Canon Kabushiki Kaisha

Shohei Tsuda

Katsuhisa Yamazaki

Koji Nishikawa

Takashi Matsui

Keisuke Tanaka

Naoki Okamoto

Daisuke Yoshiba

Yojiro Hotta

Kozue Uratani

Noriyoshi Umeda

Takayuki Itakura

Kosuke Fukudome

Tsuneyoshi Tominaga

Taiji Katsura

Kazuo Terauchi

Motohide Shiozawa

Shohei Kototani

Takeshi Naka

Kazuhiro Yamauchi

Shotaro Nomura

Hiroki Akiyama

Yuujirou Nagashima

Mariko Yamashita

Satoshi Arimura

Masami Fujimoto

Tomonori Matsunaga

Masahiro Kurachi

Takuya Mizuguchi

Ryo Nagata

Masamichi Sato

Yoshinobu Baba

Masatake Tanaka

Kentaro Yamawaki

Masaharu Miura

Motonari Ito

Hideo Kihara

Hidekazu Fumita

Tatsuya Saeki

Noboru Miyagawa

Tomoya Nagaoka

Shintaro Kawaguchi

Satoshi Otsuji

Kazuki Kaneko

A toner comprising: a toner particle comprising a binder resin and boric acid; and an external additive A having a primary particle major diameter of 80 to 200 nm, wherein in ATR-IR analysis of the toner particle in an ATR method using germanium as an ATR crystal, a peak corresponding to boric acid is detected, the average value of a shape factor SF-1 of the external additive A is 105 to 250, and the average value of a shape factor SF-2 of the external additive A is 102 to 250.

Toner and method for producing toner

A toner comprising a toner particle comprising a binder resin, a crystalline material A, and a crystalline material B, wherein the binder resin contains a resin M in an amount of 70 mass % or more relative to the binder resin, the crystalline material A has a melting point of 50.0° C. to 100.0° C., and when, the difference between the SP value of the resin M and material A is designated as ΔSPAM, the difference between the SP value of the resin M and crystalline material B is designated as ΔSPBM, the difference between the SP value of the crystalline material A and crystalline material B is designated as ΔSPAB, the peak molecular weight of the crystalline material A and crystalline material B is designated as MpA and MpB each, the formulae (1) to (3) are satisfied:50≤≤450  (1)≤800  (2)Δ≤0.26  (3).

Toner

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 including a binder resin, wherein fine particles A and B are present on a surface of the toner particle; the fine particles A are a fatty acid metal salt; the fine particles B have a specific volume resistivity; an average theoretical surface area of the toner particle, an amount of the fine particles A, and a coverage ratio of the toner particle surface by the fine particles A satisfy a specific relationship; the amount of the fine particles B is in a specific range; and a proportion F of an area occupied by a part of the fine particles B embedded in a surface vicinity region of the toner in a total area occupied by the fine particles B present in a cross section of one particle of the toner is 50% by area or more.

A toner comprising a toner particle including a binder resin and a colorant and an external additive, wherein the external additive contains an external additive A having a Feret diameter of 60 to 200 nm, the external additive A is inorganic fine particles or organic-inorganic composite fine particles, adhesion index of the external additive A to the toner is 0.00 to 3.00, and penetration depth b and protrusion height c satisfy Relational expressions (1) and (2) below, where b (nm) denotes penetration depth of the external additive A, at a portion of the external additive A penetrating into the toner particle interior from the surface thereof, and c (nm) denotes a protrusion height of the external additive A at that portion, in an observation of an image resulting from image processing of a cross section of the toner using TEM;60&#x2264;&#x2264;200&#x2003;&#x2003;(1),0.15&#x2264;/()&#x2264;0.30&#x2003;&#x2003;(2).

A toner comprising: a toner particle that contains a release agent-containing toner base particle, and an organosilicon polymer on a toner base particle surface, and an external additive A, the organosilicon polymer has a T3 unit structure; the organosilicon polymer forms protruded portions on the toner base particle surface; the number-average value of the protrusion height H is from 30 nm to 300 nm; the ratio of the number-average primary particle diameter R of the external additive A to the number-average value of the protrusion height H is from 1.00 to 4.00; the number-average primary particle diameter R of the external additive A is from 30 nm to 1,200 nm; and, in an image obtained by observing the toner surface with SEM, the area percentage for the bright region area in the image with reference to the total area of the image is from 30.0% to 75.0%.

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

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 comprising: a toner particle that contains a binder resin and a colorant: and an external additive, wherein (1) the average circularity of the toner is at least 0.960; (2) the fixing ratio of the external additive on the toner particle is from 75% to 100%; and (3) in a differential curve obtained by the differentiation, by load, of a load-displacement curve where the horizontal axis is load (mN) and the vertical axis is displacement (&#x3bc;m), the load-displacement curve being provided by measurement of the strength of the toner by a nanoindentation procedure, a load A that provides a maximum value in the differential curve in a load region from 0.20 mN to 2.30 mN is from 1.15 mN to 1.50 mN.

A toner comprising a toner particle that contains a binder resin and a colorant, wherein (1) an average circularity of the toner is at least 0.960, (2) an onset temperature T&#x3b5; (&#xb0; C.) of a storage elastic modulus E' of the toner, as determined by a powder dynamic viscoelastic measurement, is from 50&#xb0; C. to 70&#xb0; C., and (3) in a differential curve obtained by differentiation, by load, of a load-displacement curve provided by measurement of the strength of the toner by a nanoindentation procedure, with the horizontal axis being load (mN) and the vertical axis being displacement (&#x3bc;m), the load X that provides the maximum value in the differential curve in the load region from 0.20 mN to 2.30 mN is from 1.00 mN to 1.50 mN.

A toner is provided, where good cleanability is exhibited, abrasion variations of the photo conductor surface is reduced, and contamination of a charge member is reduced. The toner includes toner particles and organic-inorganic composite fine particles on the toner particle surfaces, wherein each of the organic-inorganic composite fine particles is a particle in which inorganic fine particles are exposed at the surfaces of vinyl based resin particles in such a way that convex portions derived from the inorganic fine particles are formed on the surfaces, the average circularity of the toner is 0.960 or more, and the absolute value Q of the amount of triboelectricity of the toner measured by a two-component method and the electrostatic adhesion F of the toner satisfy 0.003&#x2264;F/Q&#x2264;0.040.

Toner and image forming method

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

Provided is a toner comprising a toner particle including a binder resin, an amorphous polyester, and a colorant, wherein the binder resin includes a vinyl resin, the toner has a softening point of at least 110&#xb0; C. and not more than 140&#xb0; C., an amount of the amorphous polyester is at least 4.0 parts by mass and not more than 30.0 parts by mass with respect to 100 parts by mass of the binder resin, and a temperature T at which an area increasing rate of one toner particle sample becomes 1.40, is not more than 110&#xb0; C., and a slope of the area increasing rate with respect to a temperature in the range of the area increasing rate of 1.40 to 2.00 is not more than 0.07.

Toner, developing device, and image forming apparatus

A toner comprising a toner particle containing a binder resin, a colorant, an amorphous polyester, and a crystalline polyester, wherein the binder resin contains a vinyl resin; the amorphous polyester has a monomer unit derived from a linear aliphatic dicarboxylic acid having 6 to 12 carbons, and a monomer unit derived from a dialcohol; the content of the monomer unit derived from a linear aliphatic dicarboxylic acid having 6 to 12 carbons is 10 to 50 mol % with reference to the total monomer units derived from a carboxylic acid in the amorphous polyester; and in a cross section of the toner particle, the vinyl resin constitutes a matrix and the amorphous polyester constitutes domains, and the crystalline polyester is present in the interior of the domains.

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Suntou-gun, Japan

Shohei Tsuda