Konica Minolta Business Technologies, Inc.

Konica Corporation

Kaori Soeda

Meizo Shirose

Eiichi Yoshida

Masahiko Nakamura

Tomoko Mine

Kenichi Onaka

Yoshiaki Kobayashi

Hiroshi Yamazaki

Naohiro Hirose

Shinya Obara

Masahiro Anno

Tatsuya Nagase

Ken Ohmura

Asao Matsushima

Shiro Hirano

Miyuki Murakami

Tatsuya Fujisaki

Yohei Ohno

Kazuya Isobe

Hiroyuki Yamada

Koji Washio

Hiroyuki Yasukawa

Shigenori Kouno

Yoshiki Nishimori

Yoshiyasu Matsumoto

Ryuji Kitani

Natsuko Kusaka

Yasuko Yamauchi

Youhei Ohno

Hidemasa Sawada

Kazuhisa Horiuch

Provided is a full color image forming method wherein high color reproducibility especially on a blue system and a green system can be obtained and an excellent gradation property can be obtained in a full color image to be obtained. The full color image forming method for forming a full color image by using at least yellow toner, magenta toner, and two kinds of cyan toners (1, 2) is characterized in that a toner image formed by the cyan toner (1) alone has the value of the maximum color saturation (C*) of not less than 50 and the value of lightness (L*) in a color space represented by an L*a*b* colorimetric system of not less than 30 and not more than 52, and that a toner image formed by the cyan toner (2) alone has the value of the maximum color saturation (C*) of not less than 50 and the value of the lightness (L*) in the color space represented by the L*a*b* colorimetric system of not less than 58 and not more than 75.

Full color image forming method using two cyan toners

An orange toner for developing electrostatic charge images includes a binder resin; and a colorant including a first color material and a second color material; wherein the first color material has a hue angle of &#x2212;20&#xb0; to 80&#xb0; in a L*a*b* color system, the second color material includes C.I. Solvent Orange 63, and the second color material has a content of 0.05 to 0.2 parts by mass to 100 parts by mass of the binder resin.

Orange toner for developing electrostatic charge images

Disclosed is an image forming apparatus including a color converter for converting cyan, magenta and yellow components of a first image signal to equivalent neutral density, calculating a first gray component from cyan, magenta and yellow components of equivalent neutral density, subtracting the first gray component from each of the cyan, magenta and yellow components of equivalent neutral density, subjecting each of the cyan, magenta and yellow components of equivalent neutral density from which the first gray component is subtracted to an inverse conversion of the equivalent neutral density conversion, and outputting a second image signal comprising cyan, magenta and yellow components which are obtained by carrying out the inverse conversion to the cyan, magenta and yellow components of equivalent neutral density from which the first gray component is subtracted, the first black component and the first gray component; an image forming section for forming an image on a paper based on the second image signal by using cyan, magenta, yellow, black and gray toners; and a controller for controlling the color converter and the image forming section.

Image forming apparatus and image forming method which enhance graininess and also reduce a total toner amount without deteriorating image quality in image formation using toner of high chroma

Disclosed are a toner for developing an electrostatic image, a full color toner kit and an image formation method, the toner containing at least a resin and a colorant, wherein the colorant comprises a quinacridone pigment having a number average primary particle size of from 30 to 150 nm and having a ratio of a major axis direction length to a minor axis direction length of from 1.0 to 2.0 and Pigment Red 238.

Toner for developing electrostatic image, full color toner kit, and image formation method

Provided is a method for forming an image with a set of electrostatic charge image developing toners using a digital electrophotographic method, provided that the set of electrostatic charge image developing toners comprises a black toner and a light gray toner, the method comprising the steps of: forming an electrostatic latent image on an image support; developing the electrostatic latent image with the black toner to form a black toner image; developing the electrostatic latent image with the light gray toner to form a light gray toner image; and fixing the black toner image and the light gray toner image, wherein the black toner and the light gray toner each independently contains a wax having an endothermic peak in the range of 60 to 105&#xb0; C.; and the light gray toner has a transmittance in the range of 40 to 90%.

Image forming method

A set of toners comprising a yellow toner, a magenta toner, a cyan toner and a black toner for forming a full color image with an electrophotographic method, wherein the yellow toner comprises toner particles containing at least one pigment selected from the group consisting of C.I. Pigment Yellow 74, C.I. Pigment Yellow 139, C.I. Pigment Yellow 155, C.I. Pigment Yellow 180 and C.I. Pigment Yellow 185; the magenta toner comprises toner particles containing a dye represented by Formula (X-1) and a metal compound represented by Formula (1); and the cyan toner comprises toner particles containing a silicon phthalocyanine represented by Formula (2): 

Electrophotographic toner

Provided is a set of toners comprising a yellow toner, a magenta toner, a cyan toner and a black toner for forming a full color image with an electrophotographic method, wherein the yellow toner comprises toner particles containing at east one pigment selected from the group consisting of C. I. Pigment Yellow 74, C. I. Pigment Yellow 139, C. I. Pigment Yellow 180, C. I. Pigment Yellow 185 and C. I. Pigment Yellow 155; the magenta toner comprises toner particles containing a rhodamine based dye represented at least by Formula (1) and Formula (2), and the cyan toner comprises toner particles containing a phthalocyanine based dye represented by Formula (5): 

Electrophotographic toner set

An electrophotographic image forming method is disclosed. In the method electrostatic latent image is developed by a non-magnetic single-component developing system, in which a non-magnetic single-component developer is conveyed by a developer carrying member, the developer carrying member is contacted with a developer layer regulation member for regulating an amount of the developer at the surface of the developer carrying member, and a binder resin of the developer comprises a vinyl polymer having an acid value of from about 5 to about 30 mgKOH/g and a ratio of hydroxyl group value/acid values from about 0.3 to about 0.8.

An electrostatic image developing toner is disclosed, comprising a resin and a colorant, wherein the toner contains at least one iminocarboxylic acid or its salt in an amount of from 26 to 388 ppm by mass.

Toner for use in electrostatic image development

A method of decolorizing a colored effluent comprising (i) a colored substance; and (ii) a polyvalent carboxylic acid or a polyvalent aminocarboxylic acid, the method including the steps of: (a) controlling a hydrogen ion exponent (pH) of the colored effluent to be in a range in which two or more carboxylic acid groups in the polyvalent carboxylic acid or the polyvalent aminocarboxylic acid does not dissociate; (b) adding an inorganic metal salt to the colored effluent so as to allow the inorganic metal salt to react with the colored substance to form a precipitation in the colored effluent, and (c) eliminating the precipitation from the colored effluent.

Decolorization method of colored effluent

Disclosed is an image forming method comprising developing a latent electrostatic image formed on the surface of a latent electrostatic image bearing body by a developer borne and conveyed by a developer bearing body which is brought into contact with a developer layer control member to control an amount of the developer on the surface of the developer bearing body through a nonmagnetic single-component development system, wherein an acid value (SAV) of the surface of the developer and a total acid value (TAV) of the developer meet the following requirements:1&#x3c;SAV/TAV&#x2266;5 and 5&#x2266;TAV&#x2266;25,and a ratio of a mass average particle size (d50, &#x3bc;m) of the developer to a surface roughness (Ra, &#x3bc;m), d50/Ra being in a range of 0.5 to 3.0 and an average spacing (Sm) between protruding peaks of the developer bearing body being in a range of 20 to 200 &#x3bc;m.

A toner comprising: (i) toner particles, each toner particle comprising a binder resin and a colorant; and (ii) an oxymonocarboxylic acid or a salt thereof, wherein a total content of the oxymonocarboxylic acid or the salt thereof in the toner is 10 to 173 ppm based on the total weight of the toner.

Electrostatic image developing toner

Provided is an electrostatic charge image developing toner usable for downsized color image forming apparatus capable of rapid print preparation with neither an influence on production cost nor use of a specific material as the toner constituent material. Also disclosed is an electrostatic charge image developing toner possessing at least a resin and a colorant, wherein the electrostatic charge image developing toner contains 12-984 ppm of a polyvalent organic acid or a salt thereof.

Electrostatic charge image developing toner

The invention relates to a static latent image developing toner comprising toner particles, each of the toner particles comprising a toner intermediate particle having inorganic oxide particles on the surface, wherein a surface existence density of the inorganic oxide particle having a feret's diameter of 110 nm to 160 nm on the toner intermediate particle is 5 to 50 per &#x3bc;m, and relates to a developer comprising the toner and an image forming method utilizing the toner.

Static latent image developing toner, developer and image forming method

A toner for forming a color image comprises chromatic toners and a black toner is disclosed. Each of the toners is produced by polymerization of a polymerizable monomer in an aqueous medium, the difference of re-dispersion electro-conductivity of each of the toners is within the range of from 0.8 to 12 &mgr;s/cm, the number of free colorant particles on the black toner surface is less than 9 per 500 toner particles, and a light absorbance at 500 nm of a black toner dispersion is nor more than 0.08.

Growing community of inventors

Tokyo, Japan

Kaori Soeda