Patents by Inventor Tomoko Sakimura
Tomoko Sakimura 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: 12032318Abstract: An electrophotographic image forming system forms an electrostatic latent image on at least a photoreceptor, develops an image using an electrostatic charge image developing toner, and removes the toner using a cleaning blade. A tip ridge of the cleaning blade is pressed against a surface of the photoreceptor. The system includes a photosensitive layer of the photoreceptor and a surface protecting layer that is provided on a surface of the photosensitive layer. The surface protecting layer includes a polymerizable monomer having at least two polymerizable groups in a molecule and a polymer of a hole transporting compound having a polymerizable group represented by General formula (1). The tip ridge of the cleaning blade has an edge angle that is obtuse and less than 120° and is pressed against the surface of the photoreceptor at an effective contact angle that is in a range of 8 to 20°.Type: GrantFiled: December 12, 2022Date of Patent: July 9, 2024Assignee: KONICA MINOLTA, INC.Inventors: Taiki Amemiya, Kazutoshi Kobayashi, Yukio Hosoya, Seijiro Takahashi, Tomoko Sakimura, Kazukuni Nishimura
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Publication number: 20230324818Abstract: Provided is an electrophotographic photoreceptor having at least a charge transport layer and a protective layer sequentially laminated on a conductive support, wherein the protective layer contains a cured product of a composition containing a charge transport compound having a chain polymerizable functional group; the charge transport layer and the protective layer are continuously laminated with intervening a mixed layer therebetween in which components of both layers of the charge transport layer and the protective layer are compatible; and the mixed layer has a thickness in the range of 0.1 to 1.0 ?m.Type: ApplicationFiled: March 31, 2023Publication date: October 12, 2023Inventors: Kazukuni NISHIMURA, Toshiyuki FUJITA, Hiroki TAKAO, Seijiro TAKAHASHI, Tomoko SAKIMURA
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Publication number: 20230185227Abstract: An electrophotographic image forming system forms an electrostatic latent image on at least a photoreceptor, develops an image using an electrostatic charge image developing toner, and removes the toner using a cleaning blade. A tip ridge of the cleaning blade is pressed against a surface of the photoreceptor. The system includes a photosensitive layer of the photoreceptor and a surface protecting layer that is provided on a surface of the photosensitive layer. The surface protecting layer includes a polymerizable monomer having at least two polymerizable groups in a molecule and a polymer of a hole transporting compound having a polymerizable group represented by General formula (1). The tip ridge of the cleaning blade has an edge angle that is obtuse and less than 120° and is pressed against the surface of the photoreceptor at an effective contact angle that is in a range of 8 to 20°.Type: ApplicationFiled: December 12, 2022Publication date: June 15, 2023Applicant: KONICA MINOLTA, INC.Inventors: Taiki AMEMIYA, Kazutoshi KOBAYASHI, Yukio HOSOYA, Seijiro TAKAHASHI, Tomoko SAKIMURA, Kazukuni NISHIMURA
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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: 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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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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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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Patent number: 10394144Abstract: An electrophotographic photosensitive body includes at least a photosensitive layer and a protective layer sequentially laminated on an electroconductive support, wherein the protective layer has a domain containing perfluoropolyether.Type: GrantFiled: February 8, 2018Date of Patent: August 27, 2019Assignee: KONICA MINOLTA, INC.Inventors: Tomoko Sakimura, Toyoko Shibata, Masanori Yumita
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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: 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: 10197929Abstract: The photoconductor includes a conductive support, a photosensitive layer, and a protective layer. The protective layer is a polymer of a radical-polymerizable composition containing a perfluoropolyether compound including a radical-polymerizable functional group, a radical-polymerizable monomer including a radical-polymerizable functional group, and an inorganic fine particle including a radical-polymerizable functional group. The radical-polymerizable functional group of the perfluoropolyether compound is different from the radical-polymerizable functional group of the radical-polymerizable monomer and identical to the radical-polymerizable functional group of the inorganic fine particle.Type: GrantFiled: December 6, 2017Date of Patent: February 5, 2019Assignee: KONICA MINOLTA, INC.Inventors: Masanori Yumita, Toyoko Shibata, Tomoko Sakimura