Patents by Inventor Hideki Gambayashi

Hideki Gambayashi 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: 10240054
    Abstract: Provided is a method for producing an aqueous pigment dispersion including a step of dispersing a mixture containing a pigment, an anionic group-containing organic polymer compound, a basic compound, and from 1% to 500% by mass of alkylene oxide adduct having a polyamine structure with respect to the pigment into water. The step of dispersing includes Step 1 of kneading a mixture which contains a pigment, an anionic group-containing organic polymer compound, a basic compound, and from 1% to 500% by mass of alkylene oxide adduct having a polyamine structure with respect to the pigment, and which contains no water or water equal to or less than 30% by mass with respect to a solid content thereof, and Step 2 of dispersing a kneaded material obtained in Step 1 into water.
    Type: Grant
    Filed: February 9, 2016
    Date of Patent: March 26, 2019
    Assignee: DIC CORPORATION
    Inventors: Ryota Hibino, Kumiko Iizasa, Hideki Gambayashi, Shinichi Okada
  • Publication number: 20180010005
    Abstract: Provided is a method for producing an aqueous pigment dispersion including a step of dispersing a mixture containing a pigment, an anionic group-containing organic polymer compound, a basic compound, and from 1% to 500% by mass of alkylene oxide adduct having a polyamine structure with respect to the pigment into water. The step of dispersing includes Step 1 of kneading a mixture which contains a pigment, an anionic group-containing organic polymer compound, a basic compound, and from 1% to 500% by mass of alkylene oxide adduct having a polyamine structure with respect to the pigment, and which contains no water or water equal to or less than 30% by mass with respect to a solid content thereof, and Step 2 of dispersing a kneaded material obtained in Step 1 into water.
    Type: Application
    Filed: February 9, 2016
    Publication date: January 11, 2018
    Applicant: DIC Corporation
    Inventors: Ryota Hibino, Kumiko Iizasa, Hideki Gambayashi, Shinichi Okada
  • Patent number: 6824943
    Abstract: The present invention provides a toner for electrostatic image development which employs a black colorant free from a toxic substance and exhibits stable charge behavior even after extended use or printing of a large number of sheets, thus making it possible to provide printed images having sufficient image density without causing toner dispersion, fogging, and variation in image density. This is a toner for electrostatic image development comprising a binder resin and a colorant, wherein the colorant is made of black fine particles obtained by coating the surface of titanium dioxide particles with a complex oxide of titanium and iron.
    Type: Grant
    Filed: February 25, 2003
    Date of Patent: November 30, 2004
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventor: Hideki Gambayashi
  • Publication number: 20030198882
    Abstract: The present invention provides a toner for electrostatic image development which employs a black colorant free from a toxic substance and exhibits stable charge behavior even after extended use or printing of a large number of sheets, thus making it possible to provide printed images having sufficient image density without causing toner dispersion, fogging, and variation in image density. This is a toner for electrostatic image development comprising a binder resin and a colorant, wherein the colorant is made of black fine particles obtained by coating the surface of titanium dioxide particles with a complex oxide of titanium and iron.
    Type: Application
    Filed: February 25, 2003
    Publication date: October 23, 2003
    Applicant: DAINIPPON INK AND CHEMICALS, INC.
    Inventor: Hideki Gambayashi
  • Patent number: 6534229
    Abstract: An object of the present invention is to provide a developer for electrostatic image development, which exhibits stable charge behavior during printing even when using a polyester resin and does not cause contamination of the inside of the apparatus because of less scattering of the toner, and also facilitates easy maintenance. The developer for electrostatic image development of the present invention comprises colored resin particles comprising at least a binder resin and a colorant, and a magnetic carrier, wherein a proportion of said colored resin particles having a particle diameter in a range of from 12 &mgr;m to 16 &mgr;m, inclusive, in said developer and a specific charge amount of said colored resin particles meet the following expression (1): 5.18+0.
    Type: Grant
    Filed: February 12, 2001
    Date of Patent: March 18, 2003
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Katsunori Ohba, Katsuyuki Ogura, Masanobu Nakamura, Toshiro Kogawara, Hideki Gambayashi
  • Patent number: 6335139
    Abstract: The present invention provides a toner for electrostatic image development which reconciles anti-offset properties and fixation properties and is superior in resistance to abrasion and peel of the fixed image in uses where the development and fixation are conducted at a wide range of a fixing speed, particularly high speed which exceeds 20 or 30 m/min. The toner comprises a polyester resin, a colorant, and a releasing agent, wherein the flow beginning temperature Tfb of the toner as measured by a constant load extrusion type capillary rheometer is within a range of 70-105° C. and the flow ending temperature Tend is within a range of 120-144° C.
    Type: Grant
    Filed: August 22, 2000
    Date of Patent: January 1, 2002
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Hideki Gambayashi, Masanobu Nakamura, Toshiro Kogawara, Shinji Amaya
  • Publication number: 20010019805
    Abstract: An object of the present invention is to provide a developer for electrostatic image development, which exhibits stable charge behavior during printing even when using a polyester resin and does not cause contamination of the inside of the apparatus because of less scattering of the toner, and also facilitates easy maintenance.
    Type: Application
    Filed: February 12, 2001
    Publication date: September 6, 2001
    Applicant: DAINIPPON INK AND CHEMICALS, INC.
    Inventors: Katsunori Ohba, Katsuyuki Ogura, Masanobu Nakamura, Toshiro Kogawara, Hideki Gambayashi
  • Patent number: 6238836
    Abstract: An electrostatic image developer is provided which has superior fixation properties and anti-offset properties, exhibits stable charge behavior even during continuous printing, and has superior durability and permits a high-quality image to be obtained.
    Type: Grant
    Filed: September 22, 1999
    Date of Patent: May 29, 2001
    Assignee: Dainippon Ink Chemicals, Inc.
    Inventors: Masanobu Nakamura, Toshiro Kogawara, Hideki Gambayashi, Norio Aoki, Yoshinori Shimane, Ryozo Sugawara, Kinji Shinzo