Patents by Inventor Masataka Kawahara

Masataka Kawahara 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: 20160124328
    Abstract: An electrophotographic photosensitive member wherein a charge generating layer of the electrophotographic photosensitive member includes a gallium phthalocyanine crystal in which an organic compound is contained, wherein the organic compound is at least one compound selected from the group consisting of dimethylsulfoxide, N,N-dimethylformamide, N-methylformamide, N-propylformamide, N-vinylformamide and N-methylpyrrolidone, the content of the organic compound is 0.1% by mass or more and 2.0% by mass or less based on a gallium phthalocyanine in the gallium phthalocyanine crystal, and a charge transporting layer of the electrophotographic photosensitive member includes a polycarbonate resin having structural units represented by formulae (1) and (2).
    Type: Application
    Filed: October 8, 2015
    Publication date: May 5, 2016
    Inventors: Masataka Kawahara, Masato Tanaka, Jumpei Kuno, Tsutomu Nishida, Kaname Watariguchi
  • Publication number: 20160124325
    Abstract: An electrophotographic photosensitive member includes a support and a photosensitive layer in this order. The photosensitive layer contains a chlorogallium phthalocyanine crystal obtained by mixing a hydroxygallium phthalocyanine crystal and an aqueous hydrochloric acid solution.
    Type: Application
    Filed: October 22, 2015
    Publication date: May 5, 2016
    Inventors: Tsutomu Nishida, Masato Tanaka, Masataka Kawahara, Jumpei Kuno, Kaname Watariguchi, Hidetoshi Hirano
  • Publication number: 20160124326
    Abstract: An electrophotographic photosensitive member includes a support and a photosensitive layer in this order. The photosensitive layer contains a chlorogallium phthalocyanine crystal. The chlorogallium phthalocyanine crystal has one or more peaks in each of a wavelength range of 646 nm or more and 668 nm or less and a wavelength range of 782 nm or more and 809 nm or less in an absorption spectrum. When a peak with a maximum absorbance among the peaks in the wavelength range of 646 nm or more and 668 nm or less is assumed to be a first peak and a peak with a maximum absorbance among the peaks in the wavelength range of 782 nm or more and 809 nm or less is assumed to be a second peak, an absorbance of the first peak is larger than an absorbance of the second peak.
    Type: Application
    Filed: October 22, 2015
    Publication date: May 5, 2016
    Inventors: Tsutomu Nishida, Masato Tanaka, Masataka Kawahara
  • Publication number: 20160124329
    Abstract: An electrophotographic photosensitive member includes a support and a photosensitive layer in this order. The photosensitive layer contains a chlorogallium phthalocyanine crystal represented by formula (1) in which at least one organic compound selected from N,N-dimethylformamide and dimethyl sulfoxide is contained. The content of the organic compound contained in the chlorogallium phthalocyanine crystal represented by the formula (1) is 0.10 mass % or more and 0.80 mass % or less based on a content of the chlorogallium phthalocyanine crystal represented by the formula (1).
    Type: Application
    Filed: October 22, 2015
    Publication date: May 5, 2016
    Inventors: Tsutomu Nishida, Masato Tanaka, Masataka Kawahara
  • Publication number: 20160091807
    Abstract: The present invention provides an electrophotographic photosensitive member comprising a support, and a photosensitive layer formed on the support, wherein the photosensitive layer contains a phthalocyanine crystal in which a 4-piperidone compound represented by the following formula (1) is contained.
    Type: Application
    Filed: May 22, 2014
    Publication date: March 31, 2016
    Applicant: CANNON KABUSHIKI KAISHA
    Inventors: Masato Tanaka, Tsutomu Nishida, Masataka Kawahara
  • Patent number: 9298115
    Abstract: In an electrophotographic photosensitive member including a charge-generating layer, the charge-generating layer has a matrix-domain structure; in the matrix-domain structure, the domain contains a charge-generating substance, and the matrix contains a binder resin and a fluoranthene compound.
    Type: Grant
    Filed: April 28, 2014
    Date of Patent: March 29, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventors: Junpei Kuno, Takeshi Murakami, Tsutomu Nishida, Masataka Kawahara, Kaname Watariguchi
  • Publication number: 20150370181
    Abstract: The present invention provides an electrophotographic photosensitive member which can output images with reduced image defects due to ghosting not only under a normal temperature and normal humidity environment but also even under a low temperature and low humidity environment as especially severe conditions, and a manufacturing method thereof; and a process cartridge and an electrophotographic apparatus each having the electrophotographic photosensitive member. Accordingly, the electrophotographic photosensitive member of the present invention having a support and a photosensitive layer on the support includes the photosensitive layer which contains a solid solution of hydroxygallium phthalocyanine and a compound represented by the following Formula (1) or Formula (1)?, the solid solution having peaks at Bragg angles 2? of 7.4°±0.3° and 28.3°±0.3° in CuK? characteristic X-ray diffraction.
    Type: Application
    Filed: June 16, 2015
    Publication date: December 24, 2015
    Inventors: Masato Tanaka, Tsutomu Nishida, Masataka Kawahara
  • Publication number: 20150362848
    Abstract: An electrophotographic photosensitive member can provide images in which black spots and fogging are suppressed and density unevenness due to coating unevenness of the charge generation layer is suppressed. The charge generation layer of the electrophotographic photosensitive member contains a gallium phthalocyanine crystal, a nitrogen-containing heterocyclic compound, and an amide compound represented by a formula (1), and a nitrogen atom in a heterocyclic ring of the nitrogen-containing heterocyclic compound has a substituent.
    Type: Application
    Filed: June 11, 2015
    Publication date: December 17, 2015
    Inventors: Kaname Watariguchi, Masato Tanaka, Masataka Kawahara, Jumpei Kuno, Tsutomu Nishida
  • Publication number: 20150362847
    Abstract: The present invention can provide an electrophotographic photosensitive member that is capable of suppressing potential variation as much as possible to allow a high-quality image to be output, as well as a process cartridge and an electrophotographic apparatus including the electrophotographic photosensitive member. Therefore, the electrophotographic photosensitive member of the present invention is an electrophotographic photosensitive member comprising: a support; a charge-generating layer; and a charge-transporting layer on the charge-generating layer, in which the charge-generating layer comprises a gallium phthalocyanine crystal in which a polar solvent is contained, and the polar solvent is at least one selected from dimethylsulfoxide, N,N-dimethylformamide, N-methylformamide, N-propylformamide, N-vinylformamide and N-methylpyrrolidone relative to gallium phthalocyanine, and the content of the polar solvent is 0.1% by mass or more and 2.
    Type: Application
    Filed: June 4, 2015
    Publication date: December 17, 2015
    Inventors: Masato Tanaka, Masataka Kawahara, Jumpei Kuno, Tsutomu Nishida, Kaname Watariguchi
  • Publication number: 20150362849
    Abstract: A photosensitive layer of an electrophotographic photosensitive member contains a particular chlorogallium phthalocyanine crystal in which an organic compound is contained. The organic compound has a Hansen solubility parameter ?total of 24.0 or more and 35.0 or less, a polar energy ?P of 13.5 or more and 21.0 or less, and a dispersion energy ?D of 15.0 or more and 19.5 or less.
    Type: Application
    Filed: June 10, 2015
    Publication date: December 17, 2015
    Inventors: Tsutomu Nishida, Masato Tanaka, Masataka Kawahara, Jumpei Kuno, Kaname Watariguchi
  • Publication number: 20150346617
    Abstract: The present invention provides: an electrophotographic photosensitive member which reduces image defects due to ghosting not only under a normal temperature and normal humidity environment but also even under a low temperature and low humidity environment; and a novel phthalocyanine crystal. The electrophotographic photosensitive member of the present invention includes a photosensitive layer which comprises a phthalocyanine crystal in which a dimethyl sulfoxide is contained. The content of the dimethyl sulfoxide is 0.1% by mass or more and 1.7% by mass or less based on the phthalocyanine crystal.
    Type: Application
    Filed: May 27, 2015
    Publication date: December 3, 2015
    Inventors: Masataka Kawahara, Tsutomu Nishida, Jumpei Kuno, Masato Tanaka, Kaname Watariguchi
  • Publication number: 20150346616
    Abstract: The present invention provides: an electrophotographic photosensitive member which reduces image defects due to ghosting not only under a normal temperature and normal humidity environment but also even under a low temperature and low humidity environment; and a novel phthalocyanine crystal. The electrophotographic photosensitive member of the present invention comprises a photosensitive layer which comprises a phthalocyanine crystal in which a N,N-dimethylformamide is contained. The content of the N,N-dimethylformamide is 0.1% by mass or more and 1.5% by mass or less based on the phthalocyanine crystal.
    Type: Application
    Filed: May 26, 2015
    Publication date: December 3, 2015
    Inventors: Masataka Kawahara, Masato Tanaka, Jumpei Kuno, Tsutomu Nishida, Kaname Watariguchi
  • Publication number: 20150316862
    Abstract: Provided is an electrophotographic photosensitive member, including a photosensitive layer that includes a phthalocyanine crystal in which a compound represented by the following formula (1) is contained: in the formula (1), X represents a vinyl group or a propyl group.
    Type: Application
    Filed: April 17, 2015
    Publication date: November 5, 2015
    Inventors: Junpei Kuno, Tsutomu Nishida, Masato Tanaka, Masataka Kawahara, Kaname Watariguchi
  • Publication number: 20150316864
    Abstract: An electrophotographic photosensitive member capable of outputting an image with suppressed positive ghosting, and a process cartridge and an electrophotographic apparatus each having the electrophotographic photosensitive member are provided. The electrophotographic photosensitive member has a photosensitive layer including a phthalocyanine crystal in which the compound represented by the formula (1) is contained, wherein the content of the compound represented by the formula (1) is 0.1% by mass or more and 1.7% by mass or less based on the phthalocyanine crystal.
    Type: Application
    Filed: April 17, 2015
    Publication date: November 5, 2015
    Inventors: Junpei Kuno, Tsutomu Nishida, Masato Tanaka, Masataka Kawahara, Kaname Watariguchi
  • Publication number: 20150316863
    Abstract: An electrophotographic photosensitive member is provided. The electrophotographic photosensitive member can output an image having few image defects due to a ghost phenomenon not only under a normal temperature and normal humidity environment but also even under a low temperature and low humidity environment, which is particularly a strict condition. A process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member are also provided. The electrophotographic photosensitive member has a support and a photosensitive layer formed on the support, wherein the photosensitive layer includes a gallium phthalocyanine crystal including a compound having a structure in which a 7-membered ring and a 5-membered ring are condensed to each other within the crystal.
    Type: Application
    Filed: April 6, 2015
    Publication date: November 5, 2015
    Inventors: Masato Tanaka, Tsutomu Nishida, Masataka Kawahara, Junpei Kuno
  • Publication number: 20150309426
    Abstract: A photosensitive layer includes a gallium phthalocyanine crystal and 0.2% by mass or more and 20% by mass or less of an arene compound based on the gallium phthalocyanine crystal, and the arene compound has a halogen atom or a halogen-substituted alkyl group, and a sulfonic acid group or a sulfonic acid salt group, as a substituent.
    Type: Application
    Filed: April 2, 2015
    Publication date: October 29, 2015
    Inventors: Tsutomu Nishida, Masato Tanaka, Masataka Kawahara
  • Publication number: 20150309427
    Abstract: An electrophotographic photosensitive member includes a support and a photosensitive layer on the support, and the photosensitive layer contains a hydroxygallium phthalocyanine crystal having peaks at Bragg angles 2?±0.2° of 6.9°, 7.7°, 16.4°, 24.4°, and 26.5° in CuK? X-ray diffraction.
    Type: Application
    Filed: April 22, 2015
    Publication date: October 29, 2015
    Inventors: Masataka Kawahara, Tsutomu Nishida, Junpei Kuno, Masato Tanaka, Kaname Watariguchi
  • Publication number: 20150309428
    Abstract: An electrophotographic photosensitive member includes a support and a photosensitive layer formed on the support. The photosensitive layer contains a phthalocyanine crystal in which a particular amide compound is contained.
    Type: Application
    Filed: April 22, 2015
    Publication date: October 29, 2015
    Inventors: Masataka Kawahara, Tsutomu Nishida, Junpei Kuno, Masato Tanaka, Kaname Watariguchi
  • Publication number: 20150234298
    Abstract: A solution of a gallium phthalocyanine contains a compound of formula (1) and a gallium phthalocyanine of formula (2), H2N—CH2—R1—CH2—NH2??(1) wherein R1 represents a single bond, or a substituted or unsubstituted alkylene group having 1 to 10 main-chain carbon atoms, a substituent of the substituted alkylene group is an alkyl group having 1 to 3 carbon atoms, an alkyl group having 1 to 3 carbon atoms and being substituted with an amino group, or a hydroxy group, one of the carbon atoms in the main chain of the alkylene group may be replaced with an oxygen atom, a sulfur atom, or a bivalent group represented by the formula —NR2—, and R2 represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 3 carbon atoms and being substituted with an amino group, and wherein X1 represents a chlorine atom or hydroxy group.
    Type: Application
    Filed: May 1, 2015
    Publication date: August 20, 2015
    Inventors: Tsutomu Nishida, Masato Tanaka, Masataka Kawahara
  • Patent number: 9104098
    Abstract: A charge-generating layer of an electrophotographic photosensitive member includes a phthalocyanine pigment and a specific tricyanoethylene compound. Alternatively, the charge-generating layer and/or an undercoat layer of the electrophotographic photosensitive member includes a specific tricyanoethylene compound, and the charge-generating layer includes the phthalocyanine pigment.
    Type: Grant
    Filed: August 29, 2013
    Date of Patent: August 11, 2015
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tsutomu Nishida, Junpei Kuno, Masataka Kawahara, Kaname Watariguchi, Masato Tanaka