Patents by Inventor Mamoru Kamigaki

Mamoru Kamigaki 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).

  • Publication number: 20020164502
    Abstract: A magnetic recording medium comprises:
    Type: Application
    Filed: February 4, 2002
    Publication date: November 7, 2002
    Inventors: Kazuyuki Hayashi, Keisuke Iwasaki, Mamoru Kamigaki, Hiroko Morii
  • Patent number: 6458453
    Abstract: A magnetic recording medium composed of a non-magnetic base film and a magnetic recording layer containing a binder resin, magnetic particles, and as a filler black composite hematite particles having an average diameter of 0.08 to 1.0 &mgr;m. The composite particles have cores of hematite particles which are surface coated with an organosilicon compound. A carbon black coating is formed on the organosilicon coating layer. In addition, the hematite core particles may have an oxide or hydroxide coating layer formed on the surface of the hematite core particle, between the organosilicon coating layer and the surface of the core particles. The magnetic recording medium has not only an excellent durability and a good electromagnetic performance, but also a low light transmittance, a small surface resistivity and an excellent surface smoothness.
    Type: Grant
    Filed: April 25, 2000
    Date of Patent: October 1, 2002
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Hiroko Morii, Mamoru Kamigaki, Seiji Ishitani
  • Publication number: 20010044036
    Abstract: A magnetic recording medium comprises:
    Type: Application
    Filed: March 14, 2001
    Publication date: November 22, 2001
    Inventors: Kazuyuki Hayashi, Mamoru Kamigaki, Hiroko Morii
  • Patent number: 6294242
    Abstract: A magnetic recording medium of the present invention comprises: a non-magnetic base film; and a magnetic recording layer comprising a binder resin and black magnetic acicular composite particles having an average particle diameter of 0.051 to 0.72 &mgr;m, comprising: magnetic acicular core particles; a coating formed on surface of said magnetic acicular core particles, comprising at least one organosilicon compound selected from the group consisting of: (1) organosilane compounds obtainable from alkoxysilane compounds, (2) polysiloxanes or modified polysiloxanes, and (3) fluoroalkyl organosilane compounds obtainable from fluoroalkylsilane compounds; and a carbon black coat formed on said coating layer comprising said organosilicon compound, in an amount of 0.5 to 10 parts by weight based on 100 parts by weight of said magnetic acicular particles.
    Type: Grant
    Filed: April 21, 2000
    Date of Patent: September 25, 2001
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Hiroko Morii, Mamoru Kamigaki, Yasuyuki Tanaka, Keisuke Iwasaki
  • Patent number: 6019834
    Abstract: A pigment of the present invention comprises:pigment particle as core particle;a lower coat formed on at least a part of surface of the pigment particle, comprising squaric acid, polyol having an anthraquinone skeleton represented by the general formula (I): ##STR1## wherein m is an integer of 0 to 4, n is an integer of 0 to 4 and m+n is an integer of 2 to 4,or a mixture of the squaric acid and the polyol having an anthraquinone skeleton represented by the general formula (I); andan upper coat formed on at least a part of surface of the obtained particle, comprising at least one alkylene glycol represented by the general formula (II):C.sub.q H.sub.2q (OH).sub.2 (II)wherein q is an integer of 2 to 10.Such pigment has excellent dispersion facility, dispersion homogeneity and dispersion stability, and is suitably used for not only organic solvent-type paints but also water-based paints.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: February 1, 2000
    Assignee: Toda Kogyo Corporation
    Inventors: Kazuyuki Hayashi, Mineko Ohsugi, Hiroko Morii, Mamoru Kamigaki
  • 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