Ricoh Company, Ltd.

Masahide Yamada

Akinori Saitoh

Masahiro Ohki

Naohiro Watanabe

Shinya Nakayama

Suzuka Amemori

Atsushi Yamamoto

Yukiko Nakajima

Ryota Inoue

Hideyuki Santo

Shigeru Emoto

Chiaki Tanaka

Junichi Awamura

Daiki Yamashita

Tsunemi Sugiyama

Keiji Makabe

Akiyoshi Sabu

Shingo Sakashita

Sonoh Matsuoka

Yoshitaka Yamauchi

Yoshihiro Moriya

Taichi Nemoto

Osamu Uchinokura

Tomomi Suzuki

Shinichi Wakamatsu

Hiroshi Yamashita

Yohichiroh Watanabe

Hiroshi Yamada

Takeshi Takada

Tatsuya Morita

Ryohta Inoue

Takuya Seshita

Toshiki Nanya

Naohito Shimota

Eiji Sawamura

Takayuki Yoshii

Kazuyuki Hirai

Kazushige Yasumatsu

Takamasa Hase

Kazumi Suzuki

Toyoshi Sawada

Daisuke Asahina

Rintaro Takahashi

Minoru Masuda

Tsuyoshi Sugimoto

Satoyuki Sekiguchi

Kohsuke Nagata

Satoshi Izumi

Susumu Chiba

Masahiro Kawamoto

Kousuke Nagata

Tatsunori Kamiyama

Suzuka Amerori

Kazushige Sanyo Chemical Ind Ltd Yasumatsu

Kazuyuki Sanyo Chemical Industries Ltd Hirai

A toner including at least a crystalline resin as a binder resin, wherein a tetrahydrofuran soluble content of the toner includes 5.0% or more as a peak area of a component having a molecular weight of 100,000 or greater in a molecular weight distribution measured by gel permeation chromatography, and the tetrahydrofuran soluble content of the toner has a weight-average molecular weight of 20,000 to 60,000.

Toner, developer using the toner, image forming apparatus

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

Toner contains a binder resin containing a crystalline resin having a urethane and/or urea bonding; and a colorant, wherein in a diffraction spectrum of the toner as measured by an X-ray diffraction instrument, a ratio {C/(C+A)} of an integral intensity C of the spectrum derived from the crystalline structure to an integral intensity A of the spectrum derived from the non-crystalline structure is 0.12 or greater, wherein the toner satisfies the following relation 1: T1&#x2212;T2&#x2266;30&#xb0; C. (Relation 1), where T1 represents the maximum endothermic peak in the first temperature rising from 0&#xb0; C. to 100&#xb0; C. at the temperature rising rate of 10&#xb0; C./min and T2 represents the maximum exothermic peak in the first temperature falling from 100&#xb0; C. to 0&#xb0; C. at the temperature falling rate of 10&#xb0; C./min as T1 and T2 are measured by diffraction scanning calorimetry (DSC).

Toner, development agent, image forming apparatus, and process cartridge

An electrophotographic toner including: a binder resin, wherein the binder resin has one glass transition temperature Tg and the glass transition temperature Tg of the binder resin is within 25&#xb0; C. to 65&#xb0; C. as measured in second heating with a differential scanning calorimeter at a heating rate of 5&#xb0; C./min, and wherein a phase image of the binder resin obtained with an atomic force microscope (AFM) of tapping mode contains first phase difference regions and a second phase difference region such that the first phase difference regions are dispersed in the second phase difference region, where the first phase difference regions correspond to greater phase difference regions and the second phase difference region corresponds to a smaller phase difference region when an intermediate value between a maximum value and a minimum value of the phase differences is used as a threshold.

Electrophotographic toner, developer containing the toner, and image forming apparatus

A resin for toner contains a polyhydroxycarboxylic acid skeleton and a rigid skeleton.

Resin for toner, toner using the resin, and development agent using the toner

A resin for use in toner is provided. The resin comprises an oligomer segment and a soft segment. The oligomer segment comprises a polyhydroxycarboxylic skeleton and an aromatic diol skeleton.

Resin for use in toner, toner using the resin, developer using the toner, image forming apparatus and method using the toner, and method of manufacturing resin

A toner including a binder resin having a glass transition temperature (Tg) observed at least at one point from 25 to 65&#xb0; C. in a differential scanning calorimeter at a rate of temperature increase of 5&#xb0; C./min, wherein the toner has a structure in which a structure appearing as a high phase difference image is dispersed in a structure appearing as a low phase difference image in a two-dimensional phase difference image observed by tapping mode AFM, and an X-ray diffraction chart in which a peak originated from an crystalline resin is observed in a range of a diffraction angle 2&#x3b8; of from 20 to 25&#xb0;, and wherein a ratio (I1/I2) of an intensity of the peak originated from an crystalline resin to an intensity (I2) of a halo originated from an amorphous composition is from 0.2 to 1.

Toner and developer

A development agent containing toner that contains a binder resin having a crystalline resin that has a urethane and/or urea bond in its main chain, a coloring agent, and an organically modified inorganic laminate compound in which organic ions are at least partially substituted for ions present between layers of the organically modified inorganic laminate compound, and toner carrier that contains a core material whose surface is coated with a coating layer having a condensed compound of a melamine resin and/or a guanamine resin and an acrylic resin having a hydroxyl group.

Development agent and image forming apparatus employing same

A toner, including: a crystalline resin containing a urethane bond, a urea bond, or both thereof; and a compound represented by the following General Formula (1), wherein an amount of the compound represented by the General Formula (1) is 0.01% by mass to 0.25% by mass:CHR&#x2003;&#x2003;General Formula (1)

Toner, developer and image forming apparatus

The toner includes a pigment; and a block copolymer having a polyester block A including a residual group of a hydroxycarboxylic acid, and a polyester block B including an anionic group. When cross-section of the block copolymer is observed by a tapping mode atomic force microscope to obtain a phase image of the cross-section, the polyester block B, which has relatively large phase delay, is dispersed as domains having an average size of from 20 nm to 100 nm in a domain of the polyester block A, which has relatively small phase delay. The block copolymer has a first glass transition temperature of from &#x2212;20&#xb0; C. to 20&#xb0; C., and a second glass transition temperature of from 35&#xb0; C. to 65&#xb0; C. when the first and second glass transition temperatures are determined from a thermogram obtained by subjecting the block copolymer to differential scanning calorimetry (DSC) at a temperature rising speed of 5&#xb0; C./min.

Toner, developer including the toner, image forming apparatus using the toner, and block copolymer

A toner includes a binder resin, a coloring agent, and a releasing agent containing two or more kinds of alkyl monoester compounds having a different number of carbon atoms in a range of from 30 to 50 carbon atoms. The toner has a crystallinity of 10% or more as measured by x-ray diffraction and/or the binder resin is a crystalline resin in an amount of 50% by weight or more of the binder resin. The two or more kinds of alkyl monoester compounds include a component A accounting for the largest amount ranging from 30% by weight to less than 50% by weight of the releasing agent and a component B accounting for the second largest amount ranging from 10% by weight to less than 50% by weight of the releasing agent.

Toner, development agent, and image forming apparatus using the same

An electrophotographic toner, including: a binder resin; a colorant; and an organically-modified layered inorganic mineral, wherein the binder resin contains 50% by mass or more of a crystalline resin relative to the binder resin, and the crystalline resin contains a resin having a sulfonic acid group, and wherein an amount of the sulfonic acid group is 0.1% by mass to 2.0% by mass relative to the resin having the sulfonic acid group.

Electrophotographic toner, developer, and image forming apparatus

A developer, including a toner including a binder resin comprising a crystalline resin; and a colorant, and a resin carrier comprising a resin; a magnetic particulate material having a magnetic anisotropy, dispersed in the resin, and having a saturated magnetization of from 16 to 30 emu/g, a coercive force of from 15 to 40 kA/m and an average particle diameter not less than 15 &#x3bc;m and less than 100 &#x3bc;m.

Developer for electrophotography, image forming apparatus and process cartridge

Growing community of inventors

Numazu, Japan

Masahide Yamada