Patents by Inventor Susumu Chiba

Susumu Chiba 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: 10156801
    Abstract: A toner, including: a colorant; a binder resin; and a releasing agent, wherein the binder resin includes a polyester resin, and the toner satisfies requirements (1) and (2) below: (1): G?(50)?3.0×107 Pa and 1.0×105 Pa?G?(60)?1.0×107 Pa, where G?(50) is a storage modulus at 50° C. of the toner and G?(60) is a storage modulus at 60° C. of the toner; and (2): a spin-spin relaxation time of the toner at 50° C. measured by solid echo method of pulse NMR is 1.0 ms or shorter.
    Type: Grant
    Filed: August 13, 2014
    Date of Patent: December 18, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohsuke Nagata, Shinya Nakayama, Tsuyoshi Sugimoto, Daisuke Asahina, Susumu Chiba
  • Patent number: 9921503
    Abstract: A toner including: a pigment; polyester resin A that is insoluble in tetrahydrofuran (THF); and polyester resin B that is soluble in THF, wherein the toner satisfies requirements (1) to (3) below: (1) the polyester resin A includes one or more aliphatic diols including from 3 through 10 carbon atoms, as a component constituting the polyester resin A; (2) the polyester resin B includes at least an alkylene glycol in an amount of 40 mol % or more, as a component constituting the polyester resin B; and (3) a glass transition temperature (Tg1st) of the toner at first heating in differential scanning calorimetry (DSC) of the toner is from 20° C. through 50° C.
    Type: Grant
    Filed: January 6, 2015
    Date of Patent: March 20, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Yamada, Tsuyoshi Sugimoto, Susumu Chiba, Shinsuke Nagai, Kohsuke Nagata, Shinya Nakayama, Yuka Mizoguchi, Suzuka Amemori
  • Patent number: 9885967
    Abstract: Provided is a resin for a toner, which is a copolymer including a crystalline segment, and having a maximum elastic stress value at 100° C. (ES100) of 1,000 Pa or less, and a maximum elastic stress value at 70° C. (ES70) of 1,000 Pa or greater when the temperature is lowered from 100° C. to 70° C., where the maximum elastic stress values are measured according to a large amplitude oscillatory shear procedure.
    Type: Grant
    Filed: August 13, 2014
    Date of Patent: February 6, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Azumi Miyaake, Daisuke Asahina, Toyoshi Sawada, Hiroshi Yamashita, Tsuyoshi Sugimoto, Shinya Nakayama, Susumu Chiba, Satoyuki Sekiguchi
  • Patent number: 9785074
    Abstract: A polyester resin for a toner, the polyester resin including: a segment derived from an alcohol component; and a segment derived from a carboxylic acid component, wherein the alcohol component includes a trivalent or higher aliphatic alcohol, and wherein the polyester resin satisfies Expressions (1) to (3) below: 500 ? Weight ? ? average ? ? molecular ? ? weight ? ? ( Mw ) ( Valence ? ? of ? ? the ? ? trivalent ? ? or higher ? ? aliphatic ? ? alcohol ) × ( Amount ? ? of ? ? the ? ? trivalent ? ? or higher ? ? aliphatic ? ? alcohol ) ? 4 , 000 ; Expression ? ? ( 1 ) 4,000?Weight average molecular weight (Mw)?25,000?? Expression (2); and 0.5?(Amount of the trivalent or higher aliphatic alcohol)?6.
    Type: Grant
    Filed: January 6, 2015
    Date of Patent: October 10, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohsuke Nagata, Shinya Nakayama, Tsuyoshi Sugimoto, Hiroshi Yamada, Susumu Chiba, Shinsuke Nagai, Suzuka Amemori
  • Patent number: 9785075
    Abstract: Provided is a toner containing a binder resin. The binder resin contains a crystalline resin. The toner has a maximum endothermic peak temperature (P1) of from 50° C. to 80° C. and a total endothermic amount (Q) of from 35 J/g to 90 J/g at a first temperature elevation of differential scanning calorimetry. A ratio (Qp/Q) of a total endothermic amount (Qp) of the toner in a temperature range of from 20° C. to the maximum endothermic peak temperature (P1) to the total endothermic amount (Q) of the toner is from 0.65 to 0.83.
    Type: Grant
    Filed: October 11, 2013
    Date of Patent: October 10, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinya Nakayama, Atsushi Yamamoto, Minoru Masuda, Susumu Chiba, Toyoshi Sawada, Hiroshi Yamashita
  • Patent number: 9563141
    Abstract: A toner, including: a copolymerization resin, wherein the copolymerization resin includes: a unit derived from a polyester resin including a polycarboxylic acid having a valence of 2 or more and a polyol having a valence of 2 or more; and a unit derived from a resin having a polyhydroxycarboxylic acid skeleton, where the unit derived from the resin having a polyhydroxycarboxylic acid skeleton is bonded to the unit derived from the polyester resin via at least one of a urethane group and a urea group, and wherein the toner has a relative degree of crystallization of 10% or more and less than 50%.
    Type: Grant
    Filed: January 20, 2014
    Date of Patent: February 7, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Tsuyoshi Sugimoto, Hiroshi Yamashita, Daisuke Asahina, Susumu Chiba, Satoyuki Sekiguchi
  • Patent number: 9557672
    Abstract: A toner, including: a polyester resin, wherein the polyester resin includes a diol component and a crosslink component as constituent components thereof, wherein the diol component contains an aliphatic diol having 3 to 10 carbon atoms in an amount of 50 mol % or more, wherein the crosslink component contains a trihydric or higher aliphatic alcohol, and wherein the toner has a glass transition temperature (Tg1st) of 20° C. to 50° C., where the glass transition temperature (Tg1st) is measured in first heating in differential scanning calorimetry (DSC) of the toner.
    Type: Grant
    Filed: August 13, 2014
    Date of Patent: January 31, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Susumu Chiba, Tsuyoshi Sugimoto, Shinya Nakayama, Kohsuke Nagata, Shinsuke Nagai, Daisuke Asahina
  • Patent number: 9557669
    Abstract: A toner, wherein the toner has glass transition temperature [Tg1st (toner)] of 20° C. to 50° C., where the glass transition temperature [Tg1st (toner)] is measured in a first heating in differential scanning calorimetry (DSC) of the toner, wherein tetrahydrofuran (THF) insoluble matter of the toner has glass transition temperature [Tg2nd (THF insoluble matter)] of ?40° C. to 30° C., where the glass transition temperature [Tg2nd (THF insoluble matter)] is measured in a second heating in differential scanning calorimetry (DSC) of the tetrahydrofuran (THF) insoluble matter, wherein the THF insoluble matter has a storage modulus at 100° C. [G?(100) (THF insoluble matter)] of 1.0×105 Pa to 1.0×107 Pa, and wherein a ratio of a storage modulus of the THF insoluble matter at 40° C. [G?(40) (THF insoluble matter)] to the storage modulus of the THF insoluble matter at 100° C. [G?(100) (THF insoluble matter)] is 3.5×10 or less.
    Type: Grant
    Filed: August 29, 2014
    Date of Patent: January 31, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinsuke Nagai, Shinya Nakayama, Tsuyoshi Sugimoto, Susumu Chiba, Kohsuke Nagata, Daisuke Asahina
  • Publication number: 20170017175
    Abstract: A toner including: a pigment; polyester resin A that is insoluble in tetrahydrofuran (THF); and polyester resin B that is soluble in THF, wherein the toner satisfies requirements (1) to (3) below: (1) the polyester resin A includes one or more aliphatic diols including from 3 through 10 carbon atoms, as a component constituting the polyester resin A; (2) the polyester resin B includes at least an alkylene glycol in an amount of 40 mol % or more, as a component constituting the polyester resin B; and (3) a glass transition temperature (Tg1st) of the toner at first heating in differential scanning calorimetry (DSC) of the toner is from 20° C. through 50° C.
    Type: Application
    Filed: January 6, 2015
    Publication date: January 19, 2017
    Inventors: Hiroshi YAMADA, Tsuyoshi SUGIMOTO, Susumu CHIBA, Shinsuke NAGAI, Kohsuke NAGATA, Shinya NAKAYAMA, Yuka MIZOGUCHI, Suzuka AMEMORI
  • Publication number: 20170010550
    Abstract: A polyester resin for a toner, the polyester resin including: a segment derived from an alcohol component; and a segment derived from a carboxylic acid component, wherein the alcohol component includes a trivalent or higher aliphatic alcohol, and wherein the polyester resin satisfies Expressions (1) to (3) below: 500 ? Weight ? ? average ? ? molecular ? ? weight ? ? ( Mw ) ( Valence ? ? of ? ? the ? ? trivalent ? ? or higher ? ? aliphatic ? ? alcohol ) × ( Amount ? ? of ? ? the ? ? trivalent ? ? or higher ? ? aliphatic ? ? alcohol ) ? 4 , 000 ; Expression ? ? ( 1 ) 4,000?Weight average molecular weight (Mw)?25,000?? Expression (2); and 0.5?(Amount of the trivalent or higher aliphatic alcohol)?6.
    Type: Application
    Filed: January 6, 2015
    Publication date: January 12, 2017
    Inventors: Kohsuke NAGATA, Shinya NAKAYAMA, Tsuyoshi SUGIMOTO, Hiroshi YAMADA, Susumu CHIBA, Shinsuke NAGAI, Suzuka AMEMORI
  • Patent number: 9488925
    Abstract: A magenta toner for electrophotography, including: a polyester resin; and a colorant containing a naphthol-based pigment, wherein the magenta toner for electrophotography satisfies requirements <1> and <2> below: <1> [G?(100)(THF insoluble matter)] is 1.0×105 Pa to 1.0×107 Pa, and a ratio of [G?(40)(THF insoluble matter)] to the [G?(100)(THF insoluble matter)] is 3.5×10 or less, where the [G?(100)(THF insoluble matter)] is a storage modulus at 100° C. of THF insoluble matter of the toner and the [G?(40)(THF insoluble matter)] is a storage modulus at 40° C. of the THF insoluble matter of the toner; and <2> an X-ray diffraction pattern of the naphthol-based pigment in a crystalline state has a plurality of peaks in a range of 0°?2??35°, and a sum of half value widths of the peaks is 5° to 10°.
    Type: Grant
    Filed: February 25, 2015
    Date of Patent: November 8, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryuta Chiba, Shinya Nakayama, Tsuyoshi Sugimoto, Hiroshi Yamada, Susumu Chiba, Shinsuke Nagai, Hiroshi Yamashita, Masana Shiba
  • Publication number: 20160231661
    Abstract: A toner, wherein the toner has glass transition temperature [Tg1st (toner)] of 20° C. to 50° C., where the glass transition temperature [Tg1st (toner)] is measured in a first heating in differential scanning calorimetry (DSC) of the toner, wherein tetrahydrofuran (THF) insoluble matter of the toner has glass transition temperature [Tg2nd (THF insoluble matter)] of ?40° C. to 30° C., where the glass transition temperature [Tg2nd (THF insoluble matter)] is measured in a second heating in differential scanning calorimetry (DSC) of the tetrahydrofuran (THF) insoluble matter, wherein the THF insoluble matter has a storage modulus at 100° C. [G?(100) (THF insoluble matter)] of 1.0×105 Pa to 1.0×107 Pa, and wherein a ratio of a storage modulus of the THF insoluble matter at 40° C. [G?(40) (THF insoluble matter)] to the storage modulus of the THF insoluble matter at 100° C. [G?(100) (THF insoluble matter)] is 3.5×10 or less.
    Type: Application
    Filed: August 29, 2014
    Publication date: August 11, 2016
    Inventors: Shinsuke NAGAI, Shinya NAKAYAMA, Tsuyoshi SUGIMOTO, Susumu CHIBA, Kohsuke NAGATA, Daisuke ASAHINA
  • Publication number: 20160223926
    Abstract: Provided is a resin for a toner, which is a copolymer including a crystalline segment, and having a maximum elastic stress value at 100° C. (ES-100) of 1,000 Pa or less, and a maximum elastic stress value at 70° C. (ES70) of 1,000 Pa or greater when the temperature is lowered from 100° C. to 70° C., where the maximum elastic stress values are measured according to a large amplitude oscillatory shear procedure.
    Type: Application
    Filed: August 13, 2014
    Publication date: August 4, 2016
    Inventors: Azumi MIYAAKE, Daisuke ASAHINA, Toyoshi SAWADA, Hiroshi YAMASHITA, Tsuyoshi SUGIMOTO, Shinya NAKAYAMA, Susumu CHIBA, Satoyuki SEKIGUCHI
  • Publication number: 20160209767
    Abstract: A toner, including: a colorant; a binder resin; and a releasing agent, wherein the binder resin includes a polyester resin, and the toner satisfies requirements (1) and (2) below: (1): G?(50)?3.0×107 Pa and 1.0×105 Pa?G?(60)?1.0×107 Pa, where G?(50) is a storage modulus at 50° C. of the toner and G?(60) is a storage modulus at 60° C. of the toner; and (2): a spin-spin relaxation time of the toner at 50° C. measured by solid echo method of pulse NMR is 1.0 ms or shorter.
    Type: Application
    Filed: August 13, 2014
    Publication date: July 21, 2016
    Inventors: Kohsuke NAGATA, Shinya NAKAYAMA, Tsuyoshi SUGIMOTO, Daisuke ASAHINA, Susumu CHIBA
  • Publication number: 20160209766
    Abstract: A toner, including: a polyester resin, wherein the polyester resin includes a diol component and a crosslink component as constituent components thereof, wherein the diol component contains an aliphatic diol having 3 to 10 carbon atoms in an amount of 50 mol % or more, wherein the crosslink component contains a trihydric or higher aliphatic alcohol, and wherein the toner has a glass transition temperature (Tg1st) of 20° C. to 50° C., where the glass transition temperature (Tg1st) is measured in first heating in differential scanning calorimetry (DSC) of the toner.
    Type: Application
    Filed: August 13, 2014
    Publication date: July 21, 2016
    Inventors: Susumu CHIBA, Tsuyoshi SUGIMOTO, Shinya NAKAYAMA, Kohsuke NAGATA, Shinsuke NAGAI, Daisuke ASAHINA
  • Publication number: 20160004179
    Abstract: A toner, including: a copolymerization resin, wherein the copolymerization resin includes: a unit derived from a polyester resin including a polycarboxylic acid having a valence of 2 or more and a polyol having a valence of 2 or more; and a unit derived from a resin having a polyhydroxycarboxylic acid skeleton, where the unit derived from the resin having a polyhydroxycarboxylic acid skeleton is bonded to the unit derived from the polyester resin via at least one of a urethane group and a urea group, and wherein the toner has a relative degree of crystallization of 10% or more and less than 50%.
    Type: Application
    Filed: January 20, 2014
    Publication date: January 7, 2016
    Applicant: Ricoh Company, Ltd.
    Inventors: Tsuyoshi SUGIMOTO, Hiroshi YAMASHITA, Daisuke ASAHINA, Susumu CHIBA, Satoyuki SEKIGUCHI
  • Patent number: 9207553
    Abstract: To provide a toner including a binder resin and a colorant, wherein the toner has a glass transition temperature by differential scanning calorimetry (DSC) of 20° C. or greater and less than 50° C., an endothermic peak temperature by DSC of 50° C. or greater and less than 80° C. and an amount of compressive deformation at 50° C. by a thermomechanical analysis of 5% or less.
    Type: Grant
    Filed: June 12, 2013
    Date of Patent: December 8, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Tsuyoshi Sugimoto, Hiroshi Yamashita, Susumu Chiba, Satoyuki Sekiguchi
  • Publication number: 20150329668
    Abstract: An aliphatic polyester having a number-average molecular weight of from 500,000 to 2,000,000 includes an ester bonding site and an amide bonding site. The content of the amide bonding site is from 1×10?3% to 1×10?1% by mol based on total weight of the ester bonding site and the amide bonding site.
    Type: Application
    Filed: April 29, 2015
    Publication date: November 19, 2015
    Inventors: Kaori Miyahara, Taichi Nemoto, Yoko Arai, Susumu Chiba, Shohta Kobayashi, Yoshihito Shimada
  • Publication number: 20150329676
    Abstract: A thermoplastic polyimide, including a repeating unit represented by the following General Formula I, wherein an amount of an organic solvent in the thermoplastic polyimide detected by gas chromatography is 5 ppm by mass or less, where in the General Formula I, R represents a divalent organic group.
    Type: Application
    Filed: May 4, 2015
    Publication date: November 19, 2015
    Inventors: Hirokazu MIYAKE, Chiaki TANAKA, Susumu CHIBA, Yukihiro IMANAGA
  • Patent number: 9176406
    Abstract: 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?T2?30° C. (Relation 1), where T1 represents the maximum endothermic peak in the first temperature rising from 0° C. to 100° C. at the temperature rising rate of 10° C./min and T2 represents the maximum exothermic peak in the first temperature falling from 100° C. to 0° C. at the temperature falling rate of 10° C./min as T1 and T2 are measured by diffraction scanning calorimetry (DSC).
    Type: Grant
    Filed: August 5, 2013
    Date of Patent: November 3, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Satoyuki Sekiguchi, Hiroshi Yamashita, Minoru Masuda, Susumu Chiba, Tatsuya Morita, Atsushi Yamamoto, Shinya Nakayama, Masahide Yamada, Kohsuke Nagata, Keiji Makabe, Toyoshi Sawada