Patents by Inventor Seiki HASUNUMA

Seiki HASUNUMA 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: 10871723
    Abstract: An electrophotographic photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3) disposed directly or indirectly on the conductive substrate (2). The photosensitive layer (3) has a charge generating layer (3a) and a charge transport layer (3b) disposed in order from the conductive substrate (2). The charge generating layer (3a) contains a charge generating material. The charge transport layer (3b) contains a charge transport material, a binder resin, and a pigment that absorbs light having an irradiation wavelength.
    Type: Grant
    Filed: December 28, 2017
    Date of Patent: December 22, 2020
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Kensuke Okawa, Seiki Hasunuma, Jun Azuma
  • 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
  • Publication number: 20200026207
    Abstract: An electrophotographic photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3) disposed directly or indirectly on the conductive substrate (2). The photosensitive layer (3) has a charge generating layer (3a) and a charge transport layer (3b) disposed in order from the conductive substrate (2). The charge generating layer (3a) contains a charge generating material. The charge transport layer (3b) contains a charge transport material, a binder resin, and a pigment that absorbs light having an irradiation wavelength. The binder resin includes a polyarylate resin including a repeating unit represented by general formula (1): In general formula (1), X and Y each represent, independently of one another, a divalent group represented by chemical formula (1-1).
    Type: Application
    Filed: December 28, 2017
    Publication date: January 23, 2020
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Kensuke OKAWA, Seiki HASUNUMA, 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
  • Publication number: 20180148538
    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: Application
    Filed: November 28, 2017
    Publication date: May 31, 2018
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Jun AZUMA, Kenji KITAGUCHI, Kensuke OKAWA, Seiki HASUNUMA, Tomofumi SHIMIZU
  • Publication number: 20180046099
    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: Application
    Filed: August 4, 2017
    Publication date: February 15, 2018
    Applicant: KYOCERA Document Solutions Inc.
    Inventors: Jun AZUMA, Kensuke OKAWA, Seiki HASUNUMA, Tomofumi SHIMIZU