Patents by Inventor Masayuki UKIGAYA

Masayuki UKIGAYA 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: 20220155699
    Abstract: A toner is provided. The toner comprises toner particles each comprising a toner base particle and an external additive. The toner base particle comprises a binder resin and a colorant. The toner satisfies the following conditions (a) and (b): (a) an average surface roughness Ra [nm] of the toner particles, detected by a scanning probe microscope analyzer, satisfies the following formula (1): 10<Ra<200??Formula (1); and (b) the external additive comprises coalesced particles being non-spherical secondary particles in which primary particles are coalesced with each other, the coalesced particles having a number average particle diameter of 50 nm or more.
    Type: Application
    Filed: October 14, 2021
    Publication date: May 19, 2022
    Applicant: Ricoh Company, Ltd.
    Inventors: Yohichi KITAGAWA, Kenji Komito, Masayuki Ukigaya, Mitsuaki Hirose, Daisuke Inoue
  • Publication number: 20220057725
    Abstract: A toner is provided. The toner comprises toner base particles, resin particles adhered to surfaces of the toner base particles, and an external additive adhered to the surfaces of the toner base particles. The toner base particles each comprising a binder resin, a colorant, and a wax. The toner has a storage elastic modulus G? of 4.0×105 or less at 70° C. An embedment degree of the external additive is from 15% to 40%, as the embedment degree is measured by stirring 10 g of the toner and 20 g of a carrier in a 50-mL vial at 67 Hz for 60 minutes using a rocking mill.
    Type: Application
    Filed: August 16, 2021
    Publication date: February 24, 2022
    Applicant: Ricoh Company, Ltd.
    Inventors: Daisuke INOUE, Mitsuaki Hirose, Yohichi Kitagawa, Masayuki Ukigaya, Kenji Komito, Hiroshi Yamada
  • Patent number: 11036154
    Abstract: A toner is provided. The toner comprises a colorant, a release agent, and a binder resin. The binder resin comprises a crystalline polyester resin and an amorphous polyester resin. The amorphous polyester resin comprises an amorphous polyester resin A and an amorphous polyester resin B. The amorphous polyester resin A comprises an isocyanurate backbone and at least one of urethane bond and urea bond. The amorphous polyester resin B comprises a trimellitic acid backbone and at least one of urethane bond and urea bond.
    Type: Grant
    Filed: November 26, 2018
    Date of Patent: June 15, 2021
    Assignee: Ricoh Company, Ltd.
    Inventors: Masayuki Ukigaya, Junichi Awamura, Hiroshi Yamada, Kohsuke Nagata, Hiroyuki Takeda
  • Publication number: 20190171122
    Abstract: A toner is provided. The toner comprises a colorant, a release agent, and a binder resin. The binder resin comprises a crystalline polyester resin and an amorphous polyester resin. The amorphous polyester resin comprises an amorphous polyester resin A and an amorphous polyester resin B. The amorphous polyester resin A comprises an isocyanurate backbone and at least one of urethane bond and urea bond. The amorphous polyester resin B comprises a trimellitic acid backbone and at least one of urethane bond and urea bond.
    Type: Application
    Filed: November 26, 2018
    Publication date: June 6, 2019
    Inventors: Masayuki UKIGAYA, Junichi AWAMURA, Hiroshi YAMADA, Kohsuke NAGATA, Hiroyuki TAKEDA