Kao Corporation

Nippon Paint Compnay, Ltd.

Shinji Moriyama

Yoshihiro Fukushima

Yutaka Kanamaru

Hidenori Tachi

Kuniyasu Kawabe

Masayuki Maruta

Takashi Kubo

Katsutoshi Aoki

Ikuo Takahashi

Takashi Sakurai

Yoshiki Yoshimura

Eiji Shirai

Yasunori Inagaki

Yukiya Sato

Yoshihiro Ueno

Hisakazu Tajima

Tetsuhiro Semura

Masahiro Umehara

Takeshi Atsugi

Yasuyuki Tamane

Tutomu Akashi

Kazuhiko Sugawara

A process for preparing a mixed color toner obtained by mixing two or more kinds of color toners of which each color is different, including the following steps (1) and (2):

Process for preparing mixed color toner

A method of forming fixed images, including the step of applying a two-component developer containing a carrier and a toner containing a wax and a resin binder containing a crystalline polyester to a two-component development device with a linear speed of from 500 to 5,000 mm/sec, to develop the toner, wherein the crystalline polyester is contained in an amount of from 3 to 40% by weight and the wax in an amount of from 2.5 to 10% by weight, of the toner, and wherein the two-component development device comprises at least three magnet rollers which are arranged closely to each other along the perimeter of a photoconductor, wherein one magnet roller arranged on the uppermost side in the rotational direction of the photoconductor rotates in a direction opposite to the rotational direction of the photoconductor at the point therebetween, and the other magnet rollers rotate in the same direction as the photoconductor at the point therebetween. The method of forming fixed images according to the present invention forms excellent fixed images by, for example, development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method, or the like.

Method of forming fixed images

The present invention relates to a crystalline polyester for toner, obtained by a process comprising the step of polymerizing raw material monomers in the presence of a wax, wherein the crystalline polyester has a number-average molecular weight of from 3000 to 10000 and a weight-average molecular weight of from 150000 to 8000000. The toner containing the crystalline polyester of the present invention can be used, for example, for developing electrostatic latent images formed in electrophotography, electrostatic recording method, electrostatic printing method, and the like.

Crystalline polyester for toner

A toner comprising a resin binder and a colorant comprising a composite oxide of two or more metals, wherein the composite oxide has a BET specific surface area of 0.5 to 7 m/g and a saturation magnetization of from 1 to 40 Am/kg; and a two-component developer comprising the above toner and a carrier having a saturation magnetization of from 40 to 100 Am/kg. The toner can be used for the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.

Toner

A toner comprising a resin binder, a black colorant comprising a composite oxide of two or more metals, and a charge control agent comprising a quaternary ammonium salt. The toner is suitably used for the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.

A combination of powder coatings usable in a powder coating method for forming a coating film having visually homogeneous hue by mixing two or more powder coatings of which each color is different. In the combination of powder coatings, each of differences in triboelectric charges of two or more powder coatings is 5.0 &#x3bc;C/g or less. The coating method usable herein includes the step of applying onto a substrate to be coated two or more powder coatings of which each color is different, in which the triboelectric charges are controlled in the above given ranges.

Powder coating

A toner for development of electrostatic latent images, comprising a resin binder comprising a resin having a softening point of from 120&#xb0; to 170&#xb0; C., a glass transition point of from 58&#xb0; to 75&#xb0; C., and a percentage of chloroform-insoluble component of from 5 to 50% by weight; and a resin having a softening point of 90&#xb0; C. or more and less than 120&#xb0; C., a glass transition point of from 58&#xb0; to 75&#xb0; C., and a percentage of chloroform-insoluble component of less than 5% by weight; and at least one low-melting point wax having a melting point of from 60&#xb0; to 90&#xb0; C. The toner for development of electrostatic latent images has low lowest fixing temperature and is excellent in the offset resistance, the blocking resistance and the durability.

Toner for development of electrostatic latent images

A positively chargeable toner for two-component development comprising a resin binder; a colorant; a releasing agent comprising a wax having a melting point of 50&deg; to 120&deg; C.; and an external additive comprising a positively chargeable silica, the positively chargeable silica having an absolute deviation of an error of 0.1 or less, against an approximate straight line showing an adhesion state of silicon atoms to carbon atoms, and a free ratio of 5% or less, wherein the positively chargeable toner is usable together with a ferrite carrier having a saturation magnetization of from 40 to 100 Am /kg. This positively chargeable toner is used for development of an electrostatic latent image formed in electrophotography, electrostatic recording method, electrostatic printing method, or the like.

Positively chargeable toner for two-component development

Printing method, printer, printed object, and optical disk

Optical disc, process for producing the optical disc and its

The binder resin for producing a toner includes the following three resins (A) to (C): resin (A) having a softening point of 120.degree. C. or more and 170.degree. C. or less, a glass transition temperature of 58.degree. C. or more and less than 75.degree. C., and a weight percentage of components insoluble to chloroform at 25.degree. C. of 5% by weight or more and 50% by weight or less; resin (B) having a softening point of 90.degree. C. or more and 120.degree. C. or less, a glass transition temperature of 58.degree. C. or more and less than 75.degree. C., and a weight percentage of components insoluble to chloroform at 25.degree. C. of less than 5% by weight; and resin (C) having a softening point of 80.degree. C. or more and less than 110.degree. C., a glass transition temperature of 45.degree. C. or more and less than 58.degree. C., and a weight percentage of components insoluble to chloroform at 25.degree. C. of less than 5% by weight.

Binder resin and toner for electrostatic development containing the same

The toner for color electrophotography employing simultaneously fixing of various color toners, includes at least a coloring agent and a binder resin, wherein inorganic fine particles are internally added to the toner to have viscoelastic properties approximated to a level of other toners with different colors to be simultaneously fixed together therewith. The method for heat and pressure fixing a transferred image formed by toners of two or more colors on a recording medium using a heat roller, includes the step of fixing the transferred image formed by the above toner for color electrophotography together with black toner.

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Wakayama, Japan

Shinji Moriyama