Patents by Inventor Yoshinobu Baba

Yoshinobu Baba 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: 9535006
    Abstract: Semiconductor nanoparticles of the present invention are particles each having a core-shell structure that includes a core and a shell surrounding the core. The core includes (AgIn)xZn2(1-x)S2 (0.4?x?0.95 holds). The shell includes ZnS or ZnO, and the semiconductor nanoparticles each have at least one hydrophilic functional group on a surface of the shell. As the hydrophilic functional group, for example, a carboxyl group or a sulfo group may be mentioned. Since having a low toxicity and a high emission quantum yield, the semiconductor nanoparticles as described above may be used for a fluorescent probe for biological labeling.
    Type: Grant
    Filed: October 17, 2013
    Date of Patent: January 3, 2017
    Assignee: NATIONAL UNIVERSITY CORPORATION NAGOYA UNIVERSITY
    Inventors: Hiroshi Yukawa, Hiroyasu Nishi, Tsukasa Torimoto, Yoshinobu Baba
  • Publication number: 20160202621
    Abstract: A toner is provided, where good cleanability is exhibited, abrasion variations of the photo conductor surface is reduced, and contamination of a charge member is reduced. The toner includes toner particles and organic-inorganic composite fine particles on the toner particle surfaces, wherein each of the organic-inorganic composite fine particles is a particle in which inorganic fine particles are exposed at the surfaces of vinyl based resin particles in such a way that convex portions derived from the inorganic fine particles are formed on the surfaces, the average circularity of the toner is 0.960 or more, and the absolute value Q of the amount of triboelectricity of the toner measured by a two-component method and the electrostatic adhesion F of the toner satisfy 0.003?F/Q2?0.040.
    Type: Application
    Filed: July 30, 2014
    Publication date: July 14, 2016
    Inventors: Yojiro Hotta, Shohei Tsuda, Taiji Katsura, Masaharu Miura, Yoshinobu Baba, Takayuki Itakura
  • Patent number: 9063443
    Abstract: The present invention provides a magnetic carrier that can stably impart charge to a toner on a long term basis and that exhibits an excellent toner separation property and thus exhibits an excellent developing performance. This magnetic carrier is a magnetic carrier in which a vinyl resin coats the surface of a resin-filled core in which a resin is filled in pores of a porous ferrite particle, wherein the resistivity, Mg content, and total content of Sr and Ca oxides of the porous ferrite particle exhibit prescribed values and the magnetic carrier has a total area—in the backscattered electron projection image obtained by observation using a scanning electron microscope at an acceleration voltage of 2.0 kV—for a region originating with the porous ferrite particle of from at least 0.2 area % to not more than 5.0 area % with reference to the projected area of the magnetic carrier.
    Type: Grant
    Filed: May 23, 2013
    Date of Patent: June 23, 2015
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Koh Ishigami, Kentaro Kamae, Nozomu Komatsu, Yoshinobu Baba
  • Patent number: 9058924
    Abstract: A magnetic carrier having a resin-containing ferrite particles each containing a porous ferrite core and a resin in pores of the porous ferrite core, wherein the porous ferrite core has a particular pore diameter corresponding to the maximum logarithmic differential pore volume in a pore diameter range from at least 0.10 ?m to not more than 3.00 ?m, the resistivity of the porous ferrite core is in a particular range, and the porous ferrite core contains an oxide of Mg in a particular amount and contains a particular amount of a oxide of at least one metal selected from the group consisting of Mn, Sr, and Ca.
    Type: Grant
    Filed: May 24, 2013
    Date of Patent: June 16, 2015
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Nozomu Komatsu, Kentaro Kamae, Koh Ishigami, Yoshinobu Baba
  • Patent number: 9034551
    Abstract: Provided is a two-component developer containing: a magnetic carrier obtained by coating a magnetic core with a resin; and toner, in which: the magnetic core contains at least a ferrite component and at least one kind of an oxide selected from the group consisting of SiO2 and Al2O3; the content of the oxide is 4.0 mass % or more and 40.0 mass % or less with respect to the magnetic core; the magnetic core has a specific resistance of 5.0×104 ?·cm or more and 5.0×108 ?·cm or less at the time of the application of 1,000 V/cm; the magnetic carrier has an intensity of magnetization in 79.6 kA/m of 40.0 Am2/kg or more and 65.0 Am2/kg or less, and a residual magnetization after the application of an external magnetic field of 79.6 kA/m of 3.0 Am2/kg or less; and the toner has a weight-average particle diameter (D4) of 3.0 ?m or more and 10.0 ?m or less and an average circularity of 0.940 or more and 0.990 or less.
    Type: Grant
    Filed: March 10, 2009
    Date of Patent: May 19, 2015
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tomoko Endo, Koh Ishigami, Naoki Okamoto, Yoshinobu Baba
  • Patent number: 8974994
    Abstract: Provided is a magnetic carrier satisfactory in terms of the suppression of leakage and solid carrier adhesion, charge-providing performance, and developability. The magnetic carrier is a magnetic carrier, including filled core particles of which pores of porous magnetic core particles are filled with a filling resin composition, and having a surface coated with a coating resin composition, in which the coating resin composition comprises a coating resin and a carbon black, an amount of the coating resin composition is 2.0 parts by mass or more and 5.0 parts by mass or less with respect to 100.0 parts by mass of the filled core particles; and a particle diameter of the carbon black in the coating resin composition Pv at a maximum frequency in a particle size distribution based on a volume of the carbon black is 1.0 ?m or more and 10.0 ?m or less.
    Type: Grant
    Filed: January 28, 2013
    Date of Patent: March 10, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kentaro Kamae, Koh Ishigami, Yoshinobu Baba
  • Patent number: 8945805
    Abstract: The present invention provides an image of high image quality by using a magnetic carrier coated with a novel coating resin composition. Further, the present invention stably provides a good image which is hardly influenced by environmental fluctuation and long-term use and has a superior stability of a charging amount when left to stand especially under high temperature and high humidity environments. The present invention also provides a magnetic carrier characterized in that a carrier core surface is coated with a copolymer containing at least, as copolymerization components, an acrylic monomer having a specific structure and an acrylic macromonomer having a specific structure.
    Type: Grant
    Filed: February 26, 2009
    Date of Patent: February 3, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshinobu Baba, Koh Ishigami, Naoki Okamoto, Tomoko Endo
  • Patent number: 8927188
    Abstract: A method of producing a magnetic carrier, having a coating process step in which a surface of a magnetic carrier core is coated with particles of a resin composition by a mechanical impact force. The coating process step has a first coating process step of mixing, dispersing, and fixing the particles on the surface of the core, and a second coating process step, which is performed after the first coating process step, of carrying out a film-forming coating process on the particles. In the first and second coating process steps, the peripheral velocity of the outermost end of stirring members, the coating process time, the product temperature at the end of the coating process, and the glass-transition temperature of the resin component satisfy specific relationships.
    Type: Grant
    Filed: July 26, 2013
    Date of Patent: January 6, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takeshi Naka, Masayuki Hama, Kentaro Kamae, Koh Ishigami, Yoshinobu Baba, Hiroaki Kawakami, Yojiro Hotta, Satoshi Mita
  • Publication number: 20150003875
    Abstract: An object of the present invention is to provide a two-component developer which can achieve a high-definition image with a smaller toner laid-on level than a conventional one, provides a color gamut comparable to that of printing, can respond to an increase in printing speed, and allows an image with a stable tinge to be formed even in long-term use. The object can be achieved by a two-component developer containing a cyan toner and a magnetic carrier, the two-component developer being characterized in that the cyan toner has the following characteristics: (i) when the concentration of the cyan toner in a solution of the cyan toner in chloroform is represented by Cc (mg/ml) and the absorbance of the solution at a wavelength of 712 nm is represented by A712, a relationship between Cc and A712 satisfies the relationship of 2.00<A712/Cc<8.15; (ii) the lightness L* and chroma C* of the cyan toner determined in a powder state satisfy the relationships of 25.0?L*?40.0 and 50.0?C*?60.
    Type: Application
    Filed: July 10, 2014
    Publication date: January 1, 2015
    Inventors: Koh Ishigami, Kazuo Terauchi, Noriyoshi Umeda, Tetsuya Ida, Naoki Okamoto, Yojiro Hotta, Yoshinobu Baba, Takayuki Itakura, Takeshi Yamamoto, Manami Haraguchi, Kenta Kubo
  • Patent number: 8921023
    Abstract: Provided is a magnetic carrier excellent in leakage, uniformity of a solid image having satisfactory charging stability and developing performance at low electric field. The magnetic carrier is a magnetic carrier comprising: a magnetic substance-dispersed resin carrier core, which contains a magnetic substance and a binding resin, and a coating resin on a surface thereof, wherein: the carrier core has resistivity at 1000 V/cm of 5.0×106-8.0×107 ?·cm, the magnetic substance has a number average particle diameter of 0.20-0.35 ?m; and comprises magnetic-substance particles having vertexes and a particle diameter of 0.53 ?m or more in an amount of 10.0-32.0 vol % based on a total amount of the magnetic substance; and wherein: the carrier core has Fe2O3 content of 98.00% by mass or more; and ZnO content of 0.06-0.50% by mass.
    Type: Grant
    Filed: August 7, 2013
    Date of Patent: December 30, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshinobu Baba, Koh Ishigami, Masayuki Hama, Kentaro Kamae, Hiroaki Kawakami
  • Patent number: 8920845
    Abstract: It is intended to provide a method whereby various kinds of microcapsules, which are usable in, for example, a gene vector, can be produced in a small amount. This production method comprises: feeding a fluid containing a substance to be encapsulated into at lease one (13) of material-feeding microchannels in a substrate in which these material-feeding microchannels (12, 13, 14) and a reaction microchannel (18) connected to these material-feeding microchannels are formed; feeding an envelop-forming fluid containing a material for forming envelopes into at least one of the other material-feeding microchannels (12, 14); and allowing the envelope-forming fluid and the fluid containing the encapsulated substance that converge in the reaction microchannel from each material-feeding microchannel to flow through the reaction microchannel while continuously maintaining the interface between the fluids formed at the confluence thereof.
    Type: Grant
    Filed: November 2, 2007
    Date of Patent: December 30, 2014
    Assignee: National University Corporation Nagoya University
    Inventors: Yoshinobu Baba, Manabu Tokeshi, Noritada Kaji, Hideyoshi Harashima, Kentaro Kogure, Yasuo Shinohara, Hiroshi Kuramoto
  • Publication number: 20140284528
    Abstract: Semiconductor nanoparticles of the present invention are particles each having a core-shell structure that includes a core and a shell surrounding the core. The core includes (AgIn)xZn2(1?x)S2 (0.4?x?0.95 holds). The shell includes ZnS or ZnO, and the semiconductor nanoparticles each have at least one hydrophilic functional group on a surface of the shell. As the hydrophilic functional group, for example, a carboxyl group or a sulfo group may be mentioned. Since having a low toxicity and a high emission quantum yield, the semiconductor nanoparticles as described above may be used for a fluorescent probe for biological labeling.
    Type: Application
    Filed: October 17, 2013
    Publication date: September 25, 2014
    Inventors: Hiroshi YUKAWA, Hiroyasu NISHI, Tsukasa TORIMOTO, Yoshinobu BABA
  • Publication number: 20140220487
    Abstract: A magnetic carrier is provided which can suppress a decrease in glossiness even in a long term use for POD which requires high glossiness. A magnetic carrier includes a filled core particle in which a silicone resin is filled in pores of a porous magnetic core particle and a vinyl resin coating a surface of the filled core particle. In a pore distribution of the porous magnetic core particle measured by a mercury intrusion method, a cumulative pore volume in a pore diameter range of 0.1 to 3.0 ?m is 35.0 to 95.0 mm3/g, and in a pore distribution of the filled core particle measured by a mercury intrusion method, a cumulative pore volume in a pore diameter range of 0.1 to 3.0 ?m is 3.0 to 15.0 mm3/g. The magnetic carrier includes 1.2 to 3.0 parts by mass of the vinyl resin to 100.0 parts by mass of the filled core particle.
    Type: Application
    Filed: June 21, 2012
    Publication date: August 7, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kentaro Kamae, Nozomu Komatsu, Koh Ishigami, Yoshinobu Baba
  • Publication number: 20140134535
    Abstract: Provided is a magnetic carrier satisfying leakage, white spots, charging property and high developing performance in a low electric field and having excellent durability. The magnetic carrier is a magnetic carrier comprising a magnetic substance-dispersed resin carrier core containing a magnetic substance and a binder resin, and a coating resin on a surface thereof, wherein the magnetic substance comprises a magnetic substance A having a shape without vertexes and a magnetic substance B having a shape with vertexes, the magnetic substance B has a number average particle diameter of 0.40-2.00 ?m, and in a reflection electron image of a section of the magnetic substance-dispersed resin carrier core taken by a scanning electron microscope, an area proportion of the magnetic substance B is larger than an area proportion of the magnetic substance A within a region from the surface of the magnetic substance-dispersed resin carrier core to a depth of 1.0 ?m.
    Type: Application
    Filed: January 17, 2014
    Publication date: May 15, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yoshinobu Baba, Koh Ishigami, Masayuki Hama, Kentaro Kamae, Hiroaki Kawakami
  • Patent number: 8722303
    Abstract: An image forming method using a two component developing system is provided in which a print speed is not less than 300 mm/s, a peak-to-peak voltage of an AC component in a developing bias is not more than 1.3 kV, a sufficient image density can be ensured, and a recorded image having a small amount of magnetic carrier remaining on the image and having high image quality can be obtained. A magnetic carrier that forms a two component developer contains a magnetic core and a resin. The magnetic core is a ferrite containing Sr and Ca inside thereof at the same time, having a small crystal grain diameter, a high density crystal-grain boundary structure, and an extremely large capacitance of the grain boundary. Use of the ferrite can provide the above method.
    Type: Grant
    Filed: August 24, 2012
    Date of Patent: May 13, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Juun Horie, Takeshi Yamamoto, Yoshinobu Baba, Koh Ishigami
  • Publication number: 20140045115
    Abstract: Provided is a magnetic carrier excellent in leakage, uniformity of a solid image having satisfactory charging stability and developing performance at low electric field. The magnetic carrier is a magnetic carrier comprising: a magnetic substance-dispersed resin carrier core, which contains a magnetic substance and a binding resin, and a coating resin on a surface thereof, wherein: the carrier core has resistivity at 1000 V/cm of 5.0×106-8.0×107 ?·cm, the magnetic substance has a number average particle diameter of 0.20-0.35 ?m; and comprises magnetic-substance particles having vertexes and a particle diameter of 0.53 ?m or more in an amount of 10.0-32.0 vol % based on a total amount of the magnetic substance; and wherein: the carrier core has Fe2O3 content of 98.00% by mass or more; and ZnO content of 0.06-0.50% by mass.
    Type: Application
    Filed: August 7, 2013
    Publication date: February 13, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yoshinobu Baba, Koh Ishigami, Masayuki Hama, Kentaro Kamae, Hiroaki Kawakami
  • Publication number: 20140038098
    Abstract: A method of producing a magnetic carrier, having a coating process step in which a surface of a magnetic carrier core is coated with particles of a resin composition by a mechanical impact force. The coating process step has a first coating process step of mixing, dispersing, and fixing the particles on the surface of the core, and a second coating process step, which is performed after the first coating process step, of carrying out a film-forming coating process on the particles. In the first and second coating process steps, the peripheral velocity of the outermost end of stirring members, the coating process time, the product temperature at the end of the coating process, and the glass-transition temperature of the resin component satisfy specific relationships.
    Type: Application
    Filed: July 26, 2013
    Publication date: February 6, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Takeshi Naka, Masayuki Hama, Kentaro Kamae, Koh Ishigami, Yoshinobu Baba, Hiroaki Kawakami, Yojiro Hotta, Satoshi Mita
  • Publication number: 20140030650
    Abstract: A magnetic carrier having a resin-containing ferrite particles each containing a porous ferrite core and a resin in pores of the porous ferrite core, wherein the porous ferrite core has a particular pore diameter corresponding to the maximum logarithmic differential pore volume in a pore diameter range from at least 0.10 ?m to not more than 3.00 ?m, the resistivity of the porous ferrite core is in a particular range, and the porous ferrite core contains an oxide of Mg in a particular amount and contains a particular amount of a oxide of at least one metal selected from the group consisting of Mn, Sr, and Ca.
    Type: Application
    Filed: May 24, 2013
    Publication date: January 30, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Nozomu Komatsu, Kentaro Kamae, Koh Ishigami, Yoshinobu Baba
  • Publication number: 20130316282
    Abstract: The present invention provides a magnetic carrier that can stably impart charge to a toner on a long term basis and that exhibits an excellent toner separation property and thus exhibits an excellent developing performance. This magnetic carrier is a magnetic carrier in which a vinyl resin coats the surface of a resin-filled core in which a resin is filled in pores of a porous ferrite particle, wherein the resistivity, Mg content, and total content of Sr and Ca oxides of the porous ferrite particle exhibit prescribed values and the magnetic carrier has a total area—in the backscattered electron projection image obtained by observation using a scanning electron microscope at an acceleration voltage of 2.0 kV—for a region originating with the porous ferrite particle of from at least 0.2 area % to not more than 5.0 area % with reference to the projected area of the magnetic carrier.
    Type: Application
    Filed: May 23, 2013
    Publication date: November 28, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Koh Ishigami, Kentaro Kamae, Nozomu Komatsu, Yoshinobu Baba
  • Publication number: 20130244159
    Abstract: Provided is a two-component developer having excellent developing performance and little change in image concentration, and achieving long-term suppression of image defects such as transfer failure and fogging. Provided is a two-component developer containing a magnetic carrier and a toner, wherein the magnetic carrier has magnetic carrier particles comprising a silicone resin B coated on the surfaces of filled core particles in which pores of porous magnetic core particles are filled with a silicone resin A, the silicone resin A is a silicone resin cured in the presence of a non-metal catalyst or without a catalyst, while the silicone resin B is a silicone resin cured in the presence of a metal catalyst having titanium or zirconium, and the toner contains a binder resin, a release agent and a colorant, and has an average circularity of 0.940 or more.
    Type: Application
    Filed: November 24, 2011
    Publication date: September 19, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Koh Ishigami, Nozomu Komatsu, Kentaro Kamae, Yoshinobu Baba