Patents by Inventor Yuko Iwashita
Yuko Iwashita 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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Publication number: 20220100111Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single layer and contains a charge generating material, an electron transport material, a binder resin, and a hole transport material. The electron transport material includes a compound represented by general formula (1): In general formula (1), R1 and R2 each represent, independently of one another, a hydrogen atom, an alkyl group, a heterocyclic group, an alkoxy group, an aralkyl group, an allyl group, or an aryl group optionally substituted with at least 1 and no more than 5 substituents selected from the group consisting of a halogen atom, an alkyl group, and alkoxy group.Type: ApplicationFiled: September 22, 2021Publication date: March 31, 2022Applicant: KYOCERA Document Solutions Inc.Inventors: Yuko IWASHITA, Kazunari HAMASAKI, Jun AZUMA
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Publication number: 20220100110Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single layer, and contains a charge generating material, an electron transport material, a binder resin, and a hole transport material. The electron transport material includes a compound represented by general formula (1). The binder resin includes a polycarbonate resin having an end group and a main chain represented by general formula (10).Type: ApplicationFiled: September 22, 2021Publication date: March 31, 2022Applicant: KYOCERA Document Solutions Inc.Inventors: Yuko IWASHITA, Kazunari HAMASAKI
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Patent number: 11003101Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The hole transport material includes a compound represented by chemical formula (1-1) or (1-2). The photosensitive layer further contains an n-type pigment. The n-type pigment is preferably an azo pigment or a perylene pigment.Type: GrantFiled: January 10, 2020Date of Patent: May 11, 2021Assignee: KYOCERA Document Solutions Inc.Inventors: Yuko Iwashita, Kazunari Hamasaki
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Patent number: 10802411Abstract: An electrophotographic photosensitive member includes a photosensitive layer of a single layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. An optical response time is 0.05 milliseconds or longer and 0.85 milliseconds or shorter. The optical response time is a time from irradiation of a surface of the photosensitive layer charged to +800 V with pulse light having a wavelength of 780 nm to decay of a surface potential of the photosensitive layer from +800 V to +400 V. The pulse light has an intensity that allows the surface potential of the photosensitive layer to decay to +200 V from +800 V after 400 milliseconds elapse from the irradiation of the surface of the photosensitive layer charged to +800 V with the pulse light. The photosensitive layer has a Martens hardness at 50° C. of at least 160 N/mm2.Type: GrantFiled: March 16, 2018Date of Patent: October 13, 2020Assignee: KYOCERA Document Solutions Inc.Inventors: Yuko Iwashita, Kazunari Hamasaki, Kazutaka Sugimoto
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Publication number: 20200233323Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The hole transport material includes a compound represented by chemical formula (1-1) or (1-2). The photosensitive layer further contains an n-type pigment. The n-type pigment is preferably an azo pigment or a perylene pigment.Type: ApplicationFiled: January 10, 2020Publication date: July 23, 2020Applicant: KYOCERA Document Solutions Inc.Inventors: Yuko IWASHITA, Kazunari HAMASAKI
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Patent number: 10635008Abstract: An electrophotographic photosensitive member includes a conductive substrate and a single-layer photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, an additive, and a binder resin. An optical response time is in a range from 0.05 milliseconds to 0.85 milliseconds. The optical response time is a time from irradiation of a surface of the photosensitive layer charged to +800 V with pulse light having a wavelength of 780 nm to surface potential decay of the photosensitive layer from +800 V to +400 V. An optical intensity of the pulse light is set so that the surface potential of the photosensitive layer becomes +200 V from +800 V after 400 milliseconds from pulse light irradiation of the surface of the photosensitive layer charged to the +800 V. The additive includes either of both an ultraviolet absorbing agent and an antioxidant.Type: GrantFiled: January 28, 2019Date of Patent: April 28, 2020Assignee: KYOCERA Document Solutions Inc.Inventors: Yuko Iwashita, Kazunari Hamasaki, Kazutaka Sugimoto
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Publication number: 20200057396Abstract: An electrophotographic photosensitive member includes a photosensitive layer of a single layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. An optical response time is 0.05 milliseconds or longer and 0.85 milliseconds or shorter. The optical response time is a time from irradiation of a surface of the photosensitive layer charged to +800 V with pulse light having a wavelength of 780 nm to decay of a surface potential of the photosensitive layer from +800 V to +400 V. The pulse light has an intensity that allows the surface potential of the photosensitive layer to decay to +200 V from +800 V after 400 milliseconds elapse from the irradiation of the surface of the photosensitive layer charged to +800 V with the pulse light. The photosensitive layer has a Martens hardness at 50° C. of at least 160 N/mm2.Type: ApplicationFiled: March 16, 2018Publication date: February 20, 2020Applicant: KYOCERA Document Solutions Inc.Inventors: Yuko IWASHITA, Kazunari HAMASAKI, Kazutaka SUGIMOTO
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Patent number: 10539889Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer of a single layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. An optical response time is at least 0.05 milliseconds and no greater than 0.85 milliseconds. The binder resin includes a polycarbonate resin including a repeating unit represented by general formula (1) shown below and a repeating unit represented by general formula (2) shown below.Type: GrantFiled: January 29, 2019Date of Patent: January 21, 2020Assignee: KYOCERA Document Solutions Inc.Inventors: Yuko Iwashita, Kazunari Hamasaki, Kazutaka Sugimoto
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Publication number: 20190235399Abstract: An electrophotographic photosensitive member includes a conductive substrate and a single-layer photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, an additive, and a binder resin. An optical response time is in a range from 0.05 milliseconds to 0.85 milliseconds. The optical response time is a time from irradiation of a surface of the photosensitive layer charged to +800 V with pulse light having a wavelength of 780 nm to surface potential decay of the photosensitive layer from +800 V to +400 V. An optical intensity of the pulse light is set so that the surface potential of the photosensitive layer becomes +200 V from +800 V after 400 milliseconds from pulse light irradiation of the surface of the photosensitive layer charged to the +800 V. The additive includes either of both an ultraviolet absorbing agent and an antioxidant.Type: ApplicationFiled: January 28, 2019Publication date: August 1, 2019Applicant: KYOCERA Document Solutions Inc.Inventors: Yuko IWASHITA, Kazunari HAMASAKI, Kazutaka SUGIMOTO
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Publication number: 20190235400Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer of a single layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. An optical response time is at least 0.05 milliseconds and no greater than 0.85 milliseconds. The binder resin includes a polycarbonate resin including a repeating unit represented by general formula (1) shown below and a repeating unit represented by general formula (2) shown below.Type: ApplicationFiled: January 29, 2019Publication date: August 1, 2019Applicant: KYOCERA Document Solutions Inc.Inventors: Yuko IWASHITA, Kazunari HAMASAKI, Kazutaka SUGIMOTO
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Patent number: 9760029Abstract: An electrophotographic photosensitive member includes a single-layer type photosensitive layer including phthalocyanine or a derivative thereof and an electron transport material. The electron transport material includes at least one first compound represented by formula (1) or (2) shown below and at least one second compound represented by formula (3), (4), or (5) shown below. A total amount of the at least one first compound and the at least one second compound is no less than 60 parts by mass and no greater than 120 parts by mass relative to 100 parts by mass of the binder resin. An amount of the at least one first compound is no less than 35 parts by mass and no greater than 80 parts by mass. An amount of the at least one second compound is no less than 25 parts by mass and no greater than 40 parts by mass.Type: GrantFiled: January 27, 2016Date of Patent: September 12, 2017Assignee: KYOCERA Document Solutions Inc.Inventors: Yuko Iwashita, Kazutaka Sugimoto, Takafumi Matsumoto
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Patent number: 9696641Abstract: An electrophotographic photosensitive member includes a photosensitive layer. The photosensitive layer contains a charge generating material and a hole transport material represented by general formula (1) shown below in a single layer. Titanyl phthalocyanine contained as the charge generating material exhibits a main peak at a Bragg angle 2?±0.2°=27.2° in a CuK? characteristic X-ray diffraction spectrum and satisfies either (B) or (C), shown below, in a differential scanning calorimetry spectrum. (B) A peak is not present in a range from 50° C. to 400° C., other than a peak resulting from vaporization of adsorbed water. (C) A peak is not present in a range from 50° C. to 270° C., other than a peak resulting from vaporization of adsorbed water, and a peak is present in a range from 270° C. to 400° C.Type: GrantFiled: January 29, 2016Date of Patent: July 4, 2017Assignee: KYOCERA Document Solutions Inc.Inventors: Yuko Iwashita, Kazutaka Sugimoto, Takafumi Matsumoto
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Publication number: 20160223921Abstract: An electrophotographic photosensitive member includes a photosensitive layer. The photosensitive layer contains a charge generating material and a hole transport material represented by general formula (1) shown below in a single layer. Titanyl phthalocyanine contained as the charge generating material exhibits a main peak at a Bragg angle 2?±0.2°=27.2° in a CuK? characteristic X-ray diffraction spectrum and satisfies either (B) or (C), shown below, in a differential scanning calorimetry spectrum. (B) A peak is not present in a range from 50° C. to 400° C., other than a peak resulting from vaporization of adsorbed water. (C) A peak is not present in a range from 50° C. to 270° C., other than a peak resulting from vaporization of adsorbed water, and a peak is present in a range from 270° C. to 400° C.Type: ApplicationFiled: January 29, 2016Publication date: August 4, 2016Applicant: KYOCERA Document Solutions Inc.Inventors: Yuko IWASHITA, Kazutaka SUGIMOTO, Takafumi MATSUMOTO
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Publication number: 20160223924Abstract: An electrophotographic photosensitive member includes a photosensitive layer. The photosensitive layer contains a charge generating material and a hole transport material. Titanyl phthalocyanine contained as the charge generating material exhibits a main peak at a Bragg angle 2?±0.2°=27.2° in a CuK? characteristic X-ray diffraction spectrum and satisfies either (B) or (C), shown below, in a differential scanning calorimetry spectrum. (B) A peak is not present in a range from 50° C. to 400° C., other than a peak resulting from vaporization of adsorbed water. (C) A peak is not present in a range from 50° C. to 270° C., other than a peak resulting from vaporization of adsorbed water, and a peak is present in a range from 270° C. to 400° C. The hole transport material is a compound represented by general formula (1).Type: ApplicationFiled: January 29, 2016Publication date: August 4, 2016Applicant: KYOCERA Document Solutions Inc.Inventors: Yuko IWASHITA, Kazutaka SUGIMOTO, Takafumi MATSUMOTO
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Publication number: 20160223923Abstract: An electrophotographic photosensitive member includes a single-layer type photosensitive layer including phthalocyanine or a derivative thereof and an electron transport material. The electron transport material includes at least one first compound represented by formula (1) or (2) shown below and at least one second compound represented by formula (3), (4), or (5) shown below. A total amount of the at least one first compound and the at least one second compound is no less than 60 parts by mass and no greater than 120 parts by mass relative to 100 parts by mass of the binder resin. An amount of the at least one first compound is no less than 35 parts by mass and no greater than 80 parts by mass. An amount of the at least one second compound is no less than 25 parts by mass and no greater than 40 parts by mass.Type: ApplicationFiled: January 27, 2016Publication date: August 4, 2016Applicant: KYOCERA Document Solutions Inc.Inventors: Yuko IWASHITA, Kazutaka SUGIMOTO, Takafumi MATSUMOTO
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Patent number: 9213229Abstract: A positively chargeable electrophotographic photosensitive member has a photosensitive layer. The photosensitive layer at least includes the following layers layered in the stated order: (I) a charge transport layer at least containing a hole transport material and a binder resin; and (II) a charge generating-and-transporting layer at least containing a charge generating material, an electron transport material, a hole transport material, and a binder resin all within this layer. The binder resin contained in the charge transport layer is different from the binder resin contained in the charge generating-and-transporting layer, and either of the binder resins contains a polyvinyl acetal resin.Type: GrantFiled: January 30, 2014Date of Patent: December 15, 2015Assignee: KYOCERA Document Solutions Inc.Inventors: Yuko Iwashita, Yukimasa Watanabe, Junichiro Otsubo, Kazuaki Ezure, Kazutaka Sugimoto
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Patent number: 9158264Abstract: A single-layer-type electrophotographic photosensitive member includes a layer disposed on an electrically conductive substrate, the layer including at least a charge-generating material, an electron transport material, a hole transport material, and a binder resin within the same layer. The charge-generating material contains a phthalocyanine pigment and N-type pigments including at least a perylene-based pigment and an azo-based pigment, and the total amount of the N-type pigments is 0.03 to 10 parts by mass relative to 1 part by mass of the phthalocyanine pigment.Type: GrantFiled: October 31, 2013Date of Patent: October 13, 2015Assignee: Kyocera Document Solutions Inc.Inventors: Yuko Iwashita, Kazutaka Sugimoto, Junichiro Otsubo, Yukimasa Watanabe, Kazuaki Edure
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Patent number: 9141007Abstract: Provided is a monolayer type photoconductor superior in sensitivity characteristics that allows reliable production by easy confirmation of the sensitivity characteristics, and an image forming device using such a monolayer type photoconductor. A monolayer type photoconductor including a base body and a single photo sensitive layer formed on the base body, the single photo sensitive layer containing a charge generating agent, a hole transfer agent, an electron transfer agent and a binding resin, wherein a maximum absorption wavelength (?max) of the photo sensitive layer is set to a value of below 850 nm and an absorbance (A850) of light at a wavelength of 850 nm per unit thickness of the photo sensitive layer is set to a value of 0.05 ?m?1 or less.Type: GrantFiled: March 13, 2008Date of Patent: September 22, 2015Assignee: Kyocera Mita CorporationInventors: Kazunari Hamasaki, Yuko Iwashita, Daisuke Kuboshima, Keiji Maruo, Shiho Kuboshima
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Publication number: 20140212803Abstract: A positively chargeable electrophotographic photosensitive member has a photosensitive layer. The photosensitive layer at least includes the following layers layered in the stated order: (I) a charge transport layer at least containing a hole transport material and a binder resin; and (II) a charge generating-and-transporting layer at least containing a charge generating material, an electron transport material, a hole transport material, and a binder resin all within this layer. The binder resin contained in the charge transport layer is different from the binder resin contained in the charge generating-and-transporting layer, and either of the binder resins contains a polyvinyl acetal resin.Type: ApplicationFiled: January 30, 2014Publication date: July 31, 2014Applicant: KYOCERA DOCUMENT SOLUTIONS INC.Inventors: Yuko IWASHITA, Yukimasa WATANABE, Junichiro OTSUBO, Kazuaki EZURE, Kazutaka SUGIMOTO
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Publication number: 20140120464Abstract: A single-layer-type electrophotographic photosensitive member includes a layer disposed on an electrically conductive substrate, the layer including at least a charge-generating material, an electron transport material, a hole transport material, and a binder resin within the same layer. The charge-generating material contains a phthalocyanine pigment and N-type pigments including at least a perylene-based pigment and an azo-based pigment, and the total amount of the N-type pigments is 0.03 to 10 parts by mass relative to 1 part by mass of the phthalocyanine pigment.Type: ApplicationFiled: October 31, 2013Publication date: May 1, 2014Applicant: Kyocera Document Solutions Inc.Inventors: Yuko Iwashita, Kazutaka Sugimoto, Junichiro Otsubo, Yukimasa Watanabe, Kazuaki Edure