Ricoh Company, Ltd.

Azumi Miyaake

Kazumi Suzuki

Masayuki Koyano

Yoshitaka Yamauchi

Masana Shiba

Tatsuya Morita

Mio Kumai

Yuuki Mizutani

Mihoko Matsumoto

Hiroshi Yamashita

Shun Saito

Satoshi Takahashi

Hideki Sugiura

Satoyuki Sekiguchi

Daisuke Asahina

Yuka Mizoguchi

Rintaro Takahashi

Ayano Momose

Kaori Miyahara

Shinya Nakayama

Tsuyoshi Sugimoto

Satoshi Kojima

Takayuki Shimizu

Hiroki Kobayashi

Toyoshi Sawada

Shingo Sakashita

Hiroki Hagiwara

Yuuki Yokohama

Taichi Nemoto

Kiminori Masuda

Susumu Chiba

Amika Sagara

Koichiro Oyama

Ryo Miyakoshi

Maiko Koeda

Yuri Haga

Hiroki Nakane

Kento Sugita

Mizuki Kuroha

An ink including a pigment, water, and a resin is provided. An image formed with the ink on a print medium has a tack force of 6 gf or greater but 13 gf or less when measured at a probe temperature of 100 degrees C., where the image is a solid image formed at a resolution of 1,200 dpi, subsequently irradiated with light of 395 nm for 0.6 seconds, and left to stand at normal temperatures and normal humidities for 30 seconds.

Ink, image forming apparatus, and image forming method

An ink includes water, a coloring material, an organic solvent having a solubility parameter of from 8.0 to 13.0, an urethane resin particle and a metal ion, wherein the organic solvent having the solubility parameter of from 8.0 to 13.0 has a proportion of from 10.0% by mass to 30.0% by mass to the ink, where the metal ion is at least one selected from an alkali metal ion and an alkaline earth metal ion, where the metal ion has a proportion of from 4000 mg/L to 8000 mg/L to the ink.

Ink, ink container, recording device, recording set and recording method

An active-energy-ray-curable composition, a cured material of the active-energy-ray-curable composition satisfying a critical load of 5.0 g or more but 25.0 g or less, the critical load being obtained by a continuous loading test method using a variable normal load friction and wear measurement device, the cured material having an average thickness of 10 &#x3bc;m and being formed by coating the active-energy-ray-curable composition on a substrate and by irradiating and curing the active-energy-ray-curable composition with active energy rays having illuminance of 1.5 W/cmand an amount of irradiation of 200 mJ/cm.

Active-energy-ray-curable composition, active-energy-ray-curable ink, two-dimensional or three-dimensional image forming method, two-dimensional or three-dimensional image forming apparatus, and cured material

An active-energy-ray-curable composition including active-energy-ray-polymerizable compounds, wherein the active-energy-ray-polymerizable compounds include a monofunctional monomer, a bifunctional monomer, and a trifunctional monomer, and wherein the monofunctional monomer, the bifunctional monomer, and the trifunctional monomer satisfy conditions (1) and (2) below: (1) [number of functional groups derived from the monofunctional monomer]&#x3e;[number of functional groups derived from the bifunctional monomer]&#x3e;[number of functional groups derived from the trifunctional monomer]; and (2) a standard deviation of functional group ratios is from 0.003 through 0.030, the functional group ratios being expressed by [number of functional groups derived from N-functional monomer]/([number of functional groups derived from the monofunctional monomer]+[number of functional groups derived from the bifunctional monomer]+[number of functional groups derived from the trifunctional monomer]), the N being mono, bi, or tri.

Active-energy-ray-curable composition, active-energy-ray-curable ink, composition stored container, two-dimensional or three-dimensional image forming apparatus, two-dimensional or three-dimensional image forming method, cured material, and structure

Provided is a resin for a toner, which is a copolymer including a crystalline segment, and having a maximum elastic stress value at 100&#xb0; C. (ES100) of 1,000 Pa or less, and a maximum elastic stress value at 70&#xb0; C. (ES70) of 1,000 Pa or greater when the temperature is lowered from 100&#xb0; C. to 70&#xb0; C., where the maximum elastic stress values are measured according to a large amplitude oscillatory shear procedure.

Resin for toner, toner, developer, image forming apparatus, and process cartridge

Active-energy-ray-curable composition including: monofunctional monomers; and polymerization initiator, cured material of the composition satisfying 0.30&#x2266;D&#x2266;0.85, where D is difference between peak-area-ratios A and B in infrared-ATR and obtained by: the composition is coated on polycarbonate substrate to form coated film having average thickness of 10 &#x3bc;m; the film is irradiated with active energy rays having light quantity of 500 mJ/cmat UV intensity of 1.0 W/cmfor curing; the A is obtained from Formula (1) by infrared-ATR at one portion present from the cured material surface through 1 &#x3bc;m away therefrom toward the substrate, the B is obtained from Formula (1) by infrared-ATR at one portion present from the substrate-cured material interface through 1 &#x3bc;m away therefrom toward the cured material surface,Peak-area (from 1,679 mthrough 1,751 m/peak-area (from 1,096 mthrough 1,130 m)&#x2003;&#x2003;Formula (1), andthe A and B obtained are used to obtain D from Formula (2):=peak-area-ratio&#x2212;peak-area-ratio&#x2003;&#x2003;Formula (2).

Active-energy-ray-curable composition, active-energy-ray-curable ink, composition stored container, image forming method, image forming apparatus, cured material, and image formed matter

A toner including a polyester resin having an amorphous polyester segment is provided. The amorphous polyester segment includes a condensation polymerization product between a carboxylic acid and an alcohol. The carboxylic acid includes both aliphatic and aromatic dicarboxylic acids. The toner deforms with a deformation rate of from 1.0% to 5.0% under a pressure of 100 gf at 40&#xb0; C. and 80% RH. In a binarized image of an AFM phase image of the toner, first phase-contrast images serving as large-phase-difference portions are dispersed in second phase-contrast images serving as small-phase-difference portions, and the first phase-contrast images have a dispersion diameter of 100 nm or less. An endothermic quantity Q1 obtained in a first heating of DSC is from 10 to 50 J/g, and a ratio of an endothermic quantity obtained in the second heating Q2 to that in first heating Q1 is 0.65 or less.

Toner, process cartridge, developer, and image forming apparatus

Provided is a toner, including: a crystalline resin; and a colorant, wherein the toner has a sea island structure in which a crystal region containing the crystalline resin is formed as a sea, and a non-crystalline region containing the colorant is formed as an island.

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 binder resin; a colorant; and wax, wherein the toner has Ta of 30&#xb0; C. to 55&#xb0; C., and Tb&#x2212;Ta of 8&#xb0; C. to 25&#xb0; C., where Ta is a glass transition temperature of the toner determined from a constant heating component of a DSC curve of the toner obtained in a second heating process of temperature modulated differential scanning calorimetry, and Tb is a glass transition temperature of the toner determined from a constant heating component of a DSC curve of the toner obtained in a first heating process of temperature modulated differential scanning calorimetry.

Toner, developer, image forming apparatus, and image forming method

A toner including a binder resin and a colorant, the toner having a core-shell structure containing a core and a shell, wherein the binder resin contains a crystalline polyester resin and a non-crystalline polyester resin, wherein a ratio (A/B) of a mass (A) of the crystalline polyester resin to a mass (B) of the non-crystalline polyester resin is 5/95 to 75/25, and wherein a ratio (Ds/Dc) of a hardness (Ds) of the shell to hardness (Dc) of the core is 1.05 to 1.50 where the hardnesses (Ds) and (Dc) are measured with a scanning probe microscope.

White toner contains a binder resin, a white pigment, and a releasing agent, wherein the white pigment is coated with the releasing agent and dispersed in the binder resin.

White toner, method for producing the same, and development agent, recording medium, printed matter, and image forming apparatus using the same

Growing community of inventors

Kanagawa, Japan

Azumi Miyaake