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).
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Patent number: 11237495Abstract: 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: GrantFiled: October 3, 2019Date of Patent: February 1, 2022Assignee: KONICA MINOLTA, INC.Inventors: Mayuko Matsusaki, Tomoko Sakimura, Hiroki Takao, Kengo Ikeda
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Patent number: 11169457Abstract: 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: GrantFiled: March 24, 2020Date of Patent: November 9, 2021Assignee: KONICA MINOLTA, INC.Inventors: Kengo Ikeda, Hiroki Takao, Tomoko Sakimura, Mayuko Matsusaki
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Patent number: 11169456Abstract: 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: GrantFiled: April 15, 2020Date of Patent: November 9, 2021Assignee: KONICA MINOLTA, INC.Inventors: Mayuko Matsusaki, Tomoko Sakimura, Hiroki Takao, Kengo Ikeda
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Patent number: 10948866Abstract: 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) areType: GrantFiled: October 2, 2019Date of Patent: March 16, 2021Assignee: KONICA MINOLTA, INC.Inventors: Kengo Ikeda, Hiroki Takao, Tomoko Sakimura, Mayuko Matsusaki
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Publication number: 20200363740Abstract: 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: ApplicationFiled: April 15, 2020Publication date: November 19, 2020Inventors: Mayuko MATSUSAKI, Tomoko SAKIMURA, Hiroki TAKAO, Kengo IKEDA
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Publication number: 20200319566Abstract: 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: ApplicationFiled: March 24, 2020Publication date: October 8, 2020Inventors: Kengo IKEDA, Hiroki TAKAO, Tomoko SAKIMURA, Mayuko MATSUSAKI
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Publication number: 20200257213Abstract: 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: ApplicationFiled: December 13, 2019Publication date: August 13, 2020Inventors: Tomoko Sakimura, Hiroki Takao, Mayuko Matsusaki, Kengo Ikeda
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Patent number: 10663875Abstract: 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: GrantFiled: July 22, 2019Date of Patent: May 26, 2020Assignee: KONICA MINOLTA, INC.Inventors: Tomoko Sakimura, Hiroki Takao, Mayuko Matsusaki, Kengo Ikeda
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Publication number: 20200142344Abstract: 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) areType: ApplicationFiled: October 2, 2019Publication date: May 7, 2020Inventors: Kengo IKEDA, Hiroki TAKAO, Tomoko SAKIMURA, Mayuko MATSUSAKI
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Publication number: 20200124997Abstract: 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: ApplicationFiled: October 3, 2019Publication date: April 23, 2020Inventors: Mayuko Matsusaki, Tomoko Sakimura, Hiroki Takao, Kengo Ikeda
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Publication number: 20200081358Abstract: 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: ApplicationFiled: August 16, 2019Publication date: March 12, 2020Inventors: Hiroki TAKAO, Tomoko SAKIMURA, Mayuko MATSUSAKI, Kengo IKEDA
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Publication number: 20200081360Abstract: 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: ApplicationFiled: July 22, 2019Publication date: March 12, 2020Inventors: Tomoko SAKIMURA, Hiroki TAKAO, Mayuko MATSUSAKI, Kengo IKEDA
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Patent number: 10585365Abstract: 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: GrantFiled: January 30, 2019Date of Patent: March 10, 2020Assignee: KONICA MINOLTA, INC.Inventors: Tomoko Sakimura, Hiroki Takao, Mayuko Matsusaki, Kengo Ikeda
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Publication number: 20190243261Abstract: 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: ApplicationFiled: January 30, 2019Publication date: August 8, 2019Inventors: Tomoko SAKIMURA, Hiroki TAKAO, Mayuko MATSUSAKI, Kengo IKEDA
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Publication number: 20190202194Abstract: 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: ApplicationFiled: December 6, 2018Publication date: July 4, 2019Inventors: Kengo IKEDA, Mayuko MATSUSAKI, Hirofumi HAYATA
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Publication number: 20190094725Abstract: 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: ApplicationFiled: August 7, 2018Publication date: March 28, 2019Inventors: Tomoko Sakimura, Hiroki Takao, Mayuko Matsusaki, Kengo Ikeda
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Patent number: 9772572Abstract: 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: GrantFiled: June 16, 2016Date of Patent: September 26, 2017Assignee: KONICA MINOLTA, INC.Inventors: Mayuko Matsusaki, Yasuko Uchino, Natsuko Fujisaki
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Publication number: 20170017176Abstract: 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: ApplicationFiled: June 16, 2016Publication date: January 19, 2017Inventors: Mayuko MATSUSAKI, Yasuko UCHINO, Natsuko FUJISAKI
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Patent number: 9201320Abstract: 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: GrantFiled: June 3, 2014Date of Patent: December 1, 2015Assignee: KONICA MINOLTA, INC.Inventors: Hiroshi Nakahara, Shinichi Hamaguchi, Tomoo Sakimura, Mayuko Matsusaki
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Patent number: 9063448Abstract: 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: GrantFiled: July 19, 2013Date of Patent: June 23, 2015Assignee: KONICA MINOLTA, INC.Inventors: Shinichi Hamaguchi, Tomoo Sakimura, Mayuko Matsusaki, Hiroshi Nakahara