Patents by Inventor Ryuji Murayama

Ryuji Murayama 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).

  • Publication number: 20240134300
    Abstract: Provided is a toner comprising a toner particle comprising a binder resin and a. silica fine particle, wherein a total content of a polyvalent metal elements in the toner particle is 0.10 to 2.50 ?mol/g, a number-average particle diameter of a primary particle of the silica fine particle is 40 to 500 nm, and in the DD/MAS measurement of solid 29Si-NMR of the silica fine particle, peak PD1 corresponding to a silicon atom represented by Sia in a structure represented by formula (1) and peak PD2 corresponding to a silicon atom represented by Sib in a structure represented by formula (2) are observed, and when an area of the peak PD1 is defined as SD1 and an area of the peak PD2 is defined as SD2, SD1 and SD2 satisfy: 1.2?(SD1+SD2)/SD1?10.0.
    Type: Application
    Filed: October 2, 2023
    Publication date: April 25, 2024
    Inventors: HITOSHI SANO, SHIN KITAMURA, TORU TAKAHASHI, RYUICHIRO MATSUO, RYUJI MURAYAMA, TAKAKUNI KOBORI, YOSHIHIRO OGAWA
  • Publication number: 20240069457
    Abstract: The toner contains binder resin-containing toner particles and silica fine particle S1, wherein the weight-average particle diameter of the toner is 4.0-15.0 ?m, both inclusive, peaks originating with the silica fine particle S1 are observed in 29 Si-NMR measurement of the silica fine particle S1, and, in the spectrum obtained by 29Si CP/MAS NMR or 29Si DD/MAS NMR, the peak area of a peak corresponding to the D1 unit structure in the silica fine particle S1, the peak area of a peak corresponding to the D2 unit structure in the silica fine particle S1, and the peak area of a peak corresponding to the Q unit structure in the silica fine particle S1 satisfy a prescribed relationship.
    Type: Application
    Filed: October 25, 2023
    Publication date: February 29, 2024
    Inventors: RYUJI MURAYAMA, SHIN KITAMURA, TORU TAKAHASHI, DAISUKE TSUJIMOTO, RYUICHIRO MATSUO, HITOSHI SANO, NOBUYUKI FUJITA, SHUJI YAMADA, YUKA GUNJI, TAKAKUNI KOBORI, YOSHIHIRO OGAWA, ATSUHIKO OHMORI, HIROKI KAGAWA, KEISUKE ADACHI, TOMOKO SUGITA
  • Publication number: 20230408940
    Abstract: A toner comprising a toner particle and a silica fine particle A on a surface of the toner particle, wherein: a weight-average particle diameter of the toner is 4.0 to 15.0 ?m; the silica fine particle A comprises a silicone oil and a carbon loss ratio when the silica fine particle A is washed with hexane is 5 to 70%; and an area of each peak obtained in a solid-state CP/MAS 29Si-NMR measurement of the silica fine particle A and of the silica fine particle A after washing thereof with hexane is in a specific range.
    Type: Application
    Filed: April 27, 2023
    Publication date: December 21, 2023
    Inventors: RYUICHIRO MATSUO, TORU TAKAHASHI, DAISUKE TSUJIMOTO, SHIN KITAMURA, RYUJI MURAYAMA, HITOSHI SANO, NOBUYUKI FUJITA, SHUJI YAMADA, YUKA GUNJI, TAKAKUNI KOBORI, YOSHIHIRO OGAWA
  • Publication number: 20230408943
    Abstract: A toner comprising a toner particle and a silica fine particle A on a surface of the toner particle, wherein: a weight-average particle diameter of the toner is 4.0 to 15.0 ?m; the silica fine particle A is a treated silica fine particle having been surface-treated; and areas of each peak which is obtained by a solid-state DD/MAS 29Si-NMR measurement of the silica fine particle A and the silica fine particle A after washing thereof with hexane is in a specific range, and a full width at half maximum of the peak which is obtained by a solid-state DD/MAS 29Si-NMR measurement of the silica fine particle A is in a specific range.
    Type: Application
    Filed: April 27, 2023
    Publication date: December 21, 2023
    Inventors: SHIN KITAMURA, TORU TAKAHASHI, DAISUKE TSUJIMOTO, RYUICHIRO MATSUO, RYUJI MURAYAMA, HITOSHI SANO, NOBUYUKI FUJITA, SHUJI YAMADA, YUKA GUNJI, TAKAKUNI KOBORI, YOSHIHIRO OGAWA
  • Publication number: 20230408944
    Abstract: A toner which has a toner particle and silica fine particle A on a surface of the toner particle, wherein a weight average particle diameter of the toner is 4.0 to 15.0 ?m, a carbon loss ratio when the silica fine particle A is washed with hexane is 5 to 70%, and a temperature at which a differential coefficient of a nine-point moving average of integrated values integrated from 35° C. reaches 4000 or more for an intensity of an obtained ion having a mass number (M/z) of 207 is 270° C. or higher, when mass spectrometry is carried out at a sampling interval of 0.4 seconds while heating the silica fine particle A under specific conditions.
    Type: Application
    Filed: April 27, 2023
    Publication date: December 21, 2023
    Inventors: DAISUKE TSUJIMOTO, TORU TAKAHASHI, RYUICHIRO MATSUO, SHIN KITAMURA, NOBUYUKI FUJITA, RYUJI MURAYAMA, HITOSHI SANO, TAKAKUNI KOBORI, YOSHIHIRO OGAWA
  • Patent number: 11762307
    Abstract: A toner having a toner particle containing a binder resin and a styrene-acrylic resin, the toner being characterized in that the styrene-acrylic resin is a graft polymer having an aliphatic hydrocarbon compound segment and a styrene-acrylic segment, the styrene-acrylic segment has a specific monomer unit, the melting point of the styrene-acrylic segment is from 30° C. to 80° C., and when the toner is measured using a FT-IR ATR method, the intensity assigned to the styrene-acrylic resin and the intensity assigned to the binder resin satisfy a specific relationship.
    Type: Grant
    Filed: August 7, 2020
    Date of Patent: September 19, 2023
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Junichi Tamura, Takaho Shibata, Ryuji Murayama, Kenta Mitsuiki, Megumi Shino, Hironori Minagawa
  • Publication number: 20220236660
    Abstract: A magnetic carrier including: a magnetic core; and a coating resin that coats a surface of the magnetic core, wherein the resin coating layer has a thickness of 50 nm or more, a coating resin, which forms the resin coating layer, contains a resin S having an organosilicon polymer moiety, and when a surface and a position at a depth of 20 nm from the surface of the magnetic carrier are analyzed by X-ray photoelectron spectroscopy, an amount of silicon element as determined by the analysis has a ratio within a specific range at respective positions.
    Type: Application
    Filed: January 21, 2022
    Publication date: July 28, 2022
    Inventors: Ryuji Murayama, Hironori Minagawa, Yuto Onozaki, Nobuhiro Yoshida
  • Publication number: 20220236658
    Abstract: A magnetic carrier includes a magnetic core and a coating resin that covers a surface of the magnetic core. The coating resin includes a resin A and a resin B. A content of the resin A is 1 to 50% by mass, and a content of the resin B is 50 to 99% by mass, with respect to the coating resin. The resin A has a particular unit Y1 and a particular unit Y2, and the resin B contains 0.1% by mass or less of the particular unit Y2. When a mass of the resin A is represented by X, a mass of the unit Y1 is represented by Ma, and a mass of the unit Y2 is represented by Mb, 0.90?(Ma+Mb)/X?1.00 and 1.00?Ma/Mb?30.0 are satisfied, and also 0?|SPa?SPb|?2.0 is satisfied.
    Type: Application
    Filed: January 24, 2022
    Publication date: July 28, 2022
    Inventors: Ryuji Murayama, Yuto Onozaki, Nobuhiro Yoshida, Hironori Minagawa
  • Publication number: 20220236657
    Abstract: A magnetic carrier including a magnetic core and a coating resin configured to coat the surface of the magnetic core. The coating resin contains a graft resin A and a graft resin B. The coating resin (i) contains 1.0 mass % or more and 50.0 mass % or less of the graft resin A, and (ii) contains 50.0 mass % or more and 99.0 mass % or less of the graft resin B. The graft resin A has a unit Y1 represented by formula (1) and a unit Y2 represented by formula (2). The graft resin B (i) is a comb-shaped polymer having, as a branch, at least one moiety selected from, for example, a styrene-based polymer moiety and a (meth)acrylate-based polymer moiety, and (ii) contains the polysiloxane structure moiety at a content of 0.1 mass % or less.
    Type: Application
    Filed: January 26, 2022
    Publication date: July 28, 2022
    Inventors: Yuto Onozaki, Ryuji Murayama, Nobuhiro Yoshida, Hironori Minagawa
  • Publication number: 20210389688
    Abstract: A negative-charging toner comprising a toner particle comprising a binder resin and an organic-inorganic composite fine particle comprising resin fine particles and inorganic fine particles A, wherein the organic-inorganic composite fine particle is negative charging, the organic-inorganic composite fine particle has a structure in which at least a part of the inorganic fine particle A is embedded in the resin fine particle, a number average particle diameter Db of the organic-inorganic composite fine particle is 50 to 350 nm, and a plurality of convex portions derived from the inorganic fine particles A are present on the surface of the organic-inorganic composite fine particle.
    Type: Application
    Filed: June 2, 2021
    Publication date: December 16, 2021
    Inventors: Takaho Shibata, Ryuji Murayama, Ryuichiro Matsuo, Yuto Onozaki, Kenta Mitsuiki, Megumi Shino, Hironori Minagawa
  • Patent number: 11131938
    Abstract: A toner comprises a toner particle including a binder resin, and inorganic fine particles A and silica particles B, wherein the inorganic fine particle A has a rectangular parallelepiped shape; an amount of the inorganic fine particles A is 0.3 to 3.0 mass parts per 100 mass parts of the toner particles; a number average particle diameter of the silica particles B is 80 to 200 nm; a fixing ratio of the inorganic fine particle A is 25% to 70%; where a separation amount of the inorganic fine particles A is denoted by YA (mg), and a separation amount of the silica particles is denoted by YB (mg), YA is 3.00 to 18.0, YA and YB satisfy the following formula, YA/YB>0.75, and a surface potential difference C in a rubbing test using the inorganic fine particle A and the binder resin is ?70 V to +70 V.
    Type: Grant
    Filed: August 13, 2019
    Date of Patent: September 28, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Ryuji Murayama, Takaho Shibata, Junichi Tamura, Kenta Mitsuiki, Megumi Shino, Hironori Minagawa
  • Publication number: 20210055668
    Abstract: A toner having a toner particle containing a binder resin and a styrene-acrylic resin, the toner being characterized in that the styrene-acrylic resin is a graft polymer having an aliphatic hydrocarbon compound segment and a styrene-acrylic segment, the styrene-acrylic segment has a specific monomer unit, the melting point of the styrene-acrylic segment is from 30° C. to 80° C., and when the toner is measured using a FT-IR ATR method, the intensity assigned to the styrene-acrylic resin and the intensity assigned to the binder resin satisfy a specific relationship.
    Type: Application
    Filed: August 7, 2020
    Publication date: February 25, 2021
    Inventors: Junichi Tamura, Takaho Shibata, Ryuji Murayama, Kenta Mitsuiki, Megumi Shino, Hironori Minagawa
  • Patent number: 10877386
    Abstract: A toner comprises a toner particle and an external additive, the toner satisfies a certain relationship with regard to ?l (C/m2) and ?s (C/m2). The toner is divided into two groups i.e. a first group and a second group with inertial classifier, the first group including a larger size of the toner particles, and the second group including a smaller size of the toner particles, and the number of the toner particles in the first group being substantially equal to the number of the toner particles in the second group. Then, al (C/m2) represents an absolute value of average surface charge density of the toner included in the first group, and ?s (C/m2) represents an absolute value of average surface charge density of the toner included in the second group.
    Type: Grant
    Filed: August 6, 2019
    Date of Patent: December 29, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Ryuji Murayama, Junichi Tamura, Kentaro Kamae, Hayato Ida, Daisuke Yamashita, Masaharu Miura, Takaho Shibata, Wakiko Katsumata, Yuichi Mizo
  • Patent number: 10775710
    Abstract: A toner includes a toner particle containing a binder resin and a silica fine particle A on a surface of the toner particle, wherein D50 on a number basis of the toner is 3.0 to 6.0 the silica fine particle A is a particle having a particle diameter of 80 to 500 nm, the particle diameter being confirmable by observing the toner with a SEM, and when the average coverage with the silica fine particle A determined by image analysis of a particle group of a small particle diameter side of the toner with a SEM is set to Ss and the average coverage with the silica fine particle A determined by image analysis of a particle group of a large particle diameter side of the toner with a scanning electron microscope is set to S1, Ss is 20 to 70 area %, Ss and S1 satisfy S1/Ss?0.80.
    Type: Grant
    Filed: August 7, 2019
    Date of Patent: September 15, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kentaro Kamae, Ryuji Murayama, Junichi Tamura, Masaharu Miura, Hayato Ida, Takaho Shibata, Koh Ishigami, Yuichi Mizo
  • Publication number: 20200064751
    Abstract: A toner comprises a toner particle including a binder resin, and inorganic fine particles A and silica particles B, wherein the inorganic fine particle A has a rectangular parallelepiped shape; an amount of the inorganic fine particles A is 0.3 to 3.0 mass parts per 100 mass parts of the toner particles; a number average particle diameter of the silica particles B is 80 to 200 nm; a fixing ratio of the inorganic fine particle A is 25% to 70%; where a separation amount of the inorganic fine particles A is denoted by YA (mg), and a separation amount of the silica particles is denoted by YB (mg), YA is 3.00 to 18.0, YA and YB satisfy the following formula, YA/YB>0.75, and a surface potential difference C in a rubbing test using the inorganic fine particle A and the binder resin is ?70 V to +70 V.
    Type: Application
    Filed: August 13, 2019
    Publication date: February 27, 2020
    Inventors: Ryuji Murayama, Takaho Shibata, Junichi Tamura, Kenta Mitsuiki, Megumi Shino, Hironori Minagawa
  • Publication number: 20200057397
    Abstract: A toner comprises a toner particle and an external additive, the toner satisfies a certain relationship with regard to ?l (C/m2) and ?s (C/m2). The toner is divided into two groups i.e. a first group and a second group with inertial classifier, the first group including a larger size of the toner particles, and the second group including a smaller size of the toner particles, and the number of the toner particles in the first group being substantially equal to the number of the toner particles in the second group. Then, al (C/m2) represents an absolute value of average surface charge density of the toner included in the first group, and ?s (C/m2) represents an absolute value of average surface charge density of the toner included in the second group.
    Type: Application
    Filed: August 6, 2019
    Publication date: February 20, 2020
    Inventors: Ryuji Murayama, Junichi Tamura, Kentaro Kamae, Hayato Ida, Daisuke Yamashita, Masaharu Miura, Takaho Shibata, Wakiko Katsumata, Yuichi Mizo
  • Patent number: 10514624
    Abstract: A toner comprising: a toner particle that contains a resin component and a silicone compound, wherein the resin component contains at least 50 mass % of olefin resin; a content of the silicone compound is from 1 mass part to 42 mass parts per 100 mass parts of the resin component; a weight-average molecular weight of the silicone compound as measured by GPC is from 1,000 to 25,000; and a content, in a molecular weight distribution of the silicone compound as measured by GPC, of a component having a weight-average molecular weight of not more than 500 is not more than 0.05 mass % of the silicone compound.
    Type: Grant
    Filed: October 1, 2018
    Date of Patent: December 24, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Junichi Tamura, Hayato Ida, Kentaro Kamae, Ryuji Murayama, Takashi Hirasa
  • Patent number: 10451990
    Abstract: A toner comprising a toner particle including a resin component, wherein the resin component includes an olefin copolymer including ester group having specific structures Y1 and Y2 and an olefin copolymer including acid group having an acid value of from 50 mg KOH/g to 300 mg KOH/g, the amount of the olefin copolymer including ester group is 50% by mass or more, the toner particle has a surface layer including the olefin copolymer including acid group which has formed a salt with a metal, the metal is at least one metal selected from the group consisting of Mg, Ca, Sr, Al, and Zn, and the total amount of the metal in the toner is from 25 ppm to 500 ppm.
    Type: Grant
    Filed: September 20, 2018
    Date of Patent: October 22, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kentaro Kamae, Ryuji Murayama, Junichi Tamura, Hayato Ida, Takashi Hirasa
  • Patent number: 10353312
    Abstract: A toner including a toner particle having a core-shell structure that has a core formed from a resin 1 and a shell formed from a resin 2 on the surface of the core, wherein the resin 1 contains more than 50 mass % of an ester group-containing olefin-based copolymer, the ester group-containing olefin-based copolymer has a monomer unit Y1 represented by formula (1) below, and at least one type of monomer unit Y2 selected from the group consisting of monomer units represented by formula (2) and formula (3) below, the ester group concentration in the ester group-containing olefin-based copolymer is from 2 mass % to 18 mass %, and the resin 2 is an amorphous resin having a Tg value of from 50° C. to 70° C.
    Type: Grant
    Filed: August 7, 2018
    Date of Patent: July 16, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kentaro Kamae, Ryuji Murayama, Junichi Tamura, Hayato Ida, Takashi Hirasa
  • Publication number: 20190113858
    Abstract: A toner comprising a toner particle including a resin component, wherein the resin component includes an olefin copolymer including ester group having specific structures Y1 and Y2 and an olefin copolymer including acid group having an acid value of from 50 mg KOH/g to 300 mg KOH/g, the amount of the olefin copolymer including ester group is 50% by mass or more, the toner particle has a surface layer including the olefin copolymer including acid group which has formed a salt with a metal, the metal is at least one metal selected from the group consisting of Mg, Ca, Sr, Al, and Zn, and the total amount of the metal in the toner is from 25 ppm to 500 ppm.
    Type: Application
    Filed: September 20, 2018
    Publication date: April 18, 2019
    Inventors: Kentaro Kamae, Ryuji Murayama, Junichi Tamura, Hayato Ida, Takashi Hirasa