Patents by Inventor Ken Ohmura

Ken Ohmura 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: 6921616
    Abstract: A color image forming method is disclosed. The following steps are repeated; the steps for forming a latent image on a photoreceptor and developing the latent image by a developer to form a color toner image on the photoreceptor; collectively transferring the color toner image onto an image support; and fixing the transferred toner image; and a toner having a variation coefficient of the shape coefficient of not more than 16% and the number variation coefficient in the number particle diameter distribution of not more than 27% is employed.
    Type: Grant
    Filed: May 30, 2003
    Date of Patent: July 26, 2005
    Assignee: Konica Corporation
    Inventors: Hiroshi Yamazaki, Hiroyuki Yamada, Ken Ohmura
  • Patent number: 6921619
    Abstract: An electrostatic image developing toner is disclosed. The toner has a domain-matrix structure; the average of the horizontal FERE diameter of the part corresponding to said domain is from 200 to 900 nm; and the variation coefficient of said horizontal FERE diameter is 40 percent or less.
    Type: Grant
    Filed: January 16, 2002
    Date of Patent: July 26, 2005
    Assignee: Konica Corporation
    Inventors: Ken Ohmura, Asao Matsushima, Hiroshi Yamazaki, Yoshiki Nishimori, Hiroyuki Yamada, Shiro Hirano
  • Publication number: 20050158647
    Abstract: In a toner for developing electrostatic latent images, average circularity is 0.94-0.98, the average value of the equivalent circular diameter is 2.6-7.4 ?m and the gradient of the circularity to the equivalent circular diameter is from ?0.005 to ?0.001, and an image forming method using the same.
    Type: Application
    Filed: January 20, 2004
    Publication date: July 21, 2005
    Applicant: Konica Minolta Holdings, Inc.
    Inventors: Ken Ohmura, Hiroshi Yamazaki, Asao Matsushima, Shiro Hirano
  • Publication number: 20050095516
    Abstract: An image forming method, including the steps of: charging each surface of a plurality of amorphous-silicon-based photoreceptors; exposing the each surface of the amorphous-silicon-based photoreceptors to form respective color latent images of yellow, magenta, cyan and black; developing the respective color latent images with corresponding color toners to form respective color visible toner images; and transferring the respective color toner images successively to be piled up on a toner image receiving member, wherein the color toner of each color contains grains having volume average grain size (D4) of 3-7 ?m and number average primary grain size of 40-800 nm, and the relationship of 1.04?B/A?1.4 (6?A?30) is satisfied between an exposure size (A ?m) in the main scanning direction in the exposing step and a development size (B ?m) corresponding to the exposure size (A ?m) in the developing step.
    Type: Application
    Filed: July 22, 2004
    Publication date: May 5, 2005
    Applicant: KONICA MINOLTA BUSINESS TECHNOLOGIES, INC.
    Inventors: Ken Ohmura, Hiroshi Yamazaki
  • Patent number: 6884555
    Abstract: An electrostatic image developing toner is disclosed. The toner is composed of a colored particle containing a compound represented by Formula (1).
    Type: Grant
    Filed: April 3, 2003
    Date of Patent: April 26, 2005
    Assignee: Konica Corporation
    Inventors: Tomoe Kitani, Hiroshi Yamazaki, Ken Ohmura
  • Publication number: 20050069802
    Abstract: A toner for electrostatic latent image development contains a toner particle having a median diameter (d50) in number standard of 2.5 ?m to 7.5 ?m, acrylate of less than 12 ppm and aliphatic alcohol of 4 to 12 carbons of 40 ppm to 300 ppm.
    Type: Application
    Filed: September 27, 2004
    Publication date: March 31, 2005
    Applicant: Konica Minolta Business Technologies, Inc.
    Inventors: Naohiro Hirose, Ken Ohmura, Meizo Shirose
  • Publication number: 20050014084
    Abstract: A method for producing a toner comprising the step of coagulating at least one crystalline ester compound represented by Formula 1 and resin particles in an aqueous medium in the presence of and aluminum compound. R1—(OCO—R2)n ??Formula 1 In the formula, R1 and R2 are each a carbon hydride group having from 1 to 40 carbon atoms which may have a substituent and n is an integer of from 1 to 4.
    Type: Application
    Filed: March 18, 2004
    Publication date: January 20, 2005
    Applicant: Konica Minolta Business Technologies, Inc.
    Inventors: Ken Ohmura, Hiroshi Yamazaki
  • Patent number: 6844126
    Abstract: An electrostatic latent image developing toner is disclosed. The toner particles has an average of circularity of 0.94 to 0.98; an average of circle equivalent diameter of 2.6 to 7.4 ?m; and gradient of the circularity with respect to the circle-equivalent diameter of ?0.050 to ?0.010.
    Type: Grant
    Filed: December 4, 2002
    Date of Patent: January 18, 2005
    Assignee: Konica Corporation
    Inventors: Ken Ohmura, Asao Matsushima, Shiro Hirano, Hiroshi Yamazaki
  • Publication number: 20040265719
    Abstract: An electrostatic charge image developing toner having: a toner particle having a colorant and a resin; and a surfactant having two or more anionic groups within one molecule in an amount of 10 ppm to 10,000 ppm.
    Type: Application
    Filed: March 8, 2004
    Publication date: December 30, 2004
    Applicant: Konica Minolta Business Technologies, Inc.
    Inventors: Asao Matsushima, Shiro Hirano, Naohiro Hirose, Ken Ohmura
  • Patent number: 6821695
    Abstract: A toner for forming an electrophotographic image is disclosed. The toner particle contains at least two inorganic salts including an inorganic salt comprising a positive ion having a first valence and an inorganic salt comprising a positive ion having a second valence different from the first valence, a total amount of the inorganic salt having the first valence is greatest among the inorganic salts in the toner particle, and a total amount of the inorganic salt having the second valence is second greatest among the inorganic salts in the toner particle.
    Type: Grant
    Filed: August 20, 2002
    Date of Patent: November 23, 2004
    Assignee: Konica Corporation
    Inventors: Asao Matsushima, Ken Ohmura, Takao Yamanouchi, Naohiro Hirose, Tomoe Kitani, Yoshiki Nishimori
  • Patent number: 6811941
    Abstract: Disclosed is an electrostatic image developing toner comprising a coloring agent and toner particles, said toner particles have a matrix-domain structure, and the average of the area of a Voronoi polygon formed by the perpendicular bisecting line between the centers of gravity of domains adjacent to each other in said matrix-domain structure is from 20,000 to 120,000 nm2, and the variation coefficient of the area of said Voronoi polygon is less than or equal to 25 percent. Color image having, particularly good transparency and excellent color difference, can be obtained by the toner which is not affected by a residual material present on the surface of toner particles and does not result in variation of the amount of static charge at high temperature as well as at high humidity or after long leaving without operation.
    Type: Grant
    Filed: July 22, 2002
    Date of Patent: November 2, 2004
    Assignee: Konica Corporation
    Inventors: Kazuhisa Horiuchi, Tatsuya Nagase, Meizo Shirose, Hiroshi Yamazaki, Hiroyuki Yamada, Ken Ohmura, Asao Matsushima, Shiro Hirano, Yoshiki Nishimori
  • Patent number: 6808853
    Abstract: An electrostatic image developing toner comprising a resin and a colorant is disclosed. The resin comprises a polymerization component of a polymerizable monomer having a polar group in an amount of 1.0 to 10.0 percent by weight, and a polymerization component of a polyfunctional polymerizable monomer in an amount of 0.1 to 10.0 percent by weight; ratio (A/B) is from 0.5 to 20.0 percent; and either a peak or a shoulder is positioned in the molecular weight region of 5,000 to 20,000, wherein A is an area of a chromatograph curve in the molecular weight region of 60,000 to 1,000,000, based on GCP measurement of a THF soluble component of toner and B is an entire area of the chromatograph curve.
    Type: Grant
    Filed: December 2, 2002
    Date of Patent: October 26, 2004
    Assignee: Konica Corporation
    Inventors: Tomoe Kitani, Takao Yamanouchi, Naohiro Hirose, Ken Ohmura
  • Publication number: 20040209183
    Abstract: An image forming method in which toner having a an average circularity of 0.94-0.99, and an average equivalent circle diameter of 2.6-7.4 &mgr;m of toner particles is utilized, an electrostatic latent image formed on an image is transferred on a transferring material followed by fixing, wherein non-transferred toner remaining on said image carrying member is collected for reuse for image formation, and non-transferred toner collected is utilized after having been passed through a toner intermediate chamber.
    Type: Application
    Filed: March 2, 2004
    Publication date: October 21, 2004
    Applicant: Konica Minolta Holdings, Inc.
    Inventors: Ken Ohmura, Hiroshi Yamazaki, Asao Matsushima, Eiichi Yoshida
  • Patent number: 6806012
    Abstract: An electrostatic image developing toner is disclosed. The resin of the toner particle has a cell structure and an average value of FERE-horizontal diameters of the cells is from 20 to 200 nm and a variation coefficient of the FERE-horizontal diameters of the cells is from 10 to 35%.
    Type: Grant
    Filed: September 16, 2002
    Date of Patent: October 19, 2004
    Assignee: Konica Corporation
    Inventors: Yasuko Yamauchi, Ken Ohmura, Masafumi Uchida
  • Publication number: 20040197692
    Abstract: A toner for developing an electrostatic image is disclosed. The toner comprises toner particles comprising a resin and a colorant, and the toner comprises metal oxide particles have a domain-matrix structure comprising a domain and a matrix.
    Type: Application
    Filed: March 22, 2004
    Publication date: October 7, 2004
    Applicant: Konica Minolta Holdings, Inc.
    Inventors: Kenji Yamane, Ken Ohmura, Yasuko Yamauchi
  • Publication number: 20040175639
    Abstract: A toner for developing an electrstatic image is disclosed. The toner particles containing a binder resin containing a polyester resin or a polyol resin and a colorant, and the toner particles contain aluminum in an amount of 0.007 to 0.140% by weight, chlorine in an amount of 0.002 to 0.412% by weight, and the toner particles have an average circular degree of 0.94 to 0.99 and an average circle equivalent diameter of from 2.6 to 7.4 &mgr;m.
    Type: Application
    Filed: February 26, 2004
    Publication date: September 9, 2004
    Applicant: Konica Minolta Holdings, Inc.
    Inventors: Asao Matsushima, Hiroshi Yamazaki, Ken Ohmura, Eiichi Yoshida
  • Patent number: 6753122
    Abstract: A toner for forming a color image comprises chromatic toners and a black toner is disclosed. Each of the toners is produced by polymerization of a polymerizable monomer in an aqueous medium, the difference of re-dispersion electro-conductivity of each of the toners is within the range of from 0.8 to 12 &mgr;s/cm, the number of free colorant particles on the black toner surface is less than 9 per 500 toner particles, and a light absorbance at 500 nm of a black toner dispersion is nor more than 0.08.
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: June 22, 2004
    Assignee: Konica Corporation
    Inventors: Ken Ohmura, Ryuji Kitani, Yasuko Yamauchi, Kaori Soeda
  • Patent number: 6703177
    Abstract: An electrophotographic image forming method is disclosed. The method comprises forming a latent image on a static image carrier, developing the static image by a developer containing a toner, transferring the toner image onto another image carrier, transferring the toner image on the image carrier onto an image forming support, and fixing the toner image transferred on the image forming support, and the toner has a variation coefficient of the shape coefficient of not more than 16% and a number variation coefficient of the particle diameter distribution in number of not more than 27%, and the other image carrier is a cylindrical member having an electrode contacting to the interior surface thereof.
    Type: Grant
    Filed: April 19, 2002
    Date of Patent: March 9, 2004
    Assignee: Konica Corporation
    Inventors: Hiroshi Yamazaki, Ken Ohmura
  • Publication number: 20040043319
    Abstract: Disclosed is an electrostatic image developing toner comprising a coloring agent and toner particles, said toner particles have a matrix-domain structure, and the average of the area of a Voronoi polygon formed by the perpendicular bisecting line between the centers of gravity of domains adjacent to each other in said matrix-domain structure is from 20,000 to 120,000 mm2, and the variation coefficient of the area of said Voronoi polygon is less than or equal to 25 percent.
    Type: Application
    Filed: November 6, 2001
    Publication date: March 4, 2004
    Inventors: Kazuhisa Horiuchi, Tatsuya Nagase, Meizo Shirose, Hiroshi Yamazaki, Hiroyuki Yamada, Ken Ohmura, Asao Matsushima, Shiro Hirano, Yoshiki Nishimori
  • Patent number: 6689522
    Abstract: An image forming method, comprising steps of: forming a latent image on a photoreceptor having an electrically conductive support having thereon a charge generating layer and a charge transporting layer; developing the latent image with a developer containing a toner to form a toner image on the photoreceptor; and transferring the toner image onto an image receiving member, wherein the ratio of 50% volume particle diameter to 50% number particle diameter of the toner is within the range of 1.0 to 1.15, the ratio of the cumulative 75% volume particle diameter from the largest particle diameter to the cumulative 75% number particle diameter from the largest particle diameter of the toner is 1.0 to 1.20 and the number of toner particles having a particle diameter of not larger than 0.7×Dp50 is at most 10% of the number of all the toner particles in the toner.
    Type: Grant
    Filed: April 19, 2002
    Date of Patent: February 10, 2004
    Assignee: Konica Minolta Technosearch Co., Ltd.
    Inventors: Hiroshi Yamazaki, Ken Ohmura, Akihiko Itami, Meizo Shirose, Asao Matsushima, Hiroyuki Kozuru, Tomoko Tanma