Patents by Inventor Masakazu Tani

Masakazu Tani 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: 6926976
    Abstract: A magnetic recording medium comprising a non-magnetic support, at least one primer layer formed on one surface of the non-magnetic support, a magnetic layer formed on the primer layer, and a backcoat layer formed on the other surface of the non-magnetic support, wherein the magnetic layer has a thickness of 0.30 ?m or less and a centerline average surface roughness Ra of 3.2 nm or less, and (P1?P0) is 30 nm or less and (P1?P20) is 5 nm or less in which P0 is an averaged height of projections of the magnetic layer, and P1, P2, - - - and P20 are heights of the highest, the second highest, - - - and the 20th highest projections of the magnetic layer, respectively.
    Type: Grant
    Filed: December 3, 2003
    Date of Patent: August 9, 2005
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Masakazu Tani, Yoshiyuki Makita, Norihisa Yoshimoto, Kenichiro Yoshida
  • Patent number: 6921592
    Abstract: A magnetic recording medium comprising a non-magnetic support, at least one primer layer formed on one surface of the non-magnetic support, a magnetic layer formed on the primer layer, and a backcoat layer formed on the other surface of the non-magnetic support, wherein the magnetic layer has a thickness of 0.30 ?m or less and a centerline average surface roughness Ra of 3.2 nm or less, and (P1?P0) is 30 nm or less and (P1-P20) is 5 nm or less in which P0 is an averaged height of projections of the magnetic layer, and P1, P2, - - - and P20 are heights of the highest, the second highest, - - - and the 20th highest projections of the magnetic layer, respectively.
    Type: Grant
    Filed: December 3, 2003
    Date of Patent: July 26, 2005
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Masakazu Tani, Yoshiyuki Makita, Norihisa Yoshimoto, Kenichiro Yoshida
  • Publication number: 20040166373
    Abstract: A magnetic recording medium comprising a non-magnetic support, at least one primer layer formed on one surface of the non-magnetic support, a magnetic layer formed on the primer layer, and a backcoat layer formed on the other surface of the non-magnetic support, wherein the magnetic layer has a thickness of 0.30 &mgr;m or less and a centerline average surface roughness Ra of 3.2 nm or less, and (P1-P0) is 30 nm or less and (P1-P20) is 5 nm or less in which P0 is an averaged height of projections of the magnetic layer, and P1, P2, - - - and P20 are heights of the highest, the secondhighest, - - - and the 20th highest projections of the magnetic layer, respectively.
    Type: Application
    Filed: December 3, 2003
    Publication date: August 26, 2004
    Applicant: Hitachi Maxell Ltd.
    Inventors: Masakazu Tani, Yoshiyuki Makita, Norihisa Yoshimoto, Kenichiro Yoshida
  • Publication number: 20040166374
    Abstract: A magnetic recording medium comprising a non-magnetic support, at least one primer layer formed on one surface of the non-magnetic support, a magnetic layer formed on the primer layer, and a backcoat layer formed on the other surface of the non-magnetic support, wherein the magnetic layer has a thickness of 0.30 &mgr;m or less and a centerline average surface roughness Ra of 3.2 nm or less, and (P1-P0) is 30 nm or less and (P1-P20) is 5 nm or less in which P0 is an averaged height of projections of the magnetic layer, and P1, P2, - - - - and P20 are heights of the highest, the second highest, - - - and the 20th highest projections of the magnetic layer, respectively.
    Type: Application
    Filed: December 3, 2003
    Publication date: August 26, 2004
    Applicant: Hitachi Maxell Ltd.
    Inventors: Masakazu Tani, Yoshiyuki Makita, Norihisa Yoshimoto, Kenichiro Yoshida
  • Patent number: 6780531
    Abstract: A magnetic recording medium comprising a non-magnetic support, at least one primer layer formed on one surface of the non-magnetic support, a magnetic layer formed on the primer layer, and a backcoat layer formed on the other surface of the non-magnetic support, wherein the magnetic layer has a thickness of 0.30 &mgr;m or less and a centerline average surface roughness Ra of 3.2 nm or less, and (P1−P0) is 30 nm or less and (P1−P20) is 5 nm or less in which P0 is an averaged height of projections of the magnetic layer, and P1, P2, - - - and P20 are heights of the highest, the second highest, - - - and the 20th highest projections of the magnetic layer, respectively.
    Type: Grant
    Filed: October 31, 2001
    Date of Patent: August 24, 2004
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Masakazu Tani, Yoshiyuki Makita, Norihisa Yoshimoto, Kenichiro Yoshida
  • Publication number: 20040110036
    Abstract: A magnetic recording medium comprising a non-magnetic support, at least one primer layer formed on one surface of the non-magnetic support, a magnetic layer formed on the primer layer, and a backcoat layer formed on the other surface of the non-magnetic support, wherein the magnetic layer has a thickness of 0.30 &mgr;m or less and a centerline average surface roughness Ra of 3.2 nm or less, and (P1-P0) is 30 nm or less and (P1-P20) is 5 nm or less in which P0 is an averaged height of projections of the magnetic layer, and P1, P2, - - - and P20 are heights of the highest, the second highest, - - - and the 20th highest projections of the magnetic layer, respectively.
    Type: Application
    Filed: December 3, 2003
    Publication date: June 10, 2004
    Applicant: Hitachi Maxell Ltd.
    Inventors: Masakazu Tani, Yoshiyuki Makita, Norihisa Yoshimoto, Kenichiro Yoshida
  • Publication number: 20040091746
    Abstract: A magnetic tape which is run at a speed of 4 m/sec. or higher and has recording tracks with a width of 21 &mgr;m or less, and which comprises a non-magnetic support, at least one magnetic layer formed on one surface of the non-magnetic support, and a backcoat layer formed on the other surface of the non-magnetic support, wherein servo signals for controlling tracking are recorded on the magnetic layer or the backcoat layer, characterized in that the value of (&agr;/W)×(V/f) is 10 [s−1] or less, and/or the value of (&agr;/W) is 0.1 or less, wherein V [mm/sec.] is a tape-running speed is; &agr; [&mgr;m] is an amount of a weave with a cycle of f [mm] on one edge of the tape or the other edge thereof as the reference side for the running of the tape; and W [&mgr;m] is a width of the recording track. This magnetic tape can decrease PES and off-track and thus is excellent in servo tracking performance.
    Type: Application
    Filed: September 12, 2003
    Publication date: May 13, 2004
    Inventors: Akihiro Nakamura, Masakazu Tani, Kousuke Amano, Shinji Arakawa, Jyunichi Shimizu
  • Publication number: 20020164503
    Abstract: A magnetic recording medium comprising a non-magnetic support, at least one primer layer formed on one surface of the non-magnetic support, a magnetic layer formed on the primer layer, and a backcoat layer formed on the other surface of the non-magnetic support, wherein the magnetic layer has a thickness of 0.30 &mgr;m or less and a centerline average surface roughness Ra of 3.2 nm or less, and (P1-P0) is 30 nm or less and (P1-P20) is 5 nm or less in which P0 is an averaged height of projections of the magnetic layer, and P1, P2, . . . and P20 are heights of the highest, the second highest, . . . and the 20th highest projections of the magnetic layer, respectively.
    Type: Application
    Filed: October 31, 2001
    Publication date: November 7, 2002
    Inventors: Masakazu Tani, Yoshiyuki Makita, Norihisa Yoshimoto, Kenichiro Yoshida