Fuji Xerox Co., Ltd.

Fujitsu Corporation

Other

Ricoh Company, Ltd.

Harima Chemicals, Incorporated

Nippon Carbide Industries Co., Inc.

Yoshimichi Katagiri

Yasushige Nakamura

Tomoaki Tanaka

Seijiro Ishimaru

Yuzo Horikoshi

Masakazu Kinoshita

Masae Nakamura

Norio Sawatari

Shinichi Yaoi

Hiroshi Yamashita

Osamu Uchinokura

Satoshi Takezawa

Takashi Yamamoto

Katsuji Ebisu

Shinichi Kuramoto

Hachiro Tosaka

Sadaaki Yoshida

Kazuhiko Kido

Hitoshi Kusaba

Eiji Sakurai

Takashi Yoshida

Toshiaki Narusawa

Yasufumi Nakamura

Takahiro Kashikawa

Hachiroh Tosaka

Makoto Koshi

Hiroaki Naito

Hidenori Fujioka

Shin-ichi Kuramoto

Kazuyuki Kishimoto

Kazuya Hamada

Masahiro Nishihata

Haruo Kuroda

Tetsuro Baba

Yuko Ohyama

Ikuya Yamabata

Yumi Fujisaki

Masaki Nagaoka

Mutsuo Watanabe

Yoshimi Mizoguchi

Yasuo Yamagishi

Yuji Sato

Hiromichi Kobayashi

Jun Saito

Masahisa Ochiai

Yojiro Kumagae

Makoto Fukuda

Tsuyoshi Itagoshi

Hiroyuki Sasaki

Tsuneo Watanuki

Yoshihiro Makuta

Yasuharu Takeuchi

Masatoshi Maruyama

Seijirou Ishimaru

Kazuhiko Hamazoe

Takeshi Ogino

Hidenori Nitta

Sonoo Matsuoka

Yoshiaki Ishibashi

Hiroichi Ishihara

A magnetic black toner for electrophotography comprising a binding resin, a magnetic substance, and a pigment, wherein the pigment is at least one of phthalocyanine pigment and Mn containing hematite, and the content ratio of the magnetic substance and the pigment in the toner satisfy the following formulae: 10&#x2266;A&#x2266;30, 0.1&#x2266;B&#x2266;3, 5&#x2266;C&#x2266;40, wherein A denotes the content ratio (mass %) of the magnetic substance in the toner, B denotes the content ratio (mass %) of the phthalocyanine pigment in the toner, and C denotes the content ratio (mass %) of the Mn containing hematite in the toner.

Magnetic black toner for electrophotography having Mn-containing hematite compound and magnetic two-component developer for electrophotography containing the same

The present invention provides an image forming method for obtaining excellent color fixed images with a smaller amount of light energy. This image forming method includes the steps of: forming a toner layer of a color toner containing at least a binder resin, a coloring agent, and an infrared absorbent, on a recording medium; and fixing the toner layer by flashlight emission, where the relationship among the PAS level S of the color toner that is obtained by integrating an infrared PAS spectrum obtained through PAS (photoacoustic spectroscopy) analysis in the range of 800 nm to 2000 nm, the melt viscosity &#x3c1; of the color toner at a reference temperature, and the energy E of the flashlight, is expressed by the following relational expression:1000&#x2266;&#x3c1;/&#x2266;5500.

Image forming method

In an imaging color toner employing a photofixing system, a binder resin, which contains, as a principal component, a polyester resin obtained by mixing a first polyester resin having a softening point Tsp of not lower than 120&#xb0; C. and lower than 170&#xb0; C. with a second polyester resin having a softening point Tsp of not lower than 80&#xb0; C. and lower than 110&#xb0; C. in a weight ratio of 80:20 to 20:80, is used. The color toner is used in an electrophotographic process and other imaging processes.

Imaging color toner, color image forming method and color image forming apparatus

An image-forming process for forming a full-color image including: forming a full-color toner image by supplying at least a cyan toner, a magenta toner, and a yellow toner onto a recording medium; and fixing the toner image on the recording medium by flash fusing, wherein each of the cyan toner, the magenta toner and the yellow toner contains an infrared absorbent, the cyan toner is supplied so that out of the cyan toner, the magenta toner and the yellow toner, the cyan toner is positioned in the uppermost layer in areas of the toner image where cyan toner is present, and the flash fusing is performed by a delayed light emission process wherein a plurality of flash lamps emit lights at a time interval.

Image-forming process and image-forming apparatus using flash fusing

A toner for electrophotography fulfilling both the fixability and the void resistance at high level, and forms a high-quality image. The toner for electrophotography contains: a binder resin; and a wax component which contains: a first wax having an endothermic peak in a temperature region of 60 to 90&#xb0; C., the endothermic peak occurring in the temperature-rising stage of a DSC curve determined by a differential scanning calorimeter, and having a molecular weight distribution (weight-average molecular weight (Mw)/number-average molecular weight (Mn)) of 1.5 or less, and substantially not containing a component having 500 Mw or less; and at least any of a second wax having an endothermic peak in a temperature region of 100 to 150&#xb0; C. and the molecular weight distribution of 5 to 20; and a third wax having an endothermic peak in a temperature region of 150 to 170&#xb0; C. and the molecular weight distribution of 1.1 or more.

Toner for electrophotography and developer for electrophotography using the same, process cartridge, apparatus for forming image, and method for forming image

This invention provides: a color toner to be fixed on a recording medium with a flash light comprising a binder resin, an infrared ray absorbent and a coloring agent for mainly developing a yellow color, wherein the coloring agent is C.I. Pigment Yellow 180 or C.I. Pigment Yellow 185; a color toner to be fixed on a recording medium with a flash light comprising a binder resin, an infrared ray absorbent and a coloring agent for mainly developing a magenta color, wherein the coloring agent is C.I. Pigment Violet 19; and a color toner to be fixed on a recording medium with a flash light comprising a binder resin, an infrared ray absorbent and a coloring agent for mainly developing a cyan color, wherein the coloring agent is C.I. Pigment Blue 15. Also disclosed are a color toner set comprising these color toners and an image forming apparatus employing at least one of the color toners or the color toner set.

Color toner and image forming apparatus using the color toner

A developing device for electrophotographic image has a developing mechanism having a developer carrier for carrying a developer along a preset circulating route including a developing area and a developer restricting element for restricting the developer on the developer carrier, and a developer supply mechanism having a storing unit. The storing unit is filled with a start-up developer in the vicinity of the developer carrier and a replenishing developer remoter than the start-up developer from the developer carrier. The start-up developer and the replenishing developer have different grain sizes or grain size distributions. Further, a developing method for electrophotograhic image has the steps of using the start-up developer at an initial state of use of the developing mechanism, and using the replenishing developer differed in grain size or grain size distribution from the start-up developer after an end of the initial state of use of the developing mechanism.

Developing method and developing device for electrophotographic image, and printing device using the developing device

In a method for forming a multicolored toner image in accordance with an electrophotographic process, the addition amount of external additives to a non-added toner is 1.5 to 10.0 parts by weight per 100 parts by weight of the non-added toner in each developing step, the aggregation degree of the toner is within the range of 30 to 80%, and the change ratio of the aggregation degree satisfies the relation:0.8&#x2266;(initial aggregation degree/aggregation degree after no-load revolution of developing portion for 20 hours)&#x2266;1.2. According to this method, it becomes possible to form a high-quality color image while a toner always keeps a stable degree of aggregation and a charge amount.

Color image formation method

The 'sequential developments and one-time fixing' method of the present invention specifies that a toner having the greatest PAS strength value should be placed on the top of a lamination of toner layers, which provides efficient radiant energy absorption by the whole lamination of the toner layers, allows efficient heat transmission from the top layer to lower layers, and provides satisfactory color image fixing at relatively low flashing light irradiation energy.

Image fixing method

A toner has a surface to which a titanium black fine particle adheres, the titanium fine particle having a property of being changed in color from black to white by flash-light.

Toner and an image formation method

It is a toner for optical fixing which contains a binder resin, a colorant, and an infrared light absorbent, and the infrared light absorbent has a coloring opacity of 20 or less, and of phthalocyanine compound and/or naphthalocyanine compound.

Toner for optical fixing, manufacturing method therefor and image formation apparatus using it

In a color toner for forming an image, comprising at least a binder resin and a colorant, light-absorbing fine composite particles comprising core particles and at least two coating layers having different refractive indexes laminated on the surface of the core particles or other IR-absorbing compounds such as an azulene compound having a specific structure are used as an infrared absorbing compound. The color toner is used in an electrophotographic color image forming apparatus using a photofixing system for fixing a toner image.

Image forming color toner, color image forming method and color image forming apparatus

An image formation method for forming an image is proposed, which uses an image formation apparatus capable of performing (1) multi-color image formation and printing by superimposing toner images with different colors by use of a plurality of color toners with different colors, including at least a black toner, and (2) monochrome image formation and printing, using only a black toner, with a maximum transferable amount of each color toner onto the image being in a range of 4&times;10 kg/m to 8&times;10 kg/m , wherein an image glossiness (GKC) obtained by the black toner in the maximum transferable amount thereof at the multi-color image printing, an image glossiness (GCC) obtained by each of the color toners other than the black toner in the maximum transferable amount thereof at the multi-color image printing, and an image glossiness (GKM) obtained by the black toner in the maximum transferable amount thereof at the monochrome image printing satisfy a particular relationship as described in the specification. In addition, the above toners and a printed matter prepared by this image formation method are proposed.

Image formation method, electrophotographic toners, and printed matter

A color image forming apparatus forms a color image on a recording medium by using a toner including a binding resin, a coloring agent and infrared ray absorbent, and a light source for causing the toner to melt. The light source has a plurality of light emission peaks having wavelengths of &lgr; , . . . , &lgr;n in a range of 500 nm through 3000 nm. Setting is made such that the following relationship is satisfied: &verbar;&lgr; <100 nm, and, also, &verbar;&lgr; &verbar;<100 nm, where &Lgr; and &Lgr; denote absorption peak wavelengths of said infrared ray absorbent.

Color image forming apparatus and color toner

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Kawasaki, Japan

Yoshimichi Katagiri