Patents by Inventor Koh lshigami

Koh lshigami 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: 20210302854
    Abstract: A toner comprising a toner particle containing a binder resin containing at least 50 mass % of a polyester resin, wherein the polyester resin contains a polyester resin A having a silicone segment, and in XPS analysis, when X is a ratio of the number of silicon atoms attributable to silicone segments relative to a total number of measured atoms, X1 is a value of the X on the toner particle surface, X2 is a value of the X at a depth of 30 nm from the surface, Z is a ratio of the number of carbon atoms attributable to ester bonds relative to a total number of measured atoms, Z1 is a value of the Z on the toner particle surface and Z2 is a value of the Z at a depth of 30 nm from the toner particle surface, X1, Z1, X2 and Z2 satisfy a specific relationship.
    Type: Application
    Filed: March 24, 2021
    Publication date: September 30, 2021
    Inventors: Shin Kitamura, Nobuyoshi Sugahara, Daisuke Tsujimoto, Kazunari Ooyama, Yuu Nishimura, Kazuki Murata, Toru Takahashi, Ryo Nakajima, Hitoshi Sano, Koh lshigami, Takaho Shibata
  • Publication number: 20210286282
    Abstract: The present invention provides a white toner which has high charge uniformity and enables stable print-out of high-quality images irrespective of its usage environment. The above object can be solved by a white toner including a white toner particle containing a binder resin, a white pigment and an inorganic fine particle, in which the white pigment has a work function of 5.80 eV or more and 6.10 eV or less, the content of the white pigment is 15.0 parts by mass or more and 60.0 parts by mass or less relative to 100 parts by mass of the binder resin, and the inorganic fine particle has a work function of 6.15 eV or more.
    Type: Application
    Filed: May 28, 2021
    Publication date: September 16, 2021
    Inventors: Takakuni Kobori, Kenta Mitsuiki, Hitoshi Sano, Wakiko Katsumata, Daisuke Yamashita, Yosuke Iwasaki, Takeshi Ohtsu, Takaho Shibata, Masaharu Miura, Koh lshigami, Yuichi Mizo
  • Publication number: 20180059565
    Abstract: A toner having a toner particle containing an amorphous resin, a crystalline resin, a colorant, a release agent, and a polymer in which a styrene-acrylic polymer is graft-polymerized on a polyolefin, wherein the amorphous resin contains an amorphous polyester resin A, and the amorphous polyester resin A has a monomer unit derived from polyhydric alcohol and a monomer unit derived from polyhydric carboxylic acid, has, a particular amount of a succinic acid-derived monomer unit in the monomer unit derived from polyhydric carboxylic acid, and has, a particular amount of a monomer unit derived from a propylene oxide adduct on bisphenol A in the monomer unit derived from polyhydric alcohol; and has a particular softening point, a particular solubility parameter, and a particular peak molecular weight.
    Type: Application
    Filed: August 21, 2017
    Publication date: March 1, 2018
    Inventors: Kentaro Kamae, Ryuichiro Matsuo, Yosuke Iwasaki, Wakiko Katsumata, Kenta Mitsuiki, Takeshi Ohtsu, Masaharu Miura, Koh lshigami, Yuichi Mizo
  • Publication number: 20180052402
    Abstract: A toner production method including: a melt-kneading step of melt-kneading a resin composition including a binder resin, a colorant, a wax, and a wax dispersant to obtain a melt-kneaded product; and a pulverizing step of pulverizing the melt-kneaded product. Where the temperature of the melt-kneaded product at the end of the melt-kneading step is Tk(° C.), and the softening point of the wax dispersant is Tm(° C.), the relationship of ?18?[Tk?Tm]?10 is satisfied. The wax dispersant is a polymer in which a styrene acrylic polymer is graft-polymerized to a polyolefin. The styrene acrylic polymer has a monomer unit derived from ?-methylstyrene and a monomer unit derived from a cycloalkyl (meth)acrylate.
    Type: Application
    Filed: August 10, 2017
    Publication date: February 22, 2018
    Inventors: Yosuke Iwasaki, Takeshi Ohtsu, Kentaro Kamae, Ryuichiro Matsuo, Wakiko Katsumata, Kenta Mitsuiki, Masaharu Miura, Koh lshigami, Yuichi Mizo