Patents by Inventor Yota Ito

Yota Ito 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: 11782353
    Abstract: A method for producing an electrophotographic photosensitive member including: forming a photosensitive layer; and forming a protective layer, wherein the step of forming the photosensitive layer forms a photosensitive layer having an amount of residual solvent of a first solvent in the photosensitive layer of 0.05% to 2.50% and an amount of residual solvent of a second solvent in the photosensitive layer of 0.50% to 2.50%, and the step of forming the protective layer includes step (A) of forming a cured film and step (B) of forming the protective layer having wrinkle shapes, wherein, in step (A), the irradiated coating film is heated at a heating temperature lower than a boiling point of the first solvent and in step (B), the cured film is heated at a heating temperature higher than a boiling point of the first solvent.
    Type: Grant
    Filed: April 13, 2021
    Date of Patent: October 10, 2023
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Nobuhiro Nakamura, Tomohito Ishida, Shuhei Iwasaki, Hiroyuki Watanabe, Tatsuya Yamaai, Yuka Ishiduka, Yota Ito, Takeshi Murakami
  • Patent number: 11392074
    Abstract: Provided is an electrophotographic photosensitive drum that achieves both of a reduction in torque of the electrophotographic photosensitive drum at the time of its cleaning and an improvement in image transferability. The electrophotographic photosensitive drum includes: a support; and a photosensitive layer arranged on the support, the electrophotographic photosensitive drum having arranged on an outer surface thereof at least two structure groups having different appearance periods, wherein when, out of the two structure groups, a group including structures having a smaller appearance period is defined as a first structure group, and a group including structures having a larger appearance period is defined as a second structure group, a height of the first structure group is lower than a height of the second structure group.
    Type: Grant
    Filed: April 13, 2021
    Date of Patent: July 19, 2022
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tomohito Ishida, Nobuhiro Nakamura, Shuhei Iwasaki, Hiroyuki Watanabe, Tatsuya Yamaai, Yuka Ishiduka, Yota Ito, Takeshi Murakami
  • Patent number: 11163241
    Abstract: An electrophotographic photosensitive member including: a support, an undercoat layer formed above the support, a charge generation layer formed on the undercoat layer, and a charge transport layer formed above the charge generation layer, wherein the undercoat layer contains a polyamide resin and a titanium oxide particle which is surface-treated with a compound represented by Formula (1): when a volume of the titanium oxide particles to a volume of the polyamide resin in the undercoat layer is a, and an average primary particle diameter of the titanium oxide particles is b [?m], the following Equation (A) is satisfied: Equation (A): 14.0?a/b?19.1; and the charge generation layer contains a charge generating material and a thermoplastic resin having a hydroxyl group and a hydroxyl number of 50 mgKOH/g or more.
    Type: Grant
    Filed: February 6, 2019
    Date of Patent: November 2, 2021
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yota Ito, Jumpei Kuno, Shoma Hinata
  • Publication number: 20210325794
    Abstract: There is provided an electrophotographic photosensitive member having drum shape, the electrophotographic photosensitive member including a support and a photosensitive layer, wherein an outer surface of the electrophotographic photosensitive member has wrinkles, and when an observation region having square form with one side of 100 ?m is placed at an arbitrary position on the outer surface, a line that passes through a central point of the observation region and is parallel to a circumferential direction of the electrophotographic photosensitive member is defined as a first reference line L1, and 3,599 reference lines obtained by rotating the first reference line L1 at every 0.1° around the central point are defined as L2 to L3,600, respectively, each of L1 to L3,600 intersects with convex portions of the wrinkles at a plurality of locations and has at least two different intersection angles selected from the plurality of locations.
    Type: Application
    Filed: April 14, 2021
    Publication date: October 21, 2021
    Inventors: Shuhei Iwasaki, Tomohito Ishida, Nobuhiro Nakamura, Hiroyuki Watanabe, Tatsuya Yamaai, Yuka Ishiduka, Yota Ito, Takeshi Murakami
  • Publication number: 20210325793
    Abstract: A method for producing an electrophotographic photosensitive member including: forming a photosensitive layer; and forming a protective layer, wherein the step of forming the photosensitive layer forms a photosensitive layer having an amount of residual solvent of a first solvent in the photosensitive layer of 0.05% to 2.50% and an amount of residual solvent of a second solvent in the photosensitive layer of 0.50% to 2.50%, and the step of forming the protective layer includes step (A) of forming a cured film and step (B) of forming the protective layer having wrinkle shapes, wherein, in step (A), the irradiated coating film is heated at a heating temperature lower than a boiling point of the first solvent and in step (B), the cured film is heated at a heating temperature higher than a boiling point of the first solvent.
    Type: Application
    Filed: April 13, 2021
    Publication date: October 21, 2021
    Inventors: Nobuhiro Nakamura, Tomohito Ishida, Shuhei Iwasaki, Hiroyuki Watanabe, Tatsuya Yamaai, Yuka lshiduka, Yota Ito, Takeshi Murakami
  • Publication number: 20210325814
    Abstract: Provided is an electrophotographic photosensitive drum that achieves both of a reduction in torque of the electrophotographic photosensitive drum at the time of its cleaning and an improvement in image transferability. The electrophotographic photosensitive drum includes: a support; and a photosensitive layer arranged on the support, the electrophotographic photosensitive drum having arranged on an outer surface thereof at least two structure groups having different appearance periods, wherein when, out of the two structure groups, a group including structures having a smaller appearance period is defined as a first structure group, and a group including structures having a larger appearance period is defined as a second structure group, a height of the first structure group is lower than a height of the second structure group.
    Type: Application
    Filed: April 13, 2021
    Publication date: October 21, 2021
    Inventors: Tomohito Ishida, Nobuhiro Nakamura, Shuhei Iwasaki, Hiroyuki Watanabe, Tatsuya Yamaai, Yuka lshiduka, Yota Ito, Takeshi Murakami
  • Patent number: 11150566
    Abstract: The present disclosure provides an electrophotographic photosensitive member that can simultaneously achieve the suppression of the occurrence of the black spot in a charged portion and the suppression of the deterioration in sensitivity of an exposed portion, even after stored in a high-temperature and high-humidity environment. An electrophotographic photosensitive member includes an electro-conductive support, an undercoat layer, a charge generation layer and a charge transport layer in this order, wherein an atomic concentration ratio R of the oxygen atom to the aluminum atom on the surface of the electro-conductive support, as measured by energy dispersive X-ray spectroscopy, satisfies the following Expression (1): 1.6?R??(1) and the undercoat layer includes a titanium oxide particle that is surface-treated with a particular silane compound.
    Type: Grant
    Filed: June 3, 2020
    Date of Patent: October 19, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Shuhei Iwasaki, Akira Sakakibara, Jumpei Kuno, Yota Ito, Kohei Makisumi
  • Publication number: 20210247546
    Abstract: The compound having a high refractive index characteristic and a high transmittance is a (meth)acrylate compound represented by the following general formula (1): in the general formula (1), X represents a phenylene group, Z1 to Z3 are selected from the group consisting of a phenyl group, a heteroaryl group, a phenylene group, a heteroarylene group, a phenylalkylene group having an alkylene group having 1 or more to 4 or less carbon atoms, and a heteroaralkylene group having an alkylene group having 1 or more to 4 or less carbon atoms, P1 to P3 are selected from the group consisting of an acryloyloxy group and a methacryloyloxy group, A is selected from the group consisting of an aryl group, a heteroaryl group, an arylene group, and a heteroarylene group, and “m” and “n” each represent 0 or 1, provided that when the “m” represents 0, the “n” represents 0.
    Type: Application
    Filed: April 22, 2021
    Publication date: August 12, 2021
    Inventors: Kei Tagami, Terunobu Saitoh, Akihito Saitoh, Yota Ito
  • Patent number: 11086241
    Abstract: An electrophotographic photoreceptor includes a support, an undercoat layer placed on the support, a charge generation layer placed on the undercoat layer, and a charge transport layer placed on the charge generation layer. The undercoat layer contains titanium oxide particles surface-treated with an organosilicon compound that is at least one member selected from the group consisting of compounds represented by formulas (1) to (8) and a polyamide resin. The charge generation layer contains hydroxygallium phthalocyanine.
    Type: Grant
    Filed: February 11, 2020
    Date of Patent: August 10, 2021
    Assignee: Canon Kabushiki Kaisha
    Inventors: Jumpei Kuno, Akira Sakakibara, Yota Ito, Shuhei Iwasaki, Kohei Makisumi
  • Publication number: 20210200108
    Abstract: An electrophotographic photosensitive member includes: a support, an undercoat layer, and a photosensitive layer in this order, wherein the undercoat layer comprises a polyamide resin, and titanium oxide particles having been subjected to a surface treatment with an organic silicon compound, when an average primary particle size of the titanium oxide particles having been subjected to the surface treatment with the organic silicon compound is defined as “b” [?m], and a mass ratio of a Si element to TiO2 in the titanium oxide particles having been subjected to the surface treatment with the organic silicon compound is defined as “c” [mass %], “b” and “c” satisfy a relationship expressed by the following Expression (B), 0.025?b×c?0.050, and the photosensitive layer is a monolayer type photosensitive layer comprising a charge generating substance, a hole transporting substance, and an electron transporting substance.
    Type: Application
    Filed: December 21, 2020
    Publication date: July 1, 2021
    Inventors: Yota Ito, Akira Sakakibara
  • Patent number: 10942462
    Abstract: The present disclosure provides an electrophotographic photosensitive member that reduces the accumulation of charge and the leakage which are caused by a repeated use in a long period of time. The electrophotographic photosensitive member has a support, an undercoat layer, a charge generation layer and a charge transport layer in this order, wherein the undercoat layer contains a polyamide resin, and a titanium oxide particle, wherein the titanium oxide particle has been surfacetreated with an organosilicon compound, wherein the undercoat layer satisfies 10???70, where ? represents a degree [%] of hydrophobicity of the titanium oxide particle which has been surfacetreated with the organosilicon compound; and the undercoat layer satisfies 0.015?(?×?)?0.040, where ? represents an average primary particle size [?m] of the titanium oxide particles, and ? represents a weight percentage [wt %] of an Si element of the organosilicon compound with respect to the titanium oxide particle.
    Type: Grant
    Filed: October 30, 2019
    Date of Patent: March 9, 2021
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yota Ito, Akira Sakakibara, Jumpei Kuno, Shuhei Iwasaki, Kohei Makisumi
  • Publication number: 20200393771
    Abstract: The present disclosure provides an electrophotographic photosensitive member that can simultaneously achieve the suppression of the occurrence of the black spot in a charged portion and the suppression of the deterioration in sensitivity of an exposed portion, even after stored in a high-temperature and high-humidity environment. An electrophotographic photosensitive member includes an electro-conductive support, an undercoat layer, a charge generation layer and a charge transport layer in this order, wherein an atomic concentration ratio R of the oxygen atom to the aluminum atom on the surface of the electro-conductive support, as measured by energy dispersive X-ray spectroscopy, satisfies the following Expression (1): 1.6?R??(1) and the undercoat layer includes a titanium oxide particle that is surface-treated with a particular silane compound.
    Type: Application
    Filed: June 3, 2020
    Publication date: December 17, 2020
    Inventors: Shuhei Iwasaki, Akira Sakakibara, Jumpei Kuno, Yota Ito, Kohei Makisumi
  • Patent number: 10831117
    Abstract: Provided is an electrophotographic photosensitive member that is improved in potential stability in long-term use under a high-temperature and high-humidity environment, and does not cause degradation in image quality, such as a low density. The electrophotographic photosensitive member includes: a support; an undercoat layer formed on the support; a charge-generating layer formed directly on the undercoat layer; and a charge-transporting layer formed on the charge-generating layer. The undercoat layer contains a polyamide resin, titanium oxide particles surface-treated with an organic silicon compound, and a compound represented by the following Formula (1), and has a content of the compound represented by the Formula (1) of 4 ppm or more and 80 ppm or less: in the Formula (1), R and R? each independently represent a methyl group or an ethyl group.
    Type: Grant
    Filed: November 18, 2019
    Date of Patent: November 10, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Akira Sakakibara, Yota Ito, Jumpei Kuno, Shuhei Iwasaki, Kohei Makisumi
  • Publication number: 20200264525
    Abstract: An electrophotographic photoreceptor includes a support, an undercoat layer placed on the support, a charge generation layer placed on the undercoat layer, and a charge transport layer placed on the charge generation layer. The undercoat layer contains titanium oxide particles surface-treated with an organosilicon compound that is at least one member selected from the group consisting of compounds represented by formulas (1) to (8) and a polyamide resin. The charge generation layer contains hydroxygallium phthalocyanine.
    Type: Application
    Filed: February 11, 2020
    Publication date: August 20, 2020
    Inventors: Jumpei Kuno, Akira Sakakibara, Yota Ito, Shuhei Iwasaki, Kohei Makisumi
  • Publication number: 20200174385
    Abstract: Provided is an electrophotographic photosensitive member that is improved in potential stability in long-term use under a high-temperature and high-humidity environment, and does not cause degradation in image quality, such as a low density. The electrophotographic photosensitive member includes: a support; an undercoat layer formed on the support; a charge-generating layer formed directly on the undercoat layer; and a charge-transporting layer formed on the charge-generating layer. The undercoat layer contains a polyamide resin, titanium oxide particles surface-treated with an organic silicon compound, and a compound represented by the following Formula (1), and has a content of the compound represented by the Formula (1) of 4 ppm or more and 80 ppm or less: in the Formula (1), R and R? each independently represent a methyl group or an ethyl group.
    Type: Application
    Filed: November 18, 2019
    Publication date: June 4, 2020
    Inventors: Akira Sakakibara, Yota Ito, Jumpei Kuno, Shuhei Iwasaki, Kohei Makisumi
  • Publication number: 20200159137
    Abstract: The present disclosure provides an electrophotographic photosensitive member that reduces the accumulation of charge and the leakage which are caused by a repeated use in a long period of time. The electrophotographic photosensitive member has a support, an undercoat layer, a charge generation layer and a charge transport layer in this order, wherein the undercoat layer contains a polyamide resin, and a titanium oxide particle, wherein the titanium oxide particle has been surfacetreated with an organosilicon compound, wherein the undercoat layer satisfies 10???70, where ? represents a degree [%] of hydrophobicity of the titanium oxide particle which has been surfacetreated with the organosilicon compound; and the undercoat layer satisfies 0.015?(?×?)?0.040, where ? represents an average primary particle size [?m] of the titanium oxide particles, and ? represents a weight percentage [wt %] of an Si element of the organosilicon compound with respect to the titanium oxide particle.
    Type: Application
    Filed: October 30, 2019
    Publication date: May 21, 2020
    Inventors: Yota Ito, Akira Sakakibara, Jumpei Kuno, Shuhei Iwasaki, Kohei Makisumi
  • Patent number: 10416581
    Abstract: An electrophotographic photosensitive member with suppressed potential variation even in the case that a protective layer including a cured material of a composition having a polymerizable functional group is used is provided. An electrophotographic photosensitive member including a support, a charge generation layer, a charge transport layer containing a charge transporting material, and a protective layer, in the order presented, wherein the charge transport layer contains a polycarbonate resin having a structure selected from a group A and a structure selected from a group B, and the protective layer includes a cured material of a composition containing a compound having at least a functional group selected from chain-polymerizable functional groups and sequential polymerizable functional groups.
    Type: Grant
    Filed: August 3, 2017
    Date of Patent: September 17, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yota Ito, Tsutomu Nishida, Shoma Hinata, Tatsuya Yamaai, Akira Sakakibara, Daisuke Miura
  • Publication number: 20190243260
    Abstract: An electrophotographic photosensitive member including: a support, an undercoat layer formed above the support, a charge generation layer formed on the undercoat layer, and a charge transport layer formed above the charge generation layer, wherein the undercoat layer contains a polyamide resin and a titanium oxide particle which is surface-treated with a compound represented by Formula (1): when a volume of the titanium oxide particles to a volume of the polyamide resin in the undercoat layer is a, and an average primary particle diameter of the titanium oxide particles is b [?m], the following Equation (A) is satisfied: Equation (A): 14.0?a/b?19.1; and the charge generation layer contains a charge generating material and a thermoplastic resin having a hydroxyl group and a hydroxyl number of 50 mgKOH/g or more.
    Type: Application
    Filed: February 6, 2019
    Publication date: August 8, 2019
    Inventors: Yota Ito, Jumpei Kuno, Shoma Hinata
  • Publication number: 20190121251
    Abstract: An electrophotographic photosensitive member includes a support, a charge generating layer containing a charge generation material, and a charge transporting layer containing a charge transport material in this order, the charge transporting layer serving as a surface layer. The charge transporting layer contains a polycarbonate resin having a particular structural unit.
    Type: Application
    Filed: December 21, 2018
    Publication date: April 25, 2019
    Inventors: Tsutomu Nishida, Akira Sakakibara, Daisuke Miura, Yota Ito, Shoma Hinata, Tatsuya Yamaai, Nobuo Kosaka
  • Patent number: 10209637
    Abstract: An electrophotographic photosensitive member includes a support, a charge generating layer containing a charge generation material, and a charge transporting layer containing a charge transport material in this order, the charge transporting layer serving as a surface layer. The charge transporting layer contains a polycarbonate resin having a particular structural unit.
    Type: Grant
    Filed: July 28, 2017
    Date of Patent: February 19, 2019
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tsutomu Nishida, Akira Sakakibara, Daisuke Miura, Yota Ito, Shoma Hinata, Tatsuya Yamaai, Nobuo Kosaka