Patents by Inventor Akira Nahara

Akira Nahara 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: 4639815
    Abstract: A magnetic recording medium comprising a non-magnetic support, a thin magnetic metal film on the support, and a protective layer on the thin magnetic film, the protective layer containing chromium and iron, the chromium being present in an amount of 6 to 40 wt % and the iron being the remainder. The protective layer may optionally contain up to 20% by weight nickel.
    Type: Grant
    Filed: April 27, 1984
    Date of Patent: January 27, 1987
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yoshihiro Arai, Akira Nahara
  • Patent number: 4626315
    Abstract: A process for forming an ultrafine pattern on a surface of a substrate, which includes steps of irradiating the substrate surface with radiation modulated according to information to be patterned, subjecting the substrate surface to deposition with a material reactive or not with the substrate, and subjecting the substrate surface to etching if a substrate-reactive material is used for deposition. By this process, an ultrafine pattern can easily be formed with a high accuracy.
    Type: Grant
    Filed: November 8, 1985
    Date of Patent: December 2, 1986
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tatsuji Kitamoto, Hiroshi Amari, Akira Nahara, Ryuji Shirahata, Yoshihiro Arai
  • Patent number: 4610903
    Abstract: A magneto-optical disk memory comprises a magneto-optical recording medium constituted by a flexible substrate, and a recording thin film overlaid on the substrate. The recording thin film is fabricated of an amorphous rare-earth transition metal alloy having the easy axis of magnetization normal to the film surface. The magneto-optical recording medium is sandwiched between two hard supporting disks.
    Type: Grant
    Filed: December 28, 1984
    Date of Patent: September 9, 1986
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Masaaki Nomura, Akira Nahara, Tatsuji Kitamoto
  • Patent number: 4609962
    Abstract: A metal thin film type magnetic recording medium having an improved weather resistance is disclosed, which comprises a non-magnetic support base having provided thereon a ferromagnetic metal thin film comprised of column-shaped clusters of ferromagnetic particle having longitudinal axes inclined to the surface plane of the support base and a layer of a chromium compound such as Cr and Cr.sub.2 O.sub.3 covering the surfaces of the column-shaped clusters.
    Type: Grant
    Filed: April 4, 1984
    Date of Patent: September 2, 1986
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yoshihiro Arai, Akira Nahara, Makoto Nagao, Kiyotaka Fukino
  • Patent number: 4565734
    Abstract: A magnetic recording medium comprises a non-magnetic substrate, a thin magnetic metal film layer overlaid on the substrate, a metallic oxide layer formed on the surface of the thin magnetic metal film layer, and a polymer film formed by plasma polymerization. The polymer film is overlaid on the metallic oxide layer to improve the corrosion resistance and durability of the magnetic recording medium.
    Type: Grant
    Filed: March 14, 1984
    Date of Patent: January 21, 1986
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yoshihiro Arai, Akira Nahara, Kiyotaka Fukino
  • Patent number: 4557944
    Abstract: A nonbinder type of magnetic recording medium is disclosed. The binder is comprised of a non-magnetic support having thereon, in sequence, a thin magnetic metal film laminated using the evaporation technique and a protecting film, with the thin magnetic metal film converted in its surface part alone to a metal oxide layer by being oxidized with oxygen plasma, to a metal nitride layer by being nitrided with nitrogen plasma or to a glow discharge-processed layer. The protecting film includes a high molecular weight compound, a higher fatty acid, a fatty acid ester or a combination thereof, laminated on the metal oxide layer, the metal nitride layer or the glow discharge-processed layer.
    Type: Grant
    Filed: January 18, 1985
    Date of Patent: December 10, 1985
    Assignee: Fuji Photo Film Company Limited
    Inventors: Yoshihiro Arai, Akira Nahara
  • Patent number: 4551778
    Abstract: A magnetic recording medium and a process for producing it is disclosed. The medium is comprised of a non-magnetic flexible support base and a magnetic layer formed on a surface of the support base. The magnetic layer is preferably in the form of a thin, ferromagnetic metal film formed by vapor deposition. An overcoat layer of a fluorine-containing organic material is formed directly on the magnetic layer. The fluorine content of the overcoat layer continuously and gradually decreases in the direction toward the magnetic layer. Accordingly, high fluorine content near the surface of the overcoat layer provides improved smoothness near the surface whereas the lower fluorine content near the interface of the overcoat with the magnetic layer allows for strong adhesion between the overcoat and the underlying magnetic layer substrate.
    Type: Grant
    Filed: August 2, 1983
    Date of Patent: November 5, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yoshihiro Arai, Akira Nahara
  • Patent number: 4543275
    Abstract: A process for forming a vapor-deposited thin layer of organic material is disclosed. The process involves placing organic material on a support base within a vacuum chamber and providing a heat source in the vicinity of the organic material. A second support base is then provided within the vacuum chamber and heat is applied to the organic material at a temperature which causes the organic material to form vapors. The vapors are vapor-deposited on the second support base forming the thin layer of organic material. It is generally desirable to move both of the support bases during the vapor deposition process allowing the formation of a continuous uniform thin layer of organic material.
    Type: Grant
    Filed: September 16, 1983
    Date of Patent: September 24, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Goro Akashi, Akira Nahara, Yoshihiro Arai
  • Patent number: 4536443
    Abstract: A magnetic recording medium comprises a non-magnetic substrate and at least one layer of obliquely deposited magnetic crystals which contains, as a main constituent, Co or a Co--Ni based alloy containing Cr in an amount within the range of 2 to 8 atom % and has a density of 5.0 g/cm.sup.3 or more, said layer being formed on said non-magnetic substrate.
    Type: Grant
    Filed: September 26, 1983
    Date of Patent: August 20, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Makoto Nagao, Akira Nahara
  • Patent number: 4521481
    Abstract: A magnetic recording medium comprises a non-magnetic substrate and at least one layer of obliquely deposited magnetic crystals which contains, as a main constituent, a Co-Ni based alloy containing Cr in an amount within the range of 2 to 8 atom % and which is obliquely deposited on the non-magnetic substrate in such a manner that the minimum angle of incidence of a vapor stream of a magnetic material with respect to the line normal to the non-magnetic substrate is 45.degree. or less.
    Type: Grant
    Filed: September 26, 1983
    Date of Patent: June 4, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Makoto Nagao, Akira Nahara
  • Patent number: 4521482
    Abstract: A magnetic recording medium having a layer of an organic polymer formed on an oblique vapor deposited magnetic metal film is disclosed. A layer of a higher aliphatic acid and/or an ester thereof is also formed on said polymer layer.
    Type: Grant
    Filed: December 19, 1983
    Date of Patent: June 4, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yoshihiro Arai, Akira Nahara
  • Patent number: 4511635
    Abstract: A magnetic recording medium comprises a non-magnetic high-molecular film and at least one magnetic layer containing Co, Ni, Cr and oxygen and formed on the non-magnetic high-molecular film by an oblique incidence vacuum deposition method. The Cr content is within the range of 2 to 8 atom %, the content of oxygen is within the range of 5 to 25 atom %, and the ratio of the number of oxygen atoms to the number of Cr atoms is within the range of 2:1 to 10:1.
    Type: Grant
    Filed: September 30, 1983
    Date of Patent: April 16, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Makoto Nagao, Akira Nahara
  • Patent number: 4501225
    Abstract: A magnetic metal deposition material contained in a hearth is heated and evaporated in a vacuum to form a flow of vapor, which is then ionized and converged toward a predetermined deposition surface of a flexible substrate. The flexible substrate is moved obliquely downwardly along a convex course by sliding contact with the curved surface of a fixed curved guiding body between a pair of guide rollers located at different heights above the hearth. The fixed curved guiding body communicates with a coolant source for cooling the substrate moving in contact therewith and may be provided with oscillators. Thus a thin film of the magnetic metal is deposited on the convex surface of the substrate.
    Type: Grant
    Filed: March 15, 1984
    Date of Patent: February 26, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Makoto Nagao, Akira Nahara, Goro Akashi
  • Patent number: 4495242
    Abstract: A nonbinder type of magnetic recording medium is disclosed. The binder is comprised of a non-magnetic support having thereon, in sequence, a thin magnetic metal film laminated using the evaporation technique and a protecting film, with the thin magnetic metal film converted in its surface part alone to a metal oxide layer by being oxidized with oxygen plasma, to a metal nitride layer by being nitrided with nitrogen plasma or to a glow discharge-processed layer. The protecting film includes a high molecular weight compound, a higher fatty acid, a fatty acid ester or a combination thereof, laminated on the metal oxide layer, the metal nitride layer or the glow discharge-processed layer.
    Type: Grant
    Filed: April 1, 1982
    Date of Patent: January 22, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yoshihiro Arai, Akira Nahara
  • Patent number: 4476000
    Abstract: A method of making a magnetic film target for use in sputtering characterized by forming a film of a magnetic material on a substrate by ion-plating a raw magnetic material thereon. The raw magnetic material is either identical with the magnetic film material or an ingredient or ingredients for constituting it. In the latter case, one or more metallic ingredients are simultaneously ion-plated in the same system to form a magnetic alloy or compound film on the substrate. To prepare a magnetic alloy target in which the composition changes in the thickness direction, the ion plating ratio of respective metallic ingredients is changed with time.
    Type: Grant
    Filed: October 21, 1981
    Date of Patent: October 9, 1984
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Makoto Nagao, Akira Nahara, Yoshihiro Arai
  • Patent number: 4451501
    Abstract: A magnetic metal deposition material contained in a hearth is heated and evaporated in a vacuum to form a flow of vapor, which is then ionized and converged toward a predetermined deposition surface of a flexible substrate. The flexible substrate is moved obliquely downwardly along a convex course by sliding contact with the curved surface a fixed curved guiding body between a pair of guide rollers located at different heights above the hearth. The fixed curved guiding body communicates with a coolant source for cooling the substrate moving in contact therewith and may be provided with oscillators. Thus a thin film of the magnetic metal is deposited on the convex surface of the substrate.
    Type: Grant
    Filed: April 15, 1982
    Date of Patent: May 29, 1984
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Makoto Nagao, Akira Nahara, Goro Akashi
  • Patent number: 4419404
    Abstract: A magnetic recording medium and a process for producing it is disclosed. The medium is comprised of a non-magnetic flexible support base and a magnetic layer formed on a surface of the support base. The magnetic layer is preferably in the form of a thin, ferromagnetic metal film formed by vapor deposition. An overcoat layer of a fluorine-containing organic material is formed directly on the magnetic layer. The fluorine content of the overcoat layer continuously and gradually decreases in the direction toward the magnetic layer. Accordingly, high fluorine content near the surface of the overcoat layer provides improved smoothness near the surface whereas the lower fluorine content near the interface of the overcoat with the magnetic layer allows for strong adhesion between the overcoat and the underlying magnetic layer substrate.
    Type: Grant
    Filed: February 16, 1982
    Date of Patent: December 6, 1983
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yoshihiro Arai, Akira Nahara
  • Patent number: 4367257
    Abstract: A magnetic recording medium having a thin magnetic amorphous rare earth metal-transition metal alloy film is disclosed, the amorphous alloy film having an axis of easy magnetization in a direction substantially vertical to the film surface and containing a crystalline phase in the amorphous phase. The magnetic recording medium exhibits high coercive force over a wide compositional range.
    Type: Grant
    Filed: April 16, 1981
    Date of Patent: January 4, 1983
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yoshihiro Arai, Makoto Nagao, Akira Nahara
  • Patent number: 4317123
    Abstract: A thermal recording material possessing high sensitivity which comprises a support having thereon in sequence a subbing layer, a recording layer and optionally, a protecting layer in which the subbing layer contains a composition comprising (A) 100 parts by weight of chlorinated polyolefin having a chlorine content of about 30% by weight or more and (B) 1 part to 100 parts by weight of aminoalkylalkoxysilane compound represented by the following general formula (I): ##STR1## wherein R.sup.1 represents an amino group or a H.sub.2 N--R.sup.5 --NH-- group; R.sup.2 and R.sup.5 each represents a polymethylene group having 1 to 2 carbon atoms or a straight or branched chain alkylene (alkanediyl) group having 3 to 5 carbon atoms, and may be the same or different; R.sup.3 represents a straight or branched chain alkyl group having 1 to 5 carbon atoms; m represents 2 or 3; R.sup.4 represents a straight or branched chain alkyl group having 1 to 5 carbon atoms or an R.sup.1 --R.sup.
    Type: Grant
    Filed: October 25, 1979
    Date of Patent: February 23, 1982
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tomizo Namiki, Osamu Seshimoto, Fumiaki Shinozaki, Akira Nahara, Tomoaki Ikeda
  • Patent number: 4286045
    Abstract: An image forming material comprising a support having thereon a layer composed of a Ge-S composition or a Ge-S-X composition wherein X represents at least one element selected from the group consisting of Al, Si, Mg, Ti, V, Mn, Co, Ni, Sn, Zn, Pd, In, Se, Te, Fe, I, P and O which undergoes a structural change capable of being detected optically, electrically or chemically upon exposure imagewise to light wherein the Ge-S or Ge-S-X composition layer has a thickness of at least about 300 A and contains therein at least one element selected from the group consisting of Ag, Cu and Pb in an amount of more than 2 atoms of Ag, Cu and/or Pb based on 100 atoms of the Ge-S composition or the Ge-S-X composition.
    Type: Grant
    Filed: November 15, 1979
    Date of Patent: August 25, 1981
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Akira Nahara, Yoshihiro Ono, Tomizo Namiki, Shigeo Harada, Yuzo Mizobuchi, Tomoaki Ikeda