Patents by Inventor Tomofumi SHIMIZU

Tomofumi SHIMIZU 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: 10635009
    Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer having a single-layer structure. The photosensitive layer contains a charge generating material, an electron transport material, a polycarbonate resin, and a hole transport material. The electron transport material includes a compound having a halogen atom and represented by general formula (1), (2), (3), (4), or (5). The polycarbonate resin has a terminal group having a fluoro group and represented by general formula (10). The hole transport material includes a compound represented by general formula (20), (21), (22), (23), (24), (25), (26), or (27). A charge of calcium carbonate as measured by charging the calcium carbonate through friction with the photosensitive layer is at least +6.5 ?C/g. The photosensitive layer has a Vickers hardness of at least 17.0 HV at 45° C.
    Type: Grant
    Filed: June 8, 2018
    Date of Patent: April 28, 2020
    Assignee: KYOCERA Document Solutions Inc.
    Inventor: Tomofumi Shimizu
  • Publication number: 20200117106
    Abstract: A compound mixture contains a mixture of a compound represented by general formula (1) and a compound represented by general formula (2). In the general formula (1), R1A, R2A, R3A, R4A, R5A, R6A, R7A, R8A, R9A, and R10A each represent, independently of one another, a hydrogen atom, an alkyl group having a carbon number of at least 1 and no greater than 8, an alkoxy group having a carbon number of at least 1 and no greater than 8, or an aryl group having a carbon number of at least 6 and no greater than 14.
    Type: Application
    Filed: October 4, 2019
    Publication date: April 16, 2020
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Jun AZUMA, Kensuke KOJIMA, Tomofumi SHIMIZU
  • Patent number: 10545418
    Abstract: An electrophotographic photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3). The photosensitive layer (3) is a single-layer photosensitive layer containing at least a charge generating material, an electron transport material, a hole transport material, and a binder resin. The electron transport material includes a naphthoquinone derivative represented by general formula (1). An amount of triboelectric charge of calcium carbonate as measured by charging the calcium carbonate through friction with the photosensitive layer (3) is at least +7 ?C/g. In general formula (1), R11 and R12 are respectively the same as R11 and R12 described in the description.
    Type: Grant
    Filed: March 17, 2017
    Date of Patent: January 28, 2020
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi Shimizu, Hideki Okada
  • Patent number: 10509337
    Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer having a single-layer structure. The photosensitive layer contains a charge generating material, an electron transport material, a polycarbonate resin, and a hole transport material. The electron transport material includes a compound having a halogen atom and represented by general formula (1), (2), (3), (4), or (5). The hole transport material includes a compound represented by general formula (20), (21), (22), (23), (24), (25), (26), or (27). A charge of calcium carbonate as measured by charging the calcium carbonate through friction with the photosensitive layer is at least +6.5 ?C/g. A Vickers hardness of the photosensitive layer at 45° C. is at least 17.0 HV.
    Type: Grant
    Filed: June 5, 2018
    Date of Patent: December 17, 2019
    Assignee: KYOCERA Document Solutions Inc.
    Inventor: Tomofumi Shimizu
  • Publication number: 20190354027
    Abstract: An electrophotographic photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3). The photosensitive layer (3) is a single-layer photosensitive layer (3c) and contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The binder resin includes a polyarylate resin represented by general formula (1). In general formula (1), Q1, Q2, Q3, and Q4 each represent a methyl group or a hydrogen atom. r, s, t, and u each represent a number greater than or equal to 15 and less than or equal to 35.
    Type: Application
    Filed: November 30, 2017
    Publication date: November 21, 2019
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi SHIMIZU, Jun AZUMA, Keiji MARUO
  • Publication number: 20190354029
    Abstract: A method for producing an electrophotographic photosensitive member includes an electrically conductive substrate and a photosensitive layer. The method includes applying an application liquid for photosensitive layer formation containing a solvent, a binder resin, and a hole transport material directly or indirectly onto the electrically conductive substrate, and removing a portion of the solvent, to form the photosensitive layer. The solvent contains a first solvent that is an alcohol having a carbon number of at least 1 and no greater than 3, and a second solvent other than the first solvent.
    Type: Application
    Filed: May 14, 2019
    Publication date: November 21, 2019
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Jun AZUMA, Tomofumi SHIMIZU, Kenji KITAGUCHI, Kiichiro OJI
  • Publication number: 20190354028
    Abstract: A method of manufacturing an electrographic photoreceptor provided with a conductive substrate and a single-layered photosensitive layer is disclosed. The method includes: directly or indirectly applying a coating liquid for photosensitive layer formation onto the conductive substrate, the coating liquid containing a solvent, a charge generating agent, a binder resin, a hole transport material and an electron transport material; and removing part of the solvent to form the single-layered photosensitive layer. The solvent includes a first solvent as an alcohol with 1 to 3 carbon atoms and a second solvent as a solvent other than the first solvent. The binder resin includes a polyarylate resin as a polymerized product of monomers including a first monomer represented by General Formula (1) below and a second monomer represented by General Formula (2) below. The electron transport material includes a compound represented by General Formula (31), (32), (33) or (34) below.
    Type: Application
    Filed: May 2, 2019
    Publication date: November 21, 2019
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi SHIMIZU, Jun AZUMA
  • Patent number: 10481511
    Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single-layer photosensitive layer and contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The binder resin has a viscosity average molecular weight of at least 25,000 and no greater than 50,000. A strain at break of the photosensitive layer is at least 4.9% and no greater than 13.0%. A scratch resistant depth of the photosensitive layer is no greater than 0.50 ?m.
    Type: Grant
    Filed: July 16, 2018
    Date of Patent: November 19, 2019
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi Shimizu, Kiichiro Oji
  • Publication number: 20190332023
    Abstract: An electrophotographic photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3). The photosensitive layer (3) is a single-layer photosensitive layer (3c) and contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The binder resin includes a polyarylate resin represented by general formula (1). In general formula (1), Q1, Q2, Q3, and Q4 each represent a methyl group or a hydrogen atom. r, s, t, and u each represent a number greater than or equal to 15 and less than or equal to 35.
    Type: Application
    Filed: November 30, 2017
    Publication date: October 31, 2019
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi SHIMIZU, Keiji MARUO, Jun AZUMA
  • Publication number: 20190317414
    Abstract: An electrophotographic photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3). The photosensitive layer (3) is a single-layer photosensitive layer (3c) containing a charge generating material and an electron transport material. The electron transport material includes a compound represented by general formula (1) shown below. An amount of charge of calcium carbonate as measured by charging the calcium carbonate through friction with the photosensitive layer (3) is at least +7.0 ?C/g. In general formula (1), R1 and R2 each represent, independently of each other, a halogen atom, for example. Further, m, n, and Y are as described in the description.
    Type: Application
    Filed: April 27, 2017
    Publication date: October 17, 2019
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi SHIMIZU, Hideki OKADA
  • Patent number: 10379451
    Abstract: A polyarylate resin includes at least one type of repeating unit represented by a general formula (1), at least one type of repeating unit represented by a general formula (2), and a terminal group represented by a general formula (3). R1, R2, R3, and R4 each represent, independently of one another, a hydrogen atom or a methyl group. R5 and R6 each represent, independently of each other, a hydrogen atom or a C1-4 alkyl group. R5 and R6 may bond together to represent a C5-7 cycloalkylidene group. X1 represents a divalent group represented by a chemical formula (2A), (2B), (2C), or (2D) with the proviso that when only one type of repeating unit represented by the general formula (2) is included, X1 does not represent a divalent group represented by the chemical formula (2D). Rf represents a chain aliphatic group having at least one fluoro group.
    Type: Grant
    Filed: February 26, 2018
    Date of Patent: August 13, 2019
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Jun Azuma, Kensuke Okawa, Akihiko Ogata, Kenji Kitaguchi, Tomofumi Shimizu
  • Patent number: 10372047
    Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single-layer photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, a binder resin, and an additive. The additive contains a carboxylic acid anhydride. A reduction potential of the carboxylic acid anhydride is at least ?1.40 V versus a reference electrode (Ag/Ag+). The carboxylic acid anhydride is contained in an amount of at least 0.02 parts by mass and no greater than 10.00 parts by mass relative to 100 parts by mass of the binder resin.
    Type: Grant
    Filed: January 25, 2018
    Date of Patent: August 6, 2019
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi Shimizu, Kiichiro Oji
  • Patent number: 10372048
    Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer includes a charge generating layer and a charge transport layer. The charge generating layer contains a charge generating material. The charge transport layer contains a hole transport material and a binder resin. The charge transport layer further contains an electron acceptor compound. The hole transport material includes a compound represented by general formula (1). In general formula (1), R1, R2, R3, R4, R5, R6, R7, R8, R9, and R10 each represent, independently of one another, a hydrogen atom or a methyl group.
    Type: Grant
    Filed: July 16, 2018
    Date of Patent: August 6, 2019
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Jun Azuma, Kensuke Kojima, Tomofumi Shimizu
  • Patent number: 10359713
    Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer having a single-layer structure. The photosensitive layer contains a charge generating material, an electron transport material, and a binder resin. The electron transport material includes a compound having a halogen atom and represented by a general formula (1), (2), (3), (4), or (5). The binder resin includes a polyarylate resin. The polyarylate resin includes at least one type of repeating unit each represented by general formula (11), at least one type of repeating unit each represented by general formula (12), and a terminal group represented by general formula (13). In general formula (13), Rf represents a chain aliphatic group substituted by at least one fluoro group. A charge of calcium carbonate charged by friction between the photosensitive layer and the calcium carbonate is at least +8.0 ?C/g.
    Type: Grant
    Filed: April 9, 2018
    Date of Patent: July 23, 2019
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi Shimizu, Jun Azuma
  • Patent number: 10295918
    Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single-layer photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The binder resin contains a polyarylate resin (1). The polyarylate resin is represented by general formula (1). The photosensitive layer has a scratch resistance depth of no greater than 0.50 ?m. The photosensitive layer has a Vickers hardness of at least 17.0 HV.
    Type: Grant
    Filed: August 3, 2017
    Date of Patent: May 21, 2019
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi Shimizu, Keiji Maruo, Jun Azuma
  • Patent number: 10273331
    Abstract: A polyarylate resin is represented by general formula (1) shown below. In general formula (1), R1 and R2 each represent, independently of one another, a hydrogen atom or a methyl group. r and s each represent an integer of at least 0 and no greater than 49. t and u each represent an integer of at least 1 and no greater than 50. r+s+t+u=100. r+t=s+u. X and Y each represent, independently of one another, a divalent group represented by chemical formula (1-1), chemical formula (1-2), chemical formula (1-3), or chemical formula (1-4). X and Y are different from one another.
    Type: Grant
    Filed: November 28, 2017
    Date of Patent: April 30, 2019
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Jun Azuma, Kenji Kitaguchi, Kensuke Okawa, Seiki Hasunuma, Tomofumi Shimizu
  • Patent number: 10241428
    Abstract: 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 photosensitive layer has a scratch resistance depth of no greater than 0.50 ?m.
    Type: Grant
    Filed: August 3, 2017
    Date of Patent: March 26, 2019
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi Shimizu, Keiji Maruo
  • Publication number: 20190086825
    Abstract: An electrophotographic photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3). The photosensitive layer (3) is a single-layer photosensitive layer containing at least a charge generating material, an electron transport material, a hole transport material, and a binder resin. The electron transport material includes a naphthoquinone derivative represented by general formula (1). An amount of triboelectric charge of calcium carbonate as measured by charging the calcium carbonate through friction with the photosensitive layer (3) is at least +7 ?C/g. In general formula (1), R11 and R12 are respectively the same as R11 and R12 described in the description.
    Type: Application
    Filed: March 17, 2017
    Publication date: March 21, 2019
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi SHIMIZU, Hideki OKADA
  • Patent number: 10191397
    Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single-layer photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The binder resin contains a polyarylate resin. The polyarylate resin is represented by general formula (1). The hole transport material contains a compound represented by general formula (HTM1), (HTM2), (HTM3), (HTM4), (HTM5), (HTM6), or (HTM7). The photosensitive layer has a scratch resistance depth of no greater than 0.50 ?m. The photosensitive layer has a Vickers hardness of at least 17.0 HV.
    Type: Grant
    Filed: August 4, 2017
    Date of Patent: January 29, 2019
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Keiji Maruo, Tomofumi Shimizu, Jun Azuma
  • Publication number: 20190025721
    Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single-layer photosensitive layer and contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The binder resin has a viscosity average molecular weight of at least 25,000 and no greater than 50,000. A strain at break of the photosensitive layer is at least 4.9% and no greater than 13.0%. A scratch resistant depth of the photosensitive layer is no greater than 0.50 ?m.
    Type: Application
    Filed: July 16, 2018
    Publication date: January 24, 2019
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi SHIMIZU, Kiichiro OJI