Patents by Inventor Hiroaki Kawakami

Hiroaki Kawakami 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: 6077636
    Abstract: A toner is comprised of toner particles containing at least a binder resin and a colorant, and an external additive fine powder. The toner particles have a specific circularity distribution and a specific particle size distribution. The external additive fine powder has an inorganic fine powder having as primary particles a specific number-average particle length, and a non-spherical inorganic fine powder formed by coalescence of particles and having a specific shape factor and a specific number-average particle length.
    Type: Grant
    Filed: January 22, 1999
    Date of Patent: June 20, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yuji Moriki, Kenji Okado, Hiroaki Kawakami, Shinya Yachi, Michihisa Magome
  • Patent number: 5824442
    Abstract: A toner for developing electrostatic images has toner particles containing a binder resin and a colorant, and fine titanium oxide particles or fine alumina particles. The surfaces of the fine titanium oxide particles or fine alumina particles have been subjected to an organic treatment and have a methanol wettability half value of 55% or more.
    Type: Grant
    Filed: August 28, 1997
    Date of Patent: October 20, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hirohide Tanikawa, Hiroaki Kawakami, Masatsugu Fujiwara, Kazunori Kato
  • Patent number: 5814429
    Abstract: A heat fixable toner comprises a binder resin and a release agent. The binder resin comprises a polyester resin, and the release agent comprises a graft-modified polyolefin. A recording medium containing a toner image of said heat fixable toner is heat-fixed by contacting the recording medium with a heater element through a film interposed therebetween. After the heat-fixing step, the film is peeled from the fixed toner image while the film surface temperature is higher than the endothermic peak temperature of the toner.
    Type: Grant
    Filed: September 14, 1995
    Date of Patent: September 29, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroaki Kawakami, Yusuke Karami, Shinji Doi, Satoshi Matsunaga, Yasuhide Goseki, Takashige Kasuya, Masuo Yamazaki, Kiyoko Maeda
  • Patent number: 5743226
    Abstract: A valve lifter has a lifter body with a first surface arranged to feet on a pair of low lift cams on a camshaft, and a pair of hydraulic slides disposed in a bore of the lifter body. The slides have a stored position wherein they define therebetween and within the bore a chamber arranged to allow entry of a high lift cam on the camshaft disposed between the pair of low lift cams. The lifter body is formed with a window opening to the chamber to allow access of the high lift cam to the chamber. The slides have an operative position wherein they define a second surface opposite to the window arranged to rest on the high lift cam.
    Type: Grant
    Filed: July 18, 1997
    Date of Patent: April 28, 1998
    Assignee: Unisia Jecs Corporation
    Inventors: Tamotsu Tohdoh, Yasuo Fukuda, Hiroaki Kawakami
  • Patent number: 5707770
    Abstract: A toner for developing electrostatic images has toner particles containing a binder resin and a colorant, and fine titanium oxide particles or fine alumina particles. The surfaces of the fine titanium oxide particles or fine alumina particles have been subjected to an organic treatment and have a methanol wettability half value of 55% or more.
    Type: Grant
    Filed: November 8, 1995
    Date of Patent: January 13, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hirohide Tanikawa, Hiroaki Kawakami, Masatsugu Fujiwara, Kazunori Kato
  • Patent number: 5624104
    Abstract: It is an object to effectively and rapidly damp vibration of a vibrating object. A vibration isolating supporter includes a coil spring (3) interposed between an upper frame (1) and a lower frame (2) which are opposed to one another in a vertical direction, and is characterized in that a partition panel (4) is provided for the lower frame (2) to surround a periphery of the coil spring (3), a damping material (5) is accommodated in a portion surrounded by the partition panel (4), and a resisting member is disposed to be suspended in a hollow hole of the coil spring (3) of the upper frame (1) so as to be immersed in the damping material (5).
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: April 29, 1997
    Assignees: Nippon Steel Corporation, Showa Electric Wire and Cable Co., Ltd.
    Inventors: Koumei Hukuda, Kenji Takuma, Minori Kuriyama, Yoshimitsu Murahashi, Hiroaki Kawakami, Yuji Iida, Kazuki Inaba, Hiroyuki Tanaka, Katsumi Shimizu
  • Patent number: 5614344
    Abstract: A toner for developing electrostatic images contains toner particles containing at least a binder resin and a colorant as well as a fine powder comprised of base particles on which crystalline low resistance tin oxide films are formed. The crystalline low resistance tin oxide contains less than 100 ppm of antimony, arsenic and phosphorus, and has an oxygen deficiency structure. The toner is excellent in strength and can consistently give high quality images under any environmental conditions.
    Type: Grant
    Filed: June 13, 1995
    Date of Patent: March 25, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroaki Kawakami, Shinji Doi, Hirohide Tanikawa, Masatsugu Fujiwara, Kazunori Kato
  • Patent number: 5595371
    Abstract: It is an object to effectively and rapidly damp vibration of a vibrating object. A vibration isolating supporter includes a coil spring (3) interposed between an upper frame (1) and a lower frame (2) which are opposed to one another in a vertical direction, and is characterized in that a partition panel (4) is provided for the lower frame (2) to surround a periphery of the coil spring (3), a damping material (5) is accommodated in a portion surrounded by the partition panel (4), and a resisting member is disposed to be suspended in a hollow hole of the coil spring (3) of the upper frame (1) so as to be immersed in the damping material (5).
    Type: Grant
    Filed: November 23, 1994
    Date of Patent: January 21, 1997
    Assignees: Nippon Steel Corporation, Showa Electric Wire & Cable
    Inventors: Koumei Hukuda, Kenji Takuma, Minori Kuriyama, Yoshimitsu Murahashi, Hiroaki Kawakami, Yuji Iida, Kazuki Inaba, Hiroyuki Tanaka, Katsumi Shimizu
  • Patent number: 5543900
    Abstract: An image forming apparatus includes an image bearing member for bearing an image of toner and a charging member contactable to the image bearing member to charge the image bearing member. The charging member is adapted to receive a voltage and the toner has a melt index of not less than 0.5 g/10 min. In the apparatus,P/(V.times.L).ltoreq.50J/m.sup.2where v is a movement speed of the image bearing member when the image bearing member is charged by the charging member (m/sec), L is an effective charging length of the charging member, measured in a direction perpendicular to the movement direction of the image bearing member (m), and P is an amount of electric power consumed by the charging member (W).
    Type: Grant
    Filed: December 12, 1994
    Date of Patent: August 6, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Youichirou Maebashi, Haruo Fujii, Hiroshi Sasame, Hiroaki Kawakami, Tatsuya Kobayashi, Tetsuya Kobayashi, Naoki Enomoto, Akihiko Uchiyama, Yoshiro Saito
  • Patent number: 5478686
    Abstract: A heat fixable toner comprises a binder resin and a release agent. The binder resin comprises a polyester resin, and the release agent comprises a graft-modified polyolefin.
    Type: Grant
    Filed: March 25, 1993
    Date of Patent: December 26, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroaki Kawakami, Yusuke Karami, Shinji Doi, Satoshi Matsunaga, Yasuhide Goseki, Takashige Kasuya, Masuo Yamazaki, Kiyoko Maeda
  • Patent number: 5389487
    Abstract: An image forming process is disclosed which uses a non-magnetic one-component type developer comprising a finder resin and a releasing agent having specific properties. The developer has such advantages as being excellent in low-temperature fixability as well as anti-offset property.
    Type: Grant
    Filed: May 3, 1994
    Date of Patent: February 14, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroaki Kawakami, Shinji Doi, Keita Nozawa, Masatsugu Fujiwara, Masashi Jimbo
  • 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
  • Patent number: 5364722
    Abstract: A toner for developing electrostatic images is prepared from a binder resin and a hydrocarbon wax. The toner is provided with improved fixability and anti-offset characteristic by controlling the thermal characteristic of the hydrocarbon wax so as to provide a DSC (differential scanning calorimeter) curve, showing an onset temperature of heat absorption in the range of 50.degree.-110.degree. C. and at least one heat absorption peak P1 in the range of 70.degree.-130.degree. C. giving a peak temperature T.sub.P1 on temperature increase, and showing a maximum heat evolution peak temperature in the range of T.sub.P1 .+-.9.degree. C. on temperature decrease. Correspondingly, the toner provides a DSC curve showing a rising temperature of heat absorption of at least 80.degree. C., an onset temperature of heat absorption of at most 105.degree. C. and a heat absorption peak temperature in the range of 100.degree.-120.degree. C.
    Type: Grant
    Filed: September 10, 1992
    Date of Patent: November 15, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hirohide Tanikawa, Hiroaki Kawakami, Masatsugu Fujiwara, Masashi Jinbo, Tsutomu Onuma
  • Patent number: 5298354
    Abstract: A toner for developing an electrostatic image, comprises a binder resin and a colorant. Such binder resin contains a THF-insoluble component in an amount of less than 10 wt. % based on the binder resin, and, in the molecular weight distribution measured by GPC (gel permeation chromatography) of a THF-soluble component, has a weight average molecular weight/number average molecular weight (Mw/Mn) of .gtoreq.18, a molecular weight peak MA in the region of a molecular weight of from 3,000 to 20,000, a molecular weight peak MB in the region of a molecular weight of from 380,000 to 1,000,000, a molecular weight minimum Md in the region of a molecular weight of from 20,000 to 380,000, provided that MB/MA is in the range of from 30 to 150, and a molecular weight distribution curve area ratio SA:SB:Sd of 1:0.3 to 0.8:0.35 to 0.8.
    Type: Grant
    Filed: March 23, 1992
    Date of Patent: March 29, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventors: Satoshi Matsunaga, Takashige Kasuya, Hiroaki Kawakami, Kiyoko Tsuchiya, Yusuke Karami, Shinji Doi
  • Patent number: 5135833
    Abstract: A toner for developing an electrostatic image, comprises a binder resin and a colorant. Such binder resin contains a THF-insoluble matter in an amount of less than 10 wt. % based on the binder resin, and, in the molecular weight distribution measured by GPC (gel permeation chromatography) of a THF-soluble matter, has a weight average molecular weight/number average molecular weight (Mw/Mn) of .gtoreq.18, a molecular weight peak MA in the region of a molecular weight of from 3,000 to 20,000, a molecular weight peak MB in the region of a molecular weight of from 380,000 to 1,000,000, a molecular weight minimum Md in the region of a molecular weight of from 20,000 to 380,000, provided that MB/MA is in the range of from 30 to 150, and a molecular weight distribution curve area ratio SA:SB:Sd of 1:0.3 to 0.8:0.35 to 0.8.
    Type: Grant
    Filed: January 18, 1991
    Date of Patent: August 4, 1992
    Assignee: Canon Kabushiki Kaisha
    Inventors: Satoshi Matsunaga, Takashige Kasuya, Hiroaki Kawakami, Kiyoko Tsuchiya, Yusuke Karami, Shinji Doi
  • Patent number: 4957774
    Abstract: A method of heat-fixing a visible image of toner to a recording medium comprises applying a toner image onto the recording medium, whereinthe toner to form said toner image or the resin component of the toner has the properties such that the melt viscosity .eta.' measured by an overhead-type flow tester is from 10.sup.3 to 10.sup.6 poise at a temperature within the temperature range of from 120.degree. C. to 150.degree. C., and the absolute value of the inclination of a graph is not more than 0.50 ln (poise)/.degree.C. when the natural logarithms ln.eta. of the melt viscosities at 120.degree. C. and 150.degree. C. are plotted with respect to the temperatures; and heat-fixing the toner image retained on the recording medium to the recording medium by use of a heater element as stationarily supported and a pressure member that brings said recording medium into close contact with said heater element through a film interposed between them.
    Type: Grant
    Filed: December 13, 1989
    Date of Patent: September 18, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shinji Doi, Satoshi Yoshida, Satoshi Matsunaga, Hiroaki Kawakami, Takashige Kasuya, Yasuhide Goseki, Yusuke Karami
  • Patent number: 4816366
    Abstract: A toner for developing electrostatic latent images is produced by a process comprising the steps of: (a) stirring at least water, hardly water-soluble inorganic fine powder and a specific compound thereby to prepare an aqueous dispersion medium; (b) adding a polymerizable monomer composition comprising at least a polymerizable monomer and a polymerization initiator to the aqueous dispersion medium; (c) forming particles of the polymerizable monomer composition in the aquoeus dispersion medium; (d) subjecting the particles of the polymerizable monomer composition to suspension polymerization, thereby to produce toner particles; and (e) removing the hardly water-soluble inorganic fine powder attached to the surfaces of the toner particles by an aqueous alkaline or acidic solution.
    Type: Grant
    Filed: February 12, 1988
    Date of Patent: March 28, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshihiko Hyosu, Takeshi Ikeda, Hitoshi Kanda, Hiromi Mori, Hiroaki Kawakami, Kuniko Kobayashi