Canon Kabushiki Kaisha

Other

Hirohide Tanikawa

Hiroyuki Fujikawa

Tsutomu Onuma

Masaki Uchiyama

Toshiaki Nakahara

Yasutaka Akashi

Masatsugu Fujiwara

Masami Fujimoto

Masaaki Taya

Makoto Unno

Takayuki Itakura

Kiichiro Sakashita

Satoshi Yoshida

Takakuni Kobori

Nobuyoshi Sugahara

Hiroaki Kawakami

Kazuyoshi Hagiwara

Yoshinobu Baba

Tetsuya Ida

Yasuhiro Ichikawa

Nobuyuki Okubo

Kaori Hiratsuka

Kazuhiko Hayami

Akira Hashimoto

Katsuhisa Yamazaki

Nozomu Komatsu

Koh Ishigami

Yojiro Hotta

Yasuo Mitsuhashi

Keita Nozawa

Shinji Doi

Tsuneo Nakanishi

Yoshihiro Ogawa

Wakashi Iida

Makoto Kanbayashi

Yuko Sato

Kazunori Kato

Minoru Shimojo

Rika Shinba

Naoki Matsushige

Yoshinobu Joh

Takashige Kasuya

Naoki Okamoto

Hiroshi Yusa

Shuhei Moribe

Satoshi Matsunaga

Kazuo Terauchi

Kuniko Kobayashi

Minekazu Endo

Masashi Jinbo

Katsuhiko Tanaka

Kunihiko Nakamura

Tsutomu Kukimoto

Noriyoshi Umeda

Tadashi Doujo

Takaaki Kotaki

Takayuki Nagatsuka

Takeshi Naka

Nene Shibayama

Yuichi Mizoh

Naoto Kitamori

Takeshi Ohtake

Hideto Iida

Seiichi Takagi

Takeshi Ootsu

Provided is a developer for replenishment capable of forming a high-quality image even upon duration. The developer for replenishment includes at least a toner and a magnetic carrier, and in the developer for replenishment, 1 part by mass of the magnetic carrier is blended with 2 to 50 parts by mass of the toner, and the magnetic carrier contains a ferrite core and a resin component, has a true specific gravity of 2.5 to 4.2 g/cm, has a 50% particle diameter on a volume basis (D50) of 15 to 70 &#x3bc;m, and has an average circularity of 0.850 to 0.950, the average circularity having a coefficient of variation of 1.0 to 10.0%.

Developer for replenishment and image forming method

The present invention relates to a toner which has good property such as fixability, coloring power, developability, durability, and environmental stability and so on. More specifically, the present invention relates to a color toner containing at least a binder resin, a colorant, and a wax, in which: a wax concentration of an extract obtained by dispersing the toner into n-hexane at a concentration of 15 mg/cmat 23&#xb0; C. and by subjecting the resultant dispersion to extraction treatment at 23&#xb0; C. for 1 minute is in the range of 0.080 to 0.500 mg/cm; an average circularity of particles each having a circle-equivalent diameter of 3 &#x3bc;m or more in the toner is in the range of 0.925 to 0.965; and a content of the wax is in the range of 1 to 15 parts by mass with respect to 100 parts by mass of the binder resin.

Color toner and two-component developer

Provided a toner including at least: toner particles each containing at least a binder resin, a release agent, and a colorant; and an inorganic fine powder, in which: a degree of aggregation Yat a time of compression (200 kpa) of the toner satisfies a relationship of 15&#x2266;Y&#x2266;35, and a degree of aggregation Yat a time of non-compression of the toner satisfies a relationship of 7&#x2266;Y&#x2266;15; and a highest endothermic peak of the toner is present in a temperature range of 30 to 200&#xb0; C. in an endothermic curve measured with a differential scanning calorimeter (DSC), and a peak temperature Tsc (&#xb0; C.) of the highest endothermic peak satisfies a relationship of 60&#x2266;Tsc&#x2266;130.

Toner and image forming method

The present invention provides a yellow toner which is excellent in transparency of an image formed on an OHP sheet, excellent in color reproducibility even when a light-pressure fixing unit is employed, excellent in coloring power and charge property, and is reduced in occurrence of filming. The present invention also provides a yellow toner having excellent durability and capable of contributing to the simplification or miniaturization of the constitution of an image forming apparatus. The yellow toner of the invention comprises a binder resin and a colorant, the binder resin contains at least a polyester unit, and the toner in the powder state has a lightness L* satisfying the relationship of L*&#x3e;87 and has a chromaticity b* satisfying the relationship of 106&#x3c;b*&#x3c;120.

Yellow toner, image forming apparatus and a method for producing a toner

A color toner that comprises at least a binder resin, a colorant and a release agent, wherein the binder resin has at least a polyester unit and is synthesized in the presence of a tin compound as a catalyst represented by the general formula (1):(RCOO)Sn&#x2003;&#x2003;(1)wherein, R is an alkyl group of 5 to 15 carbon atoms. The toner is excellent in charge build-up, resistance to high temperature offset, color reproducibility and transparency.

Color toner

A magenta toner is provided which contains at least a binder resin, a colorant, and a wax, in which a maximum heat-absorption peak temperature as measured using a differential scanning calorimeter, a reflectance at a predetermined wavelength when measured in a powder state by spectroscopic analysis, and lightness when measured in a powder form are in specific ranges. A full-color image is formed using the magenta toner as a pale magenta toner in combination with a deep magenta toner. According to the present invention, it becomes possible to form a vivid image which has reduced graininess and roughness from a low-density region to a high-density region, ensures a sufficient fixing temperature region, has a color reproduction range wider that the conventional one, and has high transparency on an OHP sheet.

Toner and method for forming image

The present invention provides a toner improved in dispersibility of a colorant in the toner particles and excellent in the color reproducibility including color mixability and transparency. The toner is also excellent in the stability in long-term of the chargeability and capable of forming images maintaining high image quality. The present invention provides a toner for forming a full-color image which includes at least toner particles containing a binder resin, a colorant and a wax, and inorganic fine particles, wherein the binder resin comprises a resin having polyester units which is synthesized by use of an aromatic carboxylic acid titanium compound as a catalyst, and the inorganic fine particles comprise fine titanium oxide particles.

Toner

Magenta toner

In a color toner having toner particles which have toner base particles containing a binder resin, a colorant and a wax, and inorganic fine particles, (i) in the toner base particles, particles having a circle-equivalent diameter of 3.00 &#x3bc;m or more as measured with a flow type particle image analyzer have an average circularity of from 0.920 or more to less than 0.950, (ii) in the particles having a circle-equivalent diameter of 3.00 &#x3bc;m or more in the toner base particles, particles having a circularity of 0.960 or more are in a number frequency cumulative value of 40% or less; and (iii) in the particles having a circle-equivalent diameter of 3.00 &#x3bc;m or more in the toner base particles, particles having a circularity of 0.920 or less are in a number frequency cumulative value of 30% or less. Also disclosed is a full-color image forming method making use of the toner.

A magnetic carrier composed of carrier particles is provided in which each carrier particle has a carrier core including magnetic fine particles and a binder resin with the carrier core surface being coated with a coat material containing a coat resin. In the magnetic carrier, Fatom/Catom and (Fatom/Catom)/(Fcalc/Ccalc) are respectively in specific ranges, wherein Fatom and Catom represent respectively a fluorine element abundance ratio and a carbon element abundance ratio at the magnetic carrier particle surface, and Fcalc and Ccalc represent respectively a fluorine element abundance ratio and a carbon element abundance ratio which are calculable from the molecular structure of the coat resin. In addition, a two-component developer is provoded including the magnetic carrier and a toner having a specific contact angle against water.

Magnetic carrier and two-component developer

The present invention provides a cyan toner including: one or plural heat-absorption peaks in a temperature range of 30 to 200&#xb0; C. in a heat-absorption curve obtained by using a differential scanning calorimeter; a maximal value of a maximum heat-absorption peak temperature in the range of 65 to 150&#xb0; C.; and a reflectance of 45 to 80% at a wavelength of 500 nm, a reflectance of 5 to 30% at a wavelength of 600 nm, and a brightness L* of 45 to 75, when measured in a powder form by spectroscopic analysis. The present invention thus provides a cyan toner capable of forming an image with reduced graininess and roughness from a low-density region to a high-density region and ensured a sufficient fixing temperature region, and a method for forming an image using the cyan toner.

Cyan toner and method for forming an image

To provide a color toner which is effective in mitigating contamination of a charging member, which is good at low temperature fixing in high-speed copying, and which is excellent in blocking resistance and electrification stability in continuous copying. Provided is a color toner containing at least a binder resin, a colorant, and a releasing agent, in which: (i) the binder resin contains at least a polyester unit; (ii) a weight average particle diameter of the color toner is greater than 6.5 &#x3bc;m and equal to or less than 11 &#x3bc;m; (iii) an average circularity A of particles in the color toner each having a circle-equivalent diameter of 3 &#x3bc;m or more satisfies the relationship of 0.915&#x2266;A&#x2266;0.960; (iv) a permeability B (%) of the color toner in a 45 vol % aqueous solution of methanol satisfies the relationship of 10&#x2266;B&#x2266;70; and (v) an endothermic curve obtained through differential thermal analysis (DSC) measurement of the color toner has one or multiple endothermic peaks in the temperature range of 30 to 200&#xb0; C., and a temperature Tsc of the highest endothermic peak of the one or multiple endothermic peaks satisfies the relationship of 65&#xb0; C.&#x3c;Tsc&#x3c;105&#xb0; C.

In a toner having a polyester resin as a binder resin component, and a colorant, the toner contains (a) in the binder resin component, from 20.0% by weight to 65.0% by weight of a tetrahydrofuran-insoluble matter A1 in 6-hour extraction and from 35.0% by weight to 80.0% by weight of a tetrahydrofuran-soluble matter A2 in 6-hour extraction, (b) in the binder resin component, from 10.0% by weight to 30.0% by weight of a tetrahydrofuran-insoluble matter B1 in 16-hour extraction and from 70.0% by weight to 90.0% by weight of a tetrahydrofuran-soluble matter B2 in 16-hour extraction, and (c) in the binder resin component, from 0.5% by weight to 3.0% by weight of an orthodichloro-benzene-insoluble matter C1 in 6-hour extraction at 185&#xb0; C. and from 97.0% by weight to 99.5% by weight of an orthodichlorobenzene-soluble matter C2 in 6-hour extraction at 185&#xb0; C. The proportion of C1 to B1, C1/B1, is from 0.06 to 0.15, and the A1, B1 and C1 satisfy the following expression (1):A1&#x3e;B1&#x3e;C1.&#x2003;&#x2003;Expression (1)A process cartridge makes use of this toner.

Toner, and process cartridge

A toner showing a high transferability and suitable for use in cleanerless image forming system is formed of toner particles comprising at least a binder resin and magnetic iron oxide. The toner is characterized by a specific circularity distribution relative to its weight-average particle size and a controlled degree of surface-exposed magnetic iron oxide providing an extract solution with hydrochloric acid showing an absorbance of 1.0-2.5 at a wavelength of 340 nm. The toner is suitably produced by a production system including a rotary mechanical pulverizer and a one-pass surface treatment apparatus for continuously applying a mechanical impact force to pulverized toner particles therein.

Dry toner, toner production process, image forming method and process cartridge

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Shizuoka, Japan

Hirohide Tanikawa