Ricoh Company, Ltd.

Rintaro Takahashi

Hiroshi Yamashita

Tsuyoshi Sugimoto

Daisuke Asahina

Masana Shiba

Shingo Sakashita

Satoyuki Sekiguchi

Daisuke Inoue

Tomoki Murayama

Yukari Fukuda

Ryota Inoue

Yoshitaka Yamauchi

Tatsuya Morita

Yoshitsugu Kimura

Shinya Nakayama

Masaki Watanabe

Kazumi Suzuki

Naohiro Watanabe

Junichi Awamura

Masahide Yamada

Taichi Nemoto

Azumi Miyaake

Atsushi Yamamoto

Takamasa Hase

Satoshi Kojima

Akiyoshi Sabu

Takahiro Honda

Takayuki Itoh

Suzuka Amemori

Susumu Chiba

Tatsuru Moritani

Akio Takei

Hiroshi Endoh

Daisuke Misawa

Ayumi Satoh

Chihiro Kikuchi

Saki Konno

Kousuke Nagata

A toner includes a binder resin; a release agent; and two or more inorganic fine particles as external additives. At least one of the inorganic fine particles is silica. When an ultrasonic oscillation is applied to a dispersion including the toner and a dispersant and a rate of the silica releasing from the toner is 20% based on total silica, an application energy of the ultrasonic oscillation is from 8 to 14 kJ, and from 70 to 130 kJ when the rate of the silica releasing from the toner is 50%.

Toner, developer, toner housing unit and image forming apparatus

A toner including a binder resin, wherein a toner extract obtained by drying an extraction liquid obtained through Soxhlet extraction of the toner with tetrahydrofuran (THF) has glass transition temperature Tg in a range of from 35&#xb0; C. through 55&#xb0; C., and a moisture-content change rate of the toner extract before and after leaving the toner extract to stand for 3 days in an environment of 40&#xb0; C. and 70% RH is 0.5% or less, and wherein a specific-surface-area change rate of the toner before and after leaving the toner to stand for 3 days in an environment of 40&#xb0; C. and 70% RH is in a range of from 15% through 50%.

Toner, toner stored unit, and image forming apparatus

A toner comprising a binder resin and a release agent, wherein the toner has a difference of 30 or less between a maximum value and a minimum value among peak intensities in a range of Molecular weight M&#xb1;300 where Molecular weight M is a molecular weight selected from a range of from 300 through 5,000 in a molecular weight distribution of tetrahydrofuran (THF)-soluble components in the toner as measured by gel permeation chromatography (GPC), and wherein the peak intensities are defined as relative values assuming a maximum peak value in molecular weights of 20,000 or less is 100, in a molecular weight distribution curve taking an intensity as a vertical axis and a molecular weight as a horizontal axis as measured by GPC.

A toner including a binder resin and a release agent, wherein the toner has a component soluble in a 50% by mass aqueous methanol solution in an amount of 0.10% by mass to 0.60% by mass, and wherein the toner has a flowing-out beginning temperature (Tfb) of 55.0&#xb0; C. to 100.0&#xb0; C. as determined by a flowtester method.

Toner, image forming apparatus, and process cartridge

A toner, including: a binder resin; and a colorant, wherein the toner has a storage modulus of 1.0&#xd7;10Pa or more at 50&#xb0; C., a loss modulus of 8.0&#xd7;10Pa to 2.0&#xd7;10Pa at 80&#xb0; C., and a loss modulus of 2.0&#xd7;10Pa to 1.0&#xd7;10Pa at 160&#xb0; C.

Toner, developer, and color toner set

A toner including a crystalline resin wherein the crystalline resin contains a crystalline resin having a urethane bond, a urea bond or both thereof, and wherein the crystalline resin has an average crystallite diameter of 20 nm to 70 nm.

Toner, developer, and image forming apparatus

To provide an electrophotographic toner, which contains a crystalline resin, a non-crystalline resin, a colorant, and a releasing agent, wherein the toner has a storage elastic modulus of 5.0&#xd7;10Pa to 5.0&#xd7;10Pa at 80&#xb0; C., and a storage elastic modulus of 2.0&#xd7;10Pa to 2.0&#xd7;10Pa at 140&#xb0; C., and wherein the toner has a ratio (C)/((C)+(A)) of 0.10 or greater, where (C) is an integrated intensity of a diffraction spectrum derived from a crystalline structure, (A) is an integrated intensity of a diffraction spectrum derived from a non-crystalline structure, and the diffraction spectrum is a diffraction spectrum of the toner as measured by an X-ray diffraction spectrometer.

Electrophotographic toner, two-component developer containing toner, and image forming apparatus

A toner, including: a crystalline resin; a non-crystalline resin; and a colorant, wherein the toner has a sea-island structure which includes a sea containing the crystalline resin and an island containing the non-crystalline resin and the colorant, wherein the island is 1.0 &#x3bc;m or less in domain diameter, and wherein the toner is 1.7&#xd7;10Pa or less in storage elastic modulus at 160&#xb0; C.

Toner, method for producing the toner, two-component developer, and image forming apparatus

To provide a toner, which contains a colorant, a binder resin, and a releasing agent, wherein the toner satisfies the following (a) to (c): (a) the toner contains at least a polyester resin as the binder resin; (b) the toner has Tg1st of 25&#xb0; C. to 50&#xb0; C.; and (c) the toner has a TMA compressive deformation rate (TMA %) of 10% or lower at 50&#xb0; C. under a condition having relative humidity of 70%, wherein the Tg1st is glass transition temperature of the toner for first heating, as the toner is measured by a DSC system (a differential scanning calorimeter).

Toner for forming electrostatic image, developer, process cartridge, and image forming apparatus

An image forming apparatus, including: photoconductor; charging unit; exposing unit; developing unit containing toner; transfer unit; and fixing unit, wherein the toner includes external additive and base particles containing binder resin, colorant, and release agent, the toner has melt viscosity at 100&#xb0; C. of 500 Pa&#xb7;s to 8,000 Pa&#xb7;s and the release agent has melt viscosity at 100&#xb0; C. of 20 mPa&#xb7;s to 30 mPa&#xb7;s, the fixing unit includes fixing member that has roller or belt shape and contacts toner image transferred onto recording medium, and the fixing member includes release layer on surface thereof that is to be brought into contact with the toner image transferred onto the recording medium, and wherein the release layer satisfies the following expressions:45&#x2266;&#x3b8;1&#x2266;60, and10&#x2266;&#x3b8;1&#x2212;&#x3b8;2,

Image forming apparatus

A toner containing colorant, releasing agent, and binder resin containing crystalline polyester resin, and non-crystalline polyester resin containing urethane bond, urea bond, or both, the non-crystalline polyester resin containing first and second non-crystalline polyester resins, both containing urethane bond, or urea bond, or both, wherein monomers constituting the first non-crystalline polyester resin contains isocyanate monomer for forming the urethane bond, the urea bond, or the both, in an amount of 0.5 mol % or greater to total amount of the monomers, monomers constituting the second non-crystalline polyester resin contain isocyanate monomer for forming the urethane bond, the urea bond, or the both, in an amount of 0.5 mol % or greater to total amount of the monomers, the first non-crystalline polyester resin has Tg of &#x2212;60&#xb0; C. or higher but lower than 10&#xb0; C., and the second non-crystalline polyester resin has Tg of 30&#xb0; C. or higher but lower than 70&#xb0; C.

Toner and image forming method

A yellow toner including: a non-crystalline resin; C.I. Pigment Yellow 185; and a releasing agent, wherein the yellow toner has a glass transition temperature of more than 18&#xb0; C. but less than 40&#xb0; C.

Yellow toner and color image forming method

To provide a toner, which contains: a non-crystalline polyester resin A obtained through a reaction between a non-linear chain reactive precursor and a curing agent, and having a glass transition temperature of &#x2212;60&#xb0; C. to 0&#xb0; C.; a non-crystalline polyester resin B having a glass transition temperature of 40&#xb0; C. to 70&#xb0; C.; and a crystalline polyester resin C, wherein the toner has a glass transition temperature Tg1st of 20&#xb0; C. to 40&#xb0; C. as measured with first heating in differential scanning calorimetry (DSC).

Toner and developer

An electrostatic image forming toner including: toner base particles each containing at least a colorant, a binder resin, and a releasing agent, wherein the binder resin contains a non-crystalline polyester resin A and a crystalline polyester resin B, wherein a ratio of B/(A+B)&#xd7;100 is 10 or more but less than 50 where (A+B) is a total mass of the non-crystalline polyester resin A and the crystalline polyester resin B and 'B' is a mass of the crystalline polyester resin B, and wherein the toner base particles have a TMA compression deformation amount (TMA %) of 10% or less which is measured at 50&#xb0; C. and a relative humidity of 90%.

Electrostatic image forming toner and developer

To provide a toner, including at least: a non-crystalline polyester resin; and a crystalline polyester resin, wherein the toner has a glass transition temperature in a first heating Tg1st and a glass transition temperature in a second heating Tg2nd, and a difference between Tg1st and Tg2nd (Tg1st-Tg2nd) is 10&#xb0; C. or greater, and wherein the crystalline polyester resin is a modified crystalline polyester resin having a urethane skeleton or a urea skeleton, or both thereof.

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Kanagawa, Japan

Rintaro Takahashi