Patents by Inventor Shiro Hirano

Shiro Hirano 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: 20220011687
    Abstract: The toner for developing an electrostatic charge image of the present invention contains a toner base particle comprising a binder resin and at least two kinds of organic pigments, and alumina as an external additive. The at least two kinds of organic pigments comprises: a pigment P1 having an absorption maximum wavelength ?max (nm) of greater than 400 nm and less than 600 nm when dispersed in methyl ethyl ketone; and a pigment P2 having an absorption maximum wavelength ? max (nm) of 600 nm or more and 700 nm or less when dispersed in methyl ethyl ketone.
    Type: Application
    Filed: July 9, 2021
    Publication date: January 13, 2022
    Inventors: Shiro HIRANO, Takanari KAYAMORI, Yuya KUBO
  • Publication number: 20220011686
    Abstract: The toner for developing an electrostatic charge image of the present invention contains a toner base particle comprising a binder resin and at least two kinds of organic pigments, and strontium titanate as an external additive.
    Type: Application
    Filed: July 9, 2021
    Publication date: January 13, 2022
    Inventors: Takanari KAYAMORI, Yuya KUBO, Shiro HIRANO
  • Publication number: 20220004113
    Abstract: A toner set includes a plurality of toners, wherein the toner set includes a first toner containing a yellow colorant and a second toner containing a cyan colorant, the first toner and the second toner each contain a binder resin containing a vinyl-based resin and a crystalline resin, and a release agent containing a hydrocarbon wax, a content of the vinyl-based resin with respect to a total mass of the binder resin is 50% by mass or more, the first toner contains the crystalline resin having a moiety having a crystal structure and a crystal nucleating agent moiety having a crystal nucleating agent, and the second toner contains the cyan colorant that is a compound represented by general formula (1).
    Type: Application
    Filed: June 7, 2021
    Publication date: January 6, 2022
    Inventors: Hiroshi NAGASAWA, Yusuke TAKIGAURA, Takaki KAWAMURA, Ami MOTOHASHI, Natsuki ITO, Shiro HIRANO
  • Patent number: 11156933
    Abstract: Provided is an image forming method, including: transferring and fixing a toner onto a recording medium, and forming an image including a plurality of layers, in which an attachment amount of the toner on the recording medium is greater than or equal to 8 g/m2 and less than or equal to 40 g/m2, a toner forming a layer in contact with a fixing member contains at least a first mold release agent containing ester wax and a second mold release agent containing microcrystalline wax, and a special color toner is contained in any layer of the plurality of layers.
    Type: Grant
    Filed: April 21, 2020
    Date of Patent: October 26, 2021
    Assignee: KONICA MINOLTA, INC.
    Inventors: Keisuke Asano, Shiro Hirano, Kazuhiko Nakajima
  • Publication number: 20200356020
    Abstract: Provided is an image forming method, including: transferring and fixing a toner onto a recording medium, and forming an image including a plurality of layers, in which an attachment amount of the toner on the recording medium is greater than or equal to 8 g/m2 and less than or equal to 40 g/m2, a toner forming a layer in contact with a fixing member contains at least a first mold release agent containing ester wax and a second mold release agent containing microcrystalline wax, and a special color toner is contained in any layer of the plurality of layers.
    Type: Application
    Filed: April 21, 2020
    Publication date: November 12, 2020
    Inventors: Keisuke ASANO, Shiro HIRANO, Kazuhiko NAKAJIMA
  • Patent number: 10698328
    Abstract: Provided is an electrostatic image developing toner including: toner mother particles containing a binder resin and a releasing agent; and an external additive, wherein the binder resin contains a crystalline resin, and the electrostatic image developing toner satisfies the following formulas (1) and (2), tan ?3° C./min<tan ?6° C./min??Formula (1): 0.0005?tan ?6° C./min?tan ?3° C./min,??Formula (2): wherein: tan ?6° C./min is a peak top value of a loss tangent when the loss tangent is measured from 25° C. to 100° C. at a frequency of 1 Hz and a heating rate of 6° C./min; and tan ?3° C./min is a peak top value of a loss tangent when the loss tangent is measured from 25° C. to 100° C. at a frequency of 1 Hz and a heating rate of 3° C./min.
    Type: Grant
    Filed: December 28, 2018
    Date of Patent: June 30, 2020
    Assignee: KONICA MINOLTA, INC.
    Inventors: Takaki Kawamura, Shiro Hirano, Junya Onishi, Ami Motohashi
  • Patent number: 10627734
    Abstract: In an image forming method according to the present invention, an image is formed by removing residual charge from the image on an image recording medium. The image forming method includes formation of an image for forming a toner image by fixing a toner on the image recording medium and application of voltage from a voltage applier, the voltage having a polarity reverse to a polarity of a surface potential of the toner image. The toner includes toner base particles and an external additive. The toner base particles include a crystalline polyester resin.
    Type: Grant
    Filed: November 9, 2018
    Date of Patent: April 21, 2020
    Assignee: KONICA MINOLTA, INC.
    Inventors: Junya Onishi, Kentarou Mogi, Ami Motohashi, Shiro Hirano
  • Publication number: 20190258185
    Abstract: Provided is an electrostatic image developing toner including: toner mother particles containing a binder resin and a releasing agent; and an external additive, wherein the binder resin contains a crystalline resin, and the electrostatic image developing toner satisfies the following formulas (1) and (2), tan ?3° C./min<tan ?6° C./min??Formula (1): 0.0005?tan ?6° C./min?tan ?3° C./min,??Formula (2): wherein: tan ?6° C./min is a peak top value of a loss tangent when the loss tangent is measured from 25° C. to 100° C. at a frequency of 1 Hz and a heating rate of 6° C./min; and tan ?3° C./min is a peak top value of a loss tangent when the loss tangent is measured from 25° C. to 100° C. at a frequency of 1 Hz and a heating rate of 3° C./min.
    Type: Application
    Filed: December 28, 2018
    Publication date: August 22, 2019
    Inventors: Takaki KAWAMURA, Shiro HIRANO, Junya ONISHI, Ami MOTOHASHI
  • Publication number: 20190163095
    Abstract: In an image forming method according to the present invention, an image is formed by removing residual charge from the image on an image recording medium. The image forming method includes formation of an image for forming a toner image by fixing a toner on the image recording medium and application of voltage from a voltage applier, the voltage having a polarity reverse to a polarity of a surface potential of the toner image. The toner includes toner base particles and an external additive. The toner base particles include a crystalline polyester resin.
    Type: Application
    Filed: November 9, 2018
    Publication date: May 30, 2019
    Inventors: Junya ONISHI, Kentarou MOGI, Ami MOTOHASHI, Shiro HIRANO
  • Patent number: 10254672
    Abstract: Provided is a means to exhibit excellent low temperature fixability and to improve all of the heat-resistant storage property of a toner, charging uniformity, and transferability under a high temperature and high humidity condition. A toner for developing electrostatic charge image which contains at least a binder resin, in which the binder resin has a core-shell structure having a core portion which contains a hybrid crystalline polyester resin formed by chemical bonds of a crystalline polyester resin unit with an amorphous resin unit other than a polyester resin and an amorphous resin and a shell portion which contains a hybrid amorphous polyester resin formed by chemical bonds of an amorphous polyester resin unit with an amorphous resin unit other than a polyester resin.
    Type: Grant
    Filed: February 23, 2016
    Date of Patent: April 9, 2019
    Assignee: KONICA MINOLTA, INC
    Inventors: Noboru Ueda, Shiro Hirano
  • Patent number: 10203618
    Abstract: An electrostatic charge image developing toner includes a binder resin and a release agent. A ratio of a crystalline polyester resin to the total amount of a amorphous polyester resin and the crystalline polyester resin is within a range exceeding 40% by mass to 60% by mass. A temperature at which a storage modulus before heat left G? before being left to stand at a temperature of X° C. becomes 1.0×108 Pa is within a range exceeding 45° C. to 55° C. A storage modulus after heat left G? at a temperature of X?° C. at which a value of a ratio of the storage modulus after heat left G? at a temperature of X° C. after being left to stand at the temperature of X° C. for 2 hours to the storage modulus before heat left G? at the temperature of X° C. becomes the maximum is within a range of 1.0×108 to 5.0×108 Pa.
    Type: Grant
    Filed: January 26, 2018
    Date of Patent: February 12, 2019
    Assignee: KONICA MINOLTA, INC.
    Inventors: Yusuke Takigaura, Takaki Kawamura, Shiro Hirano
  • Patent number: 10126668
    Abstract: A toner for electrostatic charge image development contains a binder resin and a releasing agent. The binder resin contains an amorphous polyester resin as a main component and a vinyl resin, the vinyl resin contains a constitutional unit derived from a specific monomer. The releasing agent has a melting point of from 65 to 90° C. and contains an ester wax.
    Type: Grant
    Filed: August 31, 2017
    Date of Patent: November 13, 2018
    Assignee: Konica Minolta, Inc.
    Inventors: Kouji Sugama, Shiro Hirano, Noboru Ueda, Kaori Matsushima
  • Patent number: 10120296
    Abstract: An electrostatic latent image developing toner includes toner particles which comprises a binder resin and a releasing agent. A main component of the binder resin is a polyester resin. The binder resin comprises a crystalline polyester resin, an amorphous polyester resin and a hybrid vinyl resin. The hybrid vinyl resin is composed of a vinyl polymer segment and at least one segment selected from a polyester polymer segment, an urethane polymer segment and an urea polymer segment which is chemically bound to the vinyl polymer segment. A main component of the hybrid vinyl resin is the vinyl polymer segment which comprises a structural unit derived from a monomer having a specific structure. A tetrahydrofuran-soluble fraction of the toner has a main peak of a molecular weight distribution measured by gel permeation chromatography within the range of 11000 to 30000.
    Type: Grant
    Filed: September 20, 2017
    Date of Patent: November 6, 2018
    Assignee: KONICA MINOLTA, INC.
    Inventors: Kaori Matsushima, Noboru Ueda, Shiro Hirano, Kouji Sugama
  • Patent number: 10078283
    Abstract: Provided is a toner for developing electrostatic images containing a toner particle. The toner particle contains a binder resin and a release agent. The binder resin contains a vinyl resin component and a crystalline polyester resin component. The vinyl resin component has a structural unit derived from an alkyl (meth)acrylate monomer represented by Formula (1): H2C?CR1—COOR2 ??Formula (1): In Formula (1), R1 represents a hydrogen atom or a methyl group, and R2 represents an alkyl group having 8 to 22 carbon atoms. The crystalline polyester resin component satisfies Formula (2): 5?|Cacid?Calcohol|?12 ??Formula (2): In Formula (2), Calcohol represents the number of carbon atoms of the main chain of a structural unit derived from a polyhydric alcohol and Cacid represents the number of carbon atoms of the main chain of a structural unit derived from a polyvalent carboxylic acid.
    Type: Grant
    Filed: July 14, 2016
    Date of Patent: September 18, 2018
    Assignee: KONICA MINOLTA, INC.
    Inventors: Aya Shirai, Shiro Hirano, Junya Onishi
  • Patent number: 10067435
    Abstract: An electrostatic charge image developing toner includes a particulate toner matrix containing a binder resin and an external additive. The binder resin includes an amorphous polyester resin, a crystalline resin, and an amorphous vinyl resin. A storage modulus G?0(t) measured before the toner is left and storage moduli G?Tm-10(t) and G?Tm-20(t) measured after the toner is left for three hours at temperatures (Tm-10)° C. and (Tm-20)° C., respectively, based on a melting point (Tm° C.) derived from the crystalline resin satisfy the relations represented by G?0(t)<G?Tm-10(t), G?0(t)<G?Tm-20(t), and G?Tm-10(x)/G?Tm-20(x)?1.5 in a temperature range A for measurement where the storage modulus G?0(t) is 1.0×106 Pa or more. The value t represents any temperature (° C.) for measurement in the temperature range A for measurement; and the value x represents the temperature (° C.) for measurement having a maximum difference between the storage moduli G?Tm-10(t) and G?Tm-20(t).
    Type: Grant
    Filed: October 18, 2017
    Date of Patent: September 4, 2018
    Assignee: KONICA MINOLTA, INC.
    Inventors: Takaki Kawamura, Shiro Hirano, Yusuke Takigaura
  • Publication number: 20180217515
    Abstract: An electrostatic charge image developing toner includes a binder resin and a release agent. A ratio of a crystalline polyester resin to the total amount of a amorphous polyester resin and the crystalline polyester resin is within a range exceeding 40% by mass to 60% by mass. A temperature at which a storage modulus before heat left G? before being left to stand at a temperature of X° C. becomes 1.0×108 Pa is within a range exceeding 45° C. to 55° C. A storage modulus after heat left G? at a temperature of X?° C. at which a value of a ratio of the storage modulus after heat left G? at a temperature of X° C. after being left to stand at the temperature of X° C. for 2 hours to the storage modulus before heat left G? at the temperature of X° C. becomes the maximum is within a range of 1.0×108 to 5.0×108 Pa.
    Type: Application
    Filed: January 26, 2018
    Publication date: August 2, 2018
    Inventors: Yusuke TAKIGAURA, Takaki KAWAMURA, Shiro HIRANO
  • Patent number: 9996017
    Abstract: An object of the present invention is to provide an electrostatic latent image developing toner containing: a binder resin; and a releasing agent, wherein the binder resin contains a crystalline polyester resin; an endothermic peak top temperature of the electrostatic latent image developing toner is 70° C. or more measured with differential scanning calorimetry (DSC) in a heating-up period of the toner; and a heat value ?Hc(L) is 15% or less with respect to a heat value ?Hc, wherein the heat value ?Hc(L) is a heat value in the range of (an exothermic peak top temperature rc?7° C.) or less; and the heat value ?Hc is a heat value of the total exothermic peak measured with DSC in a heating-down period of the toner.
    Type: Grant
    Filed: June 15, 2017
    Date of Patent: June 12, 2018
    Assignee: KONICA MINOLTA, INC.
    Inventors: Aya Shirai, Kouji Sugama, Shiro Hirano, Noboru Ueda
  • Patent number: 9983491
    Abstract: A process for producing a toner of the present invention includes: a first step of heating a dispersion containing an aqueous medium and a binder resin containing a crystalline resin to a temperature higher than or equal to a melting point of the crystalline resin; and a second step of maintaining the dispersion at temperature T (° C.) for 30 minutes or longer in a state where a pH of the dispersion is maintained at 5.5 or higher and 9.0 or lower, in which the temperature T satisfies the following expression, Rc?25?T?Rc?5, where the Rc represents a recrystallization temperature (° C.) of the crystalline resin.
    Type: Grant
    Filed: February 22, 2017
    Date of Patent: May 29, 2018
    Assignee: KONICA MINOLTA, INC.
    Inventors: Junya Onishi, Shiro Hirano, Noboru Ueda, Kouji Sugama, Aya Shirai
  • Publication number: 20180129146
    Abstract: An electrostatic charge image developing toner includes a particulate toner matrix containing a binder resin and an external additive. The binder resin includes an amorphous polyester resin, a crystalline resin, and an amorphous vinyl resin. A storage modulus G?0(t) measured before the toner is left and storage moduli G?Tm-10(t) and G?Tm-20(t) measured after the toner is left for three hours at temperatures (Tm-10)° C. and (Tm-20)° C., respectively, based on a melting point (Tm ° C.) derived from the crystalline resin satisfy the relations represented by G?0(t)<G?Tm-10(t), G?0(t)<G?Tm-20(t), and G?Tm-10(x)/G?Tm-20(x)?1.5 in a temperature range A for measurement where the storage modulus G?0(t) is 1.0×106 Pa or more. The value t represents any temperature (° C.) for measurement in the temperature range A for measurement; and the value x represents the temperature (° C.) for measurement having a maximum difference between the storage moduli G?Tm-10(t) and G?Tm-20(t).
    Type: Application
    Filed: October 18, 2017
    Publication date: May 10, 2018
    Inventors: Takaki KAWAMURA, Shiro Hirano, Yusuke Takigaura
  • Patent number: 9933716
    Abstract: The present invention relates to a toner for electrostatic charge image development, including toner base particles containing a binder resin containing as a main component a vinyl resin having a constitutional unit derived from a monomer having an acid group, and aluminum, wherein a concentration of the aluminum in the toner base particles, as measured by radio inductively coupled plasma emission spectral analysis, is from 900 to 2,200 ppm. According to the present invention, there is provided a means for improving the environmental stability of electrification, and the glossiness and the image density of the image to be formed in a good balance while maintaining sufficient low temperature fixability in a toner for electrostatic charge image development.
    Type: Grant
    Filed: September 28, 2016
    Date of Patent: April 3, 2018
    Assignee: KONICA MINOLTA, INC.
    Inventors: Shiro Hirano, Noboru Ueda, Kouji Sugama, Junya Onishi, Aya Shirai, Tatsuya Fujisaki