Patents by Inventor Hiroshi Mizuhata

Hiroshi Mizuhata 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: 10662342
    Abstract: The present invention provides a water-based ink that is excellent in adhesion to a resin printing medium formed of a resin such as polyethylene terephthalate, polyvinyl chloride, polyethylene, polypropylene, nylon, etc., gloss and anti-blocking properties upon storage of the printing medium after printing. The present invention relates to [1] a water-based ink including a colorant, polyester resin particles and modified polyolefin resin particles, in which the polyester resin particles are constituted of a resin containing an amorphous polyester having a glass transition temperature of not lower than 40° C. and not higher than 100° C.
    Type: Grant
    Filed: March 31, 2016
    Date of Patent: May 26, 2020
    Assignee: KAO CORPORATION
    Inventors: Hiroto Soma, Hiroshi Mizuhata
  • Patent number: 10031432
    Abstract: According to the present invention, there are provided a process for producing a toner for development of electrostatic images which is capable of suppressing desorption and exposure of a releasing agent therein, and excellent in fusing property, suppression of toner cloud and durability; a process for producing a dispersion, and a kit for producing the dispersion.
    Type: Grant
    Filed: June 13, 2014
    Date of Patent: July 24, 2018
    Assignee: KAO CORPORATION
    Inventors: Hiroshi Mizuhata, Koji Shimokusa
  • Publication number: 20180134906
    Abstract: The present invention provides a water-based ink that is excellent in adhesion to a resin printing medium formed of a resin such as polyethylene terephthalate, polyvinyl chloride, polyethylene, polypropylene, nylon, etc., gloss and anti-blocking properties upon storage of the printing medium after printing. The present invention relates to [1] a water-based ink including a colorant, polyester resin particles and modified polyolefin resin particles, in which the polyester resin particles are constituted of a resin containing an amorphous polyester having a glass transition temperature of not lower than 40° C. and not higher than 100° C.
    Type: Application
    Filed: March 31, 2016
    Publication date: May 17, 2018
    Applicant: Kao Corporation
    Inventors: Hiroto SOMA, Hiroshi MIZUHATA
  • Patent number: 9529290
    Abstract: The present invention relates to a process for producing a toner for electrophotography which is capable of suppressing liberation of a wax from a resin binder and exposure of the wax to a surface of respective toner particles in the step of obtaining fused particles upon production of the toner, and reducing a content of fine powders in the toner, and which is characterized by an excellent low-temperature fusing property and an excellent anti-high-temperature offset property.
    Type: Grant
    Filed: October 4, 2013
    Date of Patent: December 27, 2016
    Assignee: KAO CORPORATION
    Inventors: Yasuhiro Shidahara, Manato Ikeda, Hiroshi Mizuhata, Koji Shimokusa
  • Publication number: 20160179021
    Abstract: According to the present invention, there are provided a process for producing a toner for development of electrostatic images which is capable of suppressing desorption and exposure of a releasing agent therein, and excellent in fusing property, suppression of toner cloud and durability; a process for producing a dispersion, and a kit for producing the dispersion.
    Type: Application
    Filed: June 13, 2014
    Publication date: June 23, 2016
    Applicant: KAO CORPORATION
    Inventors: Hiroshi MIZUHATA, Koji SHIMOKUSA
  • Publication number: 20150277250
    Abstract: The present invention relates to a process for producing a toner for electrophotography which is capable of suppressing liberation of a wax from a resin binder and exposure of the wax to a surface of respective toner particles in the step of obtaining fused particles upon production of the toner, and reducing a content of fine powders in the toner, and which is characterized by an excellent low-temperature fusing property and an excellent anti-high-temperature offset property.
    Type: Application
    Filed: October 4, 2013
    Publication date: October 1, 2015
    Applicant: KAO CORPORATION
    Inventors: Yasuhiro Shidahara, Manato Ikeda, Hiroshi Mizuhata, Koji Shimokusa
  • Patent number: 9005868
    Abstract: The present invention relates to a process for producing a toner for electrophotography which includes the step of fusing aggregated particles containing resin particles (A) and releasing agent particles in an aqueous mixed solution containing the aggregated particles and an anionic surfactant having a polyalkylene glycol moiety with an average molar number of addition of an alkylene oxide having 2 to 3 carbon atoms of from 5 to 100 after and/or while adjusting a pH value of the aqueous mixed solution to 2.0 to 6.0 as measured at 25° C., and a toner for electrophotography obtained by the process.
    Type: Grant
    Filed: December 9, 2011
    Date of Patent: April 14, 2015
    Assignee: Kao Corporation
    Inventors: Shoichi Murata, Takayuki Ikenaga, Takashi Okuno, Hiroshi Mizuhata, Keishi Yokota, Koji Shimokusa, Koji Kameyama
  • Patent number: 8980522
    Abstract: The present invention relates to a process for producing a toner for development of electrostatic latent images which includes a step (1) of mixing and aggregating resin particles (A), releasing agent particles and an aggregating agent formed of a divalent to pentavalent amine salt in an aqueous medium to obtain aggregated particles, and a toner for development of electrostatic latent images obtained by the process.
    Type: Grant
    Filed: December 21, 2011
    Date of Patent: March 17, 2015
    Assignee: Kao Corporation
    Inventor: Hiroshi Mizuhata
  • Patent number: 8956798
    Abstract: The present invention relates to a process for producing a toner for electrophotography which is excellent in dispersibility of a colorant in the toner and capable of considerably improving an image density, as well as a toner for electrophotography which is produced by the process. There is provided a process for producing a toner for electrophotography which includes the step of mixing a dispersion of colorant-containing polymer particles with a dispersion of resin particles containing substantially no colorant to aggregate the colorant-containing polymer particles and the resin particles, wherein the polymer contains a constitutional unit derived from a salt-forming group-containing monomer (a) and a constitutional unit derived from an aromatic ring-containing monomer (b).
    Type: Grant
    Filed: July 15, 2009
    Date of Patent: February 17, 2015
    Assignee: Kao Corporation
    Inventors: Shinichi Sata, Takehiro Tsutsumi, Hiroshi Mizuhata
  • Patent number: 8940468
    Abstract: Disclosed is a process for production of a decolorable toner, including: aggregating dispersed fine particles of a color material comprising at least a color-forming compound, a color-developing agent and a decoloring agent with dispersed fine particles comprising at least a binder resin comprising a polyester resin to form aggregates in an aqueous medium, adding a reactive polymer having an oxazoline group in to the aqueous medium, and fusing the aggregates in the aqueous medium. As a result, it becomes possible to produce a decolorable toner which suppresses the generation of fine powder due to the release of fine particles of an erasable color material from the toner.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: January 27, 2015
    Assignee: Toshiba Tec Kabushiki Kaisha
    Inventors: Takayasu Aoki, Takafumi Hara, Tsuyoshi Itou, Masahiro Ikuta, Motonari Udo, Koji Shimokusa, Hiroshi Mizuhata
  • Patent number: 8652746
    Abstract: The present invention relates to a process for producing a dispersion of polyester particles which includes the step of emulsifying mixed polyester containing (1) an amorphous polyester containing a constitutional unit derived from a trivalent or higher-valent carboxylic acid in an amount of from 2.0 to 12.0 mol % on the basis of whole constitutional units of the whole amorphous polyester and (2) a crystalline polyester, in an aqueous medium in a single vessel, or the step of mixing the mixed polyester with an organic solvent and then adding the aqueous medium to the resulting mixture to emulsify the mixed polyester in a single vessel.
    Type: Grant
    Filed: September 7, 2009
    Date of Patent: February 18, 2014
    Assignee: Kao Corporation
    Inventors: Shoichi Murata, Hiroshi Mizuhata, Nobumichi Kamiyoshi, Eiji Shirai
  • Patent number: 8652748
    Abstract: The invention provides a process for producing a toner for electrophotography including the following (1) to (4): (1): adding an aggregating agent to a resin particle dispersion (a) so as to attain an aggregating agent concentration Ea (wt %), to thereby produce an aggregated particle dispersion (A); (2): adding a resin microparticle dispersion (b) to the dispersion (A), to thereby produce a dispersion (B) having an aggregating agent concentration Eb (wt %) satisfying 0.60?Eb/Ea<1; (3): modifying the aggregating agent concentration of the dispersion (B), to thereby produce a dispersion (C) of resin microparticle-deposited aggregated particles, having an aggregating agent concentration Ec (wt %) satisfying 0<Ec/Ea?0.30; and (4): heating the resin microparticle-deposited aggregated particles in the dispersion (C) at a temperature falling within a range between Tg and Tg+20 (0 C) of the resin microparticles in the resin microparticle dispersion (b), to thereby coalesce the aggregated particles.
    Type: Grant
    Filed: December 22, 2010
    Date of Patent: February 18, 2014
    Assignee: Kao Corporation
    Inventors: Manabu Suzuki, Hiroshi Mizuhata
  • Patent number: 8632936
    Abstract: A method for producing an electrophotographic toner, including steps of: (1) preparing a thermally treated resin particle dispersion by retaining, for one hour or longer at a temperature satisfying the formula: (melting point of the crystalline polyester (a1)?35) (° C.)<T<melting point of the crystalline polyester (a1) (° C.), a dispersion of resin particles (A) having a volume median particle size of 0.
    Type: Grant
    Filed: December 17, 2010
    Date of Patent: January 21, 2014
    Assignee: KAO Corporation
    Inventors: Shoichi Murata, Eiji Shirai, Hiroshi Mizuhata, Manabu Suzuki
  • Publication number: 20130316284
    Abstract: The present invention relates to a process for producing a toner for development of electrostatic latent images which includes a step (1) of mixing and aggregating resin particles (A), releasing agent particles and an aggregating agent formed of a divalent to pentavalent amine salt in an aqueous medium to obtain aggregated particles, and a toner for development of electrostatic latent images obtained by the process.
    Type: Application
    Filed: December 21, 2011
    Publication date: November 28, 2013
    Applicant: KAO CORPORATION
    Inventor: Hiroshi Mizuhata
  • Publication number: 20130295499
    Abstract: The present invention relates to a process for producing a toner for electrophotography which includes the step of fusing aggregated particles containing resin particles (A) and releasing agent particles in an aqueous mixed solution containing the aggregated particles and an anionic surfactant having a polyalkylene glycol moiety with an average molar number of addition of an alkylene oxide having 2 to 3 carbon atoms of from 5 to 100 after and/or while adjusting a pH value of the aqueous mixed solution to 2.0 to 6.0 as measured at 25° C., and a toner for electrophotography obtained by the process.
    Type: Application
    Filed: December 9, 2011
    Publication date: November 7, 2013
    Applicant: KAO CORPORATION
    Inventors: Shoichi Murata, Takayuki Ikenaga, Takashi Okuno, Hiroshi Mizuhata, Keishi Yokota, Koji Shimokusa, Koji Kameyama
  • Patent number: 8574808
    Abstract: The present invention relates to a resin emulsion being produced by neutralizing a resin binder containing acid group with a basic compound in an aqueous medium wherein the resin binder containing acid group contains a polyester produced from a raw monomer composition containing a trivalent or higher-valent polyhydric alcohol in an amount of 1 to 15 mol %; a process for producing the resin emulsion; and a toner for electrophotography using the resin emulsion. In the resin emulsion of the present invention, a resin is readily emulsified therein even when using a crosslinked polyester as the resin, and the resin emulsion is substantially free from hydrolysis of the resin and can produce a toner having an excellent heat-resistant storage property.
    Type: Grant
    Filed: July 6, 2007
    Date of Patent: November 5, 2013
    Assignee: KAO Corporation
    Inventors: Hiroshi Mizuhata, Takashi Kubo, Takashi Mukai
  • Patent number: 8460847
    Abstract: The present invention relates to a toner for electrophotography including a polyester obtained by subjecting a crystalline polyester-containing aqueous dispersion and a non-crystalline polyester-containing aqueous dispersion to aggregation and coalescence, as a resin binder, wherein the crystalline polyester is produced by polycondensing an alcohol component containing 70 mol % or more of an aliphatic diol having 2 to 8 carbon atoms with a carboxylic acid component containing 50 mol % or more of terephthalic acid. The toner is excellent in low-temperature fusing ability and pressure storage stability.
    Type: Grant
    Filed: August 14, 2009
    Date of Patent: June 11, 2013
    Assignee: Kao Corporation
    Inventors: Eiji Shirai, Takashi Kubo, Hiroshi Mizuhata, Shoichi Murata
  • Publication number: 20130011777
    Abstract: Disclosed is a process for production of a decolorable toner, including: aggregating dispersed fine particles of a color material comprising at least a color-forming compound, a color-developing agent and a decoloring agent with dispersed fine particles comprising at least a binder resin comprising a polyester resin to form aggregates in an aqueous medium, adding a reactive polymer having an oxazoline group in to the aqueous medium, and fusing the aggregates in the aqueous medium. As a result, it becomes possible to produce a decolorable toner which suppresses the generation of fine powder due to the release of fine particles of an erasable color material from the toner.
    Type: Application
    Filed: June 29, 2012
    Publication date: January 10, 2013
    Applicant: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Takayasu Aoki, Takafumi Hara, Tsuyoshi Itou, Masahiro Ikuta, Motonari Udo, Koji Shimokusa, Hiroshi Mizuhata
  • Patent number: 8288070
    Abstract: The present invention relates to a toner for electrophotography which exhibits an excellent heat-resistant storage property and a wide fusing temperature range, and a process for producing the toner for electrophotography.
    Type: Grant
    Filed: August 6, 2008
    Date of Patent: October 16, 2012
    Assignee: Kao Corporation
    Inventors: Hiroshi Mizuhata, Yutaka Murai, Manabu Suzuki, Hiromi Nambu
  • Publication number: 20120258392
    Abstract: A method for producing an electrophotographic toner, including (1) a step of preparing a thermally treated resin particle dispersion by retaining, for one hour or longer at a temperature satisfying a specific formula, a dispersion of resin particles (A) having a volume median particle size of 0.02 ?m to 2 ?m and containing a resin containing a crystalline polyester (a1) in an amount of 1 to 50 wt % and an amorphous polyester (b1); (2) a step of preparing an aggregated particle dispersion by aggregating thermally treated resin particles contained in the thermally treated resin particle dispersion prepared through step 1; (2a) a step of preparing resin-fine-particle-attached aggregated particles by adding, to the aggregated particle dispersion prepared through step 2, a dispersion of resin fine particles (B) containing an amorphous polyester (b2) in an amount of 70 wt % or more; and (3) a step of unifying the resin-fine-particle-attached aggregated particles prepared through step 2a.
    Type: Application
    Filed: December 17, 2010
    Publication date: October 11, 2012
    Inventors: Shoichi Murata, Eiji Shirai, Hiroshi Mizuhata, Manabu Suzuki