Patents by Inventor Kuniharu Fujiki

Kuniharu Fujiki 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: 6861126
    Abstract: On a polymeric substrate 1, there is formed with a single magnetic layer 2 containing a ferromagnetic metal and oxygen. The magnetic layer 2 is divided into three regions equally in the depth direction from the polymeric substrate 1 to the surface of the magnetic layer 2, wherein the three regions are defined as a first region 21, a second region 22 and a third region 23 respectively in accordance with a process of forming the magnetic layer 2. With defining that a maximum value of oxygen concentration in the first region 21 is “Max 1”, a minimum value of oxygen concentration in the second region 22 is “Min 2”, and a maximum value of oxygen concentration in the third region 23 is “Max 3” respectively, these values “Max 1”, “Min 2” and “Max 3” have relations of “Min 2”<“Max 1” and “Min 2”?“Max 3”?“Max 1”.
    Type: Grant
    Filed: February 6, 2003
    Date of Patent: March 1, 2005
    Assignee: JVC Victor Company of Japan, Ltd.
    Inventor: Kuniharu Fujiki
  • Publication number: 20030152812
    Abstract: On a polymeric substrate 1, there is formed with a single magnetic layer 2 containing a ferromagnetic metal and oxygen. The magnetic layer 2 is divided into three regions equally in the depth direction from the polymeric substrate 1 to the surface of the magnetic layer 2, wherein the three regions are defined as a first region 21, a second region 22 and a third region 23 respectively in accordance with a process of forming the magnetic layer 2. With defining that a maximum value of oxygen concentration in the first region 21 is “Max 1”, a minimum value of oxygen concentration in the second region 22 is “Min 2”, and a maximum value of oxygen concentration in the third region 23 is “Max 3” respectively, these values “Max 1”, “Min 2” and “Max 3” have relations of “Min 2”<“Max 1” and “Min 2”≦“Max 3”≦“Max 1”.
    Type: Application
    Filed: February 6, 2003
    Publication date: August 14, 2003
    Applicant: VICTOR COMPANY OFJAPAN, LIMITED
    Inventor: Kuniharu Fujiki
  • Patent number: 6093486
    Abstract: Magnetic paint for producing a magnetic recording medium, the magnetic paint comprises at least ferromagnetic powder, binder, .alpha.-Fe.sub.2 O.sub.3 powder, and alumina powder. A relationship between an additive amount (A) of the .alpha.-Fe.sub.2 O.sub.3 powder and an additive amount (B) of the alumina powder is 5.ltoreq.(A+B).ltoreq.25 weight-parts referred to 100 weight-parts of the ferromagnetic powder and 1.ltoreq.A/B.ltoreq.9. The binder comprises polyurethane resin containing metal base sulfonic acid and tertiary amine as major ingredients.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: July 25, 2000
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Kazuhiro Takeda, Kuniharu Fujiki
  • Patent number: 4759980
    Abstract: A magnetic recording medium comprising a non-magnetic support and a magnetic recording layer formed on at least one side of the support. The layer is made of a composition which comprises two types of polyesters as a binder. The polyesters have glass transition temperatures of not lower than 50.degree. C. and not higher than 10.degree. C., respectively.
    Type: Grant
    Filed: February 12, 1987
    Date of Patent: July 26, 1988
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Ikuo Matsumoto, Kuniharu Fujiki, Satoshi Sekiya
  • Patent number: 4708906
    Abstract: A magnetic recording medium comprising a non-magnetic support and a magnetic recording layer formed on the support through an undercoat layer. The undercoat layer is made of a combination of a thermosetting polyurethane resin, carbon black and an ammonium salt of a phosphoric ester of the following formula ##STR1## in which each R.sub.1, each R.sub.2 and R.sub.3 independently represent an alkyl group having from 1 to 18 carbon atoms, alkoxy group having from 1 to 4 carbon atoms, an or phenyl group. Preferably, in the formula, each R.sub.1 represents CH.sub.3, each R.sub.2 represents an alkyl group having from 1 to 14 carbon atoms, and R.sub.3 represents --OCH.sub.3 or a phenyl radical. The undercoat layer may further comprise a thermosetting polyester resin so as to improve adhesiveness.
    Type: Grant
    Filed: April 17, 1985
    Date of Patent: November 24, 1987
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Satoshi Sekiya, Ikuo Matsumoto, Kuniharu Fujiki
  • Patent number: 4699817
    Abstract: Magnetic recording mediums comprising a nonmagnetic substrate and a magnetic recording layer formed on at least one side of the substrate. The magnetic recording layer is made of a composition which comprises magnetic particles dispersed in a combination of polyester and polyurethane resins and oleic acid, so that the magnetic medium is significantly improved in durability and lubricating property.
    Type: Grant
    Filed: April 28, 1986
    Date of Patent: October 13, 1987
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Kuniharu Fujiki, Ikuo Matsumoto
  • Patent number: 4671995
    Abstract: A magnetic recording medium which comprises a non-magnetic support, and a magnetic layer formed on the support through an undercoat layer is described. The undercoat layer is made of a cured product of a mixture of a thermosetting polyurethane resin and a thermosetting polyester used in an amount of not greater than 10 wt % of the polyurethane resin. The undercoat layer further comprises a phosphate ester.
    Type: Grant
    Filed: February 11, 1985
    Date of Patent: June 9, 1987
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Satoshi Sekiya, Ikuo Matsumoto, Kuniharu Fujiki
  • Patent number: 4634627
    Abstract: A magnetic recording medium comprising a nonmagnetic support, and a magnetic recording layer formed on said support. The magnetic recording layer comprises a magnetic powder and an abrasive powder dispersed in a resin binder. The abrasive powder has a coating of an isocyanate compound having at least two isocyanate groups in one molecule thereof and is used in an amount of from 0.5 to 20 parts by weight per 100 parts by weight of the magnetic powder.
    Type: Grant
    Filed: November 8, 1985
    Date of Patent: January 6, 1987
    Assignee: Victor Company of Japan, Limited
    Inventors: Kuniharu Fujiki, Hiroshi Togashi
  • Patent number: 4521480
    Abstract: A magnetic recording medium of the high recording density type is disclosed, which comprises a support, and a magnetic recording layer formed on at least one side of the support. The magnetic recording layer is made of a dispersion, in a binder, of magnetic alloy particles and TiO particles in an amount of from 0.1 to 20 wt % of said magnetic alloy particles.
    Type: Grant
    Filed: August 9, 1983
    Date of Patent: June 4, 1985
    Assignee: Victor Company of Japan, Limited
    Inventor: Kuniharu Fujiki
  • Patent number: 4501800
    Abstract: Magnetic recording media are described which comprise a support having a magnetic recording layer thereon. The magnetic recording layer is made of a dispersion of magnetic particles in a binder and a specific type of organosilicone. The organosilicone is represented by the general formula ##STR1## in which R represents a monovalent saturated or unsaturated hydrocarbon having 7 to 21 carbon atoms, R.sub.1, R.sub.2 and R.sub.3 independently represent a methyl or RCOO group, R.sub.4 is a saturated hydrocarbon group having 1 to 20 carbon atoms, and k, l, m and n are independently an integer provided that 1<K, 1.ltoreq.l<200, 1.ltoreq.m<200, 0.ltoreq.n<300, and l+m+n.ltoreq.500.
    Type: Grant
    Filed: July 27, 1983
    Date of Patent: February 26, 1985
    Assignee: Victor Company of Japan, Limited
    Inventors: Kuniharu Fujiki, Shigeru Hashimoto
  • Patent number: 4469750
    Abstract: Magnetic recording media are described which comprise a support having a magnetic recording layer thereon. The magnetic recording layer is made of a dispersion of magnetic particles in a binder and a specific type of fatty acid-modified, fluorinated organosilicone. The organosilicone is represented by the general formula ##STR1## in which R.sub.1 represents a monovalent saturated or unsaturated hydrocarbon having 7 to 21 carbon atoms, R.sub.2 represents a methyl or phenyl group, each R.sub.3 represents a OCOR.sub.1 in which R.sub.1 has the same meaning as defined above, Y represents --CF.sub.3 or --(CF.sub.2)--.sub.k W in which k is an integer of from 1 to 8, and W is hydrogen or fluorine, and l, m and n are independently an integer provided that 0.ltoreq.l<200, 1.ltoreq.m<100, 1.ltoreq.n<100, and l+m+n.ltoreq.300.
    Type: Grant
    Filed: July 27, 1983
    Date of Patent: September 4, 1984
    Assignee: Victor Company of Japan, Limited
    Inventors: Kuniharu Fujiki, Yukio Matsumoto, Hiroshi Yoshida
  • Patent number: 4383000
    Abstract: A magnetic recording medium which comprises a support and a magnetic layer formed on the support which is comprised of a magnetic powder dispersed in a binder and containing a lubricant. The lubricant contains at least as ester of a linear aliphatic acid having 14-18 carbon atoms and an alcohol of the general formula, (CH.sub.3).sub.2 CH--(CH.sub.2).sub.n --OH in which n is an integer of from 1 to 5. Preferably, an ester of a linear aliphatic acid having 14-18 carbon atoms and an alcohol of the formula, CH.sub.3 --(CH.sub.2).sub.m --CH.sub.2 OH, in which m is an integer of from 2 to 4 is contained.
    Type: Grant
    Filed: January 7, 1981
    Date of Patent: May 10, 1983
    Assignee: Victor Company of Japan, Limited
    Inventor: Kuniharu Fujiki
  • Patent number: 4383001
    Abstract: A magnetic recording medium which comprises a support and a magnetic layer formed on the support and comprised of a magnetic powder dispersed in a binder and also of a lubricant. The lubricant contains at least an ester of a linear aliphatic acid having 14-18 carbon atoms and an alcohol of the general formula, ##STR1## in which R and R' are independently a linear alkyl group having 5-10 carbon atoms. Preferably, an ester of a linear aliphatic acid having 14-18 carbon atoms and a linear or branched alcohol having 4-8 carbon atoms are also contained in the magnetic recording medium.
    Type: Grant
    Filed: January 7, 1981
    Date of Patent: May 10, 1983
    Assignee: Victor Company of Japan, Limited
    Inventor: Kuniharu Fujiki