Patents by Inventor Masateru Kawamura

Masateru Kawamura 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: 9557681
    Abstract: A developing device includes a casing configured to accommodate developer, a developing roller, a seal member, at least portion of which is disposed between the developing roller and the casing, and which includes a fabric member including a plurality of first fibers extending in a first direction, and a heat radiation member configured to contact end surfaces of the first fibers of the seal member and radiate heat of the seal member.
    Type: Grant
    Filed: December 24, 2013
    Date of Patent: January 31, 2017
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Kenjiro Nishiwaki, Takanori Uno, Takuya Amaike, Masateru Kawamura, Kazuna Taguchi, Motoaki Mushika, Yasuo Fukamachi, Shunji Yoshimoto, Masahiro Ishii
  • Publication number: 20140178093
    Abstract: A developing device includes a casing configured to accommodate developer, a developing roller, a seal member, at least portion of which is disposed between the developing roller and the casing, and which includes a fabric member including a plurality of first fibers extending in a first direction, and a heat radiation member configured to contact end surfaces of the first fibers of the seal member and radiate heat of the seal member.
    Type: Application
    Filed: December 24, 2013
    Publication date: June 26, 2014
    Applicant: BROTHER KOGYO KABUSHIKI KAISHA
    Inventors: Kenjiro Nishiwaki, Takanori Uno, Takuya Amaike, Masateru Kawamura, Kazuna Taguchi, Motoaki Mushika, Yasuo Fukamachi, Shunji Yoshimoto, Masahiro Ishii
  • Patent number: 8343704
    Abstract: Spherical-shaped liquid droplets are made by dispersing oil phase containing: a resin with an acid group, a first hydrophobic solvent effecting dissolution of the resin, a colorant, and a charge control agent which is positively charged in an aqueous dispersion medium in the presence of a base; and the liquid particles are solidified to be solid particles by removing the first solvent from the liquid droplets. The solid particles obtained in this manner are washed with a second solvent. As the second solvent, a solvent which dissolves the charge control agent and but does not dissolve the resin such as alcohol is selected. Accordingly, the charge control agent in the solid particles are made to elute to the outer surface layer of the solid particles, thereby improving the positive chargeability of the solid particles.
    Type: Grant
    Filed: June 16, 2006
    Date of Patent: January 1, 2013
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Jun Ikama, Masateru Kawamura
  • Patent number: 8263305
    Abstract: Provided is a method for producing a toner having excellent particle size distribution and storage stability. The method set forth in the present specification is a method for producing a toner by aggregating and fusing base microparticles whose main component is a binder resin including anionic groups, wherein an aggregate is produced by aggregating the base microparticles in a base microparticle suspension, in a presence of a non-ionic surfactant such that a surface tension of an aqueous solution thereof is not lower than 45 mN/m at any concentration at or above a critical micelle concentration, and the toner is produced through fusion of the aggregate. According to this method, drops in a glass transition temperature of the toner can be curbed, and the toner having excellent storage stability and good particle size distribution can be obtained.
    Type: Grant
    Filed: March 30, 2010
    Date of Patent: September 11, 2012
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Jun Ikami, Masateru Kawamura, Yasutomo Imai
  • Patent number: 8224216
    Abstract: A developing apparatus is described. The developing apparatus includes a transport member including a plurality of electrodes forming a traveling wave electric field by successively applied voltages and a casing storing a toner transported by the transport member, wherein the activity of the toner based on the following measuring method shown in (1) to (3) is not more than 2.
    Type: Grant
    Filed: April 30, 2008
    Date of Patent: July 17, 2012
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Jun Ikami, Masateru Kawamura
  • Patent number: 8119319
    Abstract: The present teaching provides a method for producing a positive charging toner that can exhibit stable charge characteristics. According to the present teaching, a positive charging toner is produced by preparing a base particle suspension having a conductivity not higher than 70 ?S/cm and comprising base particles that are obtained by mixing and emulsifying an aqueous medium and a resin solution containing the polyester resin; producing toner base particles by mixing the base particle suspension with a charge control resin microparticle suspension containing charge control resin microparticles; causing the charge control resin microparticles to adhere to the surfaces of the base particles; and washing the toner base particles.
    Type: Grant
    Filed: March 31, 2009
    Date of Patent: February 21, 2012
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Masateru Kawamura, Yasutomo Imai
  • Patent number: 8029967
    Abstract: Provided is a method for producing a toner including the steps of: preparing a resin liquid by mixing at least a binder resin made of polyester resin and a colorant with an ester organic solvent represented by the following general formula (1); dispersing the resin liquid in an aqueous medium to form an emulsion; and removing the ester organic solvent from the emulsion to produce a toner, in which the ester organic solvent before the preparation of the resin liquid contains water in an amount of not less than 1% by weight and up to the saturation solubility at 25° C. to the ester organic solvent: (in which R1 is a hydrogen atom or a methyl group, and R2 is an alkyl group having 1 to 4 carbon atoms).
    Type: Grant
    Filed: January 22, 2009
    Date of Patent: October 4, 2011
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Masateru Kawamura, Jun Ikami, Takanori Uno, Tomoaki Hattori
  • Patent number: 7960085
    Abstract: A method for producing a positively chargeable toner is described. The method for producing a positively chargeable toner may include the steps of: mixing and emulsifying a charge-controlling resin having a positive polar group, an organic solvent and an aqueous medium to form an emulsion, and then removing the organic solvent from the emulsion, to thereby form a suspension of the charge-controlling resin having a positive polar group in the range of 5.0×10?5 to 6.0×10?4 mol/g; mixing the suspension of the charge-controlling agent with a suspension of toner base particles containing a binder resin and a colorant, to thereby form a mixture; and heating the mixture containing the suspension of the toner base particles and the suspension of the charge-controlling resin, to thereby fix the charge-controlling resin on the surfaces of the toner base particles.
    Type: Grant
    Filed: January 31, 2008
    Date of Patent: June 14, 2011
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Masateru Kawamura, Jun Ikami
  • Publication number: 20100248115
    Abstract: Provided is a method for producing a toner having excellent particle size distribution and storage stability. The method set forth in the present specification is a method for producing a toner by aggregating and fusing base microparticles whose main component is a binder resin including anionic groups, wherein an aggregate is produced by aggregating the base microparticles in a base microparticle suspension, in a presence of a non-ionic surfactant such that a surface tension of an aqueous solution thereof is not lower than 45 mN/m at any concentration at or above a critical micelle concentration, and the toner is produced through fusion of the aggregate. According to this method, drops in a glass transition temperature of the toner can be curbed, and the toner having excellent storage stability and good particle size distribution can be obtained.
    Type: Application
    Filed: March 30, 2010
    Publication date: September 30, 2010
    Applicant: BROTHER KOGYO KABUSHIKI KAISHA
    Inventors: Jun IKAMI, Masateru KAWAMURA, Yasutomo IMAI
  • Patent number: 7642033
    Abstract: In a toner production method, a volatile solvent gas is jetted into a dispersion of aggregated resin particles where at least resin particles dispersed in a continuous phase are aggregated. A form of the aggregated resin particles is controlled by jetting the volatile solvent gas into the dispersion of aggregated resin particles. The volatile solvent is removed from the form-controlled aggregated resin particles.
    Type: Grant
    Filed: February 16, 2006
    Date of Patent: January 5, 2010
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Jun Ikami, Masateru Kawamura
  • Publication number: 20090325101
    Abstract: The present teachings provide a method for producing a yet superior toner by emulsification aggregation. The method for producing toner by emulsification aggregation comprises the following steps (a) and (b): (a) preparing primary base particles through aggregation and fusion of base microparticles obtained by emulsifying and dispersing a binder resin of the toner; and (b) producing secondary base particles by aggregating the primary base particles with the base microparticles.
    Type: Application
    Filed: June 10, 2009
    Publication date: December 31, 2009
    Applicant: Brother Kogyo Kabushiki Kaisha
    Inventors: Jun Ikami, Masateru Kawamura, Kazutoshi Kotama
  • Publication number: 20090246681
    Abstract: The present teaching provides a method for producing a positive charging toner that can exhibit stable charge characteristics. According to the present teaching, a positive charging toner is produced by preparing a base particle suspension having a conductivity not higher than 70 ?S/cm and comprising base particles that are obtained by mixing and emulsifying an aqueous medium and a resin solution containing the polyester resin; producing toner base particles by mixing the base particle suspension with a charge control resin microparticle suspension containing charge control resin microparticles; causing the charge control resin microparticles to adhere to the surfaces of the base particles; and washing the toner base particles.
    Type: Application
    Filed: March 31, 2009
    Publication date: October 1, 2009
    Applicant: Brother Kogyo Kabushiki Kaisha
    Inventors: Masateru KAWAMURA, Yasutomo Imai
  • Publication number: 20090191477
    Abstract: Provided is a method for producing a toner including the steps of: preparing a resin liquid by mixing at least a binder resin made of polyester resin and a colorant with an ester organic solvent represented by the following general formula (1); dispersing the resin liquid in an aqueous medium to form an emulsion; and removing the ester organic solvent from the emulsion to produce a toner, in which the ester organic solvent before the preparation of the resin liquid contains water in an amount of not less than 1% by weight and up to the saturation solubility at 25° C. to the ester organic solvent. (in which R1 is a hydrogen atom or a methyl group, and R2 is an alkyl group having 1 to 4 carbon atoms).
    Type: Application
    Filed: January 22, 2009
    Publication date: July 30, 2009
    Applicant: Brother Kogyo Kabushiki Kaisha
    Inventors: Masateru KAWAMURA, Jun IKAMI, Takanori UNO, Tomoaki HATTORI
  • Patent number: 7553600
    Abstract: Methods are described for rendering toner particles that are capable of being sufficiently and uniformly charged. The particles may be positively chargeable, non-magnetic, single component toner particles. At least one production method includes emulsifying a charge-controlling agent formed of a synthetic resin in an aqueous medium, the charge-controlling agent having been dissolved in or swollen with an organic solvent; removing the organic solvent; mixing with a suspension of toner base particles containing a binder and a colorant; and heating to fix the charge-controlling agent on the surfaces of the toner base particles. According to at least one method, a positively chargeable non-magnetic single component toner can be produced such that the amount of the charge-controlling agent deposited on the surfaces of the toner base particles falls within a range of 0.2 to 3.0 wt. %, with respect to the total weight of the toner.
    Type: Grant
    Filed: September 21, 2006
    Date of Patent: June 30, 2009
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Masateru Kawamura, Jun Ikami
  • Publication number: 20090123866
    Abstract: A method for producing toner is described. In the method for producing a toner, a resin liquid is prepared by mixing at least a binder resin made of polyester resin and a colorant with an organic solvent, the resin liquid is dispersed in an aqueous medium to form an emulsion, and the organic solvent is removed from the emulsion to produce a toner. The organic solvent before preparation of the resin liquid contains 5 to 20 parts by weight of water per 100 parts by weight of the organic solvent.
    Type: Application
    Filed: November 10, 2008
    Publication date: May 14, 2009
    Applicant: BROTHER KOGYO KABUSHIKI KAISHA
    Inventors: Masateru KAWAMURA, Jun IKAMI, Takanori UNO, Tomoaki HATTORI
  • Publication number: 20080292362
    Abstract: A developing apparatus is described. The developing apparatus includes a transport member including a plurality of electrodes forming a traveling wave electric field by successively applied voltages and a casing storing a toner transported by the transport member, wherein the activity of the toner based on the following measuring method shown in (1) to (3) is not more than 2.
    Type: Application
    Filed: April 30, 2008
    Publication date: November 27, 2008
    Applicant: BROTHER KOGYO KABUSHIKI KAISHA
    Inventors: Jun Ikami, Masateru Kawamura
  • Publication number: 20080286674
    Abstract: A method for producing a toner is described. The method for producing a toner may include the steps of: preparing a resin solution by mixing a binder resin, a colorant and a wax into an organic solvent; preparing an emulsion by heating the resin solution and an aqueous medium to a temperature of not less than a level allowing the wax to dissolve and less than the boiling point of the organic solvent, and mixing the resin solution and the aqueous medium with each other; and preparing a suspension by removing the organic solvent from the emulsion, and aggregating and fusing the suspension.
    Type: Application
    Filed: May 16, 2008
    Publication date: November 20, 2008
    Applicant: BROTHER KOGYO KABUSHIKI KAISHA
    Inventors: Masateru Kawamura, Jun Ikami
  • Publication number: 20080182198
    Abstract: A method for producing a positively chargeable toner is described. The method for producing a positively chargeable toner may include the steps of: mixing and emulsifying a charge-controlling resin having a positive polar group, an organic solvent and an aqueous medium to form an emulsion, and then removing the organic solvent from the emulsion, to thereby form a suspension of the charge-controlling resin having a positive polar group in the range of 5.0×10?5 to 6.0×10?4 mol/g; mixing the suspension of the charge-controlling agent with a suspension of toner base particles containing a binder resin and a colorant, to thereby form a mixture; and heating the mixture containing the suspension of the toner base particles and the suspension of the charge-controlling resin, to thereby fix the charge-controlling resin on the surfaces of the toner base particles.
    Type: Application
    Filed: January 31, 2008
    Publication date: July 31, 2008
    Applicant: BROTHER KOGYO KABUSHIKI KAISHA
    Inventors: Masateru KAWAMURA, Jun IKAMI
  • Patent number: 7344819
    Abstract: A method for manufacturing toner includes combining a polymer resin and an organic solvent to obtain an oil-based solvent; combining a dispersion stabilizer with water to obtain a water-based solvent; adding an amphiphilic solvent to the water-based solvent; emulsifying the oil-based solvent in the water-based solvent to form emulsion particles; and removing the organic solvent from the emulsion particles.
    Type: Grant
    Filed: November 24, 2004
    Date of Patent: March 18, 2008
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Jun Ikami, Masateru Kawamura
  • Patent number: 7280786
    Abstract: An electrostatic developing toner which can effectively suppress image fogging*1 by setting a ratio (d/D) of the average particle diameter D of the toner and the average particle diameter d of iron oxide particles contained in the toner as a colorant to within a predetermined range, and by setting the value of a ratio (?r/?s) between the residual magnetization ?r and saturation magnetization ?s of the iron oxide particles to a predetermined value or less, is provided. The value of the ratio (d/D) of the average particle diameter D of the toner and the average particle diameter d of iron oxide particles contained in the toner as a colorant is set to within the range of 0.01-0.03, and the value of the ratio (?r/?s) between the residual magnetization ?r and saturation magnetization ?s of the iron oxide particles is set to 0.3 or less.
    Type: Grant
    Filed: January 3, 2006
    Date of Patent: October 9, 2007
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Jun Ikami, Masateru Kawamura