Patents by Inventor Eiji Shirai

Eiji Shirai 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: 9017912
    Abstract: A method for producing a toner including the steps of melt-kneading at least a resin binder and a colorant to give a kneaded product (step 1); and heat-treating the kneaded product obtained in the step 1 (step 2), wherein the resin binder contains a crystalline resin and an amorphous resin, wherein the crystalline resin contains a specified composite resin containing (a) a specified polycondensation resin component and (b) a styrenic resin component, in a specified weight ratio, wherein the composite resin is contained in the resin binder in a specified amount. The toner obtained by the above method is used in, for example, the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.
    Type: Grant
    Filed: July 13, 2010
    Date of Patent: April 28, 2015
    Assignee: Kao Corporation
    Inventors: Akihiro Eida, Koji Kameyama, Eiji Shirai
  • Publication number: 20140363765
    Abstract: A method for producing a toner for electrostatic image development, including the steps of (1) polycondensing an alcohol component, a carboxylic acid component, and polyethylene terephthalate to provide an amorphous polyester; and (2) subjecting the amorphous polyester obtained in the step (1) and components containing a crystalline polyester in an amount of from 0.3 to 2.5 times the mass of the components derived from the polyethylene terephthalate in the amorphous polyester to a process for producing a toner. The toner for electrostatic image development obtained by the method of the present invention is suitably used in development or the like of latent images formed in, for example, an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or the like.
    Type: Application
    Filed: April 30, 2014
    Publication date: December 11, 2014
    Applicant: Kao Corporation
    Inventors: Norihiro FUKURI, Eiji SHIRAI
  • Patent number: 8802342
    Abstract: The present invention relates to a crystalline resin for toners which includes a composite resin including a polycondensation-based resin component obtained by polycondensing an alcohol component containing an aliphatic diol having 2 to 10 carbon atoms with a carboxylic acid component containing an aromatic dicarboxylic acid, and a styrene-based resin component; a resin binder containing the crystalline resin and a non-crystalline resin; and a toner for electrophotography which contains the resin binder. According to the present invention, there are provided a crystalline resin for toners which is capable of producing a toner that is excellent in not only low-temperature fixing ability but also gloss of images and anti-filming property, a resin binder, and a toner for electrophotography.
    Type: Grant
    Filed: December 9, 2009
    Date of Patent: August 12, 2014
    Assignee: Kao Corporation
    Inventors: Eiji Shirai, Tetsuya Ueno
  • Patent number: 8722297
    Abstract: The present invention relates to a resin binder for toners which contains a crystalline polyester which is produced by polycondensing at least an alcohol component containing an aliphatic diol having 2 to 12 carbon atoms and a carboxylic acid component containing an aliphatic dicarboxylic acid compound having 8 to 12 carbon atoms in an amount of from 70 to 100 mol %, wherein a content of a methyl ethyl ketone soluble component (at 20° C.) in the crystalline polyester is from 0.5 to 7% by weight on the basis of a weight of the crystalline polyester, and a difference between a melting point of the crystalline polyester and a peak top temperature observed in DSC measurement of the methyl ethyl ketone soluble component (“melting point of the crystalline polyester”?“peak top temperature observed in DSC measurement of the methyl ethyl ketone soluble component”) is within the range of from 1 to 15° C.
    Type: Grant
    Filed: March 8, 2011
    Date of Patent: May 13, 2014
    Assignee: Kao Corporation
    Inventors: Eiji Shirai, Hiroki Kakiuchi
  • 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: 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
  • 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
  • Patent number: 8389189
    Abstract: The present invention relates to a resin binder for toners which includes core/shell particles each including a core portion containing a crystalline polyester obtained by polycondensing an alcohol component containing an aliphatic diol having 2-12 carbon atoms and a carboxylic acid component containing an aliphatic dicarboxylic acid compound having 8-12 carbon atoms in an amount of 70-100 mol %, and a non-crystalline resin (A) obtained by polycondensing an alcohol component and a carboxylic acid component containing at least one succinic acid compound selected from the group consisting of an alkyl (C9-C18) succinic acid and an alkenyl (C9-C18) succinic acid in an amount of 3-60 mol %; and a shell portion containing a non-crystalline resin (B) obtained by polycondensing a carboxylic acid component and an alcohol component containing an aliphatic dialcohol having 2-5 carbon atoms in an amount of 80 mol % or more.
    Type: Grant
    Filed: March 2, 2011
    Date of Patent: March 5, 2013
    Assignee: Kao Corporation
    Inventors: Eiji Shirai, Shoichi Murata
  • Patent number: 8318634
    Abstract: The present invention relates to a resin for use in a thermal transfer image-receiving sheet which is excellent in dyeability with dyes and releasability of the sheet, a resin dispersion using the resin, and a thermal transfer image-receiving sheet. The resin for a thermal transfer image-receiving sheet is obtained by addition polymerizing and condensation polymerizing (a) raw monomers of a polyester, (b) a raw monomer of an addition polymer-based resin containing at least one compound selected from the group consisting of styrene and styrene derivatives and (c) at least one dually reactive monomer selected from the group consisting of acrylic acid, methacrylic acid and derivatives of these acids, wherein the raw monomers (a) of a polyester include an alcohol component containing 80 mol % or more of an alkyleneoxide adduct of 2,2-bis(4-hydroxyphenyl)propane.
    Type: Grant
    Filed: December 3, 2009
    Date of Patent: November 27, 2012
    Assignee: Kao Corporation
    Inventors: Yoshiaki Ban, Eiji Shirai, Nobumichi Kamiyoshi, Yuuta Matsumoto, Takashi Mukai
  • Patent number: 8288499
    Abstract: A polyester for a toner having a softening point of from 70° to 110° C. and a glass transition temperature of from 38° to 60° C., obtained by polycondensing an alcohol component containing a propylene oxide adduct of bisphenol A and an ethylene oxide adduct of bisphenol A in a total amount of 80% by mole or more, with a carboxylic acid component, wherein the propylene oxide adduct has an average number of moles of from 2.0 to 2.4, and the ethylene oxide adduct has an average number of moles of from 2.5 to 4.2. The polyester for a toner of the present invention is suitably used as a resin binder of a toner, or the like, used for, for example, developing a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method, or the like.
    Type: Grant
    Filed: December 31, 2007
    Date of Patent: October 16, 2012
    Assignee: Kao Corporation
    Inventors: Eiji Shirai, Yoshitomo Kimura, Yasunori Inagaki
  • 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
  • Patent number: 8221949
    Abstract: A toner containing a resin binder containing two kinds of polyesters having softening points that differ by 10° C. or more, a colorant and a charge control agent, wherein the two kinds of polyesters contain a polyester A having a softening point of from 105° to 140° C. and a glass transition temperature of from 30° to 55° C., and a polyester B having a softening point of from 140° to 170° C. and a glass transition temperature of exceeding 55° C. and 80° C. or lower. The toner of the present invention is usable in, for example, development of latent images formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.
    Type: Grant
    Filed: November 16, 2009
    Date of Patent: July 17, 2012
    Assignee: Kao Corporation
    Inventors: Hisakazu Tajima, Kohei Katayama, Eiji Shirai, Akihiro Eida
  • Patent number: 8071268
    Abstract: The present invention relates to a toner for electrophotography containing a resin binder, a colorant, and a clay-organic complex obtained by intercalating into a smectite clay a quaternary ammonium salt represented by the formula (A): [(R1)3(R2)N]+.X???(A) wherein R1 and R2 are not identical; R1 is an alkyl group, alkenyl group, or alkynyl group, each having 4 to 24 carbon atoms; R2 is an alkyl group, alkenyl group, or alkynyl group, each having 1 to 10 carbon atoms; and X? is an anion. The toner for electrophotography of the present invention is suitably used for, for example, developing a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method, or the like.
    Type: Grant
    Filed: August 3, 2006
    Date of Patent: December 6, 2011
    Assignee: Kao Corporation
    Inventors: Eiji Shirai, Satoshi Kunii
  • Publication number: 20110294061
    Abstract: The present invention relates to a crystalline resin for toners which includes a composite resin including a polycondensation-based resin component obtained by polycondensing an alcohol component containing an aliphatic diol having 2 to 10 carbon atoms with a carboxylic acid component containing an aromatic dicarboxylic acid, and a styrene-based resin component; a resin binder containing the crystalline resin and a non-crystalline resin; and a toner for electrophotography which contains the resin binder. According to the present invention, there are provided a crystalline resin for toners which is capable of producing a toner that is excellent in not only low-temperature fixing ability but also gloss of images and anti-filming property, a resin binder, and a toner for electrophotography.
    Type: Application
    Filed: December 9, 2009
    Publication date: December 1, 2011
    Applicant: Kao Corporation
    Inventors: Eiji Shirai, Tetsuya Ueno
  • Publication number: 20110229816
    Abstract: The present invention relates to a resin binder for toners which includes core/shell particles each including a core portion containing a crystalline polyester obtained by polycondensing an alcohol component containing an aliphatic dial having 2-12 carbon atoms and a carboxylic acid component containing an aliphatic dicarboxylic acid compound having 8-12 carbon atoms in an amount of 70-100 mol %, and a non-crystalline resin (A) obtained by polycondensing an alcohol component and a carboxylic acid component containing at least one succinic acid compound selected from the group consisting of an alkyl (C9-C18) succinic acid and an alkenyl (C9-C18) succinic acid in an amount of 3-60 mol %; and a shell portion containing a non-crystalline resin (B) obtained by polycondensing a carboxylic acid component and an alcohol component containing an aliphatic dialcohol having 2-5 carbon atoms in an amount of 80 mol % or more.
    Type: Application
    Filed: March 2, 2011
    Publication date: September 22, 2011
    Applicant: KAO CORPORATION
    Inventors: Eiji SHIRAI, Shoichi MURATA
  • Publication number: 20110217646
    Abstract: The present invention relates to a resin binder for toners which contains a crystalline polyester which is produced by polycondensing at least an alcohol component containing an aliphatic diol having 2 to 12 carbon atoms and a carboxylic acid component containing an aliphatic dicarboxylic acid compound having 8 to 12 carbon atoms in an amount of from 70 to 100 mol %, wherein a content of a methyl ethyl ketone soluble component (at 20° C.) in the crystalline polyester is from 0.5 to 7% by weight on the basis of a weight of the crystalline polyester, and a difference between a melting point of the crystalline polyester and a peak top temperature observed in DSC measurement of the methyl ethyl ketone soluble component (“melting point of the crystalline polyester”?“peak top temperature observed in DSC measurement of the methyl ethyl ketone soluble component”) is within the range of from 1 to 15° C.
    Type: Application
    Filed: March 8, 2011
    Publication date: September 8, 2011
    Applicant: KAO CORPORATION
    Inventors: Eiji SHIRAI, Hiroki KAKIUCHI
  • Publication number: 20110177445
    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: Application
    Filed: September 7, 2009
    Publication date: July 21, 2011
    Applicant: KAO CORPORATION
    Inventors: Shoichi Murata, Hiroshi Mizuhata, Nobumichi Kamiyoshi, Eiji Shirai
  • Publication number: 20110045402
    Abstract: A method for producing a toner including the steps of melt-kneading at least a resin binder and a colorant to give a kneaded product (step 1); and heat-treating the kneaded product obtained in the step 1 (step 2), wherein the resin binder contains a crystalline resin and an amorphous resin, wherein the crystalline resin contains a specified composite resin containing (a) a specified polycondensation resin component and (b) a styrenic resin component, in a specified weight ratio, wherein the composite resin is contained in the resin binder in a specified amount. The toner obtained by the above method is used in, for example, the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.
    Type: Application
    Filed: July 13, 2010
    Publication date: February 24, 2011
    Applicant: KAO CORPORATION
    Inventors: Akihiro Eida, Koji Kameyama, Eiji Shirai
  • Patent number: 7842448
    Abstract: A method of forming fixed images, including the step of applying a two-component developer containing a carrier and a toner containing a wax and a resin binder containing a crystalline polyester to a two-component development device with a linear speed of from 500 to 5,000 mm/sec, to develop the toner, wherein the crystalline polyester is contained in an amount of from 3 to 40% by weight and the wax in an amount of from 2.5 to 10% by weight, of the toner, and wherein the two-component development device comprises at least three magnet rollers which are arranged closely to each other along the perimeter of a photoconductor, wherein one magnet roller arranged on the uppermost side in the rotational direction of the photoconductor rotates in a direction opposite to the rotational direction of the photoconductor at the point therebetween, and the other magnet rollers rotate in the same direction as the photoconductor at the point therebetween.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: November 30, 2010
    Assignee: Kao Corporation
    Inventors: Shinji Moriyama, Yoshihiro Fukushima, Takashi Kubo, Yutaka Kanamaru, Eiji Shirai
  • Patent number: 7820354
    Abstract: The present invention relates to a process for producing a toner including the steps of melt-kneading raw materials containing two or more kinds of polyesters, heat-treating a melt-kneaded product, pulverizing a heat-treated product, and classifying a pulverized product, wherein the two or more kinds of polyesters contain at least one kind of an amorphous polyester, and the heat-treating step is carried out at a temperature t (° C.) and time h (hour) satisfying the following formulas (a) and (b), Tg1?t?Tm?10??(a) h?100/(t?30), with proviso that t>30??(b) wherein Tg1 is a glass transition temperature (° C.) of the melt-kneaded product before the heat-treating step; and Tm is the lowest softening point (° C.) of softening points of the two or more kinds of polyesters, and the toner produced by the process.
    Type: Grant
    Filed: April 20, 2005
    Date of Patent: October 26, 2010
    Assignee: Kao Corporation
    Inventor: Eiji Shirai