Patents by Inventor Shuhei Iwasaki
Shuhei Iwasaki 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: 20240118655Abstract: An object of the present disclosure is to provide an electrophotographic photosensitive member with suppressed positive ghosts, and a process cartridge and an electrophotographic apparatus each including the electrophotographic photosensitive member. The present disclosure provides an electrophotographic photosensitive member having a support and a photosensitive layer on the support; the photosensitive layer comprises (?) a compound represented by the formula (1), and (?) at least one selected from the group consisting of a compound represented by the formula (2) and a compound represented by the formula (3), wherein a content of the (?) with respect to a content of the (?) is 50 to 850 mass ppm in the photosensitive layer.Type: ApplicationFiled: September 8, 2023Publication date: April 11, 2024Inventors: KUNIHIKO SEKIDO, SHUHEI IWASAKI, TATSUYA OHSAWA, NAOYUKI MATSUMOTO, ATSUSHI OKUDA, TSUTOMU NISHIDA
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Publication number: 20240118633Abstract: An electrophotographic photosensitive member including: a support, a charge generating layer, and a charge transporting layer in this order, wherein the charge transporting layer contains: a compound represented by the formula (A-1), and at least one selected from the group consisting of a compound represented by the formula (A-2) and a compound represented by the formula (A-3).Type: ApplicationFiled: September 8, 2023Publication date: April 11, 2024Inventors: TATSUYA OHSAWA, KUNIHIKO SEKIDO, SHUHEI IWASAKI, NAOYUKI MATSUMOTO
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Publication number: 20240111224Abstract: An object of the present disclosure is to provide an electrophotographic photosensitive member which can suppress the potential fluctuation due to repeated use even with the electrophotographic apparatus of high printing process speed. The present disclosure provides an electrophotographic photosensitive member comprising: a support, a charge generating layer, and a charge transporting layer in this order, wherein the charge transporting layer comprises: (?) a compound represented by the formula (C-1), and (?) at least one selected from the group consisting of a compound represented by the following formula (C-2) and a compound represented by the formula (C-3), wherein a content of the (?) in the charge transporting layer with respect to a total mass of the charge transporting layer is 250 to 610 mass ppm.Type: ApplicationFiled: September 8, 2023Publication date: April 4, 2024Inventors: SHUHEI IWASAKI, KUNIHIKO SEKIDO, TATSUYA OHSAWA, NAOYUKI MATSUMOTO
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Patent number: 11947275Abstract: Provided is an electrophotographic apparatus including: an electrophotographic photosensitive member; a voltage application unit configured to cause discharge from an electroconductive member to the electrophotographic photosensitive member; a charge transfer amount detection unit configured to detect a charge transfer amount per unit time resulting from the discharge from the electroconductive member to the electrophotographic photosensitive member; and a charging potential control unit, wherein V1 and V2 defined by specific procedures for the electrophotographic photosensitive member satisfy a relationship represented by the following expression (E-4): 100V1<V2?V1 (E-4), and wherein the charging potential control unit is configured to control the charging potential of the electrophotographic photosensitive member at the time of image formation.Type: GrantFiled: February 14, 2023Date of Patent: April 2, 2024Assignee: CANON KABUSHIKI KAISHAInventors: Shuhei Iwasaki, Kaname Watariguchi, Akihiro Maruyama, Kenichi Kaku, Michiyo Sekiya, Kohei Makisumi, Tatsuya Yamaai, Hideharu Shimozawa, Naoki Fukushima
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Publication number: 20240049592Abstract: In order to provide a photoelectric conversion element having higher photoelectric conversion efficiency, in a photoelectric conversion element having a first electrode, a second electrode, and a photoelectric conversion layer containing an organic-inorganic perovskite compound and disposed between the first electrode and the second electrode, a particle layer including particles that mainly contain a phthalocyanine compound is arranged between the photoelectric conversion layer and the first electrode.Type: ApplicationFiled: October 18, 2023Publication date: February 8, 2024Inventors: HIROYUKI WATANABE, SHUNTARO WATANABE, KENICHI KAKU, JUMPEI KUNO, AKIHIRO MARUYAMA, SHUHEI IWASAKI, KOHEI MAKISUMI, YUNA YAMAMOTO
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Patent number: 11782353Abstract: A method for producing an electrophotographic photosensitive member including: forming a photosensitive layer; and forming a protective layer, wherein the step of forming the photosensitive layer forms a photosensitive layer having an amount of residual solvent of a first solvent in the photosensitive layer of 0.05% to 2.50% and an amount of residual solvent of a second solvent in the photosensitive layer of 0.50% to 2.50%, and the step of forming the protective layer includes step (A) of forming a cured film and step (B) of forming the protective layer having wrinkle shapes, wherein, in step (A), the irradiated coating film is heated at a heating temperature lower than a boiling point of the first solvent and in step (B), the cured film is heated at a heating temperature higher than a boiling point of the first solvent.Type: GrantFiled: April 13, 2021Date of Patent: October 10, 2023Assignee: CANON KABUSHIKI KAISHAInventors: Nobuhiro Nakamura, Tomohito Ishida, Shuhei Iwasaki, Hiroyuki Watanabe, Tatsuya Yamaai, Yuka Ishiduka, Yota Ito, Takeshi Murakami
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Publication number: 20230288836Abstract: Provided is an electrophotographic apparatus including: an electrophotographic photosensitive member; a voltage application unit configured to cause discharge from an electroconductive member to the electrophotographic photosensitive member; a charge transfer amount detection unit configured to detect a charge transfer amount per unit time resulting from the discharge from the electroconductive member to the electrophotographic photosensitive member; and a charging potential control unit, wherein V1 and V2 defined by specific procedures for the electrophotographic photosensitive member satisfy a relationship represented by the following expression (E-4): 100V1<V2?V1 (E-4), and wherein the charging potential control unit is configured to control the charging potential of the electrophotographic photosensitive member at the time of image formation.Type: ApplicationFiled: February 14, 2023Publication date: September 14, 2023Inventors: SHUHEI IWASAKI, KANAME WATARIGUCHI, AKIHIRO MARUYAMA, KENICHI KAKU, MICHIYO SEKIYA, KOHEI MAKISUMI, TATSUYA YAMAAI, HIDEHARU SHIMOZAWA, NAOKI FUKUSHIMA
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Patent number: 11619907Abstract: A process cartridge including: an electrophotographic photosensitive member having a drum shape; a developing unit for developing an electrostatic latent image on the surface of the electrophotographic photosensitive member with toner; and a cleaning blade for removing the toner on the surface of the electrophotographic photosensitive member, the cleaning blade being in contact with the electrophotographic photosensitive member, wherein the electrophotographic photosensitive member comprises wrinkles on the surface of the electrophotographic photosensitive member, and wherein the toner has a fluidity torque E of 320 mJ or more.Type: GrantFiled: March 8, 2022Date of Patent: April 4, 2023Assignee: Canon Kabushiki KaishaInventors: Fumiyuki Hiyama, Shuhei Iwasaki, Hiroyuki Watanabe, Nobuhiro Nakamura, Tomohito Ishida, Shuntaro Watanabe
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Publication number: 20230059773Abstract: An electrophotographic photosensitive member includes: a support; an undercoat layer; a charge generation layer; and a charge transport layer, wherein the undercoat layer contains a polyamide resin and a titanium oxide fine particle, and on the surface of the undercoat layer, an arithmetic mean roughness Ra and an average length Rsm of a roughness curve element both according to JIS B0601:2001 satisfy Ra?50 nm and 0.1?Ra/Rsm?0.5; and the charge generation layer contains a hydroxygallium phthalocyanine pigment, wherein the hydroxygallium phthalocyanine pigment includes crystal particles having a crystal form exhibiting peaks at 7.4°±0.3° and 28.2°±0.3° at Bragg angles 2? in a spectrum of X-ray diffraction using a CuK?, ray; and in a size distribution of the crystal particles, which is measured using small-angle X-ray scattering, a peak exists in a range of 20 to 50 nm, and the peak has a half-value width of 50 nm or smaller.Type: ApplicationFiled: July 25, 2022Publication date: February 23, 2023Inventors: Tatsuya Yamaai, Kaname Watariguchi, Kenichi Kaku, Shuhei Iwasaki, Akihiro Maruyama
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Publication number: 20230059041Abstract: Provided is an electrophotographic apparatus which uses a light emitting diode array as an exposure unit and exposes a photosensitive member to a quantity of light from the LED array whose average light quantity satisfies 0.8×Emin or more and 1.1×Emin or less on condition that a normalized radius of curvature R of a normalized graph derived from the E-V curve of the photosensitive member has a minimum value of 0.24 or less, and a light quantity at the minimum value of the normalized radius of curvature R is Emin [?J/cm2]. This electrophotographic apparatus prevents both the occurrence of image unevenness due to light quantity variation among the elements of the LED array and the generation of ghost images due to a rest potential.Type: ApplicationFiled: July 29, 2022Publication date: February 23, 2023Inventors: Kenichi Kaku, Akihiro Maruyama, Shuhei Iwasaki, Tatsuya Yamaai, Kaname Watariguchi, Michiyo Sekiya, Kohei Makisumi, Hideharu Shimozawa
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Publication number: 20230058278Abstract: The electrophotographic apparatus includes: an electrophotographic photosensitive member; a charging unit; an image-exposing unit; a charge transfer amount-sensing unit for sensing the amount of charge transferred to the electrophotographic photosensitive member; and an exposed portion potential-controlling unit for controlling the potential of each of the exposed portions of the electrophotographic photosensitive member based on a sensing result, which is obtained by charging the electrophotographic photosensitive member with the charging unit, performing image exposure with the image-exposing unit in at least one light amount weaker than a light amount in which the normalized radius of curvature R of the electrophotographic photosensitive member represented by the following equation (E1), the normalized radius of curvature being obtained by a method of measuring an EV curve, shows a minimum, and in at least two light amounts stronger than the light amount in which the normalized radius of curvature shows thType: ApplicationFiled: July 27, 2022Publication date: February 23, 2023Inventors: Akihiro Maruyama, Kenichi Kaku, Shuhei Iwasaki, Kohei Makisumi, Michiyo Sekiya, Kaname Watariguchi, Hideharu Shimozawa, Tatsuya Yamaai, Takanori Mitani, Satoshi Nishida
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Publication number: 20220291627Abstract: A process cartridge including: an electrophotographic photosensitive member having a drum shape; a developing unit for developing an electrostatic latent image on the surface of the electrophotographic photosensitive member with toner; and a cleaning blade for removing the toner on the surface of the electrophotographic photosensitive member, the cleaning blade being in contact with the electrophotographic photosensitive member, wherein the electrophotographic photosensitive member comprises wrinkles on the surface of the electrophotographic photosensitive member, and wherein the toner has a fluidity torque E of 320 mJ or more.Type: ApplicationFiled: March 8, 2022Publication date: September 15, 2022Inventors: Fumiyuki Hiyama, Shuhei Iwasaki, Hiroyuki Watanabe, Nobuhiro Nakamura, Tomohito Ishida, Shuntaro Watanabe
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Publication number: 20220291600Abstract: In an electrophotographic photosensitive member, wrinkles have a convex portion in which a linear shape portion having a length of 50 ?m or longer exists, the linear shape portion is parallel to any one of L1 to L150 and L1651 to L1800, and each of L1 to L1800 intersects with the convex portion at a plurality of places, and at least two of the places have different intersection angles; and when height information of the wrinkles is subjected to a frequency analysis, and a two-dimensional power spectrum is obtained, a one-dimensional radial distribution function has at least one local maximum value, and when an angular distribution is calculated from the spectrum at a frequency of the local maximum value, the power values have a particular relationship.Type: ApplicationFiled: March 4, 2022Publication date: September 15, 2022Inventors: Nobuhiro Nakamura, Tomohito Ishida, Shuhei Iwasaki, Hiroyuki Watanabe, Fumiyuki Hiyama, Shuntaro Watanabe
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Patent number: 11392074Abstract: Provided is an electrophotographic photosensitive drum that achieves both of a reduction in torque of the electrophotographic photosensitive drum at the time of its cleaning and an improvement in image transferability. The electrophotographic photosensitive drum includes: a support; and a photosensitive layer arranged on the support, the electrophotographic photosensitive drum having arranged on an outer surface thereof at least two structure groups having different appearance periods, wherein when, out of the two structure groups, a group including structures having a smaller appearance period is defined as a first structure group, and a group including structures having a larger appearance period is defined as a second structure group, a height of the first structure group is lower than a height of the second structure group.Type: GrantFiled: April 13, 2021Date of Patent: July 19, 2022Assignee: CANON KABUSHIKI KAISHAInventors: Tomohito Ishida, Nobuhiro Nakamura, Shuhei Iwasaki, Hiroyuki Watanabe, Tatsuya Yamaai, Yuka Ishiduka, Yota Ito, Takeshi Murakami
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Publication number: 20210325814Abstract: Provided is an electrophotographic photosensitive drum that achieves both of a reduction in torque of the electrophotographic photosensitive drum at the time of its cleaning and an improvement in image transferability. The electrophotographic photosensitive drum includes: a support; and a photosensitive layer arranged on the support, the electrophotographic photosensitive drum having arranged on an outer surface thereof at least two structure groups having different appearance periods, wherein when, out of the two structure groups, a group including structures having a smaller appearance period is defined as a first structure group, and a group including structures having a larger appearance period is defined as a second structure group, a height of the first structure group is lower than a height of the second structure group.Type: ApplicationFiled: April 13, 2021Publication date: October 21, 2021Inventors: Tomohito Ishida, Nobuhiro Nakamura, Shuhei Iwasaki, Hiroyuki Watanabe, Tatsuya Yamaai, Yuka lshiduka, Yota Ito, Takeshi Murakami
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Publication number: 20210325793Abstract: A method for producing an electrophotographic photosensitive member including: forming a photosensitive layer; and forming a protective layer, wherein the step of forming the photosensitive layer forms a photosensitive layer having an amount of residual solvent of a first solvent in the photosensitive layer of 0.05% to 2.50% and an amount of residual solvent of a second solvent in the photosensitive layer of 0.50% to 2.50%, and the step of forming the protective layer includes step (A) of forming a cured film and step (B) of forming the protective layer having wrinkle shapes, wherein, in step (A), the irradiated coating film is heated at a heating temperature lower than a boiling point of the first solvent and in step (B), the cured film is heated at a heating temperature higher than a boiling point of the first solvent.Type: ApplicationFiled: April 13, 2021Publication date: October 21, 2021Inventors: Nobuhiro Nakamura, Tomohito Ishida, Shuhei Iwasaki, Hiroyuki Watanabe, Tatsuya Yamaai, Yuka lshiduka, Yota Ito, Takeshi Murakami
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Publication number: 20210325794Abstract: There is provided an electrophotographic photosensitive member having drum shape, the electrophotographic photosensitive member including a support and a photosensitive layer, wherein an outer surface of the electrophotographic photosensitive member has wrinkles, and when an observation region having square form with one side of 100 ?m is placed at an arbitrary position on the outer surface, a line that passes through a central point of the observation region and is parallel to a circumferential direction of the electrophotographic photosensitive member is defined as a first reference line L1, and 3,599 reference lines obtained by rotating the first reference line L1 at every 0.1° around the central point are defined as L2 to L3,600, respectively, each of L1 to L3,600 intersects with convex portions of the wrinkles at a plurality of locations and has at least two different intersection angles selected from the plurality of locations.Type: ApplicationFiled: April 14, 2021Publication date: October 21, 2021Inventors: Shuhei Iwasaki, Tomohito Ishida, Nobuhiro Nakamura, Hiroyuki Watanabe, Tatsuya Yamaai, Yuka Ishiduka, Yota Ito, Takeshi Murakami
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Patent number: 11150566Abstract: The present disclosure provides an electrophotographic photosensitive member that can simultaneously achieve the suppression of the occurrence of the black spot in a charged portion and the suppression of the deterioration in sensitivity of an exposed portion, even after stored in a high-temperature and high-humidity environment. An electrophotographic photosensitive member includes an electro-conductive support, an undercoat layer, a charge generation layer and a charge transport layer in this order, wherein an atomic concentration ratio R of the oxygen atom to the aluminum atom on the surface of the electro-conductive support, as measured by energy dispersive X-ray spectroscopy, satisfies the following Expression (1): 1.6?R??(1) and the undercoat layer includes a titanium oxide particle that is surface-treated with a particular silane compound.Type: GrantFiled: June 3, 2020Date of Patent: October 19, 2021Assignee: CANON KABUSHIKI KAISHAInventors: Shuhei Iwasaki, Akira Sakakibara, Jumpei Kuno, Yota Ito, Kohei Makisumi
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Patent number: 11086241Abstract: An electrophotographic photoreceptor includes a support, an undercoat layer placed on the support, a charge generation layer placed on the undercoat layer, and a charge transport layer placed on the charge generation layer. The undercoat layer contains titanium oxide particles surface-treated with an organosilicon compound that is at least one member selected from the group consisting of compounds represented by formulas (1) to (8) and a polyamide resin. The charge generation layer contains hydroxygallium phthalocyanine.Type: GrantFiled: February 11, 2020Date of Patent: August 10, 2021Assignee: Canon Kabushiki KaishaInventors: Jumpei Kuno, Akira Sakakibara, Yota Ito, Shuhei Iwasaki, Kohei Makisumi
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Patent number: 10942462Abstract: The present disclosure provides an electrophotographic photosensitive member that reduces the accumulation of charge and the leakage which are caused by a repeated use in a long period of time. The electrophotographic photosensitive member has a support, an undercoat layer, a charge generation layer and a charge transport layer in this order, wherein the undercoat layer contains a polyamide resin, and a titanium oxide particle, wherein the titanium oxide particle has been surfacetreated with an organosilicon compound, wherein the undercoat layer satisfies 10???70, where ? represents a degree [%] of hydrophobicity of the titanium oxide particle which has been surfacetreated with the organosilicon compound; and the undercoat layer satisfies 0.015?(?×?)?0.040, where ? represents an average primary particle size [?m] of the titanium oxide particles, and ? represents a weight percentage [wt %] of an Si element of the organosilicon compound with respect to the titanium oxide particle.Type: GrantFiled: October 30, 2019Date of Patent: March 9, 2021Assignee: Canon Kabushiki KaishaInventors: Yota Ito, Akira Sakakibara, Jumpei Kuno, Shuhei Iwasaki, Kohei Makisumi