Patents by Inventor Kiyoshi Kobata

Kiyoshi Kobata 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: 6037037
    Abstract: The present invention provides a thin multilayer magnetic recording medium having improved electromagnetic conversion property and durability, comprising coating layers of a lower non-magnetic layer and an upper magnetic layer. The non-magnetic layer of this magnetic recording medium comprises a non-magnetic needle body having an average major axis length of 0.25 to 1.0 .mu.m and an average minor axis length of 0.005 to 0.0151 .mu.m, a first binding resin having a glass transition temperature (Tg.sub.1) of 30 to 50.degree. C., and fatty acid ester. The content of the first binding resin is 15 to 30 wt % with respect to the non-magnetic needle body. The content of the fatty acid ester is 2 to 15 wt % with respect to the first binding resin. The magnetic layer having a dry thickness of 0.5 .mu.m or less comprises ferromagnetic powder and a second binding resin having a glass transition temperature (Tg.sub.2) of 40 to 70.degree. C. Tg.sub.1 is at least 5.degree. C. lower than Tg.sub.
    Type: Grant
    Filed: July 6, 1998
    Date of Patent: March 14, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kazunori Kubota, Fumio Echigo, Yukihiro Shimasaki, Takumi Haneda, Hirofumi Ito, Tetuo Fuchi, Kiyoshi Kobata
  • Patent number: 5811179
    Abstract: A magnetic recording medium including a non-magnetic polymeric support and a magnetic layer on the non-magnetic polymeric support. The magnetic layer is positioned to be in contact with a record/playback head and includes ferromagnetic powder, abrasive material and binder resin, with at least 40 parts by weight of the abrasive material per 100 parts by weight of the ferromagnetic powder. The ferromagnetic powder has a saturation magnetization .sigma.s of 80 emu/g or more and long axis length of 0.25 .mu.m or less.
    Type: Grant
    Filed: November 6, 1995
    Date of Patent: September 22, 1998
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kazunori Sakamoto, Hideo Hatanaka, Yasuhiro Ueyama, Kiyoshi Kobata, Kazunori Kubota, Hideki Okumura
  • Patent number: 5701225
    Abstract: A tape cassette has a pair of reels each including a reel hub, with each hub having an anchor groove defined in an outer peripheral surface thereof so as to extend in a lengthwise direction thereof. A generally elongated clamping piece is received within the anchor groove and has a predetermined width as measured circumferentially of the reel hub. A tape medium includes a length of magnetic recording tape having opposite ends, and a leader tape connected with each of the opposite ends of the length of magnetic recording tape by of a splicing tape of a predetermined length. One end of the leader tape remote from the length of magnetic recording tape is received within the reel hub and anchored to the reel hub with the clamping piece snapped into the anchor groove. The splicing tape is, when the tape medium is wound around the reel hub, positioned immediately radially outwardly of and encompassing the predetermined width of the clamping piece.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: December 23, 1997
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hideki Okumura, Kazunori Sakamoto, Kiyoshi Kobata, Kazunori Kubota
  • Patent number: 5355271
    Abstract: A sheet-shaped cleaner including a resilient film and nonwoven cloth consisting of synthetic fibers formed on one side of the film is disposed in opposition to a guide roller. A magnetic tape is sandwiched between the guide roller and the cleaner and with the magnetic surface of the magnetic tape being contacted by the nonwoven cloth of the cleaner. The film of the cleaner is wedged between locking portions of the cassette in order to cause the cleaner to bow in a direction away from the guide roller such that the nonwoven cloth of the cleaner is biased under a low force against the magnetic surface of the tape. Accordingly, foreign matter on the surface of the magnetic tape is removed.
    Type: Grant
    Filed: February 4, 1993
    Date of Patent: October 11, 1994
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masaru Watanabe, Tousaku Nishiyama, Tsumoru Ohata, Kiyoshi Kobata
  • Patent number: 4809105
    Abstract: A magnetic recording and/or reproducing device for recording information on a disc-like magnetic recording medium and/or reproducing the information from it, said magnetic recording and/or reproducing device having a pair of magnetic head members each composed of a magnetic head chip and a slide pad for slidably holding the disc-like magnetic recording medium at its both surfaces between the pair of magnetic head members under a predetermined contact pressure, wherein the slide pad is so disposed as to surround the magnetic head chip and the top portion of the magnetic head chip is so disposed as to protrude by a predetermined amount from a sliding contact surface between the slide pad and the disc-like magnetic recording medium.
    Type: Grant
    Filed: September 2, 1986
    Date of Patent: February 28, 1989
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kiyokazu Imanishi, Wataru Watanabe, Kiyoshi Kobata