Patents by Inventor Norifumi Itako

Norifumi Itako 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: 11754936
    Abstract: Provided is a wax which is used in a toner, whereby the toner is excellent in low-temperature fixability and heat-resistant shelf stability, the glossiness is improved as compared with the prior art, and the generation of ultrafine particles and the bleeding of the wax are not likely to occur. The wax for toners, wherein the wax is an ester wax generated by esterification of a pentaerythritol and a monocarboxylic acid; wherein the monocarboxylic acid used for the esterification contains a behenic acid, an arachidic acid and a stearic acid; and wherein, with respect to 100% by mass of the monocarboxylic acid, a content ratio of the behenic acid is from 60% by mass to 80% by mass; a content ratio of the arachidic acid is from 5% by mass to 15% by mass; and a content ratio of the stearic acid is from 15% by mass to 25% by mass.
    Type: Grant
    Filed: October 7, 2019
    Date of Patent: September 12, 2023
    Assignees: ZEON CORPORATION, NOF CORPORATION
    Inventors: Masashi Watanabe, Takeshi Yoshimura, Norifumi Itako
  • Publication number: 20210341852
    Abstract: Provided is a wax which is used in a toner, whereby the toner is excellent in low-temperature fixability and heat-resistant shelf stability, the glossiness is improved as compared with the prior art, and the generation of ultrafine particles and the bleeding of the wax are not likely to occur. The wax for toners, wherein the wax is an ester wax generated by esterification of a pentaerythritol and a monocarboxylic acid; wherein the monocarboxylic acid used for the esterification contains a behenic acid, an arachidic acid and a stearic acid; and wherein, with respect to 100% by mass of the monocarboxylic acid, a content ratio of the behenic acid is from 60% by mass to 80% by mass; a content ratio of the arachidic acid is from 5% by mass to 15% by mass; and a content ratio of the stearic acid is from 15% by mass to 25% by mass.
    Type: Application
    Filed: October 7, 2019
    Publication date: November 4, 2021
    Applicants: ZEON CORPORATION, NOF CORPORATION
    Inventors: Masashi Watanabe, Takeshi Yoshimura, Norifumi Itako
  • Patent number: 10503089
    Abstract: There is provided a toner for developing electrostatic images, including an external additive and colored resin particles containing a binder resin, a colorant and softening agents. The colored resin particles contain a monoester compound A represented by formula (1) and a monoester compound B represented by formula (2) as softening agents. A content of the monoester compound A is in the range from 95 to 99% by mass, a content of the monoester compound B is in the range from 1 to 5% by mass, and a content of the softening agents is in the range from 10 to 30 parts by mass, with respect to 100 parts by mass of the binder resin. Formula (1) is R1—COO—R2. Formula (2) is R3—COO—R4.
    Type: Grant
    Filed: March 26, 2014
    Date of Patent: December 10, 2019
    Assignees: ZEON CORPORATION, NOF CORPORATION
    Inventors: Azusa Masuda, Ryuji Ohta, Munehiro Yamada, Norifumi Itako, Ryosuke Uemura
  • Publication number: 20160048090
    Abstract: There is provided a toner for developing electrostatic images, including an external additive and colored resin particles containing a binder resin, a colorant and softening agents. The colored resin particles contain a monoester compound A represented by formula (1) and a monoester compound B represented by formula (2) as softening agents. A content of the monoester compound A is in the range from 95 to 99% by mass, a content of the monoester compound B is in the range from 1 to 5% by mass, and a content of the softening agents is in the range from 10 to 30 parts by mass, with respect to 100 parts by mass of the binder resin. Formula (1) is R1—COO—R2. Formula (2) is R3—COO—R4.
    Type: Application
    Filed: March 26, 2014
    Publication date: February 18, 2016
    Applicants: ZEON CORPORATION, NOF CORPORATION
    Inventors: Azusa Masuda, Ryuji Ohta, Munehiro Yamada, Norifumi Itako, Ryosuke Uemura