Patents by Inventor Rieko Sakamoto

Rieko Sakamoto 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: 10025232
    Abstract: An intermediate transfer member for electrophotography comprising a substrate and a surface layer provided on the substrate. The surface layer comprises a binder resin and a perfluoropolyether. An extraction amount of the perfluoropolyether per 10 mm3 of the surface layer, is 0.10 mg to 5.00 mg, the extraction amount of the perfluoropolyether obtained by immersing the intermediate transfer member into a solvent that can dissolve the perfluoropolyether at 25° C. for 24 hours. A surface of the intermediate transfer member that is not subjected to first and second treatments, has a n-hexadecane contact angle of 55° or more. A surface of the intermediate transfer member that has been subjected to the first treatment, has a n-hexadecane contact angle of 40° or less. A surface of the intermediate transfer member that has been subjected to the second treatment, has a n-hexadecane contact angle of 50° or more.
    Type: Grant
    Filed: June 23, 2014
    Date of Patent: July 17, 2018
    Assignee: Canon Kabushiki Kaisha
    Inventors: Rieko Sakamoto, Kenji Onuma, Naoto Kameyama, Kimihiro Yoshimura, Akira Watanabe, Koichi Sato
  • Patent number: 9720353
    Abstract: The present invention relates to an electrophotographic intermediate transfer member that, even if an image is repeatedly and continuously transferred, can retain its transfer performance and can obtain an excellent image for a long time. The electrophotographic intermediate transfer member has a base layer and a surface layer, the surface layer has a matrix-domain structure in the cross section in the thickness direction, the matrix is formed of a binder resin, the domains contains a perfluoropolyether, and a microhardness of a surface of the electrophotographic intermediate transfer member measured by an ultramicro-hardness meter is 50 MPa or more.
    Type: Grant
    Filed: April 3, 2013
    Date of Patent: August 1, 2017
    Assignee: Canon Kabushiki Kaisha
    Inventors: Rieko Sakamoto, Koichi Sato, Kenji Onuma, Kimihiro Yoshimura, Naoto Kameyama, Yasushi Shimizu, Akira Watanabe
  • Patent number: 9250546
    Abstract: A member for electrophotography having a multilayer structure or a single-layer structure, including an outermost layer which satisfies the following A, B and C: A: the outermost layer has perfluoropolyether and a binder resin, and in the outermost layer, the ratio of the number of fluorine atoms to the number of carbon atoms is 0.10 or more and 0.40 or less; B: in a 19F-NMR spectrum of the outermost layer, the relaxation time T2 of a peak derived from CF2 moieties of perfluoropolyether is 13 milliseconds or more at 22° C.; and C: the total sum of the contents of CF3 moieties, CF2 moieties, and CF moieties in the binder resin is 5% by mass or less.
    Type: Grant
    Filed: June 24, 2014
    Date of Patent: February 2, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventors: Naoto Kameyama, Kenji Onuma, Rieko Sakamoto, Yasushi Shimizu, Koichi Sato, Kimihiro Yoshimura, Akira Watanabe, Maho Tanaka, Shigeki Takishita, Hiroshi Tominaga, Keiji Karube, Takenori Sueoka
  • Publication number: 20150323888
    Abstract: The present invention relates to an electrophotographic intermediate transfer member that, even if an image is repeatedly and continuously transferred, can retain its transfer performance and can obtain an excellent image for a long time. The electrophotographic intermediate transfer member has a base layer and a surface layer, the surface layer has a matrix-domain structure in the cross section in the thickness direction, the matrix is formed of a binder resin, the domains contains a perfluoropolyether, and a microhardness of a surface of the electrophotographic intermediate transfer member measured by an ultramicro-hardness meter is 50 MPa or more.
    Type: Application
    Filed: April 3, 2013
    Publication date: November 12, 2015
    Inventors: Rieko Sakamoto, Koichi Sato, Kenji Onuma, Kimihiro Yoshimura, Naoto Kameyama, Yasushi Shimizu, Akira Watanabe
  • Patent number: 8962133
    Abstract: An object of the present invention is to provide: an electrophotographic member which enhances image quality, prevents the lowering of a grade of an image even when images have been repeatedly output, and can remarkably enhance the stability of the grade of the image; an intermediate transfer member; and an image forming apparatus. The electrophotographic member includes a base layer and a surface layer, wherein the surface layer has a binder resin, perfluoropolymer fine particles, a fluorocarbon resin dispersing agent and a particular fluorine compound, wherein the perfluoropolymer fine particle has a fluorine compound carried on its surface.
    Type: Grant
    Filed: December 5, 2012
    Date of Patent: February 24, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventors: Koichi Sato, Naoto Kameyama, Kenji Onuma, Koichi Nakamura, Tadanobu Yoshikawa, Hiroshi Tominaga, Akira Watanabe, Yasushi Shimizu, Rieko Sakamoto
  • Publication number: 20140377695
    Abstract: A member for electrophotography having a multilayer structure or a single-layer structure, including an outermost layer which satisfies the following A, B and C: A: the outermost layer has perfluoropolyether and a binder resin, and in the outermost layer, the ratio of the number of fluorine atoms to the number of carbon atoms is 0.10 or more and 0.40 or less; B: in a 19F-NMR spectrum of the outermost layer, the relaxation time T2 of a peak derived from CF2 moieties of perfluoropolyether is 13 milliseconds or more at 22° C.; and C: the total sum of the contents of CF3 moieties, CF2 moieties, and CF moieties in the binder resin is 5% by mass or less.
    Type: Application
    Filed: June 24, 2014
    Publication date: December 25, 2014
    Inventors: Naoto Kameyama, Kenji Onuma, Rieko Sakamoto, Yasushi Shimizu, Koichi Sato, Kimihiro Yoshimura, Akira Watanabe, Maho Tanaka, Shigeki Takishita, Hiroshi Tominaga, Keiji Karube, Takenori Sueoka
  • Publication number: 20140377564
    Abstract: An intermediate transfer member for electrophotography comprising a substrate and a surface layer provided on the substrate. The surface layer comprises a binder resin and a perfluoropolyether. An extraction amount of the perfluoropolyether per 10 mm3 of the surface layer, is 0.10 mg or more and 5.00 mg or less, the extraction amount of the perfluoropolyether obtained by immersing the intermediate transfer member into a solvent that can dissolve the perfluoropolyether at 25 degrees in Celsius for 24 hours. A surface of the intermediate transfer member that is not subjected to first and second treatments, has a n-hexadecane contact angle of 55 degrees or more. A surface of the intermediate transfer member that has been subjected to the first treatment, has a n-hexadecane contact angle of 40 degrees or less. A surface of the intermediate transfer member that has been subjected to the second treatment, has a n-hexadecane contact angle of 50 degrees or more.
    Type: Application
    Filed: June 23, 2014
    Publication date: December 25, 2014
    Inventors: Rieko Sakamoto, Kenji Onuma, Naoto Kameyama, Kimihiro Yoshimura, Akira Watanabe, Koichi Sato