Patents by Inventor Tomoe Takamura

Tomoe Takamura 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: 6475680
    Abstract: A lithium secondary battery which is capable of terminating its operation safely with no accompanying rapid change in appearance, no gas generation, nor pressure change when any of an overcharge, overdischarge, and abnormal temperature rise occurs in the secondary battery itself. The lithium secondary battery includes a negative electrode, which is capable of absorbing and desorbing lithium, a positive electrode, which is capable of absorbing and desorbing lithium, and a non-aqueous electrolyte, wherein the non-aqueous electrolyte is solidified by a thermal reaction at a designated temperature.
    Type: Grant
    Filed: March 15, 1999
    Date of Patent: November 5, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Juichi Arai, Hideaki Katayama, Haruo Akahoshi, Tomoe Takamura, Takao Iwayanagi
  • Patent number: 6323163
    Abstract: The present invention is a fluorine-containing compound having i) a perfluoropolyoxyalkyl or -alkylene chain having an average molecular weight of 800 or more and ii) a cyclic or non-cyclic polyether atomic group. Its use as a low-scattering lubricant or surface modifier (water repellent) brings about an improvement in sliding durability of magnetic recording media.
    Type: Grant
    Filed: June 17, 1999
    Date of Patent: November 27, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Hiroshi Sasaki, Mitsuyoshi Shouji, Takayuki Nakakawaji, Tomoe Takamura, Mina Ishida, Yutaka Ito, Hiroyuki Matsumoto
  • Patent number: 6296917
    Abstract: A lubricating film is provided for a magnetic disk having a data region and a CSS region formed on its surface. The lubricating film ensures low stiction and good resistance to contact sliding in the data region and also ensures good CSS durability in the CSS region. Therefore, it is possible to provide a magnetic disk and a magnetic recording/reproducing device which do not cause problems with sliding between the magnetic head and the magnetic disk while the apparatus is running normally and even when the apparatus stops accidentally. The lubricating film formed in the data region of the magnetic disk is firmly fixed to the surface of the magnetic disk and is hardly liable to stiction. In addition, it is thick enough to ensure good durability even in the case of contact sliding.
    Type: Grant
    Filed: April 17, 1998
    Date of Patent: October 2, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Takayuki Nakakawaji, Mitsuyoshi Shouji, Tomoe Takamura, Hiroshi Sasaki, Shuji Imazeki, Yutaka Ito
  • Patent number: 5985403
    Abstract: A magnetic recording medium comprising a non-magnetic substrate and a magnetic layer and a protective layer which are formed on the non-magnetic substrate in that order, wherein a substance(s) as a single component or a plurality of components, which constitute a liquid continuously supplied to the surface of said protective layer, are adsorbed on or react with the surface of said protective layer to form a lubricating film having low frictional properties and low wearing-out properties. The present invention can realize negligible friction and wear resistance even in severe sliding at a very slightly kept-off or completely contacted state by continuous supply of a liquid lubricant prepared by adding a fluoro compound and an extreme pressure agent or an oiliness agent to a solvent to the surface of a disc, and can provide a magnetic recording reproducer having excellent sliding-resistant characteristics.
    Type: Grant
    Filed: March 18, 1994
    Date of Patent: November 16, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Takayuki Nakakawaji, Mitsuyoshi Shoji, Tomoe Takamura, Shuji Imazeki, Yutaka Ito, Hisashi Morooka, Yuko Murakami, Juichi Arai
  • Patent number: 4657685
    Abstract: A substantially water-free, emulsion type liquid lubricant for metal forming which comprises:(a) a lubricating oil,(b) at least one of phosphoric acid esters represented by the general formula: ##STR1## wherein R is alkyl, alkylalkenyl or aryl; n is an integer of 1 to 2, and (c) an emulsifying agent,an average particle size of the phosphoric acid ester being 0.3 to 120 .mu.m, can form a lubricating film having distinguished heat resistance and lubricating properties by virtue of the heat generated by deformation and friction during the metal forming only by wetting the surface of a metallic workpiece or a die or both with the lubricant and work effectively for preventing galling, and thus parts with a high reduction of area or parts of complicated shapes can be readily formed.A lubricating film having a lubricating effect equivalent to that of the conventional phasphate film can be simply obtained, greatly contributing to reduction in product cost.
    Type: Grant
    Filed: December 19, 1984
    Date of Patent: April 14, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Takao Uematsu, Shigeki Komatsuzaki, Fumio Nakano, Tomoe Takamura
  • Patent number: 4612127
    Abstract: A substantially water-free, liquid lubricant for metal forming, which comprises a lubricating oil, and at least one of linearly condensed phosphorus compounds represented by the following general formula (1):M.sub.m H.sub.n+2-m P.sub.n O.sub.3n+1 (1)wherein m is an integer of 0, 1, . . . , n+1, n is an integer of 2 to 6, and M is an alkali metal, and cyclically condensed phosphorus compounds represented by the following general formulae (2) and (3):(HPO.sub.3).sub.n (2)M.sub.x H.sub.y (PO.sub.3).sub.x+y (3)wherein n is an integer of 2 to 8, M is an alkali metal, and each of x and y is an integer of 1 or more, where x+y.ltoreq.
    Type: Grant
    Filed: September 26, 1984
    Date of Patent: September 16, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Takao Uematsu, Shigeki Komatsuzaki, Tomoe Takamura, Fumio Nakano, Toshikazu Narahara