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).

  • 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
  • Publication number: 20190025720
    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: Application
    Filed: July 16, 2018
    Publication date: January 24, 2019
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Jun AZUMA, Kensuke KOJIMA, Tomofumi SHIMIZU
  • Publication number: 20180356744
    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: Application
    Filed: June 5, 2018
    Publication date: December 13, 2018
    Applicant: KYOCERA Document Solutions Inc.
    Inventor: Tomofumi SHIMIZU
  • Publication number: 20180356743
    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: Application
    Filed: June 8, 2018
    Publication date: December 13, 2018
    Applicant: KYOCERA Document Solutions Inc.
    Inventor: Tomofumi SHIMIZU
  • Publication number: 20180299797
    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: Application
    Filed: April 9, 2018
    Publication date: October 18, 2018
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi SHIMIZU, Jun AZUMA
  • Publication number: 20180246424
    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: Application
    Filed: February 26, 2018
    Publication date: August 30, 2018
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Jun AZUMA, Kensuke OKAWA, Akihiko OGATA, Kenji KITAGUCHI, Tomofumi SHIMIZU
  • Publication number: 20180215183
    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: Application
    Filed: January 25, 2018
    Publication date: August 2, 2018
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi SHIMIZU, Kiichiro OJI
  • Patent number: 10007199
    Abstract: A single-layer electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The conductive substrate contains aluminum or an aluminum alloy. A surface of the conductive substrate has an aluminum oxide film or an aluminum alloy oxide film. The photosensitive layer is disposed directly on the conductive substrate. The photosensitive layer contains an electron transport material. The electron transport material has a reduction potential of at least ?0.88 V and no greater than ?0.66 V versus a reference electrode (Ag/Ag+). The single-layer electrophotographic photosensitive member has a leakage onset voltage of at least 5.0 kV in a high temperature and humidity environment at a temperature of 30° C. and a relative humidity of 80%. The leakage onset voltage is a voltage applied to the single-layer electrophotographic photosensitive member at which current leakage starts.
    Type: Grant
    Filed: August 26, 2016
    Date of Patent: June 26, 2018
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi Shimizu, Junichiro Otsubo, Yasuhiro Oishi
  • Patent number: 10001716
    Abstract: A positively chargeable single-layer electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer contains at least a charge generating material, a hole transport material, an electron transport material, and an electron accepting compound. The hole transport material includes a benzidine derivative. The electron transport material includes at least one compound selected from the group consisting of compounds represented by general formulae (1), (2), (3), and (4) shown below. The electron accepting compound includes at least one compound selected from the group consisting of compounds represented by general formulae (5) and (6) shown below.
    Type: Grant
    Filed: March 22, 2016
    Date of Patent: June 19, 2018
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Tomofumi Shimizu, Makoto Shishido