Patents by Inventor Akihiro Eida

Akihiro Eida 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
  • Patent number: 8993207
    Abstract: A method for forming fixed images including the step of applying a toner for electrostatic image development containing at least a resin binder, a colorant, and a releasing agent to an apparatus for forming fixed images without a filter in a gas discharge part, wherein the resin binder contains a polyester, and wherein the releasing agent is a hydrocarbon-based wax, wherein the hydrocarbon-based wax has a melting point as determined by a differential scanning calorimeter of from 70° to 85° C., and contains components melting at a temperature equal to or lower than 65° C. having an amount of heat absorption as determined by a differential scanning calorimeter of less than 7.5 J/g, and a toner for electrostatic image development used in a method for forming fixed images. The method for forming fixed images of the present invention is suitably used in the development of a latent image formed in, for example, electrophotography, electrostatic recording method, electrostatic printing method or the like.
    Type: Grant
    Filed: November 16, 2011
    Date of Patent: March 31, 2015
    Assignee: Kao Corporation
    Inventors: Akihiro Eida, Yasuhiro Hidaka
  • Patent number: 8609313
    Abstract: A toner containing a resin binder and a colorant, wherein the resin binder contains a crystalline resin and an amorphous resin, the crystalline resin containing a composite resin containing: a polycondensation resin component obtained by polycondensing an alcohol component containing an aliphatic diol having 2 to 10 carbon atoms, and a carboxylic acid component containing an aromatic dicarboxylic acid compound, and a styrenic resin component, and the amorphous resin containing a polyester obtained from an alcohol component containing an aliphatic diol in an amount of 60% by mol or more, and a carboxylic acid component. The toner of the present invention is suitably 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: May 13, 2011
    Date of Patent: December 17, 2013
    Assignee: Kao Corporation
    Inventors: Akihiro Eida, Shogo Watanabe, Takashi Kubo
  • Patent number: 8592127
    Abstract: A method for producing a toner, comprising the step of feeding raw materials containing a resin binder and a colorant to an open-roller type kneader, and melt-kneading the raw materials, wherein the resin binder contains a crystalline polyester and an amorphous polyester, and wherein the crystalline polyester and the amorphous polyester fed to the open-roller type kneader are in a weight ratio, i.e. crystalline polyester/amorphous polyester, of from 5/95 to 30/70, and have a ratio of average particle sizes of crystalline polyester/amorphous polyester of from 1.5 to 4.0. The toner obtained according to the present invention 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 28, 2009
    Date of Patent: November 26, 2013
    Assignee: Kao Corporation
    Inventor: Akihiro Eida
  • Publication number: 20130183617
    Abstract: A method for forming fixed images including the step of applying a toner for electrostatic image development containing at least a resin binder, a colorant, and a releasing agent to an apparatus for forming fixed images without a filter in a gas discharge part, wherein the resin binder contains a polyester, and wherein the releasing agent is a hydrocarbon-based wax, wherein the hydrocarbon-based wax has a melting point as determined by a differential scanning calorimeter of from 70° to 85° C., and contains components melting at a temperature equal to or lower than 65° C. having an amount of heat absorption as determined by a differential scanning calorimeter of less than 7.5 J/g, and a toner for electrostatic image development used in a method for forming fixed images. The method for forming fixed images of the present invention is suitably used in the development of a latent image formed in, for example, electrophotography, electrostatic recording method, electrostatic printing method or the like.
    Type: Application
    Filed: November 16, 2011
    Publication date: July 18, 2013
    Applicant: Kao Corporation
    Inventors: Akihiro Eida, Yasuhiro Hidaka
  • 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
  • Publication number: 20110294062
    Abstract: A toner containing a resin binder and a colorant, wherein the resin binder contains a crystalline resin and an amorphous resin, the crystalline resin containing a composite resin containing: a polycondensation resin component obtained by polycondensing an alcohol component containing an aliphatic diol having 2 to 10 carbon atoms, and a carboxylic acid component containing an aromatic dicarboxylic acid compound, and a styrenic resin component, and the amorphous resin containing a polyester obtained from an alcohol component containing an aliphatic diol in an amount of 60% by mol or more, and a carboxylic acid component. The toner of the present invention is suitably 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: May 13, 2011
    Publication date: December 1, 2011
    Inventors: Akihiro EIDA, Shogo WATANABE, Takashi KUBO
  • Patent number: 8039191
    Abstract: A toner having a BET specific surface area of from 1.5 to 3.5 m2/g, obtainable by a process including the steps of; step (1): pulverizing a toner composition containing at least a resin binder and a colorant in the presence of fine inorganic particles having an average primary particle size of from 6 to 20 nm to obtain mother toner particles having a volume-median particle size of from 3 to 8 ?m; and step (2): externally adding silica having an average primary particle size of from 25 to 60 nm to the mother toner particles obtained in the above step (1). The toner 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: June 6, 2007
    Date of Patent: October 18, 2011
    Assignee: Kao Corporation
    Inventor: Akihiro Eida
  • 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: 7820353
    Abstract: A method for producing a toner, including at least the following steps: step (A): pulverizing a negatively chargeable charge control resin that does not soften at a temperature of 180° C. or lower to an average particle size of from 0.05 to 2 ?m; step (B): melt-kneading at least a pulverized product of the negatively chargeable charge control resin obtained in the step (A), a resin binder, and a colorant; and step (C): pulverizing a melt-kneaded product obtained in the step (B) and classifying the pulverized product. The toner obtained according to the present invention is suitably 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: November 18, 2008
    Date of Patent: October 26, 2010
    Assignee: Kao Corporation
    Inventors: Akihiro Eida, Takeshi Ashizawa
  • Publication number: 20100266822
    Abstract: A process for preparing a black toner for electrophotography, including the steps of (I) melt-kneading a raw material mixture containing a resin binder and a black colorant with an open-roller type kneader; (II) cooling the melt-kneaded mixture obtained in the step (I) and pulverizing the cooled mixture; and (III) classifying the pulverized product obtained in the step (II), wherein the resulting toner has a volume-median particle size (D50v) of from 3 to 6.5 ?m, contains 5.0% by volume or less of particles having particle sizes of (1.4×D50v) ?m or more, and contains 5.0% by number or less of particles having particle sizes of (0.6×number-median particle size (D50p)) ?m or less; and a black toner for electrophotography obtained by the process as defined above, wherein the toner is a toner for nonmagnetic monocomponent development. The black toner is used for development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method, or the like.
    Type: Application
    Filed: June 30, 2010
    Publication date: October 21, 2010
    Applicant: KAO CORPORATION
    Inventors: Akihiro Eida, Takashi Okuno
  • Publication number: 20100136469
    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: Application
    Filed: November 16, 2009
    Publication date: June 3, 2010
    Applicant: KAO CORPORATION
    Inventors: Hisakazu TAJIMA, Kohei Katayama, Eiji Shirai, Akihiro Eida
  • Publication number: 20100035175
    Abstract: A method for producing a toner, comprising the step of feeding raw materials containing a resin binder and a colorant to an open-roller type kneader, and melt-kneading the raw materials, wherein the resin binder contains a crystalline polyester and an amorphous polyester, and wherein the crystalline polyester and the amorphous polyester fed to the open-roller type kneader are in a weight ratio, i.e. crystalline polyester/amorphous polyester, of from 5/95 to 30/70, and have a ratio of average particle sizes of crystalline polyester/amorphous polyester of from 1.5 to 4.0. The toner obtained according to the present invention 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 28, 2009
    Publication date: February 11, 2010
    Applicant: KAO CORPORATION
    Inventor: Akihiro EIDA
  • Patent number: 7566518
    Abstract: The present invention relates to a toner for electrostatic image development, obtainable by a process including the steps of: (I) melt-kneading a raw material mixture containing a resin binder, a releasing agent, and a colorant, cooling the melt-kneaded mixture, and pulverizing the cooled mixture; and (II) further pulverizing a pulverized product obtained in the step (I) in the presence of an external additive containing a negatively chargeable inorganic oxide subjected to hydrophobic treatment and a positively chargeable inorganic oxide subjected to hydrophobic treatment, and classifying the pulverized product; and a process for preparing the toner.
    Type: Grant
    Filed: April 11, 2005
    Date of Patent: July 28, 2009
    Assignee: Kao Corporation
    Inventors: Akihiro Eida, Jun Shimizu
  • Publication number: 20090136865
    Abstract: A method for producing a toner, including at least the following steps: step (A): pulverizing a negatively chargeable charge control resin that does not soften at a temperature of 180° C. or lower to an average particle size of from 0.05 to 2 ?m; step (B): melt-kneading at least a pulverized product of the negatively chargeable charge control resin obtained in the step (A), a resin binder, and a colorant; and step (C): pulverizing a melt-kneaded product obtained in the step (B) and classifying the pulverized product. The toner obtained according to the present invention is suitably 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: November 18, 2008
    Publication date: May 28, 2009
    Applicant: KAO CORPORATION
    Inventors: Akihiro Eida, Takeshi Ashizawa
  • Publication number: 20090123863
    Abstract: A method for producing a toner for electrostatic image development, including the steps of melt-kneading a resin binder containing a crystalline polyester and an amorphous resin as main components, and heat-treating the melt-kneaded product obtained in the step of melt-kneading at a temperature of from 50° to 80° C., wherein the crystalline polyester is obtained by a polycondensation reaction of an ?,?-linear alkanediol and an aliphatic dicarboxylic acid compound, has the specified values of properties, and further is contained in an amount of from 1 to 35% by weight of the resin binder. The toner for electrostatic image development obtained by 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: Application
    Filed: November 4, 2008
    Publication date: May 14, 2009
    Applicant: KAO CORPORATION
    Inventors: Takeshi ASHIZAWA, Akihiro Eida
  • Patent number: 7449275
    Abstract: A process for preparing a toner including the steps of (I) melt-kneading a raw material mixture containing a resin binder and a colorant; (II) cooling the melt-kneaded mixture obtained in the step (I) and pulverizing the cooled mixture to give a pulverized product having a volume-median particle size (D50v) of from 10 to 1000 ?m; (III) pulverizing the pulverized product obtained in the step (II) in the presence of an external additive having an average particle size of from 8 to 50 nm; and (IV) classifying the pulverized product obtained in the step (III), wherein the resulting toner has a volume-median particle size (D50v) of from 3.5 to 8 ?m, and the total amount of m kind(s) of external additive(s) in the step (III) satisfies a specified formula. The toner can be used, for instance, for the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.
    Type: Grant
    Filed: September 19, 2005
    Date of Patent: November 11, 2008
    Assignee: Kao Corporation
    Inventor: Akihiro Eida
  • Patent number: 7442482
    Abstract: A process for preparing a toner including the steps of (I) melt-kneading a raw material mixture containing a resin binder, a wax, and a colorant with an open-roller type kneader; (II) cooling the melt-kneaded mixture obtained in the step (I) and pulverizing the cooled mixture; and (III) classifying the pulverized product obtained in the step (II) to give a toner, wherein the wax is contained in the toner in an amount of from 2 to 15% by weight, and has a number-average particle size in the toner of 1 ?m or less, wherein the toner has a volume-median particle size (D50) of from 3.5 to 7 ?m, and a standard deviation in volume base particle size distribution of ¼ of D50 or less, and contains 5% by volume or less of particles having particle sizes of (1.4×D50) ?m or more, and 5% by number or less of particles having particle sizes of 3 ?m or less.
    Type: Grant
    Filed: September 16, 2005
    Date of Patent: October 28, 2008
    Assignee: Kao Corporation
    Inventor: Akihiro Eida
  • Patent number: 7384721
    Abstract: The present invention relates to a toner for electrostatic image development, obtainable by a process including the steps of (I) melt-kneading a raw material mixture comprising a resin binder, a releasing agent, and a colorant; cooling the melt-kneaded mixture; and pulverizing the cooled mixture; and (II) further pulverizing a pulverized product obtained in the step (I) in the presence of an external additive; and classifying the pulverized product, wherein the releasing agent in the step (I) contains a wax having a melting point of from 65° to 100° C., and wherein the external additive in the step (II) contains specified inorganic oxides. The toner of the present invention can be suitably used, for instance, for the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.
    Type: Grant
    Filed: April 11, 2005
    Date of Patent: June 10, 2008
    Assignee: Kao Corporation
    Inventors: Akihiro Eida, Jun Shimizu
  • Patent number: 7348120
    Abstract: The present invention relates to a toner for electrostatic image development, obtainable by a process including the steps of (I) melt-kneading a raw material mixture containing a resin binder, a releasing agent, and a colorant; cooling the melt-kneaded mixture; and pulverizing the cooled mixture; and (II) further pulverizing a pulverized product obtained in the step (I) in the presence of an external additive containing at least two kinds of inorganic oxides subjected to hydrophobic treatment, having different average particle sizes from each other; and classifying the pulverized product, wherein the inorganic oxides subjected to hydrophobic treatment in the step (II) have an average particle size of 20 nm or less, and a difference in average particle size of 3 to 10 nm; and a process for preparing the toner.
    Type: Grant
    Filed: April 11, 2005
    Date of Patent: March 25, 2008
    Assignee: Kao Corporation
    Inventors: Akihiro Eida, Jun Shimizu