Patents by Inventor Daisuke Tazawa

Daisuke Tazawa 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: 8831481
    Abstract: An electrophotographic apparatus does not have a unit for maintaining a uniform surface temperature of an electrophotographic photosensitive member through its surface. The electrophotographic photosensitive member has temperature dependent characteristics and is equally divided into two regions in a cylindrical shaft direction such that absolute values of the temperature dependence of the photosensitive-member characteristics in the two regions are not the same. The electrophotographic photosensitive member is arranged so that when, among the two regions, a region which has a smaller absolute value of the temperature dependence of the photosensitive-member characteristics is defined as a first region, and a region which has a larger absolute value of the temperature dependence of the photosensitive-member characteristics is defined as a second region.
    Type: Grant
    Filed: September 25, 2012
    Date of Patent: September 9, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Daisuke Tazawa, Tomohito Ozawa, Takanori Ueno
  • Patent number: 8758971
    Abstract: An image-forming method uses an electrophotographic photosensitive member having a surface layer formed of a hydrogenated amorphous silicon carbide in which a ratio of the number of carbon atoms to the sum of the number of silicon atoms and the number of the carbon atoms in the surface layer is 0.61 or more and 0.75 or less, and the sum of the atomic density of the silicon atoms and the atomic density of the carbon atoms in the surface layer is 6.60×1022 atoms/cm3 or more, and the peak wavelength of pre-exposure light is shorter than the peak wavelength of image exposure light.
    Type: Grant
    Filed: December 16, 2009
    Date of Patent: June 24, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuyoshi Akiyama, Shigenori Ueda, Daisuke Tazawa, Tomohito Ozawa
  • Patent number: 8563203
    Abstract: An electrophotographic photosensitive member is configured such that the average value Hx_ave of the content of hydrogen atoms in a central portion area of a photoconductive layer in a cylindrically axial direction thereof, the content Hx of the hydrogen atoms at an arbitrary point in the central portion area, the average value Hy_ave of the content of the hydrogen atoms in an end area of the photoconductive layer in the cylindrically axial direction thereof, and the content Hy of the hydrogen atoms at an arbitrary point in the end area satisfy 10?Hx_ave?30, Hx<Hy, |Hx_ave?Hx|?5, and 2?Hy_ave?Hx_ave?12.
    Type: Grant
    Filed: June 21, 2011
    Date of Patent: October 22, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yuu Nishimura, Hironori Owaki, Daisuke Tazawa
  • Patent number: 8465891
    Abstract: An electrophotographic photosensitive member includes a photoconductive layer, an intermediate layer, and a surface layer. When Si+C atom density in the surface layer is represented by DS×1022 atoms/cm3, the DS is 6.60 or more, and when the maximal value of H/(Si+H) in a distribution of hydrogen quantity in the photoconductive layer in a layer thickness direction is represented by HPmax, the average value of the H/(Si+H) in the second photoconductive region is represented by HP2, the DS and the HP2 satisfy the following expression (1) and the DS and the HPmax satisfy the following expression (2). HP2?0.07×DS?0.38??Expression (1) HPmax?0.04×DS+0.
    Type: Grant
    Filed: November 11, 2010
    Date of Patent: June 18, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tomohito Ozawa, Kazuyoshi Akiyama, Yuu Nishimura, Daisuke Tazawa
  • Patent number: 8445168
    Abstract: The present invention provides an electrophotographic photosensitive member including a photoconductive layer, an intermediate layer made of hydrogenated amorphous silicon carbide on the photoconductive layer, and a surface layer made of hydrogenated amorphous silicon carbide on the intermediate layer, wherein a ratio (C/(Si+C); C2) in the surface layer is 0.61 to 0.75, and a sum of atom density of silicon and carbon is 6.60×1022 atoms/cm3 or more, a ratio (C/(Si+C); C1) and a sum (D1) of atom density of silicon and carbon in the intermediate layer increase continuously from the photoconductive layer toward the surface layer without exceeding C2 and D2, and the intermediate layer has a continuous region in which C1 is 0.25 to C2 while D1 is 5.50×1022 to 6.45×1022 atoms/cm3, the region being 150 nm or larger in a layer thickness direction, and an electrophotographic apparatus equipped therewith.
    Type: Grant
    Filed: November 18, 2010
    Date of Patent: May 21, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuyoshi Akiyama, Tomohito Ozawa, Daisuke Tazawa, Yuu Nishimura
  • Patent number: 8440377
    Abstract: An electrophotographic photosensitive member includes a substrate, a photoconductive layer, an intermediate layer, and a surface layer sequentially formed. The intermediate layer contains silicon, carbon and hydrogen, and a distribution of a hydrogen ratio, which is a ratio of the number of hydrogen atoms to the number of silicon, carbon and hydrogen atoms, in the intermediate layer has a maximum region. A largest hydrogen atomic ratio in the intermediate layer is larger than a hydrogen atomic ratio in the surface layer, and the hydrogen atomic ratio in the surface layer is 0.30 to 0.45. A distribution of a carbon atomic ratio, which is a ratio of the number of carbon atoms to the number of silicon and carbon atoms, in the intermediate layer has a maximum and a minimum region. A carbon atomic ratio in the maximum region is 0.53 to 0.63, a carbon atomic ratio in the minimum region is 0.47 or more, and the maximum hydrogen region in the intermediate layer is partially superimposed on the minimum carbon region.
    Type: Grant
    Filed: November 18, 2010
    Date of Patent: May 14, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tomohito Ozawa, Motoya Yamada, Kazuyoshi Akiyama, Daisuke Tazawa
  • Publication number: 20110318678
    Abstract: An electrophotographic photosensitive member is configured such that the average value Hx_ave of the content of hydrogen atoms in a central portion area of a photoconductive layer in a cylindrically axial direction thereof, the content Hx of the hydrogen atoms at an arbitrary point in the central portion area, the average value Hy_ave of the content of the hydrogen atoms in an end area of the photoconductive layer in the cylindrically axial direction thereof, and the content Hy of the hydrogen atoms at an arbitrary point in the end area satisfy 10?Hx_ave?30, Hx<Hy, |Hx_ave?Hx|?5, and 2?Hy_ave?Hx_ave?12. An electrophotographic apparatus having the electrophotographic photosensitive member is provided.
    Type: Application
    Filed: June 21, 2011
    Publication date: December 29, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yuu Nishimura, Hironori Owaki, Daisuke Tazawa
  • Publication number: 20110129776
    Abstract: An image-forming method is provided which enable high-quality images to be formed over a long time period. In the image-forming method, an electrophotographic photosensitive member is used having a surface layer formed of a hydrogenated amorphous silicon carbide in which a ratio of the number of carbon atoms to the sum of the number of silicon atoms and the number of the carbon atoms in the surface layer is 0.61 or more and 0.75 or less, and the sum of the atomic density of the silicon atoms and the atomic density of the carbon atoms in the surface layer is 6.60×1022 atoms/cm3 or more, and the peak wavelength of pre-exposure light is shorter than the peak wavelength of image exposure light.
    Type: Application
    Filed: December 16, 2009
    Publication date: June 2, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kazuyoshi Akiyama, Shigenori Ueda, Daisuke Tazawa, Tomohito Ozawa
  • Publication number: 20110123915
    Abstract: The invention is an electrophotographic photosensitive member comprising a substrate, a photoconductive layer, an intermediate layer and a surface layer sequentially formed, wherein the intermediate contains silicon, carbon and hydrogen, a distribution of a hydrogen ratio which is a ratio of the number of hydrogen to the number of silicon, carbon and hydrogen in the intermediate has a maximum region, a largest hydrogen ratio in the intermediate is larger than a hydrogen ratio in the surface, the hydrogen ratio in the surface is 0.30 to 0.45, a distribution of a carbon ratio which is a ratio of the number of carbon to the number of silicon and carbon in the intermediate has a maximum and a minimum region, a carbon maximum region is 0.53 to 0.63, a carbon minimum region is 0.47 or more, and the maximum hydrogen region in the intermediate is partially superimposed on the minimum carbon region.
    Type: Application
    Filed: November 18, 2010
    Publication date: May 26, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tomohito Ozawa, Motoya Yamada, Kazuyoshi Akiyama, Daisuke Tazawa
  • Publication number: 20110123914
    Abstract: The present invention provides an electrophotographic photosensitive member including a photoconductive layer, an intermediate layer made of hydrogenated amorphous silicon carbide on the photoconductive layer, and a surface layer made of hydrogenated amorphous silicon carbide on the intermediate layer, wherein a ratio (C/(Si+C); C2) in the surface layer is 0.61 to 0.75, and a sum of atom density of silicon and carbon is 6.60×1022 atoms/cm3 or more, a ratio (C/(Si+C); C1) and a sum (D1) of atom density of silicon and carbon in the intermediate layer increase continuously from the photoconductive layer toward the surface layer without exceeding C2 and D2, and the intermediate layer has a continuous region in which C1 is 0.25 to C2 while D1 is 5.50×1022 to 6.45×1022 atoms/cm3, the region being 150 nm or larger in a layer thickness direction, and an electrophotographic apparatus equipped therewith.
    Type: Application
    Filed: November 18, 2010
    Publication date: May 26, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kazuyoshi Akiyama, Tomohito Ozawa, Daisuke Tazawa, Yuu Nishimura
  • Publication number: 20110117484
    Abstract: An electrophotographic photosensitive member includes a photoconductive layer, an intermediate layer, and a surface layer. When Si+C atom density in the surface layer is represented by DS×1022 atoms/cm3, the DS is 6.60 or more, and when the maximal value of H/(Si+H) in a distribution of hydrogen quantity in the photoconductive layer in a layer thickness direction is represented by HPmax, the average value of the H/(Si+H) in the second photoconductive region is represented by HP2, the DS and the HP2 satisfy the following expression (1) and the DS and the HPmax satisfy the following expression (2). HP2?0.07×DS?0.38??Expression (1) HPmax?0.04×DS+0.
    Type: Application
    Filed: November 11, 2010
    Publication date: May 19, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tomohito Ozawa, Kazuyoshi Akiyama, Yuu Nishimura, Daisuke Tazawa
  • Patent number: 7550180
    Abstract: In a plasma treatment method of and apparatus for treating the surface of a treatment target substrate by utilizing glow discharge produced by supplying high-frequency power into an inside-evacuated reactor through a high-frequency power supply means, a plurality of impedance regulation means for regulating impedances on the side of the reactor and on the side of the high-frequency power supply means are provided correspondingly to the impedances of a plurality of reactors, and the high-frequency power is supplied into the reactors via the impedance regulation means corresponding to the reactors. Plasma treatment can be made in a good efficiency and a low cost on a plurality of reactors having different impedances.
    Type: Grant
    Filed: March 26, 2008
    Date of Patent: June 23, 2009
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyasu Shirasuna, Tatsuyuki Aoike, Kazuyoshi Akiyama, Hitoshi Murayama, Takashi Otsuka, Daisuke Tazawa, Kazuto Hosoi, Yukihiro Abe
  • Publication number: 20080271676
    Abstract: In a plasma treatment method of and apparatus for treating the surface of a treatment target substrate by utilizing glow discharge produced by supplying high-frequency power into an inside-evacuated reactor through a high-frequency power supply means, a plurality of impedance regulation means for regulating impedances on the side of the reactor and on the side of the high-frequency power supply means are provided correspondingly to the impedances of a plurality of reactors, and the high-frequency power is supplied into the reactors via the impedance regulation means corresponding to the reactors. Plasma treatment can be made in a good efficiency and a low cost on a plurality of reactors having different impedances.
    Type: Application
    Filed: March 26, 2008
    Publication date: November 6, 2008
    Applicant: Canon Kabushiki Kaisha
    Inventors: Toshiyasu Shirasuna, Tatsuyuki Aoike, Kazuyoshi Akiyama, Hitoshi Murayama, Takashi Otsuka, Daisuke Tazawa, Kazuto Hosoi, Yukihiro Abe
  • Patent number: 7051671
    Abstract: A vacuum processing method including placing an article to be processed in a reaction container and simultaneously supplying at least two high-frequency powers having different frequencies to the same high-frequency electrode to generate plasma in the reaction container by the high-frequency powers introduced into the reaction container from the high-frequency electrode. The frequencies and power values of the at least two high-frequency powers supplied satisfy a required relationship.
    Type: Grant
    Filed: June 25, 2004
    Date of Patent: May 30, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Aoki, Toshiyasu Shirasuna, Hiroaki Niino, Kazuyoshi Akiyama, Hitoshi Murayama, Shinji Tsuchida, Daisuke Tazawa, Yukihiro Abe
  • Patent number: 6861373
    Abstract: A vacuum processing method that includes placing an article to be processed in a reaction container and simultaneously supplying at least two high-frequency powers having mutually different frequencies to at least one high-frequency electrode to generate plasma in the reaction container by the high-frequency powers introduced into the reaction container from the high-frequency electrode(s), thereby processing the article. The frequencies and power values of the at least two high-frequency powers supplied satisfy required relationships.
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: March 1, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Aoki, Toshiyasu Shirasuna, Hiroaki Niino, Kazuyoshi Akiyama, Hitoshi Murayama, Shinji Tsuchida, Daisuke Tazawa, Yukihiro Abe
  • Publication number: 20040232415
    Abstract: A vacuum processing method including placing an article to be processed in a reaction container and simultaneously supplying at least two high-frequency powers having different frequencies to the same high-frequency electrode to generate plasma in the reaction container by the high-frequency powers introduced into the reaction container from the high-frequency electrode. The frequencies and power values of the at least two high-frequency powers supplied satisfy a required relationship.
    Type: Application
    Filed: June 25, 2004
    Publication date: November 25, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Makoto Aoki, Toshiyasu Shirasuna, Hiroaki Niino, Kazuyoshi Akiyama, Hitoshi Murayama, Shinji Tsuchida, Daisuke Tazawa, Yukihiro Abe
  • Patent number: 6761128
    Abstract: In a plasma treatment method of and apparatus for treating the surface of a treatment target substrate by utilizing glow discharge produced by supplying high-frequency power into an inside-evacuated reactor through a high-frequency power supply means, a plurality of impedance regulation means for regulating impedances on the side of the reactor and on the side of the high-frequency power supply means are provided correspondingly to the impedances of a plurality of reactors, and the high-frequency power is supplied into the reactors via the impedance regulation means corresponding to the reactors. Plasma treatment can be made in a good efficiency and a low cost on a plurality of reactors having different impedances.
    Type: Grant
    Filed: July 6, 2001
    Date of Patent: July 13, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyasu Shirasuna, Tatsuyuki Aoike, Kazuyoshi Akiyama, Hitoshi Murayama, Takashi Otsuka, Daisuke Tazawa, Kazuto Hosoi, Yukihiro Abe
  • Publication number: 20040112864
    Abstract: In a plasma treatment method of and apparatus for treating the surface of a treatment target substrate by utilizing glow discharge produced by supplying high-frequency power into an inside-evacuated reactor through a high-frequency power supply means, a plurality of impedance regulation means for regulating impedances on the side of the reactor and on the side of the high-frequency power supply means are provided correspondingly to the impedances of a plurality of reactors, and the high-frequency power is supplied into the reactors via the impedance regulation means corresponding to the reactors. Plasma treatment can be made in a good efficiency and a low cost on a plurality of reactors having different impedances.
    Type: Application
    Filed: December 8, 2003
    Publication date: June 17, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Toshiyasu Shirasuna, Tatsuyuki Aoike, Kazuyoshi Akiyama, Hitoshi Murayama, Takashi Otsuka, Daisuke Tazawa, Kazuto Hosoi, Yukihiro Abe
  • Publication number: 20030049558
    Abstract: A vacuum processing method including placing an article to be processed in a reaction container and simultaneously supplying at least two high-frequency powers having different frequencies to the same high-frequency electrode to generate plasma in the reaction container by the high-frequency powers introduced into the reaction container from the high-frequency electrode. The frequencies and power values of the at least two high-frequency powers supplied satisfy the required relationship. Also, disclosed are a semiconductor device manufacturing method, a semiconductor device and a vacuum processing apparatus.
    Type: Application
    Filed: December 11, 2001
    Publication date: March 13, 2003
    Inventors: Makoto Aoki, Toshiyasu Shirasuna, Hiroaki Niino, Kazuyoshi Akiyama, Hitoshi Murayama, Shinji Tsuchida, Daisuke Tazawa, Yukihiro Abe
  • Patent number: 6486045
    Abstract: In order to make possible formation of a deposited film of a relatively large area at a treatment rate which could not accomplished by the plasma process of the prior art, and in order to make possible stable production of the deposited film without variation in film quality, in an apparatus and a method for forming a deposited film, a part of a reaction vessel is formed of a dielectric member, at least one high-frequency electrode is arranged so as to face at least one substrate with interposition of the dielectric member, an earth shield is arranged so as to cover the reaction vessel and the high-frequency electrode, plasma is generated between the high-frequency electrode and the substrate, and a deposited film is formed under the conditions in which the following equation: 0.
    Type: Grant
    Filed: May 10, 2001
    Date of Patent: November 26, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Otsuka, Tatsuyuki Aoike, Toshiyasu Shirasuna, Kazuyoshi Akiyama, Hitoshi Murayama, Daisuke Tazawa, Kazuto Hosoi