Patents by Inventor Mayuko MATSUSAKI

Mayuko MATSUSAKI 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: 11237495
    Abstract: There is provided an electrophotographic photoreceptor obtained by sequentially laminating at least a photosensitive layer and an outermost layer on a conductive support, wherein the outermost layer contains a polymerized and cured product of a composition containing a polymerizable monomer and a filler, and the filler includes a conductive first filler surface-treated with a surface treatment agent having a silicone chain in a side chain, and a second filler having a relative dielectric constant which is lower than that of the first filler and 5 or less.
    Type: Grant
    Filed: October 3, 2019
    Date of Patent: February 1, 2022
    Assignee: KONICA MINOLTA, INC.
    Inventors: Mayuko Matsusaki, Tomoko Sakimura, Hiroki Takao, Kengo Ikeda
  • Patent number: 11169457
    Abstract: The present invention provides an electrophotographic image forming method using an electrophotographic photoconductor. The electrophotographic photoconductor has a protective layer. The surface of the protective layer has a projection structure. The average distance between neighboring projections among a plurality of projections R is set within the range of 100 to 250 nm. A toner including titanate compound particles attached to toner base particles is used.
    Type: Grant
    Filed: March 24, 2020
    Date of Patent: November 9, 2021
    Assignee: KONICA MINOLTA, INC.
    Inventors: Kengo Ikeda, Hiroki Takao, Tomoko Sakimura, Mayuko Matsusaki
  • Patent number: 11169456
    Abstract: An electrophotographic photoreceptor includes a cured outermost layer that includes a polymerized cured product including at least an inorganic filler and a phenol derivative. The inorganic filler is surface-modified with a surface modifier. The phenol derivative has a structure represented by Formula (1). In Formula (1), R1 and R3 each independently represent an alkyl group having three or more carbon atoms, R2 and R4 each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and L1 represents a linking group having at least 10 atoms with an atomic number of 12 or more.
    Type: Grant
    Filed: April 15, 2020
    Date of Patent: November 9, 2021
    Assignee: KONICA MINOLTA, INC.
    Inventors: Mayuko Matsusaki, Tomoko Sakimura, Hiroki Takao, Kengo Ikeda
  • Patent number: 10948866
    Abstract: An electrophotographic image forming apparatus includes: an electrophotographic photoreceptor; a charger that charges a surface of the electrophotographic photoreceptor; an exposer that exposes the charged electrophotographic photoreceptor; a developer that supplies a toner to the electrophotographic photoreceptor on which an electrostatic latent image is formed; a transferer that transfers a toner image formed on the electrophotographic photoreceptor; and a cleaner that removes a residual toner remaining on a surface of the electrophotographic photoreceptor, wherein the electrophotographic photoreceptor includes an outermost layer, a surface of the outermost layer has a projection structure due to a ridge of the inorganic filler, the toner contains toner base particles and metal oxide particles as an external additive externally added to the toner base particles, 70% or more of the toner base particles are covered with the metal oxide particles as the external additive, and following formulas (1) to (3) are
    Type: Grant
    Filed: October 2, 2019
    Date of Patent: March 16, 2021
    Assignee: KONICA MINOLTA, INC.
    Inventors: Kengo Ikeda, Hiroki Takao, Tomoko Sakimura, Mayuko Matsusaki
  • Publication number: 20200363740
    Abstract: An electrophotographic photoreceptor includes a cured outermost layer that includes a polymerized cured product including at least an inorganic filler and a phenol derivative. The inorganic filler is surface-modified with a surface modifier. The phenol derivative has a structure represented by Formula (1). In Formula (1), R1 and R3 each independently represent an alkyl group having three or more carbon atoms, R2 and R4 each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and L1 represents a linking group having at least 10 atoms with an atomic number of 12 or more.
    Type: Application
    Filed: April 15, 2020
    Publication date: November 19, 2020
    Inventors: Mayuko MATSUSAKI, Tomoko SAKIMURA, Hiroki TAKAO, Kengo IKEDA
  • Publication number: 20200319566
    Abstract: The present invention provides an electrophotographic image forming method using an electrophotographic photoconductor. The electrophotographic photoconductor has a protective layer. The surface of the protective layer has a projection structure. The average distance between neighboring projections among a plurality of projections R is set within the range of 100 to 250 nm. A toner including titanate compound particles attached to toner base particles is used.
    Type: Application
    Filed: March 24, 2020
    Publication date: October 8, 2020
    Inventors: Kengo IKEDA, Hiroki TAKAO, Tomoko SAKIMURA, Mayuko MATSUSAKI
  • Publication number: 20200257213
    Abstract: Provide is an electrophotographic image forming method containing: a charging step, an exposure step, a developing step, a transfer step and a cleaning step by using a photoreceptor, wherein the charging step has a charging device for charging the surface of the photoreceptor; the photoreceptor has a protective layer, the protective layer contains a polymerized cured product of a composition containing a polymerizable monomer and an inorganic filler, a surface of the protective layer has a plurality of convex portions due to protrusion of the inorganic filler; in the developing step, a toner in which alumina particles are externally added to toner mother particles is used, and an average distance R between adjacent convex portions among the plurality of convex portions is set in the range of 100 to 250 nm.
    Type: Application
    Filed: December 13, 2019
    Publication date: August 13, 2020
    Inventors: Tomoko Sakimura, Hiroki Takao, Mayuko Matsusaki, Kengo Ikeda
  • Patent number: 10663875
    Abstract: An electrophotographic photoreceptor includes an outermost layer formed of a polymerized cured product of a composition containing a polymerizable monomer and metal oxide particles surface-treated with a surface treatment agent having a silicone chain, wherein a ratio (r/r?) between a number average primary particle diameter (r) of metal oxide particles which are untreated base particles of the metal oxide particles surface-treated with the surface treatment agent having a silicone chain and a sphere equivalent particle diameter (r?) of the untreated base particles calculated from a specific surface area measured by a nitrogen adsorption method is 1.5 or more and 6.0 or less, and a surface treatment amount with the surface treatment agent having a silicone chain per surface area of the untreated base particles is 0.0005 g/m2 or more and 0.0015 g/m2 or less.
    Type: Grant
    Filed: July 22, 2019
    Date of Patent: May 26, 2020
    Assignee: KONICA MINOLTA, INC.
    Inventors: Tomoko Sakimura, Hiroki Takao, Mayuko Matsusaki, Kengo Ikeda
  • Publication number: 20200142344
    Abstract: An electrophotographic image forming apparatus includes: an electrophotographic photoreceptor; a charger that charges a surface of the electrophotographic photoreceptor; an exposer that exposes the charged electrophotographic photoreceptor; a developer that supplies a toner to the electrophotographic photoreceptor on which an electrostatic latent image is formed; a transferer that transfers a toner image formed on the electrophotographic photoreceptor; and a cleaner that removes a residual toner remaining on a surface of the electrophotographic photoreceptor, wherein the electrophotographic photoreceptor includes an outermost layer, a surface of the outermost layer has a projection structure due to a ridge of the inorganic filler, the toner contains toner base particles and metal oxide particles as an external additive externally added to the toner base particles, 70% or more of the toner base particles are covered with the metal oxide particles as the external additive, and following formulas (1) to (3) are
    Type: Application
    Filed: October 2, 2019
    Publication date: May 7, 2020
    Inventors: Kengo IKEDA, Hiroki TAKAO, Tomoko SAKIMURA, Mayuko MATSUSAKI
  • Publication number: 20200124997
    Abstract: There is provided an electrophotographic photoreceptor obtained by sequentially laminating at least a photosensitive layer and an outermost layer on a conductive support, wherein the outermost layer contains a polymerized and cured product of a composition containing a polymerizable monomer and a filler, and the filler includes a conductive first filler surface-treated with a surface treatment agent having a silicone chain in a side chain, and a second filler having a relative dielectric constant which is lower than that of the first filler and 5 or less.
    Type: Application
    Filed: October 3, 2019
    Publication date: April 23, 2020
    Inventors: Mayuko Matsusaki, Tomoko Sakimura, Hiroki Takao, Kengo Ikeda
  • Publication number: 20200081358
    Abstract: The electrophotographic photoreceptor includes a conductive support, a photosensitive layer disposed on the conductive support, and an outermost layer disposed on the photosensitive layer, in which the outermost layer includes a cured product of a composition containing a polymerizable monomer and two or more kinds of conductive metal oxide particles having different number average primary particle diameters from each other, and at least one of the two or more kinds of conductive metal oxide particles is surface-treated with a surface treating agent having a silicone chain as a side chain.
    Type: Application
    Filed: August 16, 2019
    Publication date: March 12, 2020
    Inventors: Hiroki TAKAO, Tomoko SAKIMURA, Mayuko MATSUSAKI, Kengo IKEDA
  • Publication number: 20200081360
    Abstract: An electrophotographic photoreceptor includes an outermost layer formed of a polymerized cured product of a composition containing a polymerizable monomer and metal oxide particles surface-treated with a surface treatment agent having a silicone chain, wherein a ratio (r/r?) between a number average primary particle diameter (r) of metal oxide particles which are untreated base particles of the metal oxide particles surface-treated with the surface treatment agent having a silicone chain and a sphere equivalent particle diameter (r?) of the untreated base particles calculated from a specific surface area measured by a nitrogen adsorption method is 1.5 or more and 6.0 or less, and a surface treatment amount with the surface treatment agent having a silicone chain per surface area of the untreated base particles is 0.0005 g/m2 or more and 0.0015 g/m2 or less.
    Type: Application
    Filed: July 22, 2019
    Publication date: March 12, 2020
    Inventors: Tomoko SAKIMURA, Hiroki TAKAO, Mayuko MATSUSAKI, Kengo IKEDA
  • Patent number: 10585365
    Abstract: An object of the present invention is to provide an image bearing member for electrophotography. The image bearing member has high mechanical properties which include abrasion resistance and scratch resistance, is excellent in toner releasability, and is capable of retaining these features. The present invention provides an image bearing member for electrophotography, which includes a surface layer, the surface layer being composed of a polymerization-cured product of a composition containing a polymerizable monomer and surface-treated metal oxide particles, and the surface-treated metal oxide particles are metal oxide particles surface-treated with a surface treating agent having a silicone side chain.
    Type: Grant
    Filed: January 30, 2019
    Date of Patent: March 10, 2020
    Assignee: KONICA MINOLTA, INC.
    Inventors: Tomoko Sakimura, Hiroki Takao, Mayuko Matsusaki, Kengo Ikeda
  • Publication number: 20190243261
    Abstract: An object of the present invention is to provide an image bearing member for electrophotography. The image bearing member has high mechanical properties which include abrasion resistance and scratch resistance, is excellent in toner releasability, and is capable of retaining these features. The present invention provides an image bearing member for electrophotography, which includes a surface layer, the surface layer being composed of a polymerization-cured product of a composition containing a polymerizable monomer and surface-treated metal oxide particles, and the surface-treated metal oxide particles are metal oxide particles surface-treated with a surface treating agent having a silicone side chain.
    Type: Application
    Filed: January 30, 2019
    Publication date: August 8, 2019
    Inventors: Tomoko SAKIMURA, Hiroki TAKAO, Mayuko MATSUSAKI, Kengo IKEDA
  • Publication number: 20190202194
    Abstract: An original plate for forming an ink film includes a surface layer including a stimulus-responsive compound which responds to an external stimulus to have reversibly changed affinity with water; and a resin.
    Type: Application
    Filed: December 6, 2018
    Publication date: July 4, 2019
    Inventors: Kengo IKEDA, Mayuko MATSUSAKI, Hirofumi HAYATA
  • Publication number: 20190094725
    Abstract: Provided is an electrophotographic photoreceptor containing a conductive support having thereon a photosensitive layer and a protective layer located on the photosensitive layer, wherein the protective layer contains a polymerized and cured product of a composition incorporating: a polymerizable monomer, a polymerizable perfluoropolyether compound, and metal oxide particles surface-modified with a surface modifying agent containing a fluorine atom.
    Type: Application
    Filed: August 7, 2018
    Publication date: March 28, 2019
    Inventors: Tomoko Sakimura, Hiroki Takao, Mayuko Matsusaki, Kengo Ikeda
  • Patent number: 9772572
    Abstract: Provided is an electrostatic latent image developing toner comprising toner matrix particles that comprise resin components comprising a vinyl resin as a main component and a crystalline resin, and a mold release agent. The electrostatic latent image developing toner includes a structural body in which a portion of the crystalline resin is in contact with the mold release agent, and a portion of the crystalline resin having a thread-like structure that is not in contact with the mold release agent, in cross-sections of the toner matrix particles.
    Type: Grant
    Filed: June 16, 2016
    Date of Patent: September 26, 2017
    Assignee: KONICA MINOLTA, INC.
    Inventors: Mayuko Matsusaki, Yasuko Uchino, Natsuko Fujisaki
  • Publication number: 20170017176
    Abstract: Provided is an electrostatic latent image developing toner comprising toner matrix particles that comprise resin components comprising a vinyl resin as a main component and a crystalline resin, and a mold release agent. The electrostatic latent image developing toner includes a structural body in which a portion of the crystalline resin is in contact with the mold release agent, and a portion of the crystalline resin having a thread-like structure that is not in contact with the mold release agent, in cross-sections of the toner matrix particles.
    Type: Application
    Filed: June 16, 2016
    Publication date: January 19, 2017
    Inventors: Mayuko MATSUSAKI, Yasuko UCHINO, Natsuko FUJISAKI
  • Patent number: 9201320
    Abstract: Disclosed is a production process of an organic photoreceptor which can suppress occurrence of uneven density and image defects. The production process of an organic photoreceptor, the organic photoreceptor including an intermediate layer and an organic photosensitive layer on the intermediate layer, includes: applying a coating liquid for forming the intermediate layer to a conductive support to form a coating film, the coating liquid being obtained by dissolving a binder resin in a solvent and dispersing first and second metal oxide fine particles therein; and drying the coating film. The Pe number of the first metal oxide fine particles is two or more times larger than that of the second metal oxide fine particles.
    Type: Grant
    Filed: June 3, 2014
    Date of Patent: December 1, 2015
    Assignee: KONICA MINOLTA, INC.
    Inventors: Hiroshi Nakahara, Shinichi Hamaguchi, Tomoo Sakimura, Mayuko Matsusaki
  • Patent number: 9063448
    Abstract: The present invention provides an electrophotographic photoconductor including an electrically conductive substrate, an intermediate layer, and a photosensitive layer that are formed on the electrically conductive support, the intermediate layer including first titanium oxide particles surface-treated with a first reactive organic silicon compound, second titanium oxide particles surface-treated with a second reactive organic silicon compound different from the first reactive organic silicon compound, and a binder resin. The first reactive organic silicon compound is methyl hydrogen polysiloxane. The second reactive organic silicon compound is a compound represented by the following general formula (1): R—Si—(X)3??(1) R represents a alkyl group having 1 to 10 carbon atoms substituted by at least one of acryloxy and methacryloxy groups or unsubstituted; and X represents an alkoxy group having 1 to 4 carbon atoms or a halogen atom.
    Type: Grant
    Filed: July 19, 2013
    Date of Patent: June 23, 2015
    Assignee: KONICA MINOLTA, INC.
    Inventors: Shinichi Hamaguchi, Tomoo Sakimura, Mayuko Matsusaki, Hiroshi Nakahara