Patents by Inventor Kunitsuna Sasaki

Kunitsuna Sasaki 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: 7556681
    Abstract: An ink-jet ink comprising at least water and an organic solvent having a boiling point of not less than 150° C. in an amount of not less than 50 weight % and not more than 80 weight % based on the total weight of the ink, wherein the organic solvent comprises an alkane diol represented by Formula (1) or (2) in an amount of not less than 45 weight % and not more than 70 weight % based on the total weight of the ink, and a glycol mono-ether represented by Formula (3) in an amount of not less than 5 weight % and not more than 15 weight % based on the total weight of the ink: Formula (1) R1—CH(OH)—CH(OH)—R2; Formula (2) R1—CH(OH)—CH2—CH(OH)—R2; Formula (3) CH3—O—R3—OH.
    Type: Grant
    Filed: April 30, 2008
    Date of Patent: July 7, 2009
    Assignee: Konica Minolta Holdings, Inc.
    Inventors: Kunitsuna Sasaki, Hirotaka Iijima
  • Publication number: 20080276833
    Abstract: An ink-jet ink comprising at least water and an organic solvent having a boiling point of not less than 150 ° C. in an amount of not less than 50 weight % and not more than 80 weight % based on the total weight of the ink, wherein the organic solvent comprises an alkane diol represented by Formula (1) or (2) in an amount of not less than 45 weight % and not more than 70 weight % based on the total weight of the ink, and a glycol mono-ether represented by Formula (3) in an amount of not less than 5 weight % and not more than 15 weight % based on the total weight of the ink: Formula (1) R1—CH(OH)—CH(OH)—R2; Formula (2) R1—CH(OH)—CH2—CH(OH)—R2; Formula (3) CH3—O—R3—OH.
    Type: Application
    Filed: April 30, 2008
    Publication date: November 13, 2008
    Applicant: KONICA MINOLTA HOLDINGS, INC.
    Inventors: Kunitsuna Sasaki, Hirotaka Iijima
  • Patent number: 5545462
    Abstract: Disclosed is a magnetic recording medium characterized in that plural magnetic layers are provided on a non-magnetic support, the uppermost layer of the magnetic layers contains a ferromagnetic metallic powder and/or a hexagonal system magnetic powder and a binder, at least one layer other than the uppermost layer contains Co-containing iron oxide and a binder, the film thickness of the uppermost layer is 0.5 .mu.m or less, and the surface of the uppermost layer of the magnetic layers has an R.sub.10z value of the magnetic layer defined below of 50 nm or less, by which electromagnetic conversion characteristics of a magnetic recording medium can be improved.
    Type: Grant
    Filed: July 8, 1994
    Date of Patent: August 13, 1996
    Assignees: Konica Corporation, Kabushiki Kaisha Toshiba
    Inventors: Narito Goto, Masanori Isshiki, Kunitsuna Sasaki, Nobuyuki Sekiguchi, Katsuyuki Takeda, Hideki Takahashi
  • Patent number: 5480713
    Abstract: A magnetic recording medium having an improved output property over the wide range of wavelength, by controlling the magnetic reluctance and saturated magnetic flux density of the outermost layer and at least one layer other than the outermost layer, as specified in the claims, is disclosed. A magnetic matal powder contained in the outermost layer has an average major axis length of not more than 250 nm and a ratio of the average major axis length divided by an average X-ray measured particle size is less than 12.
    Type: Grant
    Filed: September 1, 1993
    Date of Patent: January 2, 1996
    Assignee: Konica Corporation
    Inventors: Kunitsuna Sasaki, Narito Goto, Katsuyuki Takeda, Nobuyuki Sekiguchi, Hideki Takahashi, Ryosuki Isobe, Takahiro Mori
  • Patent number: 5478626
    Abstract: Disclosed are a magnetic recording medium which comprises a non-magnetic support, one or more coating layers provided on the non-magnetic support and an upper layer of the coating layers being a magnetic layer containing ferromagnetic metallic powder with the total thickness of the coating layers being 0.5 to 2.5 .mu.m, wherein the magnetic layer has a surface roughness Ra of 1.0 to 4.6 nm and a surface roughness R10z of 8.0 to 35.0 nm, which satisfy the relations of:Ra.ltoreq.-0.47t+0.5/t+3.8 andR10z.ltoreq.-1.50t+6.0/t+23.0where t is the total thickness of the coating layers in terms of .mu.m,and an aliphatic acid ester is contained in the surface portion of the magnetic layer in an amount of 5 to 50 mg/m.sup.2, and a process for preparing the same.
    Type: Grant
    Filed: September 30, 1994
    Date of Patent: December 26, 1995
    Assignees: Konica Corporation, TDK Corporation
    Inventors: Takahiro Mori, Kunitsuna Sasaki, Hisato Kato, Kazuyoshi Imai, Takahiro Hayashi
  • Patent number: 5460876
    Abstract: A magnetic recording medium is disclosed. The magnetic recording medium is produced by coating the following magnetic paints on a support in the order from the support,a lower layer magnetic paint having a creep strain of 20% to 1000% determined in the conditions with non-volatile content of the paint of 30 weight percent, a temperature 20.degree. C., and a loading weight of 1 Pascal, andan upper layer magnetic paint having a creep strain of 10% to 500% determined in the same conditions.
    Type: Grant
    Filed: August 2, 1993
    Date of Patent: October 24, 1995
    Assignee: Konica Corporation
    Inventors: Takafumi Yanagita, Kunitsuna Sasaki
  • Patent number: 5449527
    Abstract: Disclosed is a method of producing a magnetic recording medium which comprises a magnetic layer, comprising a step of kneading a magnetic coating solution containing a ferromagnetic powder and a binder for the magnetic layer under a load of substantial electric power consumption of 0.05 to 0.5 KW per Kg of the ferromagnetic powder in a kneader chamber having an atmospheric water content of not more than 1 g/m.sup.3.
    Type: Grant
    Filed: January 26, 1994
    Date of Patent: September 12, 1995
    Assignee: Konica Corporation
    Inventors: Seiichi Tobisawa, Ryosuke Isobe, Kunitsuna Sasaki
  • Patent number: 5324582
    Abstract: A magnetic recording medium having magnetic layers on the non-magnetic support. The surface of the non-magnetic support has more than 200 protrusions per mm of the measuring length having more than 0.01 .mu.m height, and protrusions having the height more than 0.30 .mu.m height less than 500 per 400 mm of the measuring length. The protrusions are on the surface of the magnetic layers provided or opposit side of the support or the both sides. These protrusions reduce the surface friction of the medium, resulting the better electro-magnetic properties and the longer life for repeated usages.
    Type: Grant
    Filed: May 10, 1993
    Date of Patent: June 28, 1994
    Assignee: Konica Corporation
    Inventors: Narito Goto, Katsuyuki Takeda, Kunitsuna Sasaki, Nobuyuki Sekiguchi
  • Patent number: 5320901
    Abstract: A magnetic recording tape of plural magnetic coating layers, which has excellent properties of both the electromagnetic conversion properties, particularly the chromatic output, and the corrosion resistance is disclosed. The top layer contains magnetic metal powder having the weight ratio of Al to Fe being 0.005 to 0.2, and the lower layer has the coercive force of not less than 650 Oe and not more than 1200 Oe.
    Type: Grant
    Filed: June 17, 1991
    Date of Patent: June 14, 1994
    Assignee: Konica Corporation
    Inventors: Narito Goto, Katsuyuki Takeda, Kunitsuna Sasaki, Nobuyuki Sekiguchi
  • Patent number: 5304416
    Abstract: A magnetic recording tape with plural magnetic layers, having both the electromagnetic conversion properties, particularly the chromatic output, and the corrosion resistance is disclosed.The top layer contains a magnetic metal powder having 0.2-1.5% of water when it is mixed into a magnetic paint and a layer other than the top layer has the coercive force of 500 to 12000 Oe.
    Type: Grant
    Filed: December 21, 1992
    Date of Patent: April 19, 1994
    Assignee: Konica Corporation
    Inventors: Narito Goto, Katsuyuki Takeda, Kunitsuna Sasaki, Nobuyuki Sekiguchi
  • Patent number: 5215833
    Abstract: A magnetic recording medium is disclosed. The medium comprises a non-magnetic support and, provided thereon, plural magnetic layers comprising the uppermost magnetic layer having a thickness of 1.5 .mu.m or less and lower magnetic layers, said plural magnetic layers containing a ferromagnetic powder, a binder and a lubricant, wherein a dynamic friction coefficient of the uppermost layer against a metal pin is 0.25 or less under the condition of a temperature of 20.degree. C. and a relative humidity of 60%, and 0.20 or less under the condition of a temperature of 40.degree. C. and a relative humidity of 20%.
    Type: Grant
    Filed: June 20, 1991
    Date of Patent: June 1, 1993
    Assignee: Konica Corporation
    Inventors: Narito Goto, Katsuyuki Takeda, Kunitsuna Sasaki, Nobuyuki Sekiguchi
  • Patent number: 5153079
    Abstract: A magnetic recording medium is disclosed which comprises a non-magnetic support and a magnetic layer comprising a ferromagnetic powder having a specific surface area of not less than 55 m.sup.2 /g and at least two kinds of resins each containing repetitive units having a polar group selected from the group consisting of a --SO.sub.3 M group, a --OSO.sub.3 M group, a --COOM group and a --PO(OM').sub.2 group, wherein M is a hydrogen atom or an alkali metal atom, and M' is a hydrogen atom, an alkali metal atom or an alkyl group, and the glass transition points of said two resins are different not less than 60.degree. C. from each other. The recording medium is improved in the dispersibility of the ferromagnetic powder in the magnetic layer and has a satisfactory surface smoothness, high electromagnetic conversion characteristics and a satisfactory running durability.
    Type: Grant
    Filed: December 6, 1991
    Date of Patent: October 6, 1992
    Assignee: Konica Corporation
    Inventors: Kunitsuna Sasaki, Kiyoshi Sawada, Ryosuke Isobe, Takahiro Mori, Yuki Ando
  • Patent number: 5151330
    Abstract: There is disclosed a magnetic recording medium having the excellent electromagnetic conversion properties and an improved Young's modulus of a magnetic layer, wherein the magnetic layer contains a binder comprising a polyurethane resin having a polycaprolactone structural unit and a vinyl chloride resin having --SO.sub.3 M, --COOM, --OSO.sub.3 M, ##STR1## wherein M represents hydrogen, lithium, sodium or potassium.
    Type: Grant
    Filed: November 13, 1990
    Date of Patent: September 29, 1992
    Assignee: Konica Corporation
    Inventors: Kenji Kumamoto, Kunitsuna Sasaki
  • Patent number: 5149585
    Abstract: A magnetic recording medium is disclosed, which is improved in electromagnetic conversion properties. The recording medium comprises a support, an uppermost magnetic mayer being provided on the support and one or more lower magnetic layers being provided between the support and the uppermost magnetic layer, in which the uppermost magnetic layer comprises a binder and a hexagonal magnetic powder and has a layer thickness of from 0.1 .mu.m to 1.0 .mu.m, and at least one of the lower magnetic layer comprises a binder having a anionic functional group and a magnetic powder, and has a coercive force of from 500 Oe to 1200 Oe, and the uppermost magnetic layer and the lower layer were formed on the support by wet-on-wet simultaneous multi-layer coating.
    Type: Grant
    Filed: July 8, 1991
    Date of Patent: September 22, 1992
    Assignee: Konica Corporation
    Inventors: Narito Goto, Katsuyuki Takeda, Kunitsuna Sasaki, Nobuyuki Sekiguchi
  • Patent number: 5094916
    Abstract: A magnetic recording medium is disclosed which has a magnetic layer comprising a ferromagnetic powder and a specific polyurethane resin as a binder. The polyurethane resin has a weight average molecular weight of not more than 30,000, a glass transition point of not higher than 0.degree. C. and a -SO.sub.3 M group, wherein M is a hydrogen atom or an alkali metal atom, in an amount of not less than 0.35% by weight in terms of sulfur atom. The recording medium is excellent in the dispersibility of the magnetic powder in the binder and has high running stability.
    Type: Grant
    Filed: December 18, 1990
    Date of Patent: March 10, 1992
    Assignee: Konica Corporation
    Inventors: Kunitsuna Sasaki, Kiyoshi Sawada, Ryosuke Isobe, Takahiro Mori, Yuki Ando
  • Patent number: 5061516
    Abstract: There is disclosed the method of preparing a magnetic recording medium having an improved running durability and the excellent electromagnetic conversion characteristics, wherein the magnetic paint for a magnetic layer is prepared by the steps of:kneading the ferromagnetic powder of 100 parts by weight, the first binder of 3 to 15 parts by weight, and a solvent of 10 to 60 parts by weight under a load of a power consumption of 0.05 to 0.5 KW per kg of the ferromagnetic powder to prepare a mixture thereof;kneading the second binder and the mixture under the load of the same power consumption to prepare a coating solution.
    Type: Grant
    Filed: January 3, 1991
    Date of Patent: October 29, 1991
    Assignee: Konica Corporation
    Inventors: Ryosuke Isobe, Kiyoshi Sawada, Kunitsuna Sasaki, Takahiro Mori, Yuki Ando
  • Patent number: 4731292
    Abstract: A magnetic recording medium is disclosed which comprises a support, and a magnetic layer comprising a specific binder resin, a fatty acid or a fatty acid ester and a magnetic particle. The binder resin comprises a monomer unit of vinyl chloride, a monomer unit having an alkalin metal salt of sulfonic acid or an alkaline salt of phosphoric acid and a monomer unit having an epoxy group. The magnetic recording medium is improved in a dispersibility of magnetic particles, a durability for still picture reproduction, a stability in running and in a S/N ratio of luminance.
    Type: Grant
    Filed: November 14, 1986
    Date of Patent: March 15, 1988
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Kunitsuna Sasaki, Yoshitaka Yasufuku, Toshiaki Shibue, Kazumasa Matsumoto
  • Patent number: RE36220
    Abstract: Disclosed are a magnetic recording medium which comprises a non-magnetic support, one or more coating layers provided on the non-magnetic support and an upper layer of the coating layers being a magnetic layer containing ferromagnetic metallic powder with the total thickness of the coating layers being 0.5 to 2.5 .mu.m, wherein the magnetic layer has a surface roughness Ra of 1.0 to 4.6 nm and a surface roughness R10z of 8.0 to 35.0 nm, which satisfy the relations of:Ra.ltoreq.-0.47t+0.5/t+3.8 andR10z.ltoreq.-1.50t+6.0/t+23.0where t is the total thickness of the coating layers in terms of .mu.m,and an aliphatic acid ester is contained in the surface portion of the magnetic layer in an amount of 5 to 50 mg/m.sup.2, and a process for preparing the same.
    Type: Grant
    Filed: March 8, 1996
    Date of Patent: June 1, 1999
    Assignees: Konica Corporation, TDK Corporation
    Inventors: Takahiro Mori, Kunitsuna Sasaki, Hisato Kato, Kazuyoshi Imai, Takahiro Hayashi