Patents by Inventor Tahei Ishiwatari

Tahei Ishiwatari 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: 7187893
    Abstract: A recording medium carrier system of an image forming apparatus is constituted by independent units as a paper supply cassette, a paper feed unit, a transfer unit, a fixing unit, and a paper ejecting unit. An intermediate transfer unit in the transfer unit is provided with an intermediate transfer belt to which a toner image formed on a photoconductive drum is primarily transferred at a primary transfer position and which secondarily transfers the toner image on a recording medium at a secondary transfer position, and a driving roller for circulating the intermediate transfer belt. The primary transfer position is arranged close to the driving roller.
    Type: Grant
    Filed: May 6, 2002
    Date of Patent: March 6, 2007
    Assignee: Seiko Epson Corporation
    Inventors: Toshiya Takahata, Akira Kubota, Tatsuro Osawa, Nobumasa Abe, Takehiko Okamura, Hiroshi Ito, Tahei Ishiwatari, Toshihiko Yamazaki
  • Patent number: 7105262
    Abstract: The invention provides a liquid developer that is used in an apparatus for forming an image by developing an electrostatic latent image formed on a latent image carrying member, transferring the developed image to a recording medium, and then fixing the image, in which the liquid developer contains a carrier liquid and particles formed with a composition containing a binder resin, a colorant, and a charge controlling agent comprising a charge controlling substance containing an ionic or neutral substance, wherein the charge controlling substance containing an ionic or neutral substance is supported by an inorganic porous material.
    Type: Grant
    Filed: January 5, 2004
    Date of Patent: September 12, 2006
    Assignee: Seiko Epson Corporation
    Inventors: Hidehiro Takano, Tahei Ishiwatari, Takuya Kadota, Rie Miyazaki
  • Patent number: 7018766
    Abstract: The invention provides a toner comprising a binder resin, a colorant, and a charge control agent comprising a charge control substance supported by an inorganic porous material, and having been subjected to thermal fairing treatment. Also disclosed are a toner obtained by a process comprising the steps of: kneading a composition containing a binder resin, a colorant and a charge control agent comprising an ionic or neutral substance supported by an inorganic porous material; pulverizing the kneaded product; adding the pulverized product to a solvent immiscible with water; dispersing the mixture in an aqueous medium; and removing the solvent by at least one of heating and pressure reduction, and a toner comprising associated particles formed from: primary particles obtained from an emulsion of a binder resin; a colorant; and a charge control agent comprising a water soluble charge control substance incorporated in inorganic fine particles.
    Type: Grant
    Filed: November 6, 2003
    Date of Patent: March 28, 2006
    Assignee: Seiko Epson Corporation
    Inventors: Hidehiro Takano, Tahei Ishiwatari, Takuya Kadota, Rie Miyazaki
  • Patent number: 6957032
    Abstract: A recording medium carrier system of an image forming apparatus is constituted by independent units as a paper supply cassette, a paper feed unit, a transfer unit, a fixing unit, and a paper ejecting unit. An intermediate transfer unit in the transfer unit is provided with an intermediate transfer belt to which a toner image formed on a photoconductive drum is primarily transferred at a primary transfer position and which secondarily transfers the toner image on a recording medium at a secondary transfer position, and a driving roller for circulating the intermediate transfer belt. The primary transfer position is arranged close to the driving roller.
    Type: Grant
    Filed: May 6, 2002
    Date of Patent: October 18, 2005
    Assignee: Seiko Epson Corporation
    Inventors: Toshiya Takahata, Akira Kubota, Tatsuro Osawa, Nobumasa Abe, Takehiko Okamura, Hiroshi Ito, Tahei Ishiwatari, Toshihiko Yamazaki
  • Patent number: 6856782
    Abstract: A recording medium carrier system of an image forming apparatus is constituted by independent units as a paper supply cassette, a paper feed unit, a transfer unit, a fixing unit, and a paper ejecting unit. An intermediate transfer unit in the transfer unit is provided with an intermediate transfer belt to which a toner image formed on a photoconductive drum is primarily transferred at a primary transfer position and which secondarily transfers the toner image on a recording medium at a secondary transfer position, and a driving roller for circulating the intermediate transfer belt. The primary transfer position is arranged close to the driving roller.
    Type: Grant
    Filed: August 22, 2002
    Date of Patent: February 15, 2005
    Assignee: Seiko Epson Corporation
    Inventors: Toshiya Takahata, Akira Kubota, Tatsuro Osawa, Nobumasa Abe, Takehiko Okamura, Hiroshi Ito, Tahei Ishiwatari, Toshihiko Yamazaki
  • Publication number: 20050003293
    Abstract: The invention provides a liquid developer that is used in an apparatus for forming an image by developing an electrostatic latent image formed on a latent image carrying member, transferring the developed image to a recording medium, and then fixing the image, in which the liquid developer contains a carrier liquid and particles formed with a composition containing a binder resin, a colorant, and a charge controlling agent comprising a charge controlling substance containing an ionic or neutral substance, wherein the charge controlling substance containing an ionic or neutral substance is supported by an inorganic porous material.
    Type: Application
    Filed: January 5, 2004
    Publication date: January 6, 2005
    Inventors: Hidehiro Takano, Tahei Ishiwatari, Takuya Kadota, Rie Miyazaki
  • Patent number: 6792236
    Abstract: A recording medium having a toner image formed thereon is moved to pass through a press contact portion between an endless belt being heated and an pressure roller pressed against the endless belt. When passing through the press contact portion, the toner image is fused and permanently affixed onto the recording medium. An oil application width O of an oil application roller is shorter than belt width B of the endless belt, and a maximum passing width P of a recording medium that may be supplied for the image formation, but is longer than a maximum image-forming width I within which an image may be formed on the recording medium.
    Type: Grant
    Filed: August 8, 2002
    Date of Patent: September 14, 2004
    Assignee: Seiko Epson Corporation
    Inventors: Kaneo Yoda, Kazutoshi Fujisawa, Naoyuki Okumura, Tahei Ishiwatari, Hiroshi Tanaka, Kenjiro Yoshioka
  • Publication number: 20040143036
    Abstract: The invention provides a toner comprising a binder resin, a colorant, and a charge control agent comprising a charge control substance supported by an inorganic porous material, and having been subjected to thermal fairing treatment. Also disclosed are a toner obtained by a process comprising the steps of: kneading a composition containing a binder resin, a colorant and a charge control agent comprising an ionic or neutral substance supported by an inorganic porous material; pulverizing the kneaded product; adding the pulverized product to a solvent immiscible with water; dispersing the mixture in an aqueous medium; and removing the solvent by at least one of heating and pressure reduction, and a toner comprising associated particles formed from: primary particles obtained from an emulsion of a binder resin; a colorant; and a charge control agent comprising a water soluble charge control substance incorporated in inorganic fine particles.
    Type: Application
    Filed: November 6, 2003
    Publication date: July 22, 2004
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hidehiro Takano, Tahei Ishiwatari, Takuya Kadota, Rie Miyazaki
  • Patent number: 6731899
    Abstract: A recording medium carrier system of an image forming apparatus is constituted by independent units as a paper supply cassette, a paper feed unit, a transfer unit, a fixing unit, and a paper ejecting unit. An intermediate transfer unit in the transfer unit is provided with an intermediate transfer belt to which a toner image formed on a photoconductive drum is primarily transferred at a primary transfer position and which secondarily transfers the toner image on a recording medium at a secondary transfer position, and a driving roller for circulating the intermediate transfer belt. The primary transfer position is arranged close to the driving roller.
    Type: Grant
    Filed: May 6, 2002
    Date of Patent: May 4, 2004
    Assignee: Seiko Epson Corporation
    Inventors: Toshiya Takahata, Akira Kubota, Tatsuro Osawa, Nobumasa Abe, Takehiko Okamura, Hiroshi Ito, Tahei Ishiwatari, Toshihiko Yamazaki
  • Publication number: 20040028431
    Abstract: A recording medium carrier system of an image forming apparatus is constituted by independent units as a paper supply cassette, a paper feed unit, a transfer unit, a fixing unit, and a paper ejecting unit. An intermediate transfer unit in the transfer unit is provided with an intermediate transfer belt to which a toner image formed on a photoconductive drum is primarily transferred at a primary transfer position and which secondarily transfers the toner image on a recording medium at a secondary transfer position, and a driving roller for circulating the intermediate transfer belt. The primary transfer position is arranged close to the driving roller.
    Type: Application
    Filed: May 6, 2002
    Publication date: February 12, 2004
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Toshiya Takahata, Akira Kubota, Tatsuro Osawa, Nobumasa Abe, Takehiko Okamura, Hiroshi Ito, Tahei Ishiwatari, Toshihiko Yamazaki
  • Publication number: 20030113142
    Abstract: A recording medium having a toner image formed thereon is moved to pass through a press contact portion between an endless belt being heated and an pressure roller pressed against the endless belt. When passing through the press contact portion, the toner image is fused and permanently affixed onto the recording medium. An oil application width O of an oil application roller is shorter than belt width B of the endless belt, and a maximum passing width P of a recording medium that may be supplied for the image formation, but is longer than a maximum image-forming width I within which an image may be formed on the recording medium.
    Type: Application
    Filed: August 8, 2002
    Publication date: June 19, 2003
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Kaneo Yoda, Kazutoshi Fujisawa, Naoyuki Okumura, Tahei Ishiwatari, Hiroshi Tanaka, Kenjiro Yoshioka
  • Publication number: 20030077091
    Abstract: A recording medium carrier system of an image forming apparatus is constituted by independent units as a paper supply cassette, a paper feed unit, a transfer unit, a fixing unit, and a paper ejecting unit. An intermediate transfer unit in the transfer unit is provided with an intermediate transfer belt to which a toner image formed on a photoconductive drum is primarily transferred at a primary transfer position and which secondarily transfers the toner image on a recording medium at a secondary transfer position, and a driving roller for circulating the intermediate transfer belt. The primary transfer position is arranged close to the driving roller.
    Type: Application
    Filed: August 22, 2002
    Publication date: April 24, 2003
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Toshiya Takahata, Akira Kubota, Tatsuro Osawa, Nobumasa Abe, Takehiko Okamura, Hiroshi Ito, Tahei Ishiwatari, Toshihiko Yamazaki
  • Publication number: 20030035664
    Abstract: A recording medium carrier system of an image forming apparatus is constituted by independent units as a paper supply cassette, a paper feed unit, a transfer unit, a fixing unit, and a paper ejecting unit. An intermediate transfer unit in the transfer unit is provided with an intermediate transfer belt to which a toner image formed on a photoconductive drum is primarily transferred at a primary transfer position and which secondarily transfers the toner image on a recording medium at a secondary transfer position, and a driving roller for circulating the intermediate transfer belt. The primary transfer position is arranged close to the driving roller.
    Type: Application
    Filed: May 6, 2002
    Publication date: February 20, 2003
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Toshiya Takahata, Akira Kubota, Tatsuro Osawa, Nobumasa Abe, Takehiko Okamura, Hiroshi Ito, Tahei Ishiwatari, Toshihiko Yamazaki
  • Publication number: 20020181976
    Abstract: A recording medium carrier system of an image forming apparatus is constituted by independent units as a paper supply cassette, a paper feed unit, a transfer unit, a fixing unit, and a paper ejecting unit. An intermediate transfer unit in the transfer unit is provided with an intermediate transfer belt to which a toner image formed on a photoconductive drum is primarily transferred at a primary transfer position and which secondarily transfers the toner image on a recording medium at a secondary transfer position, and a driving roller for circulating the intermediate transfer belt. The primary transfer position is arranged close to the, driving roller.
    Type: Application
    Filed: May 6, 2002
    Publication date: December 5, 2002
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Toshiya Takahata, Akira Kubota, Tatsuro Osawa, Nobumasa Abe, Takehiko Okamura, Hiroshi Ito, Tahei Ishiwatari, Toshihiko Yamazaki
  • Patent number: 6459877
    Abstract: A recording medium having a toner image formed thereon is moved to pass through a press contact portion between an endless belt being heated and an pressure roller pressed against the endless belt. When passing through the press contact portion, the toner image is fused and permanently affixed onto the recording medium. An oil application width O of an oil application roller is shorter than belt width B of the endless belt, and a maximum passing width P of a recording medium that may be supplied for the image formation, but is longer than a maximum image-forming width I within which an image may be formed on the recording medium.
    Type: Grant
    Filed: January 19, 2000
    Date of Patent: October 1, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Kaneo Yoda, Kazutoshi Fujisawa, Naoyuki Okumura, Tahei Ishiwatari, Hiroshi Tanaka, Kenjiro Yoshioka
  • Patent number: 6408158
    Abstract: A recording medium carrier system of an image forming apparatus is constituted by independent units as a paper supply cassette, a paper feed unit, a transfer unit, a fixing unit, and a paper ejecting unit. An intermediate transfer unit in the transfer unit is provided with an intermediate transfer belt to which a toner image formed on a photoconductive drum is primarily transferred at a primary transfer position and which secondarily transfers the toner image on a recording medium at a secondary transfer position, and a driving roller for circulating the intermediate transfer belt. The primary transfer position is arranged close to the driving roller.
    Type: Grant
    Filed: November 22, 2000
    Date of Patent: June 18, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Toshiya Takahata, Akira Kubota, Tatsuro Osawa, Nobumasa Abe, Takehiko Okamura, Hiroshi Ito, Tahei Ishiwatari, Toshihiko Yamazaki
  • Patent number: 6336022
    Abstract: A developing unit of the present invention includes a case which accommodates toner containing pigment, a developing roller, a supply roller formed of an elastic member arranged to be pressed against a surface of the developing roller in such a manner as to supply toner to the surface of the developing roller.
    Type: Grant
    Filed: January 5, 2001
    Date of Patent: January 1, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Kazuhiro Ichikawa, Yoshihiro Nakashima, Hidenori Kin, Tomoe Aruga, Yoichi Yamada, Yukio Takayama, Tahei Ishiwatari
  • Patent number: 6312788
    Abstract: An image is formed in a receiving sheet by embedding toner in an image receiving layer on a base. The distribution of molecular weight of resin in the image receiving layer measured by gel permeation chromatography (GPC) of soluble matters of tetrahydrofuran (THF) has at least two peaks or shoulders. And the critical surface tension of the image receiving layer is made to be smaller than the critical surface tension of external additive. Further, the image receiving layer has a thermal characteristic such that a storage modulus (G′) of 1×102 Pa to 1×105 Pa and a loss modulus (G″) of 1×102 Pa to 1×105 Pa at temperatures at which the toner is fixed. Furthermore, the image receiving layer contains an aromatic ester compound, more preferably the aromatic polyester compound being dialkyl phthalate. Still further, the image receiving layer has a Rockwell hardness (R scale) HRa of 121 or lower.
    Type: Grant
    Filed: May 22, 1997
    Date of Patent: November 6, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Shuhei Mohri, Tahei Ishiwatari, Masanao Kunugi
  • Patent number: 6295433
    Abstract: A developing unit of the present invention includes a case which accommodates toner containing pigment, a developing roller, a supply roller formed of an elastic member arranged to be pressed against a surface of the developing roller in such a manner as to supply toner to the surface of the developing roller. A conveying fin is supported by the case so as to convey toner to the surface of the supply roller wherein the developing roller, the supply roller, and the conveying fin are sequentially disposed in a horizontal direction. The number of revolutions of the conveying fin per unit time is between {fraction (1/50)} and {fraction (1/20)} of the supply roller.
    Type: Grant
    Filed: August 9, 1999
    Date of Patent: September 25, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Kazuhiro Ichikawa, Yoshihiro Nakashima, Hidenori Kin, Tomoe Aruga, Yoichi Yamada, Yukio Takayama, Tahei Ishiwatari
  • Publication number: 20010005461
    Abstract: A developing unit of the present invention includes a case which accommodates toner containing pigment, a developing roller, a supply roller having chamfered ends and formed of an elastic member arranged to be pressed against a surface of the developing roller in such a manner as to supply toner to the surface of the developing roller. Moreover, the ratio or open cells in the elastic supply roller is made to be 30% or higher and depth of engagement of the supply roller to the developing roller is made to be 0.4 mm or smaller. Also a first sealing member is disposed on the side ends of the developing roller and supply roller so as to prevent leakage to the outside portion of the case. The side surfaces of the developing roller have a surface roughness of 0.5 &mgr;m or smaller in Rmax.
    Type: Application
    Filed: January 5, 2001
    Publication date: June 28, 2001
    Inventors: Kazuhiro Ichikawa, Yoshihiro Nakashima, Hidenori Kin, Tomoe Aruga, Yoichi Yamada, Yukio Takayama, Tahei Ishiwatari