Patents by Inventor Mineko Sakoda

Mineko Sakoda 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).

  • Non-magnetic coated particles having a defined parameter .alpha. of not less than 0.5
    Patent number: 5882795
    Abstract: The disclosure describes a non-magnetic undercoating layer for a magnetic recording medium, coated on the surface of a non-magnetic substrate comprising:non-magnetic particles selected from the group consisting of particles (1) and (2):(1) coated acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles which are produced by adhering not less than 0.01 to 20 wt % (calculated as Al, SiO.sub.2 or Al and SiO.sub.2, and based on acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material) of an oxide or a hydroxide containing Al, Si or both Al and Si to the surfaces of acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material, and have a molecular weight-dependent parameter .alpha. represented by the following formula of not less than 0.5:As=K.sub.1 .multidot.M.sup..alpha.wherein M represents the number-average molecular weight of a binder resin, As represents the saturation adsorption of said binder resin, and K.sub.
    Type: Grant
    Filed: February 22, 1995
    Date of Patent: March 16, 1999
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Yasuyuki Tanaka, Minoru Ohsugi, Hiroko Morii, Mineko Sakoda, Norio Sugita, Masaaki Maekawa
  • Non-magnetic undercoating layer for magnetic recording medium, magnetic recording medium and non-magnetic particles
    Patent number: 5830557
    Abstract: The disclosure describes a non-magnetic undercoating layer for a magnetic recording medium, coated on the surface of a non-magnetic substrate comprising:non-magnetic particles selected from the group consisting of particles (1) and (2):(1) coated acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles which are produced by adhering not less than 0.01 to 20 wt % (calculated as Al, SiO.sub.2 or Al and SiO.sub.2, and based on acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material) of an oxide or a hydroxide containing Al, Si or both Al and Si to the surfaces of acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material, and have a molecular weight-dependent parameter .alpha. represented by the following formula of not less than 0.5:As=K.sub.1 .multidot.M.sup..alpha.wherein M represents the number-average molecular weight of a binder resin, As represents the saturation adsorption of said binder resin, and K.sub.
    Type: Grant
    Filed: February 22, 1995
    Date of Patent: November 3, 1998
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Yasuyuki Tanaka, Minoru Ohsugi, Hiroko Morii, Mineko Sakoda, Norio Sugita, Masaaki Maekawa
  • Modified particles
    Patent number: 5686012
    Abstract: The disclosure describes modified particles comprising inorganic particles as core particles, and at least one polysiloxane modified with at least one selected from the group consisting of polyethers, polyesters and aralkyls, which is coated on the surfaces of said core particles.
    Type: Grant
    Filed: September 1, 1995
    Date of Patent: November 11, 1997
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Hiroko Morii, Mineko Sakoda, Minoru Ohsugi, Mamoru Kamigaki
  • Non-magnetic undercoat layer for magnetic recording medium, magnetic recording medium and non-magnetic particles
    Patent number: 5604015
    Abstract: The disclosure describes a non-magnetic undercoating layer for a magnetic recording medium, coated on the surface of a non-magnetic substrate comprising:non-magnetic particles selected from the group consisting of particles (1) and (2):(1) coated acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles which are produced by adhering not less than 0.01 to 20 wt % (calculated as Al, SiO.sub.2 or Al and SiO.sub.2, and based on acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material) of an oxide or a hydroxide containing Al, Si or both Al and Si to the surfaces of acicular or spindle-shaped .alpha.-Fe.sub.2 O.sub.3 particles as a core material, and have a molecular weight-dependent parameter .alpha. represented by the following formula of not less than 0.5:As=K.sub.1 .multidot.M.sup..alpha.wherein M represents the number-average molecular weight of a binder resin, As represents the saturation adsorption of said binder resin, and K.sub.
    Type: Grant
    Filed: May 10, 1994
    Date of Patent: February 18, 1997
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Yasuyuki Tanaka, Minoru Ohsugi, Hiroko Morii, Mineko Sakoda, Norio Sugita, Masaaki Maekawa