Konica Minolta, Inc.

Konica Minolta Business Technologies, Inc.

Junya Onishi

Shiro Hirano

Aya Shirai

Tatsuya Fujisaki

Noboru Ueda

Naoya Tonegawa

Masahiro Anno

Masahiko Nakamura

Tsuyoshi Uchida

Kenichi Onaka

Kouji Sugama

Tatsuya Nagase

Takaki Kawamura

Shingo Fujimoto

Takao Yamanouchi

Anju Hori

Masaaki Kondo

Shinya Obara

Yasuko Uchino

Junya Ueda

Ikuko Sakurada

Hirofumi Koga

Natsuko Fujisaki

Kenshi Miyajima

Hidehito Haruki

Junichi Furukawa

Ami Motohashi

Hiroshi Nagasawa

Satoshi Uchino

Kaori Matsushima

Yoshiyasu Matsumoto

Taiki Amemiya

Kouji Sekiguchi

Kouichi Sugama

Kazumi Oura

Kentarou Mogi

Kaori Fujino

Provided is an electrostatic charge image developing toner including toner base particles containing a binder resin an a mold release agent, wherein a molecular weight corresponding to a main peak top of a molecular weight distribution curve of constituent components of the electrostatic charge image developing toner obtained by gel permeation chromatography is 15,000 or more; and in comparison of an area ratio of each peak in the molecular weight distribution curve, the binder resin contains an amorphous material of a low molecular weight component having a weight average molecular weight of 300 or more and less than 1000 in the area ratio of 10 to 20% with respect to the total amount of the binder resin.

Electrostatic charge image developing toner, production method of same, and electrophotographic image forming method

Provided is an electrostatic image developing toner including: toner mother particles containing a binder resin and a releasing agent; and an external additive, wherein the binder resin contains a crystalline resin, and the electrostatic image developing toner satisfies the following formulas (1) and (2),tan &#x3b4;&#x3c;tan &#x3b4;&#x2003;&#x2003;Formula (1):0.0005&#x2264;tan &#x3b4;&#x2212;tan &#x3b4;,&#x2003;&#x2003;Formula (2):wherein: tan &#x3b4;is a peak top value of a loss tangent when the loss tangent is measured from 25&#xb0; C. to 100&#xb0; C. at a frequency of 1 Hz and a heating rate of 6&#xb0; C./min; and tan &#x3b4;is a peak top value of a loss tangent when the loss tangent is measured from 25&#xb0; C. to 100&#xb0; C. at a frequency of 1 Hz and a heating rate of 3&#xb0; C./min.

Electrostatic image developing toner

In an image forming method according to the present invention, an image is formed by removing residual charge from the image on an image recording medium. The image forming method includes formation of an image for forming a toner image by fixing a toner on the image recording medium and application of voltage from a voltage applier, the voltage having a polarity reverse to a polarity of a surface potential of the toner image. The toner includes toner base particles and an external additive. The toner base particles include a crystalline polyester resin.

Image forming method

Provided is a toner for developing electrostatic images containing a toner particle. The toner particle contains a binder resin and a release agent. The binder resin contains a vinyl resin component and a crystalline polyester resin component. The vinyl resin component has a structural unit derived from an alkyl (meth)acrylate monomer represented by Formula (1):HC&#x2550;CR&#x2014;COOR&#x2003;&#x2003;Formula (1):In Formula (1), Rrepresents a hydrogen atom or a methyl group, and Rrepresents an alkyl group having 8 to 22 carbon atoms. The crystalline polyester resin component satisfies Formula (2):5&#x2264;|C&#x2212;C|&#x2264;12 &#x2003;&#x2003;Formula (2):In Formula (2), Crepresents the number of carbon atoms of the main chain of a structural unit derived from a polyhydric alcohol and Crepresents the number of carbon atoms of the main chain of a structural unit derived from a polyvalent carboxylic acid.

Toner for developing electrostatic images

A process for producing a toner of the present invention includes: a first step of heating a dispersion containing an aqueous medium and a binder resin containing a crystalline resin to a temperature higher than or equal to a melting point of the crystalline resin; and a second step of maintaining the dispersion at temperature T (&#xb0; C.) for 30 minutes or longer in a state where a pH of the dispersion is maintained at 5.5 or higher and 9.0 or lower, in which the temperature T satisfies the following expression, Rc&#x2212;25&#x2264;T&#x2264;Rc&#x2212;5, where the Rc represents a recrystallization temperature (&#xb0; C.) of the crystalline resin.

Process for producing a toner

The present invention relates to a toner for electrostatic charge image development, including toner base particles containing a binder resin containing as a main component a vinyl resin having a constitutional unit derived from a monomer having an acid group, and aluminum, wherein a concentration of the aluminum in the toner base particles, as measured by radio inductively coupled plasma emission spectral analysis, is from 900 to 2,200 ppm. According to the present invention, there is provided a means for improving the environmental stability of electrification, and the glossiness and the image density of the image to be formed in a good balance while maintaining sufficient low temperature fixability in a toner for electrostatic charge image development.

Toner for electrostatic charge image development

An image forming method forms a color toner image and a white toner image using an image forming apparatus having a plurality of developing machines. The color toner image is formed using a color developer containing a first carrier and at least one color toner selected from a yellow toner, a magenta toner, and a cyan toner. The white toner image is formed using a white developer containing a second carrier and a white toner containing at least titanium oxide as a pigment. Formula (1):Iw&#x3c;Ic&#x2003;&#x2003;(1)is satisfied. Ic (&#x3bc;A) is a dynamic current value of the first carrier at 100 V and Iw (&#x3bc;A) is a dynamic current value of the second carrier at 100 V.

Image forming method, electrostatic charge image developer set, and image forming apparatus

The production process of the present invention includes: a first step of heating a dispersion containing an aqueous medium and a binder resin containing a crystalline resin to a temperature higher than or equal to the melting point of the crystalline resin in a step of aggregating and fusing a fine particle of the binder resin containing the crystalline resin to produce a toner base particle; a second step of cooling the dispersion having been heated in the first step and having a temperature higher than the recrystallization temperature Rc of the crystalline resin to a temperature lower than Rc at a temperature-lowering rate of 1&#xb0; C./min or higher; and a third step of maintaining the dispersion having been cooled in the second step at a temperature higher than or equal to Rc&#x2212;25&#xb0; C. and lower than or equal to Rc&#x2212;5&#xb0; C. for 30 minutes or longer.

Provided is a toner for developing electrostatic images containing toner particles. The toner particles contain a crystalline resin and an amorphous resin. The amorphous resin contains an amorphous vinyl resin component containing a polymer of monomers having a structure represented by formula (1). The content of a structural unit derived from the monomers in the toner particles is within a range of 2.4 to 13.5 mass %.HC&#x2550;CR&#x2014;COOR&#x2003;&#x2003;(1)In formula (1), Rrepresents a hydrogen atom or a methyl group and Rrepresents a branched alkyl group having a carbon number of 8 or more.

Toner for developing electrostatic images and method of producing toner

A toner for developing electrostatic latent images contains a particulate toner which at least includes a colorant, a binder resin, a mold release agent, and a crystalline polyester resin. The binder resin contains a styrene-acrylic resin. The toner has a storage modulus G', a difference (X) between the maximum value and the minimum value of the storage modulus G&#x2032;, and a difference (Y) between the maximum value and the minimum value of a loss modulus G&#x2033; within the range of 140 to 180&#xb0; C. satisfying relationships expressed by Conditional expressions (1) 1.0&#xd7;10&#x2266;G&#x2032;&#x2266;1.0&#xd7;10, (2) 0&#x2266;X&#x2266;3.0&#xd7;10, and (3) 0&#x2266;Y&#x2266;6.0&#xd7;10.

Toner for developing electrostatic latent images

The present invention relates to an image forming method using a yellow toner, a magenta toner, and a cyan toner, in which the yellow toner, the magenta toner, and the cyan toner respectively contain toner base particles containing a binder resin containing an amorphous polyester resin as a main component and a crystalline resin, aluminum, and a colorant, and the concentration of aluminum in the toner base particles of the yellow toner measured by high-frequency inductively coupled plasma emission spectral analysis satisfies a specific relation. According to the present invention, an image forming method and a toner set which can improve the thin paper separation property while maintaining favorable low temperature fixability are provided.

Image forming method and toner set

An electrostatic image developing toner includes toner particles that contain coloring particles containing a binder resin, a coloring agent and a releasing agent. The binder resin includes an amorphous resin and a crystalline polyester resin. The toner satisfies Relations (1) and (2). &#x394;H1 is the amount of heat absorption based on a melting peak of the crystalline polyester resin in a first heating step. &#x394;H2 is the amount of heat absorption based on a melting peak of the crystalline polyester resin in a second heating step. &#x394;H0 is the value of the amount of heat absorption based on a melting peak of the crystalline polyester resin in the second heating step, multiplied by the ratio of the crystalline polyester introduced in the electrostatic image developing toner.0.43&#x3c;&#x394;1/&#x394;0&#x3c;0.95&#x2003;&#x2003;Relation (1):0.45&#x3c;&#x394;2/&#x394;1&#x3c;1.20&#x2003;&#x2003;Relation (2):

The toner according to the present invention comprises a matrix phase composed of a vinyl resin, and domain phases composed of a non-crystalline polyester resin dispersed in the matrix phase, and a number-average domain diameter of the domain phases composed of the non-crystalline polyester resin is 30 to 150 nm. The toner satisfies relation represented by a specific requirement of the total area of the domain phases present in a surface layer area of the toner particle, and the total area of the domain phases present in areas other than the surface layer area, in a given cross-section of the toner particle.

Toner for developing electrostatic latent image and process for producing the same

Disclosed is a toner for electrostatic image development having excellent low-temperature fixability and high-temperature off-set resistance, attaining good image density, and having excellent homogeneity in image density. The toner comprises toner particles containing a binder resin which contains an amorphous resin (A) and an amorphous polyester resin (B) different from the resin (A) and a colorant, wherein the toner particles have a domain-matrix structure having the resin (B) as a domain phase dispersed in a matrix phase comprising the resin (A), and in a cross-sectional image of the toner particles, the number average domain diameter of the domain phase of the resin (B) having a domain diameter of 100 nm or more is 100 to 200 nm and an area ratio of the domain phase having a domain diameter of 500 nm or more relative to the total area of the domain phase is 0 to 10%.

Toner for electrostatic image development

The invention provides an image formation method, a toner set, and a white toner, by which a masking function of an image layer formed by a white toner on a recording medium can be developed efficiently, and low temperature fixability can be improved. An image formation method for fixing an image forming layer (A) to be formed using a white toner, and an image forming layer (B) to be formed adjacent to the image forming layer (A) using a toner different from the white toner on a recording medium; wherein the following relational expressions (1) and (2) are satisfied:1.000&#x3c;&#x3c;1.300&#x2003;&#x2003; (1);and1.000&#x3c;&#x3c;1.060&#x2003;&#x2003;(2).

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Hachioji, Japan

Junya Onishi