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: 10996575
    Abstract: A photosensitive layer included in an electrophotographic photosensitive member contains at least a charge generating material, a hole transport material, and a binder resin. The hole transport material includes a compound (1). The binder resin includes a polyarylate resin having at least one repeating unit (10) and at least one repeating unit (11). Alternatively, the binder resin includes a polycarbonate resin having a repeating unit (20) and a repeating unit (21).
    Type: Grant
    Filed: January 10, 2020
    Date of Patent: May 4, 2021
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi Shimizu, Kazuaki Ezure, Hayase Yamamoto, Jun Azuma
  • Publication number: 20200356018
    Abstract: 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 binder resin, a hole transport material, and an electron transport material. The binder resin includes a polyester resin and a polycarbonate resin. The polyester resin includes a first repeating unit represented by general formula (1) shown below and a second repeating unit represented by general formula (2) shown below. The polycarbonate resin includes a third repeating unit represented by general formula (3) shown below and a fourth repeating unit represented by general formula (24) shown below. A content percentage of the polyester resin in the photosensitive layer is at least 0.3% by mass and no greater than 7.0% by mass.
    Type: Application
    Filed: May 5, 2020
    Publication date: November 12, 2020
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi SHIMIZU, Kazuaki EZURE, Hayase YAMAMOTO
  • Publication number: 20200356017
    Abstract: 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 binder resin, a hole transport material, and an electron transport material. The binder resin includes a polyester resin. The polyester resin includes a first repeating unit represented by general formula (1) shown below and a second repeating unit represented by general formula (2) shown below. A content percentage of the polyester resin in the photosensitive layer is at least 0.3% by mass and no greater than 7.0% by mass.
    Type: Application
    Filed: May 4, 2020
    Publication date: November 12, 2020
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Kazuaki EZURE, Tomofumi SHIMIZU, Hayase YAMAMOTO
  • Patent number: 10761439
    Abstract: An electrophotographic photosensitive member includes a photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, and a binder resin. The binder resin contains a polyarylate resin represented by general formula (1). In general formula (1), r and s each represent an integer of at least 0 and no greater than 49 and t and u represents an integer of at least 1 and no greater than 50. Furthermore, r+s+t+u=100 and r+t=s+u. X and Y each represent, independently of one another, a divalent group represented by chemical formula (1-1), (1-2), (1-3), or (1-4).
    Type: Grant
    Filed: August 4, 2017
    Date of Patent: September 1, 2020
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Jun Azuma, Kensuke Okawa, Seiki Hasunuma, Tomofumi Shimizu
  • Patent number: 10761441
    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: Grant
    Filed: May 14, 2019
    Date of Patent: September 1, 2020
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Jun Azuma, Tomofumi Shimizu, Kenji Kitaguchi, Kiichiro Oji
  • Patent number: 10732526
    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: Grant
    Filed: November 30, 2017
    Date of Patent: August 4, 2020
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi Shimizu, Keiji Maruo, Jun Azuma
  • Publication number: 20200233324
    Abstract: A photosensitive layer included in an electrophotographic photosensitive member contains at least a charge generating material, a hole transport material, and a binder resin. The hole transport material includes a compound (1). The binder resin includes a polyarylate resin having at least one repeating unit (10) and at least one repeating unit (11). Alternatively, the binder resin includes a polycarbonate resin having a repeating unit (20) and a repeating unit (21).
    Type: Application
    Filed: January 10, 2020
    Publication date: July 23, 2020
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi SHIMIZU, Kazuaki EZURE, Hayase YAMAMOTO, Jun AZUMA
  • Publication number: 20200231535
    Abstract: A compound is represented by general formula (1). In general formula (1), R1 and R2 each represent, independently of one another, a hydrogen atom, a methyl group, or an ethyl group, and a sum of the number of carbon atoms of the chemical group represented by R1 and the number of carbon atoms of the chemical group represented by R2 is 2. R3 and R4 each represent, independently of one another, a hydrogen atom, a methyl group, or an ethyl group, and a sum of the number of carbon atoms of the chemical group represented by R3 and the number of carbon atoms of the chemical group represented by R1 is 2. A photosensitive layer of an electrophotographic photosensitive member contains at least a charge generating material, a hole transport material, and a binder resin.
    Type: Application
    Filed: July 17, 2018
    Publication date: July 23, 2020
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Jun AZUMA, Kensuke KOJIMA, Tomofumi SHIMIZU, Hideki OKADA
  • Publication number: 20200174386
    Abstract: A single-layer photosensitive layer of an electrophotographic photosensitive member contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The charge generating material is a phthalocyanine pigment. A content percentage of the phthalocyanine pigment relative to the mass of the photosensitive layer is at least 0.70% by mass and no greater than 1.40% by mass. A film thickness of the photosensitive layer is at least 25 ?m and no greater than 32 ?m. A charge amount difference ?Q is no greater than 6.50 ?C.
    Type: Application
    Filed: June 26, 2018
    Publication date: June 4, 2020
    Applicant: KYOCERA Document Solutions Inc.
    Inventor: Tomofumi SHIMIZU
  • Patent number: 10656543
    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: Grant
    Filed: April 27, 2017
    Date of Patent: May 19, 2020
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi Shimizu, Hideki Okada
  • Patent number: 10649351
    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: Grant
    Filed: November 30, 2017
    Date of Patent: May 12, 2020
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi Shimizu, Jun Azuma, Keiji Maruo
  • 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: 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
  • 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
  • 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