Canon Kabushiki Kaisha

Naotaka Ikeda

Yuhei Terui

Emi Watanabe

Kenji Okado

Yasuhiro Hashimoto

Kazumi Yoshizaki

Takayuki Toyoda

Yushi Mikuriya

Masashi Kawamura

Shinya Yachi

Katsuyuki Nonaka

Taiji Katsura

Hidekazu Fumita

Shohei Shibahara

Takashi Kenmoku

Hironori Minagawa

Kenji Aoki

Waka Hasegawa

Koji Abe

Noriyoshi Umeda

Masashige Tamura

Masanori Seki

Takeshi Kaburagi

Hirofumi Kyuushima

Shintaro Kawaguchi

Nobuhisa Abe

Yoshiaki Wada

The toner has a toner particle that contains a binder resin and a wax, wherein the wax is present in domain form in the interior of the toner particle; the proportion of toner particles for which the position of the wax domains are controlled, is in a prescribed range; using d for a major axis length of the domain having the largest major axis length and using D for a number-average particle diameter of the toner, the d and D satisfy a prescribed relationship; and the ratio between the major axis length and the minor axis length of the domain having the largest major axis length is in a prescribed range.

Toner

A toner has a toner particle that contains a binder resin and a charge control resin, wherein the charge control resin is a polymer that contains a unit A and a unit B, the unit A is a unit derived from 2-acrylamido-2-methylpropanesulfonic acid, the unit B is a unit derived from an electron donor compound that has a polymerizable unsaturated group, and a molar ratio between the unit A and the unit B is from 1.0 to 10.0.

The present invention is a toner including toner particles prepared by forming particles of a polymerizable monomer composition including a polymerizable monomer, a pigment, a pigment dispersant and a crystalline polyester resin in an aqueous medium, and polymerizing the polymerizable monomer, wherein the polymerizable monomer is a polymerizable monomer for preparing a vinyl copolymer, the difference in an SP value between the pigment dispersant and the crystalline polyester resin is &#x2212;1.5 to +0.8, the difference in an SP value between the pigment dispersant an the vinyl copolymer is &#x2212;1.1 to +1.2, the pigment dispersant has a polymer component and an adsorbable component adsorbed to the pigment, the polymer component is a vinyl polymer, the polymer component of the pigment dispersant has a number average molecular weight of 3,000 to 20,000, and a rate of adsorption of the pigment dispersant to the pigment is 30% or more.

A toner is provided that can maintain high transferability even in long-term image output, can maintain high chargeability even in a high temperature and high humidity environment, and rarely causes fogging due to charging failure. The toner contains toner particles produced by a suspension polymerization method or a dissolution suspension method. The volume-average particle diameter (Dv) of silica particles is 50 nm or more and 800 nm or less. The mass loss rate due to heating of the silica particles from 105&#xb0; C. to 200&#xb0; C. is 0.60% or less. The hydrophobicity of the silica particles is 5% or more and less than 40%.

Toner and method for producing toner

A toner containing toner particles, each of which contains a binder resin and a colorant, and silica particles, wherein the silica particles have a volume average particle diameter (Dv) of 70 nm or more and 500 nm or less, the variation coefficient of diameters of the silica particles, based on volume distribution thereof, is 23% or less, and wherein when the silica particles are heated from 105&#xb0; C. to 200&#xb0; C., the ratio of mass decrease is 0.60% or less.

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 toner having toner base particles each of which contains at least a binder resin and a colorant, and silica titania composite particles. The silica titania composite particles contain silica in an amount of from 55.0% by mass to 85.0% by mass; and, in a chart obtained by the measurement by X-ray diffraction of the silica titania composite particles and where, in respect of a peak having the highest diffraction intensity and a peak having the next-highest diffraction intensity among peaks present in the range of 2&#x3b8;=24.0 to 29.0, the value of area of the peak on the lower-angle side is represented by Xa and the value of area of the peak on the higher-angle side is represented by Xb, the ratio of Xa/Xb is from 95/5 to 75/25.

A toner is provided which has toner particles and a fine silica powder mixed by external addition to the toner particles. The toner has a weight average particle diameter of 4.0 to 9.0 &#x3bc;m. The fine silica powder is subjected to hydrophobic treatment with dimethylsilicone oil, and has, in particle size distribution based on volume, a peak at which cumulative frequency is largest, in the measurement range of 0.02 &#x3bc;m to 1,000.00 &#x3bc;m; the cumulative frequency of 0.10 &#x3bc;m to less than 1.00 &#x3bc;m being 7.0% or less, and, the fine silica powder fulfills the following conditions:

Toner and image forming method

In an image forming apparatus having at least one single electrostatic latent image bearing member and a plurality of image forming units each having a replenishing developer cartridge and a developing assembly, at least one of the image forming units is a special-color image forming unit having a special-color replenishing developer cartridge containing a special-color replenishing developer, and at least one of the other image forming unit is a non-special-color image forming unit having a non-special-color replenishing developer cartridge containing a non-special-color replenishing developer. The special-color replenishing developer cartridge has a volume larger than the volume of the non-special-color replenishing developer cartridge, and the special-color replenishing developer contains a toner and a carrier.

Image forming apparatus, and replenishing developer kit

In an image forming apparatus having a powder transport mechanism including a powder container and a powder transport means which rotates relative to the powder container, the powder transport means has the rotation center substantially on the axis of the powder container, and the space between the inner wall surface of the powder container and the powder transport means is sealed with magnetic particles held by a magnetic-filed generation means. The magnetic particles have a specific saturation magnetization &#x3c3;s and a specific value of A&#xd7;&#x3c3;where the residual magnetic flux density of the magnetic-field generation means is represented by A in a specific range and the magnetization intencity of the magnetic particles in a magnetic field with the residual magnetic flux density A is represented by &#x3c3;.

Image forming apparatus

An electrostatic latent image on an image-bearing member is developed with a two-component developer comprising a toner and a carrier stored in a developer vessel while supplying as required a replenishing developer to the developer vessel. The replenishing developer comprises 1 wt. part of a carrier and 2-50 wt. parts of a toner, wherein the carrier is a magnetic fine particle-dispersed resin carrier comprising at least inorganic compound particles and a carrier binder resin, and the toner has a weight-average particle size of 3 to 10 &#x3bc;m and contains 1 to 40 wt. % of solid wax.

Replenishing developer and developing method

In a full-color image-forming method having at least a charging step, a latent-image-forming step, a developing step of developing an electrostatic latent image by the use of a developer; a transfer step, and a fixing step, the developer comprises a plurality of color developers and a black developer. The color developers are each a two-component developer for full-color image formation which has i) a color toner having color toner particles containing at least a binder resin, a colorant and a wax and ii) a carrier for the color developer. The black developer is a two-component developer for full-color image formation which has i) a black toner having black toner particles containing at least a binder resin, carbon black and a wax and ii) a carrier for the black developer. The carrier for the black developer has a larger absolute value of charge quantity when the same toner is used, than the respective carriers for the color developers.

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Suntou-gun, Japan

Naotaka Ikeda