Patents by Inventor Takaki KAWAMURA

Takaki KAWAMURA 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: 11860570
    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: Grant
    Filed: June 7, 2021
    Date of Patent: January 2, 2024
    Assignee: KONICA MINOLTA, INC.
    Inventors: Hiroshi Nagasawa, Yusuke Takigaura, Takaki Kawamura, Ami Motohashi, Natsuki Ito, Shiro Hirano
  • Patent number: 11312865
    Abstract: An object of the present invention is to provide an image forming method capable of coating a photocurable varnish without unevenness on a toner image formed using an electrostatic latent image developing toner, and further having good adhesion between a varnish layer and the toner image. The image forming method of the present invention comprises: forming a toner image on a recording medium using an electrostatic latent image developing toner containing a toner particle comprising a binder resin and a release agent; and forming a varnish layer on the toner image by applying and curing a photocurable varnish comprising a photocurable compound. The binder resin comprised in the electrostatic latent image developing toner contains a crystalline polyester resin. The photocurable compound comprised in the photocurable varnish comprises a diol di(meth)acrylate having a straight hydrocarbon chain.
    Type: Grant
    Filed: September 3, 2020
    Date of Patent: April 26, 2022
    Assignee: KONICA MINOLTA, INC.
    Inventors: Takaki Kawamura, Noboru Ueda, Natsuki Ito, Yusuke Takigaura, Ami Motohashi
  • 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
  • Publication number: 20210095134
    Abstract: An object of the present invention is to provide an image forming method capable of coating a photocurable varnish without unevenness on a toner image formed using an electrostatic latent image developing toner, and further having good adhesion between a varnish layer and the toner image. The image forming method of the present invention comprises: forming a toner image on a recording medium using an electrostatic latent image developing toner containing a toner particle comprising a binder resin and a release agent; and forming a varnish layer on the toner image by applying and curing a photocurable varnish comprising a photocurable compound. The binder resin comprised in the electrostatic latent image developing toner contains a crystalline polyester resin. The photocurable compound comprised in the photocurable varnish comprises a diol di(meth)acrylate having a straight hydrocarbon chain.
    Type: Application
    Filed: September 3, 2020
    Publication date: April 1, 2021
    Inventors: Takaki Kawamura, Noboru Ueda, Natsuki Ito, Yusuke Takigaura, Ami Motohashi
  • Publication number: 20210063905
    Abstract: An electrostatic latent image developing toner set of the present invention is an electrostatic latent image developing toner set including at least a yellow toner, a magenta toner, and a cyan toner, wherein when exothermic peak top temperatures during decreasing temperature in differential scanning calorimetry of the yellow toner, the magenta toner, and the cyan toner are assumed to be P(Y), P(M), and P(C), respectively, the exothermic peak top temperatures satisfy the following expression (1). 70?P(Y)?P(M)?P(C)?90(° C.
    Type: Application
    Filed: August 14, 2020
    Publication date: March 4, 2021
    Inventors: Takaki KAWAMURA, Noboru UEDA, Natsuki ITO, Yusuke TAKIGAURA, Ami MOTOHASHI
  • Publication number: 20200379365
    Abstract: An object of the present invention is to provide a new electrostatic latent image developing toner capable of suppressing adhesiveness of a release agent to a member such as a roller or the like and capable of suppressing gloss unevenness and gloss memory. An electrostatic latent image developing toner containing a binder resin, a release agent, and a colorant, wherein the binder resin contains a crystalline resin, the release agent contains a hydrocarbon wax having a branching degree of 3 to 52%, and a top temperature of an exothermic peak during cooling of the electrostatic latent image developing toner measured by a differential scanning calorimetry is within a range of 60 to 85° C.
    Type: Application
    Filed: May 27, 2020
    Publication date: December 3, 2020
    Inventors: Aya SHIRAI, Noboru UEDA, Takaki KAWAMURA, Yusuke TAKIGAURA, Natsuki ITO, Ami MOTOHASHI
  • Publication number: 20200379364
    Abstract: Provided is an electrostatic latent image developing toner capable of preventing a release agent from adhering to a member such as a paper conveying roller or the like. An electrostatic latent image developing toner contains at least a binder resin, a colorant, and a release agent, wherein the release agent contains at least an ester wax and the ester wax is an ester wax having a total carbon number of 45 or more and 71 or less, and a top temperature of an exothermic peak during cooling of the electrostatic latent image developing toner measured by a differential scanning calorimetry is within a range of 60° C. or higher and 85° C. or lower.
    Type: Application
    Filed: May 27, 2020
    Publication date: December 3, 2020
    Inventors: Noboru UEDA, Aya SHIRAI, Takaki KAWAMURA, Natsuki ITO, Yusuke TAKIGAURA, Ami MOTOHASHI
  • 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: 10627733
    Abstract: Provided is an image forming method using an electrostatic image developing toner containing: toner mother particles including a binder resin; and an external additive, wherein the binder resin contains a vinyl resin in an amount of 40 mass % or more with respect to the total amount of the binder resin, the image forming method including a step of: forming an image so that an image surface resistance value at 70° C. by a temperature change method of the formed image is set to be 5×1013 ? or less.
    Type: Grant
    Filed: October 17, 2018
    Date of Patent: April 21, 2020
    Assignee: KONICA MINOLTA, INC.
    Inventors: Tatsuya Fujisaki, Ami Motohashi, Takaki Kawamura
  • 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: 20190187577
    Abstract: Provided is an image forming method using an electrostatic image developing toner containing: toner mother particles including a binder resin; and an external additive, wherein the binder resin contains a vinyl resin in an amount of 40 mass % or more with respect to the total amount of the binder resin, the image forming method including a step of: forming an image so that an image surface resistance value at 70° C. by a temperature change method of the formed image is set to be 5×1013 ? or less.
    Type: Application
    Filed: October 17, 2018
    Publication date: June 20, 2019
    Inventors: Tatsuya FUJISAKI, Ami MOTOHASHI, Takaki KAWAMURA
  • 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: 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: 9983495
    Abstract: An electrostatic image developing toner including a toner particle, wherein the toner particle contains a vinyl resin which is a polymer of a vinyl monomer having an acid group, a polyester resin, at least one of aluminum (Al) and magnesium (Mg), and tin (Sn), and when net intensities of Al, Mg and Sn in the toner particle measured by fluorescent X-ray analysis are respectively expressed as IAl, IMg and ISn, a ratio (IAl+IMg)/ISn is within a range of 0.5 to 2.5.
    Type: Grant
    Filed: September 28, 2016
    Date of Patent: May 29, 2018
    Assignee: KONICA MINOLTA, INC.
    Inventors: Junya Ueda, Kenshi Miyajima, Takaki Kawamura
  • 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: 9915883
    Abstract: The toner of the present invention is an electrostatic latent image developing toner, and has a toner base particle. The toner base particle contains a binder resin including a crystalline resin, and a release agent. The toner has the maximum value G?MAX at a temperature equal to or lower than Tm, among specific storage elastic modulus ratios, of 2.2 or more. The Tm represents a peak top temperature (° C.) of a specific endothermic peak in DSC of the toner.
    Type: Grant
    Filed: September 22, 2016
    Date of Patent: March 13, 2018
    Assignee: KONICA MINOLTA, INC.
    Inventors: Takaki Kawamura, Kenshi Miyajima, Junya Ueda
  • Patent number: 9897935
    Abstract: An image forming method forms a color toner image and a white toner image using an image forming apparatus having a plurality of developing machines. The color toner image is formed using a color developer containing a first carrier and at least one color toner selected from a yellow toner, a magenta toner, and a cyan toner. The white toner image is formed using a white developer containing a second carrier and a white toner containing at least titanium oxide as a pigment. Formula (1): Iw<Ic??(1) is satisfied. Ic (?A) is a dynamic current value of the first carrier at 100 V and Iw (?A) is a dynamic current value of the second carrier at 100 V.
    Type: Grant
    Filed: March 8, 2016
    Date of Patent: February 20, 2018
    Assignee: KONICA MINOLTA, INC.
    Inventors: Yasuko Uchino, Junya Onishi, Natsuko Fujisaki, Anju Hori, Junya Ueda, Takaki Kawamura, Ikuko Sakurada
  • Publication number: 20170242358
    Abstract: The toner of the present invention is an electrostatic latent image developing toner, and has a toner base particle. The toner base particle contains a binder resin including a crystalline resin, and a release agent. The toner has the maximum value G?MAX at a temperature equal to or lower than Tm, among specific storage elastic modulus ratios, of 2.2 or more. The Tm represents a peak top temperature (° C.) of a specific endothermic peak in DSC of the toner.
    Type: Application
    Filed: September 22, 2016
    Publication date: August 24, 2017
    Inventors: Takaki KAWAMURA, Kenshi MIYAJIMA, Junya UEDA
  • Patent number: 9740122
    Abstract: The present toner is an electrostatic latent image developing toner, and contains a toner base particle. The toner base particle contains a binder resin and a release agent. The binder resin contains a crystalline resin and a vinyl resin. When the storage elastic modulus G? at 50° C. is defined as G?50° C., the peak top temperature (° C.) of a specific endothermic peak in DSC of the toner is defined as Tm, the measurement temperature (° C.) at a G? of 1×106 Pa is defined as TmA, and the measurement temperature (° C.) at a G? of 1×105 Pa is defined as TmB, the toner satisfies the following expressions (1) to (3): G?50° C.?1×108??(1) TmB?TmA?8??(2) Tm<TmB??(3).
    Type: Grant
    Filed: September 22, 2016
    Date of Patent: August 22, 2017
    Assignee: KONICA MINOLTA, INC.
    Inventors: Takaki Kawamura, Aya Shirai, Kaori Fujino