Patents by Inventor Tsutomu Onuma

Tsutomu Onuma 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).

  • Publication number: 20030016955
    Abstract: A process cartridge which is detachably mountable to the main body of an image-forming apparatus has a photosensitive member, a toner-holding section and is provided with a toner-carrying member which holds therein a toner and is provided with a toner-carrying member which transports the toner to a developing zone, and a toner-residual detection means capable of detecting a toner residual by a change in electrostatic capacity which is caused between electrodes provided inside the toner-holding section. The toner contains at least a binder resin and a colorant, having a weight-average particle diameter of from 6.5 &mgr;m to 15.0 &mgr;m, and having a Carr's floodability index of more than 80.
    Type: Application
    Filed: April 25, 2002
    Publication date: January 23, 2003
    Applicant: Canon Kabushiki Kaisha
    Inventors: Kaori Hiratsuka, Hirohide Tanikawa, Tsutomu Onuma, Nobuyuki Okubo
  • Publication number: 20020182528
    Abstract: In a toner production process having at least a kneading step, a pulverization step using a mechanical grinding machine, and a classification step, the grinding means comprises a mechanical grinding machine having at least a rotor which is a rotator attached to the center rotating shaft and a stator which is provided around the rotor, keeping a constant gap between the stator and the rotor surface, the grinding machine being so constructed that a circular space formed by keeping the gap stands airtight, and the surface of at least one of the rotor and the stator is coated by the plating of a chromium alloy containing at least chromium carbide.
    Type: Application
    Filed: December 14, 2001
    Publication date: December 5, 2002
    Inventors: Tsuneo Nakanishi, Hirohide Tanikawa, Tsutomu Onuma, Nobuyuki Okubo, Kaori Hiratsuka
  • Patent number: 6458499
    Abstract: A toner is principally constituted by a binder resin, a colorant and a hydrocarbon wax. The hydrocarbon wax has a hydroxyl value (Hv) of 5-150 mgKOH/g and an ester value (Ev) of 1-50 mgKOH/g satisfying Hv>Ev. Further, the toner has a tetrahydrofuran-soluble content providing a gel-permeation chromatogram showing at least one peak in a molecular weight region of 3×103 to 5×104 and at least one peak or shoulder in a molecular weight region of 1×105 to 1×107.
    Type: Grant
    Filed: June 1, 2001
    Date of Patent: October 1, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tsutomu Onuma, Hirohide Tanikawa, Nobuyuki Okubo, Tsuneo Nakanishi, Katsuhisa Yamazaki, Kaori Hiratsuka
  • Patent number: 6426169
    Abstract: A toner having a stable chargeability in various environments, a stable fixability over a wide temperature range and a resistance to sticking on an image-bearing member, is formed of a binder resin, a colorant and an azo iron compound as a charge control agent. The azo iron compound is formed from a monoazo compound having at least one alkyl group and two hydroxyl groups capable of bonding with an iron atom. The toner has a tetrahydrofuran-soluble content providing a gel-permeation chromatogram showing at least one peak in a molecular weight region of 3×103 to 5×104 and at least one peak or shoulder in a molecular weight region of above 5×104 and at most 1×107.
    Type: Grant
    Filed: October 30, 2000
    Date of Patent: July 30, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tsutomu Onuma, Hirohide Tanikawa, Nobuyuki Okubo, Yoshihiro Ogawa, Tsuneo Nakanishi, Katsuhisa Yamazaki, Kaori Hiratsuka
  • Publication number: 20020051922
    Abstract: A dry magnetic toner is formed of magnetic toner particles comprising a binder resin and magnetic iron oxide particles. The magnetic toner is provided with excellent developing performances and transferability by controlling the presence of isolated iron-containing particles and containing a high percentage of spherical particles, the amount of which is controlled relative to the weight-average particle size of the magnetic toner and a content of particles of 3 &mgr;m or below in the magnetic toner.
    Type: Application
    Filed: July 25, 2001
    Publication date: May 2, 2002
    Inventors: Katsuhisa Yamazaki, Tsutomu Onuma, Nobuyuki Okubo, Tsuneo Nakanishi, Kaori Hiratsuka
  • Publication number: 20020034702
    Abstract: A toner is principally constituted by a binder resin, a colorant and a hydrocarbon wax. The hydrocarbon wax has a hydroxyl value (Hv) of 5-150 mgKOH/g and an ester value (Ev) of 1-50 mgKOH/g satisfying Hv>Ev. Further, the toner has a tetrahydrofuran-soluble content providing a gel-permeation chromatogram showing at least one peak in a molecular weight region of 3×103 to 5×104 and at least one peak or shoulder in a molecular weight region of 1×105 to 1×107.
    Type: Application
    Filed: June 1, 2001
    Publication date: March 21, 2002
    Inventors: Tsutomu Onuma, Hirohide Tanikawa, Nobuyuki Okubo, Tsuneo Nakanishi, Katsuhisa Yamazaki, Kaori Hiratsuka
  • Patent number: 6187496
    Abstract: A toner for developing an electrostatic image is formed of toner particles; wherein each toner particle includes (i) 100 wt. parts of a binder resin having a glass transition point (Tg) of 50-70° C., (ii) 0.2-20 wt. parts of solid wax, and (iii) colorant particles or magnetic powder, (iv) lubricant particles carrying a liquid lubricant, so that the toner particle retains at its surface the liquid lubricant gradually released from the particles (iv). The toner may be further blended with an organically treated inorganic fine powder to provide a developer. The toner or developer retains good lubricity and releasability so that it is suitable to be used in an image forming method including means contacting a latent image-bearing means, such as a contact charging means, a contact transfer means or a contact cleaning means.
    Type: Grant
    Filed: March 20, 1997
    Date of Patent: February 13, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hirohide Tanikawa, Toshiaki Nakahara, Keita Nozawa, Kazuyoshi Hagiwara, Minoru Shimojo, Rika Shinba, Masami Fujimoto, Tsutomu Onuma
  • Patent number: 6120961
    Abstract: A toner for developing an electrostatic image includes a binder resin, a colorant and a wax. The toner shows heat-absorption characteristics represented by a DSC heat-absorption curve obtained on temperature increase in a temperature range of 30-150.degree. C. by a differential scanning colorimeter (DSC). The DSC heat-absorption curve shows a maximum heat-absorption peak (P1) in a temperature range of 70-90.degree. C. The DSC curve also provides a differential curve showing a first maximum (Max1) on a lowest temperature side at a temperature (T1) of 50-65.degree. C., showing a second maximum (Max2) on a next lowest temperature side at a temperature (T2) of 65-85.degree. C., and showing a minimum (Min1) on a highest temperature side at a temperature (T3) of at least 95.degree. C. Because of the DSC heat-absorption characteristics, the toner exhibits excellent fixability (including anti-offset characteristic) over a wide temperature range and excellent continuous image forming characteristic.
    Type: Grant
    Filed: September 26, 1997
    Date of Patent: September 19, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hirohide Tanikawa, Masami Fujimoto, Tsutomu Onuma, Hiroyuki Fujikawa
  • Patent number: 6077638
    Abstract: A toner for developing an electrostatic image is formed of toner particles; wherein each toner particle includes (i) 100 wt. parts of a binder resin having a glass transition point (Tg) of 50-70.degree. C., (ii) 0.2-20 wt. parts of solid wax, and (iii) colorant particles or magnetic powder carrying a liquid lubricant, so that the toner particle retains at its surface the liquid lubricant gradually released from the particles (iii). The toner may be further blended with an organically treated inorganic fine powder to provide a developer. The toner or developer retains good lubricity and releasability so that it is suitable to be used in an image forming method including means contacting a latent image-bearing means, such as a contact charging means, a contact transfer means or a contact cleaning means.
    Type: Grant
    Filed: March 21, 1997
    Date of Patent: June 20, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hirohide Tanikawa, Toshiaki Nakahara, Keita Nozawa, Kazuyoshi Hagiwara, Minoru Shimojo, Rika Shinba, Masami Fujimoto, Tsutomu Onuma
  • Patent number: 6020102
    Abstract: A positive-chargeable toner is disclosed which has a binder resin, a colorant and a charge control agent. The binder resin contains a styrene copolymer and has an acid value of from 0.5 to 50.0 mg KOH/g, and the charge control agent has an imidazole derivative represented by the Formula (1). Also, an image forming method and an apparatus unit, making use of the positive-chargeable toner, are disclosed.
    Type: Grant
    Filed: July 2, 1998
    Date of Patent: February 1, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masami Fujimoto, Hirohide Tanikawa, Tsutomu Onuma, Hiroyuki Fujikawa
  • Patent number: 6007957
    Abstract: A magnetic toner includes magnetic toner particles containing at least a binder resin and a magnetic iron oxide. The magnetic iron oxide contains 0.2 to 4.0% by weight of at least one metal element selected from the group consisting of Mn, Zn, Ni, Cu, Co, Cr, Cd, Al, Sn and Mg, and 0.2 to 0.8% by weight of silicon element on the basis of an iron element; the ratio (B.sub.si /A.sub.Si).times.100 of the content B.sub.Si of the silicon element present in the magnetic iron oxide up to an iron element solubility of 20% by weight to the total content A.sub.Si of the silicon element present in the magnetic iron oxide is 45 to 85%; the ratio (C.sub.si /A.sub.Si).times.100 of the content C.sub.Si of the silicon element present in the magnetic iron oxide up to an iron element solubility of 10% by weight to the total content A.sub.Si is 35 to 70%; and the magnetic toner has a weight average particle diameter of 3.5 to 10.0 .mu.
    Type: Grant
    Filed: September 24, 1998
    Date of Patent: December 28, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takakuni Kobori, Tsutomu Onuma, Nobuyuki Okubo, Masaichiro Katada, Masao Takano
  • Patent number: 5977515
    Abstract: An underwater laser processing system has a laser torch; a laser torch driving mechanism for changing a laser emission position of the laser torch; and a chamber with one end opened to an external environment, which contains the laser torch; wherein a partitioning wall for preventing permeation of water is provided between a free end of the chamber and the laser torch. The system is used for detecting a sensitized portion and repairing it at one time using a sensitization detecting arrangement. Moreover, it is used for forming an alloying layer by melting a sprayed coating film, and for forming a new surface layer by emitting a laser beam through a solution containing a metal component.
    Type: Grant
    Filed: October 4, 1995
    Date of Patent: November 2, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Keiichi Uraki, Toshitaka Satsuta, Akira Onuma, Mitsuo Nakamura, Tsutomu Onuma, Toshimi Matsumoto, Yasumasa Tamai, Hiroshi Yamauchi, Eisaku Hayashi, Ren Morinaka
  • Patent number: 5968701
    Abstract: A toner exhibiting good fixing performances even at a high process speed is formed of a binder resin, a wax and a colorant. The toner is especially characterized by visco-elastic properties including: (a) a storage modulus G' (160.degree. C.) of 8.0.times.10.sup.2 -1.2.times.10.sup.4 Pa at 160.degree. C., (b) a loss modulus G" (160.degree. C.) of 4.0.times.10.sup.2 -6.0.times.10.sup.3 Pa at 160.degree. C., (c) a loss tangent tan.delta. (160.degree. C.)=G" (160.degree. C.)/G' (160.degree. C.) of 0.1-1.5 at 160.degree. C., (d) a storage modulus G' (190.degree. C.) of 6.0.times.10.sup.2 -1.6.times.10.sup.4 Pa at 190.degree. C., (e) a loss modulus G" (190.degree. C.) of 2.0.times.10.sup.2 -4.0.times.10.sup.3 Pa at 190.degree. C., (f) a yloss tangent tan.delta. (190.degree. C.)=G" (190.degree. C.)/G' (190.degree. C.) of 0.05-1.2 at 190.degree. C., (g) G' (160.degree. C.)/G' (190.degree. C.)=0.5-2.0, and (h) tan.delta. (160.degree. C.)>tan.delta. (190.degree. C.).
    Type: Grant
    Filed: December 23, 1998
    Date of Patent: October 19, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tsutomu Onuma, Hirohide Tanikawa, Masami Fujimoto, Hiroyuki Fujikawa
  • Patent number: 5938954
    Abstract: A submerged laser beam irradiation equipment provides a high quality submerged laser beam processing of a submerged workpiece using only a small amount of a gas. The submerged laser beam irradiation equipment has: a focus lens for focusing a laser beam; a mirror tube which houses the lens; a first nozzle operating to cover the front end of the mirror tube in an irradiating direction of the laser beam; a skirt portion provided at the front end of the first nozzle for preventing water intrusion thereinto; and a shutter mechanism operable to open and close and provided between said skirt portion and said mirror tube for preventing water intrusion into said mirror tube.
    Type: Grant
    Filed: November 12, 1996
    Date of Patent: August 17, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Tsutomu Onuma, Toshimi Matsumoto, Akira Onuma, Mitsuo Nakamura, Choichi Asano, Yasumasa Tamai, Hiroo Koide, Masayuki Kurihara, Takao Funamoto, Fuminori Ishikawa
  • Patent number: 5879132
    Abstract: An ultra high head pumpturbine power generating plant with a turbine having a runner rotating with water flow supplied through a high head conducting tube. A rotary electric machine rotates with rotation of the runner. The head is in the range of 400-600 m, and the runner is at least 5 meters in diameter. The said runner has characteristics of toughness at room temperature: at least 500 N/mm.sup.2, or tensile strength at room temperature: at least 650 N/mm.sup.2, elongation at least 16%, reduction of area at least 45%, 2 mm U-notch impact value at 0.degree. C. at least 100 J, and fracture toughness at least 6000 N/mm.sup.3/2.
    Type: Grant
    Filed: November 14, 1996
    Date of Patent: March 9, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Usami, Hiroshi Takayasu, Tsutomu Onuma, Makoto Kanda, Masao Kawakami, Fumio Sakamoto, Tsugio Fushimi, Tsugio Yoshikawa
  • Patent number: 5654992
    Abstract: A neutron-irradiated structural material having a defect in a nuclear reactor internals is repaired by covering the structural material to be repaired with a plate to cover over a portion thereof having the defect, and then welding the plate and the structural material by locally applying pressure on the surface of the plate and adding energy to the portion to which the pressure is applied thereby to generate thermal energy in the contact surfaces between the plate and the structural material.
    Type: Grant
    Filed: June 19, 1995
    Date of Patent: August 5, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Keiichi Uraki, Hisanori Okamura, Toshimi Matsumoto, Toshitaka Satsuta, Mitsuo Nakamura, Akira Onuma, Tsutomu Onuma, Takahiko Kato, Jun'ya Kaneda, Kunihiko Suzuki
  • Patent number: 5628449
    Abstract: Method of welding a carbon steel and a austenitic stainless steel involves using high density energy beam like a laser beam or electron beam. Welding using high density energy beam is effective to obtain a high precision welding. For the purpose of obtaining both high precision and no cracks, and no deformation, the method of the invention controls the structure of a weld portion to be a mixed structure of an austenitic structure and not greater than 20 wt % of a ferritic structure.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: May 13, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Tsutomu Onuma, Toshimi Matsumoto, Masami Yada, Koji Goto, Osamu Matsushima, Hideo Suzuki, Tatsuo Yonezawa, Masaki Murashita
  • Patent number: 5605778
    Abstract: A toner for developing electrostatic images is prepared from a binder resin, a colorant or magnetic material, and a wax component. The toner is provided with improved low-temperature fixability anti-electrostatic offset characteristic, anti-blocking characteristic and anti-offset characteristic by controlling the thermal characteristic of the wax component so as to provide a DSC (differential scanning colorimeter) curve on temperature increase, showing a minimum onset temperature of heat absorption of at least 50.degree. C. and at least two heat absorption peaks including a largest and a second largest peaks, different from each other in peak temperature by at least 15.degree. C., wherein low-temperature heat absorption peak P.sub.1 of the two peaks shows a half-value width of at most 20.degree. C. and a higher-temperature heat absorption peak P.sub.2 shows a half-value width of at most 20.degree. C., and wherein the peak P.sub.1 shows a higher half-width temperature and the peak P.sub.
    Type: Grant
    Filed: April 3, 1996
    Date of Patent: February 25, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tsutomu Onuma, Satoshi Matsunaga, Manabu Ohno, Minoru Shimojo
  • Patent number: 5601411
    Abstract: High toughness stainless steel type 13Cr5Ni containing C: 0.008-0.03% (by weight, all of the following elements), Si: max. 1%, Mn: max. 2%, Cr: 10.0-14.0%, Ni: 4.0-7.0%, and Mo: 0.2-2.0%, in which (Cr/Ni) ratio is in a range of 2.0-3.0 or (C/Mo) ratio is in a range of 0.015-0.1, as a structural material for fluid machinery, austenitic stainless steel containing C: 0.10-0.30% (by weight, all of the following elements), Si: max. 1%, Mn: max. 2%, Cr: 16.00-23.00%, Ni: 1.00-8.00%, and Co: 2.00-9.00%, and Ni+Co: 6.00-12.00% as a weld padding layer forming material, and fluid machinery using the same.
    Type: Grant
    Filed: June 19, 1995
    Date of Patent: February 11, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Usami, Hiroshi Takayasu, Tsutomu Onuma, Makoto Kanda, Masao Kawakami, Fumio Sakamoto, Tsugio Fushimi, Tsugio Yoshikawa
  • Patent number: 5384224
    Abstract: A toner for developing an electrostatic image is constituted by a binder resin and a hydrocarbon wax having a weight-average molecular weight of 800 to 3600. The toner is provided with good fixation characteristics including low-temperature fixability and anti-high temperature offsetting if the toner shows a storage modulus of at least 1.times.10.sup.3 dyn/cm.sup.2, a loss modulus in the range of 5.times.10.sup.2 -5.times.10.sup.4 dyn/cm.sup.2 and a ratio of loss modulus/storage modulus (loss tangent) of below 0.9 as measured under conditions of a frequency of 0.1 Hz and a temperature of 200.degree. C.; and the toner provides a DSC curve, as measured by a differential scanning calorimeter, showing an onset temperature of heat absorption of at most 105.degree. C. and a heat-absorption peak temperature in the range of 90.degree.-120.degree. C. on temperature increase, and a heat evolution peak temperature in the range of 62.degree.-75.degree. C. and a heat evolution peak intensity ratio of at least 2.times.10.
    Type: Grant
    Filed: March 4, 1993
    Date of Patent: January 24, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hirohide Tanikawa, Hiroaki Kawakami, Masatsugu Fujiwara, masashi Jinbo, Tsutomu Onuma