Canon Kabushiki Kaisha

Taiji Katsura

Kentaro Yamawaki

Tsuneyoshi Tominaga

Masamichi Sato

Akira Sugiyama

Yuhei Terui

Katsuyuki Nonaka

Masatake Tanaka

Koji Abe

Hidekazu Fumita

Shohei Kototani

Naoya Isono

Shohei Tsuda

Yusuke Kosaki

Sara Yoshida

Yasushi Katsuta

Tatsuya Saeki

Naotaka Ikeda

Emi Watanabe

Shintaro Kawaguchi

Takashi Kenmoku

Yoshinobu Baba

Atsushi Okuda

Takayuki Itakura

Tsutomu Nishida

Tsutomu Shimano

Kaname Watariguchi

Yojiro Hotta

Akane Masumoto

Ryo Sugiyama

Arihiro Yamamoto

Masaharu Miura

Noriyoshi Umeda

Hideharu Shimozawa

Toshiya Kaino

Harumi Takada

Shinsuke Mochizuki

Shohei Shibahara

Syoji Inoue

Kohei Mizushima

Takayoshi Ootsuka

Chiharu Nakazono

Itaru Kondo

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

The process cartridge is a process cartridge to be removably mounted onto a main body of an electrophotographic apparatus, the process cartridge including: an electrophotographic photosensitive member; a toner; and a developing member, wherein the electrophotographic photosensitive member includes a surface layer that is a polymerized film of a composition containing at least one kind of monofunctional (meth)acrylic compound selected from the group consisting of: a monofunctional (meth)acrylic monomer; and a monofunctional (meth)acrylic oligomer, and at least one kind of tri- or higher functional (meth)acrylic compound selected from the group consisting of: a tri- or higher functional (meth)acrylic monomer; and a tri- or higher functional (meth)acrylic oligomer, wherein the toner contains a toner particle and a hydrotalcite particle as an external additive, and wherein the hydrotalcite particle contains fluorine in filter fitting analysis of STEM-EDS analysis.

Process cartridge and electrophotographic apparatus

A toner comprising: a toner particle comprising a binder resin; and an external additive on a surface of the toner particle, wherein the binder resin comprises a resin having an ester bond, a peak corresponding to boric acid is detected in ATR-IR analysis of the toner particle in an ATR method using germanium as an ATR crystal, and when a dispersed solution obtained by dispersing the toner in an aqueous solution containing a surfactant is subjected to a detachment treatment A including shaking for 300 seconds using a shaker, and when an external additive detached from the toner by the detachment treatment A is denoted as external additive A, a charge amount of the external additive A using a standard carrier (F81) is −0.5 μC/g or less.

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

A toner including: a toner particle containing a binder resin and a colorant; and a fine particle on a surface of the toner particle, wherein the fine particle is a solid and substantially hemispherical shape, and has a substantially flat surface and a curved surface, and wherein a number-average value of a longest diameter 'w' of the substantially flat surface is 10 to 400 nm. An external additive for a toner that is a solid and substantially hemispherical shape, and has a substantially flat surface and a curved surface, wherein a number-average value of a longest diameter “w” of the substantially flat surface is 10 to 400 nm. A fine particle that is a solid and substantially hemispherical shape, and has a substantially flat surface and a curved surface, wherein a number-average value of a longest diameter “w” of the substantially flat surface is 10 to 400 nm.

Toner, external additive for toner, and fine particle

A developing device comprising a developing roller in which a vicinity of an outer surface of a surface layer is hardened, a toner supply roller, and a toner, wherein the developing roller has fine particles comprising an organosilicon compound and having a substantially hemispherical shape on the outer surface, a particle diameter of the fine particles is within a specific range, and the toner comprises silica particles as an external additive and a adhesion rate of the silica particles is 50% or more.

Developing device, cleaning method, process cartridge and electrophotographic image forming apparatus

The present invention provides a toner that can maintain excellent transferability even when a transfer bias is low. The toner includes a toner particle that includes a toner base particle and a plurality of convex portions X existing on a surface of the toner base particle, wherein the convex portion X contains an organic silicon polymer; when a cross-section of the toner is observed with a scanning transmission electron microscope (STEM), and the convex portions X comprise a plurality of convex portions Y each having a convex height H of 40 nm or higher, a number ratio P (H/w) of the a number of the convex portions Yin which a ratio (H/w) of the convex height H to the convex width w is 0.33 or larger and 0.80 or smaller is 70% by number or more with respect to a total number of the convex portions Y.

A toner comprising a toner particle and an external additive, wherein the external additive comprises a composite particle comprising an organosilicon polymer fine particle covering a surface of an alumina particle, a coverage ratio of the surface of the alumina particle with the organosilicon polymer fine particle is 1 to 50 area %, and given A (nm) as a number-average particle diameter of primary particles of the organosilicon polymer fine particle and B (nm) as a number-average particle diameter of primary particles of the alumina particle, following formulae (I) and (II) are satisfied:&#x2264;90&#x2003;&#x2003;(I)100&#x2264;&#x2264;1000&#x2003;&#x2003;(II).

The electrophotographic apparatus and process cartridge comprising an electrophotographic photosensitive member, a cleaning blade, and developing unit containing a toner, wherein the cleaning blade comprising a support member and an elastic member whose portion is abutting a surface of the electrophotographic photosensitive member; the elastic member has an elastic modulus of 15 to 470 MPa with coefficient of variation for the elastic modulus being not more than 7.0%, and the absolute value of a difference between Martens hardness values is not more than 0.30 N/mmas measured under prescribed conditions; the toner contains a toner particle and an external additive whose a number-average primary particle diameter is from 5 to 25 nm, when X1 is a coverage ratio of the toner particle by the external additive and X2 is a theoretical coverage ratio, X1 is 50 to 85 area %, and X1/X2&#x2265;&#x2212;0.0042&#xd7;X1+0.60 is satisfied.

Electrophotographic apparatus and process cartridge

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 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%.

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

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 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

Taiji Katsura