Patents by Inventor Junichi Awamura

Junichi Awamura has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11340540
    Abstract: Provided is an image forming apparatus including an image bearer, a developing unit configured to develop with a toner, an intermediate transfer member, and a transferring unit, wherein the intermediate transfer member is a laminate including a base layer and an elastic layer including particles at a surface thereof to form convex-concave shapes at the surface, the particles have volume resistivity of from 1×100 ohm*cm through 1×109 ohm*cm, the toner includes additive, an amount of the additive separated from the toner is from 20 percent by mass through 35 percent by mass relative to a total amount of the additive in the toner when a toner dispersion liquid in which the toner is dispersed in a dispersant is irradiated with ultrasonic wave vibration with an irradiation energy dose of 4 kJ, and the toner has a dielectric constant of 2.6 or greater but 3.9 or less.
    Type: Grant
    Filed: December 21, 2018
    Date of Patent: May 24, 2022
    Assignee: Ricoh Company, Ltd.
    Inventors: Akio Takei, Daisuke Inoue, Daichi Hisakuni, Hidetaka Kubo, Masahiro Ohmori, Junichi Awamura
  • Patent number: 11036154
    Abstract: A toner is provided. The toner comprises a colorant, a release agent, and a binder resin. The binder resin comprises a crystalline polyester resin and an amorphous polyester resin. The amorphous polyester resin comprises an amorphous polyester resin A and an amorphous polyester resin B. The amorphous polyester resin A comprises an isocyanurate backbone and at least one of urethane bond and urea bond. The amorphous polyester resin B comprises a trimellitic acid backbone and at least one of urethane bond and urea bond.
    Type: Grant
    Filed: November 26, 2018
    Date of Patent: June 15, 2021
    Assignee: Ricoh Company, Ltd.
    Inventors: Masayuki Ukigaya, Junichi Awamura, Hiroshi Yamada, Kohsuke Nagata, Hiroyuki Takeda
  • Publication number: 20210063916
    Abstract: Provided is an image forming apparatus including an image bearer, a developing unit configured to develop with a toner, an intermediate transfer member, and a transferring unit, wherein the intermediate transfer member is a laminate including a base layer and an elastic layer including particles at a surface thereof to form convex-concave shapes at the surface, the particles have volume resistivity of from 1×100 ohm*cm through 1×109 ohm*cm, the toner includes additive, an amount of the additive separated from the toner is from 20 percent by mass through 35 percent by mass relative to a total amount of the additive in the toner when a toner dispersion liquid in which the toner is dispersed in a dispersant is irradiated with ultrasonic wave vibration with an irradiation energy dose of 4 kJ, and the toner has a dielectric constant of 2.6 or greater but 3.9 or less.
    Type: Application
    Filed: December 21, 2018
    Publication date: March 4, 2021
    Inventors: Akio TAKEI, Daisuke INOUE, Daichi HISAKUNI, Hidetaka KUBO, Masahiro OHMORI, Junichi AWAMURA
  • Publication number: 20190171122
    Abstract: A toner is provided. The toner comprises a colorant, a release agent, and a binder resin. The binder resin comprises a crystalline polyester resin and an amorphous polyester resin. The amorphous polyester resin comprises an amorphous polyester resin A and an amorphous polyester resin B. The amorphous polyester resin A comprises an isocyanurate backbone and at least one of urethane bond and urea bond. The amorphous polyester resin B comprises a trimellitic acid backbone and at least one of urethane bond and urea bond.
    Type: Application
    Filed: November 26, 2018
    Publication date: June 6, 2019
    Inventors: Masayuki UKIGAYA, Junichi AWAMURA, Hiroshi YAMADA, Kohsuke NAGATA, Hiroyuki TAKEDA
  • Patent number: 10303071
    Abstract: A non-magnetic toner is provided. The non-magnetic toner comprises a polyester resin, a release agent, and a colorant. A storage elastic modulus at 100° C. (G?(100° C.)) of the toner is from 1.0×103 to 1.0×106 Pa, and a storage elastic modulus at 160° C. (G?(160° C.)) of the toner is from 1.0×102 to 1.0×104 Pa. A ratio of loss elastic modulus to storage elastic modulus at 100° C. (tan ?(100° C.)) of the toner is greater than that at 130° C. (tan ?(130° C.)), and the tan ?(100° C.) and the tan ?(130° C.) are each within the range of from 1 to 2.
    Type: Grant
    Filed: January 18, 2018
    Date of Patent: May 28, 2019
    Assignee: Richoh Company, Ltd.
    Inventors: Hiroyuki Takeda, Junichi Awamura, Hiroshi Yamada, Akira Tanaka
  • Patent number: 10303072
    Abstract: A toner is provided. The toner contains a polyester resin. The toner has a glass transition temperature (Tg1st) at first temperature rising of differential scanning calorimetry (DSC) of from 45° C. to 65° C. The toner includes a component insoluble in tetrahydrofuran (THF) having two glass transition temperatures (Tga1st and Tgb1st) at the first temperature rising of DSC, where Tga1st is in a range of ?45° C. to 5° C. and Tgb1st is in a range of 45° C. to 70° C. The toner includes a component soluble in THF having a glass transition temperature (Tg2nd) at second temperature rising of DSC of from 40° C. to 65° C.
    Type: Grant
    Filed: February 6, 2018
    Date of Patent: May 28, 2019
    Assignee: Ricoh Company, Ltd.
    Inventors: Akira Tanaka, Hiroyuki Takeda, Junichi Awamura, Hiroshi Yamada, Daichi Hisakuni, Yasuo Kamada
  • Publication number: 20180253022
    Abstract: A non-magnetic toner is provided. The non-magnetic toner comprises a polyester resin, a release agent, and a colorant. A storage elastic modulus at 100° C. (G?(100° C.)) of the toner is from 1.0×103 to 1.0×106 Pa, and a storage elastic modulus at 160° C. (G?(160° C.)) of the toner is from 1.0×102 to 1.0×104 Pa. A ratio of loss elastic modulus to storage elastic modulus at 100° C. (tan ?(100° C.)) of the toner is greater than that at 130° C. (tan ?(130° C.)), and the tan ?(100° C.) and the tan ?(130° C.) are each within the range of from 1 to 2.
    Type: Application
    Filed: January 18, 2018
    Publication date: September 6, 2018
    Inventors: Hiroyuki TAKEDA, Junichi AWAMURA, Hiroshi YAMADA, Akira TANAKA
  • Patent number: 10054864
    Abstract: 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° C. through 55° 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° 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° C. and 70% RH is in a range of from 15% through 50%.
    Type: Grant
    Filed: January 4, 2016
    Date of Patent: August 21, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomoki Murayama, Ryota Inoue, Masana Shiba, Daisuke Inoue, Junichi Awamura, Yoshitsugu Kimura, Rintaro Takahashi
  • Publication number: 20180224763
    Abstract: A toner is provided. The toner contains a polyester resin. The toner has a glass transition temperature (Tg1st) at first temperature rising of differential scanning calorimetry (DSC) of from 45° C. to 65° C. The toner includes a component insoluble in tetrahydrofuran (THF) having two glass transition temperatures (Tga1st and Tgb1st) at the first temperature rising of DSC, where Tga1st is in a range of ?45° C. to 5° C. and Tgb1st is in a range of 45° C. to 70° C. The toner includes a component soluble in THF having a glass transition temperature (Tg2nd) at second temperature rising of DSC of from 40° C. to 65° C.
    Type: Application
    Filed: February 6, 2018
    Publication date: August 9, 2018
    Inventors: Akira TANAKA, Hiroyuki TAKEDA, Junichi AWAMURA, Hiroshi YAMADA, Daichi HISAKUNI, Yasuo KAMADA
  • Patent number: 9989869
    Abstract: 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±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.
    Type: Grant
    Filed: January 5, 2016
    Date of Patent: June 5, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Daisuke Inoue, Naohiro Watanabe, Ryota Inoue, Masana Shiba, Junichi Awamura, Shingo Sakashita, Tomoki Murayama, Yoshitsugu Kimura, Rintaro Takahashi, Akio Takei
  • Publication number: 20180052403
    Abstract: 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±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.
    Type: Application
    Filed: January 5, 2016
    Publication date: February 22, 2018
    Inventors: Daisuke INOUE, Naohiro WATANABE, Ryota INOUE, Masana SHIBA, Junichi AWAMURA, Shingo SAKASHITA, Tomoki MURAYAMA, Yoshitsugu KIMURA, Rintaro TAKAHASHI, Akio TAKEI
  • Patent number: 9523931
    Abstract: To provide a toner, which contains silica particles containing first silica particles, and second silica particles, wherein the toner is a toner produced by depositing the silica particles on surfaces of base particles, the first silica particles have an average primary particle diameter of 75 nm to 250 nm, the second silica particles have an average primary particle diameter of 10 nm to 50 nm, a mass ratio of the first silica particles to the base particles is 0.010 to 0.040, a mass ratio of the second silica particles to the base particles is 0.005 to 0.030, a liberation ratio of the silica particles from the toner by a ultrasonic vibration method is 5% by mass to 20% by mass, and an amount of particles having primary particle diameters of 30 nm or smaller in the silica particles librated from the toner by the ultrasonic vibration method is 20% by number or less.
    Type: Grant
    Filed: January 30, 2014
    Date of Patent: December 20, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Satoshi Kojima, Junichi Awamura, Tsuneyasu Nagatomo, Shingo Sakashita, Tomoki Murayama, Masaya Fukuda
  • Publication number: 20160195827
    Abstract: 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° C. through 55° 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° 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° C. and 70% RH is in a range of from 15% through 50%.
    Type: Application
    Filed: January 4, 2016
    Publication date: July 7, 2016
    Inventors: Tomoki Murayama, Ryota Inoue, Masana Shiba, Daisuke Inoue, Junichi Awamura, Yoshitsugu Kimura, Rintaro Takahashi
  • Patent number: 9291931
    Abstract: Provided is an electrostatic charge image developing toner, including: toner base particles including a polyester resin as a binder resin; and an external additive on the surface of the toner base particles. The external additive includes silica. The silica is produced by sol-gel method, and is aspherical. The percentage of change in the specific surface area of the toner when it is stored under high-temperature, high-humidity conditions is from 25% to 45%.
    Type: Grant
    Filed: February 18, 2014
    Date of Patent: March 22, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Junichi Awamura, Tsuneyasu Nagatomo, Satoshi Kojima, Shingo Sakashita, Tomoki Murayama, Masaya Fukuda
  • Patent number: 9274445
    Abstract: A toner set, including: a transparent toner including a binder resin a, a releasing agent a and no colorant; and one or more color toners, each including a binder resin b, a colorant b and a releasing agent b, wherein the binder resin a includes a non-crystalline resin ? and a crystalline resin ?, the binder resin b includes a non-crystalline resin ? and a crystalline resin ?, the releasing agent a has an average particle diameter as a long diameter of 0.2 ?m to 2.0 ?m, and there is a relationship of 1<A/B<1.5, where A is an area of the releasing agent a in a transparent toner cross-section from a surface thereof to a ?-depth of a volume-average particle diameter, and B is an area of the releasing agent b in a color-toner cross-section from a surface thereof to a ?-depth of a volume-average particle diameter.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: March 1, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Junichi Awamura, Teruki Kusahara, Satoshi Ogawa, Daisuke Ito, Daisuke Inoue, Osamu Uchinokura, Satoshi Kojima, Tsuneyasu Nagatomo, Mamoru Hozumi, Syouko Satoh
  • Patent number: 9201326
    Abstract: A toner including: a binder resin containing a non-crystalline resin and a crystalline resin; a colorant; and, a releasing agent, wherein the releasing agent has a melting point of 55° C. to 80° C., and wherein the toner satisfies the following Expressions 1 and 2: (Expression 1): 20,000 Pa·s?G1?50,000 Pa·s; and (Expression 2): (G4/G2)/(G3/G1) 1.00, where G1 is a storage modulus, G2 is a loss modulus, G3 is a storage modulus and G4 is a loss modulus, and the storage modulus G1 and the loss modulus G2 are measured at 80° C. when the toner is heated from 70° C. to 150° C. and the storage modulus G3 and the loss modulus G4 are measured at 80° C. when the toner heated to 150° C. is cooled to 70° C.
    Type: Grant
    Filed: December 28, 2012
    Date of Patent: December 1, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryuuta Yoshida, Takahiro Honda, Junichi Awamura, Osamu Uchinokura, Masaki Watanabe, Daisuke Inoue, Tomoki Murayama, Mamoru Hozumi
  • Patent number: 9201325
    Abstract: A toner including a binder resin which contains a crystalline polyester resin and a non-crystalline polyester resin, wherein the crystalline polyester resin has at least two diffraction peaks in a range of 20°<2?<25° as detected by X-ray diffraction measurement, and has a melting point which is 60° C. or higher but lower than 80° C., and wherein the diffraction peaks each have a half width which is less than 1.0°.
    Type: Grant
    Filed: April 14, 2011
    Date of Patent: December 1, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Tsuyoshi Sugimoto, Osamu Uchinokura, Satoshi Ogawa, Junichi Awamura, Satoshi Kojima, Daisuke Ito, Teruki Kusahara, Daisuke Inoue, Mamoru Hozumi, Shoko Sato
  • Patent number: 9152084
    Abstract: A toner housing container includes: a container body housing a toner; a conveying portion; a pipe receiving port; and an uplifting portion. Flow rate index of the toner measured by powder rheometer and represented by “flow rate index=(total energy at a rotation speed of 10 mm/s)/(total energy at a rotation speed of 100 mm/s)” is in a range of “1.8?flow rate index?6.5”. Container body includes protruding portion protruding from container body interior side of container opening portion toward one end of container body. Uplifting portion includes: uplifting wall surface extending from container body internal wall surface toward protruding portion; and curving portion curving to conform to protruding portion. When the toner housing container is mounted on the toner conveying device, the protruding portion is present between the curving portion and the toner receiving port of the conveying pipe being inserted.
    Type: Grant
    Filed: May 20, 2014
    Date of Patent: October 6, 2015
    Assignee: RICOH COMPANY, LTD.
    Inventors: Masana Shiba, Shingo Sakashita, Junichi Awamura, Tomoki Murayama, Chihiro Kikuchi, Masaya Fukuda, Hiroshi Hosokawa, Shunji Katoh, Shinji Tamaki, Hiroshi Ikeguchi, Kenji Kikuchi, Michiharu Suzuki
  • Patent number: 9086647
    Abstract: A developing device, including: a developer bearing member, which is disposed opposite to an electrostatic latent image bearing member and which bears thereon a developer for developing an electrostatic latent image formed on the electrostatic latent image bearing member and conveys the developer to a developing region, wherein the developer includes a toner and a carrier, the toner containing: a toner base containing a binder resin and a colorant; and an external additive, wherein the external additive contains coalescent particles each made up of a plurality of coalescing primary particles, and wherein a work function Wc of the carrier and a work function Ws of the developer bearing member satisfy a relationship of the following formula (1): Ws?Wc?0.4 eV??(1).
    Type: Grant
    Filed: September 10, 2013
    Date of Patent: July 21, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Shingo Sakashita, Junichi Awamura, Tsuneyasu Nagatomo, Satoshi Kojima, Tomoki Murayama
  • Patent number: 9069288
    Abstract: Toner housing container includes: container body mountable on toner conveying device and housing toner supplied into toner conveying device; conveying portion provided in container body and conveying toner from longer direction one end of container body to other end at which container opening portion is provided; pipe receiving port provided at container opening portion and receiving conveying pipe fixed to toner conveying device; and uplifting portion to move toner conveyed by conveying portion toward toner receiving port of conveying pipe. Toner has loose apparent density of 0.28 g/cm3 to 0.53 g/cm3. Container body includes protruding portion protruding from container body interior side of container opening portion toward one end. Uplifting portion includes uplifting wall surface extending from internal wall surface of container body toward protruding portion, and curving portion curving to conform to protruding portion.
    Type: Grant
    Filed: May 20, 2014
    Date of Patent: June 30, 2015
    Assignee: RICOH COMPANY, LTD.
    Inventors: Satoshi Kojima, Junichi Awamura, Tsuneyasu Nagatomo, Shingo Sakashita, Tomoki Murayama, Masaya Fukuda, Hiroshi Hosokawa, Shunji Katoh, Shinji Tamaki, Hiroshi Ikeguchi, Kenji Kikuchi, Michiharu Suzuki