layer of the conductive member has a matrix-domain structure, at least some of the domains are exposed at the outer surface of the conductive member, the volume resistivity RI of the matrix is greater than 1.00&#xd7;10&#x3a9;&#xb7;cm and not greater than 1.00&#xd7;10&#x3a9;&#xb7;cm, the matrix volume resistivity R1 is at least 1.0&#xd7;10-times the domain volume resistivity R2, and the developing unit includes a toner, the toner includes a binder resin-containing toner particle and an external additive, and the external additive contains fine particles of a hydrotalcite compound.

Electrophotographic apparatus, process cartridge, and cartridge set

An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging unit, and a developing unit, wherein the charging unit has a conductive member contactable with the electrophotographic photosensitive member, and a conductive layer of the conductive member has a matrix-domain structure; at least some of the domains are exposed at the outer surface; a volume resistivity R1 of the matrix and a volume resistivity R2 of the domains satisfy specific relationship; Martens hardness G1 of the matrix and Martens hardness G2 of the domains satisfy relationship G1&#x3c;G2; the surface roughness Ra of the conductive member is not more than 2.00 &#x3bc;m; the toner has an external additive having a shape factor SF-1 of not more than 115; and A&#x3c;Dms is satisfied where A is the number-average diameter of the external additive and Dms is a distance between adjacent walls between the domains.

A toner including a toner particle containing a binder resin, and an external additive, wherein the external additive contains an organosilicon polymer fine particle, the organosilicon polymer has a structure represented by at least one selected from the group consisting of RSiOand RSiO(wherein Rand Rrepresent organic groups), and in the number particle size distribution of the toner as measured within a particle size range of from 2 to 60 &#x3bc;m, the number-average particle diameter T-Dat which the accumulation from the smallest diameter is 50% is from 6 to 12 &#x3bc;m, the number ratio of toner 4 &#x3bc;m or less in size is from 2% to 5% of the total toner, and the number ratio of toner 3 &#x3bc;m or less in size as a percentage of the total toner 4 &#x3bc;m or less in size is from 25% to 50%.

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 on the conductive member outer surface comprises a matrix and a plurality of domains dispersed in the matrix, at least some of the domains are exposed at the conductive member outer surface, the matrix has a volume resistivity of larger than 1.00&#xd7;10&#x3a9;&#xb7;cm and is 1.0&#xd7;10times or more one of the domains, the developing device comprises the toner comprising a toner particle, fine particles A and B, the fine particle A has a volume resistivity of 1.0&#xd7;10to 1.0&#xd7;10&#x3a9;&#xb7;cm, and the fine particle B is silica fine particle and having a volume resistivity of 1.0&#xd7;10to 1.0&#xd7;10&#x3a9;&#xb7;cm.

Electrophotographic apparatus, process cartridge and cartridge set

A process cartridge includes a seal member contacting an image bearing member upstream in the rotation direction of the image bearing member from a cleaning member and allowing the developer to move from upstream in the rotation direction from the contact part between the seal member and the image bearing to downstream from the contact part while regulating movement from downstream to upstream from the contact part. The developer has surface protrusions containing an organic silicon polymer, wherein either (i) the work function of the seal member is greater than the work function of the developer when the developer has a negative charging polarity and is smaller than the work function of the developer when the developer has a positive charging polarity, or (ii) the absolute value of the difference between the work function of the seal member and the work function of the developer is within a predetermined range.

Process cartridge, image forming apparatus and cleaning apparatus

Provided is a toner including a toner particle and an external additive, wherein the external additive includes a composite particle including a hydrotalcite particle covered on the surface with an organosilicon polymer fine particle, a coverage ratio of the hydrotalcite particle surface by the organosilicon polymer fine particle is from 1% to 50%, and given A (nm) as the number-average particle diameter of the primary particles of the organosilicon polymer fine particle and B (nm) as the number-average particle diameter of the primary particles of the hydrotalcite particle, the toner satisfies the following formula (I) and formula (II):&#x2003;&#x2003;(I)20&#x2264;&#x2264;350&#x2003;&#x2003;(II).

A toner including a toner particle containing a binder resin and an external additive, wherein the external additive contains composite particles of an organosilicon polymer fine particle and a fatty acid metal salt.

Toner and toner manufacturing method

Provided is a toner including a toner particle containing a binder resin, and an external additive, wherein the external additive contains an external additive A and an external additive B, the external additive A is an organosilicon polymer fine particle, the number-average particle diameter of primary particles of the organosilicon polymer fine particle is from 30 to 300 nm, the external additive B is a silica fine particle, the number-average particle diameter of primary particles of the silica fine particle is from 100 to 300 nm, the fixing rate of the external additive A to the toner particle according to a water washing method is less than 30%, and the fixing rate of the external additive B to the toner particle according to the washing method is at least 30%.

A toner containing: a toner particle that contains a binder resin and an external additive, wherein the external additive contains an organosilicon polymer fine particle, the binder resin contains an amorphous resin and a crystalline polyester resin, a content of the crystalline polyester resin in the binder resin is from 5 to 30 mass %, and the crystalline polyester resin contains from 5 to 25 mass % of a component having a molecular weight of not more than 2,500.

A toner comprising a toner particle that contains a binder resin and a wax; in a microcompression test under a maximum load condition of 1.1&#xd7;10N, a force applied to the toner particle when a percentage deformation of the toner particle with reference to a number-average particle diameter of the toner particle at 25&#xb0; C. reaches 15% is 0.10 to 1.00 mN and the force applied to the toner particle when the percentage deformation at 45&#xb0; C. reaches 15% is 0.10 to 0.40 mN; and when the force applied to the toner particle is a variable and the percentage deformation of the toner particle is from 15 to 30%, the rate of increase in the percentage deformation of the toner particle at 25&#xb0; C. and the rate of increase in the percentage deformation of the toner particle at 45&#xb0; C. satisfy specific formula.

A toner including a toner particle containing a binder resin and an external additive, wherein the toner particle contains a polyvalent metal compound, the polyvalent metal compound is at least one selected from the group consisting of aluminum compounds, iron compounds and magnesium compounds, a content of a metal element derived from the polyvalent metal compound in the toner particle is from 0.080 to 20.000 &#x3bc;mol/g, the external additive contains an organosilicon polymer particle having a hydroxyl group, a ratio of a number-average particle diameter of the organosilicon polymer particle to a number-average particle diameter of the toner particle is from 0.0160 to 0.0650, and a content of the organosilicon polymer particle is at least 0.10 mass parts per 100.00 mass parts of the toner particle.

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Suntou-gun, Japan

Shohei Kototani