Canon Kabushiki Kaisha

Hidekazu Fumita

Kentaro Yamawaki

Taiji Katsura

Yusuke Kosaki

Sara Yoshida

Masashi Kawamura

Noriyoshi Umeda

Yoshinori Tsuji

Minoru Omura

Takayuki Toyoda

Yuhei Terui

Tomonori Matsunaga

Yasuhiro Hashimoto

Naotaka Ikeda

Takeshi Tsujino

Emi Watanabe

Nobuhisa Abe

Satoshi Otsuji

Akira Hashimoto

Masamichi Sato

Hiroshi Koyama

Masatake Tanaka

Tsuneyoshi Tominaga

Shohei Tsuda

Arihiro Yamamoto

Hitoshi Kanda

Toshiya Kaino

Toshiyuki Ugai

Shiro Kuroki

Shinsuke Mochizuki

Junya Asaoka

Syoji Inoue

Satoshi Iki

Naoto Aiko

Itaru Kondo

Takayoshi Ootsuka

Yoshinori Tuji

Kenji Ookuba

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

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.

Toner

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 comprising: a toner particle including a binder resin; and an external additive, wherein the external additive includes an external additive A which is silica fine particles and an external additive B which is a fatty acid metal salt, the external additive A has a specific particle diameter, a coverage ratio of a surface of the toner particle with the external additive A is from 60% to 80%, and where an average theoretical surface area obtained from a number average particle diameter, a particle size distribution and a true density of the toner particle is denoted by C (m/g), an amount of the external additive B is denoted by D (parts by mass) and a coverage ratio of the surface of the toner particle with the external additive B is denoted by E (%), following formulas are satisfied:0.05&#x2264;&#x2264;2.00/()&#x2264;50.0.

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%.

A toner having a toner particle including a binder resin and a wax, wherein the wax includes a specific diester compound; a proportion As of an area occupied by the wax in a region from a surface of the toner particle to 0.5 &#x3bc;m is 15.0% or less; wax domains are observed in the cross section of the toner particle, and an average number of the domains per cross section of one toner particle is from 10 to 2000; when a mass concentration of a polyvalent metal element in the toner particle determined by fluorescent X-ray analysis is denoted by Mi (ppm), Mi is from 3.5 ppm to 1100 ppm; and when a mass concentration of a polyvalent metal element in the toner particle determined by X-ray photoelectron spectroscopy is denoted by Ms (ppm),Mi&#x3e;Ms.

A toner comprising a toner particle having a binder resin, a wax and a colorant, and metal titanate fine particles having a perovskite crystal structure, wherein in cross section observation of the toner using a transmission electron microscope, when a proportion of an area occupied by the wax in a surface layer region from the surface of the toner particle to a depth of 1.0 &#x3bc;m is denoted by As, the As is from 5.0% to 30.0%, and a number average particle diameter of primary particles of the metal titanate fine particles is from 10 nm to 80 nm.

A toner having a toner particle containing a binder resin and a crystalline material, wherein when 'a' is an endothermic quantity deriving from the crystalline material in a DSC of the toner and 'b' is an endothermic quantity deriving from the crystalline material in a DSC of the toner that has been held for 10 hours in an environment with a temperature of 55&#xb0; C. and a humidity of 8% RH, the &#x201c;a&#x201d; and &#x201c;b&#x201d; satisfy a relationship a/b&#x2265;0.85; in a dynamic viscoelastic measurement of a non-melt-molded pellet of the toner, the toner has a temperature range A for which G&#x2033;&#x2264;1&#xd7;10Pa and tan &#x3b4;&#x3c;1 are satisfied; and in a dynamic viscoelastic measurement of a melt-molded pellet of the toner, the toner has a temperature range B for which tan &#x3b4;&#x3e;1 is satisfied within the temperature range A.

A toner which includes a binder resin, a colorant and a hydrocarbon wax has a ratio W1/W2 of the half width W1 (&#xb0; C.) of a endothermic peak derived from melting of the hydrocarbon wax in a first temperature rise process on the toner to the half width W2 (&#xb0; C.) of a endothermic peak derived from melting of the hydrocarbon wax in a second temperature rise process, as measured with a differential scanning calorimeter, with the ratio W1/W2 being not less than 0.50 and not more than 0.90.

Toner and toner production method

A toner is provided that, even in a small amount thereof, gives a satisfactory image density and that is free of image problems, e.g., fogging and offset resistance, even during long-term use and in a high-temperature, high-humidity environment. The toner contains a binder resin, a pigment, and a prescribed azo compound wherein, designating as (A) the solubility of the azo compound in a toluene-hexane solubility test and as (B) the solubility of the binder resin constituting the toner in the toluene-hexane solubility test, the (A) and the (B) satisfy the relationship |(B)&#x2212;(A)|&#x2266;60.

Provided is a toner manufactured in an aqueous solvent, whereby a satisfactory image density can be obtained and the toner laid-on level on a recording medium can be reduced with a normal added concentration of pigment without adding a large quantity of pigment to the toner. The toner is manufactured in an aqueous medium by the suspension polymerization or dissolution suspension method and contains a binder resin, a pigment and an azo compound. The azo compound is a specific azo compound, and the absolute value of the difference in zeta potential between the binder resin and the azo compound is 25 mV or less.

A production apparatus and a production method of toner particles are provided which efficiently and stably reduce the water content of the wet toner particle cake obtained by separating and washing toner particles from toner particle dispersion in a production apparatus of toner particles granulated in a wet process. A wet toner particle cakeformed on a belt filter is aerated and dehydrated with air, and at the same time, sealing unitsprovided on the upstream and downstream sides of the aeration unitcan be operated to efficiently seal aeration air.

Filter cloth traveling type belt filter and production method of toner particles

In a process for producing toner particles through granulation by a wet process, a process for producing toner particles is provided that enables reduction of water content in wet toner particle cakes obtained by separating toner particles from a toner particle dispersion in a good efficiency, followed by washing, and enables efficient wash-away of impurities remaining on the toner particle surfaces so as to promise superior image characteristics. The toner particles are produced through a filtering step in which a slurry which contains toner particles is subjected to solid-liquid separation by means of a belt filter having a pressing aeration means which carries out aeration with pressing, to form wet toner particle cakes.

Process for producing toner particles

In a process for producing toner particles by pre-dispersing at least a colorant and/or a release agent in a first dispersion medium to prepare a first fluid mixture, preparing a second fluid mixture from the first fluid mixture by means of a fine-dispersion machine, and forming toner particles from the second fluid mixture;

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Gotemba, Japan

Hidekazu Fumita