With Magnetic Bias Patents (Class 360/17)
  • Publication number: 20030156339
    Abstract: Disclosed is a magnetic transfer apparatus including a holder for accommodating a slave medium subjected to transfer of information and master carriers bearing an information to be transferred which are to be kept in the state of being sucked to pressure-reducing suction parts of an inner surface of an inner space of the holder for mutual close contact of surfaces of the slave medium and the master carriers, a vacuum suction unit for providing a vacuum condition of the inner space, and a magnetic field application unit for applying a transfer magnetic field to the holder, wherein at the time of performing magnetic transfer, pressure of the inner space of the holder by the vacuum suction unit is set to be higher by 1-50 kPa than suction pressure of the pressure-reducing suction parts, whereby before mutual contact of the slave medium and the master carriers, a suction state of the master carriers is kept as it is, thus preventing the master carriers or the slave medium from being undesirably separated or misal
    Type: Application
    Filed: February 14, 2003
    Publication date: August 21, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventor: Akito Kamatani
  • Patent number: 6606209
    Abstract: A master information carrier comprises a substrate whose surface has an embossed pattern corresponding to an information signal. At least a surface of the protruding portion of the embossed pattern is made of a ferromagnetic material. A method for writing an information signal into a sheet or disk magnetic record medium with a ferromagnetic thin film or coating is performed by putting the surface of the magnetic record medium into contact with the master information carrier so as to write a magnetized pattern corresponding to the embossed pattern of the master information carrier into the magnetic record medium.
    Type: Grant
    Filed: March 26, 2002
    Date of Patent: August 12, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuaki Ishida, Ryuji Sugita, Kiyokazu Tohma, Keizou Miyata, Hiroshi Ryonai
  • Patent number: 6606208
    Abstract: A master information carrier comprises a substrate whose surface has an embossed pattern corresponding to an information signal. At least a surface of the protruding portion of the embossed pattern is made of a ferromagnetic material. A method for writing an information signal into a sheet or disk magnetic record medium with a ferromagnetic thin film or coating is performed by putting the surface of the magnetic record medium into contact with the master information carrier so as to write a magnetized pattern corresponding to the embossed pattern of the master information carrier into the magnetic record medium.
    Type: Grant
    Filed: February 26, 2002
    Date of Patent: August 12, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuaki Ishida, Ryuji Sugita, Kiyokazu Tohma, Kazunari Yoshimoto, Keizou Miyata
  • Publication number: 20030142427
    Abstract: The master information recording apparatus 100 includes a master information carrier, a master information carrier facing member, and a magnetic field applying member. A ferromagnetic thin film pattern formed on the surface of the master information carrier includes not less than two kinds of different patterns each having a different pattern angle showing an angle with respect to the direction of the relative movement between a magnetic head and a rotating magnetic recording medium. The magnetic field applying unit applies a magnetic field along the direction, which is perpendicular to the direction shown by an angle that is smaller than the pattern angle of the maximum pattern and larger than the minimum pattern angle of the pattern among the not less than two kinds of patterns.
    Type: Application
    Filed: January 30, 2003
    Publication date: July 31, 2003
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yasuaki Ban, Keizo Miyata, Taizou Hamada, Kouji Taniguchi, Masaya Sakaguchi
  • Publication number: 20030133211
    Abstract: A system and method for servo formatting magnetic media using contact magnetic printing is disclosed. The apparatus includes a dipole magnet that supplies a magnetic field to a magnetic media, a holder for holding the magnetic media, a set of stampers with servo patterns and a press for pressing the magnetic media firmly against the stampers while the magnetic media and stampers are being exposed to a magnetic field and a set of elastomer pads to distribute and equalize the force of the press on the magnetic media. Servo formatting, using the contact magnetic printing apparatus, is done by first positioning the magnetic media against the stampers having servo patterns on them. The magnetic media/stampers stack are then loaded and aligned in a system for contact magnetic printing, applying a force on the magnetic media and stamper so that the two are in firm contact with each other.
    Type: Application
    Filed: September 30, 2002
    Publication date: July 17, 2003
    Inventors: Li-Ping Wang, Andrew George Prax, David Shaio-Min Kuo
  • Patent number: 6590727
    Abstract: A master information carrier comprises a substrate whose surface has an embossed pattern corresponding to an information signal. At least a surface of the protruding portion of the embossed pattern is made of a ferromagnetic material. A method for writing an information signal into a sheet or disk magnetic record medium with a ferromagnetic thin film or coating is performed by putting the surface of the magnetic record medium into contact with the master information carrier so as to write a magnetized pattern corresponding to the embossed pattern of the master information carrier into the magnetic record medium.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: July 8, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuaki Ishida, Ryuji Sugita, Kiyokazu Tohma, Kazunari Yoshimoto, Keizou Miyata
  • Publication number: 20030123169
    Abstract: A master medium for magnetic transfer includes a substrate having a concave portion formed in its surface corresponding to a pattern of recorded information to be transferred; a first perpendicular ferromagnetic layer deposited in the concave portion; and a second perpendicular ferromagnetic layer layered on the substrate surface and the first perpendicular ferromagnetic layer surface. The substrate surface and the first perpendicular ferromagnetic layer surface are flattened to form a single flat surface. In the master medium for magnetic transfer, a magnetic field change in a direction parallel to the substrate surface at a magnetization boundary of the first perpendicular ferromagnetic layer is steep. Since the influence of the change of an external magnetic field is reduced, it is possible to perform accurate transfer from the master medium for magnetic transfer to a slave medium for magnetic recording.
    Type: Application
    Filed: March 20, 2002
    Publication date: July 3, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Shingo Hamaguchi, Sumio Kuroda, Kazuyuki Ozaki, Ken Tamanoi, Koji Matsumoto
  • Publication number: 20030123170
    Abstract: A master information carrier includes a high-level region and a low-level region that are formed on a non-magnetic base. The high-level region includes a ferromagnetic thin film pattern that corresponds to preformat information signals. The master information carrier is brought into close contact with a magnetic disk by exhausting a gas from a hole of the magnetic disk to generate negative pressure in a space between the low-level region and the magnetic disk. In this case, to prevent deformation of the central portion of the master information carrier, an inner edge of the high-level region in the radial direction is extended to the vicinity of a hole edge of the magnetic disk so that a portion of the high-level region comes into contact with the vicinity of the hole edge. This configuration can improve the close contact between the master information carrier and the magnetic disk, thus achieving higher reliability of magnetic transfer recording.
    Type: Application
    Filed: December 27, 2002
    Publication date: July 3, 2003
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Keizo Miyata, Hideyuki Hashi, Tatsuaki Ishida
  • Patent number: 6587289
    Abstract: A magnetic transfer method for magnetically transferring information signals such as servo signals from a master medium to a slave medium, capable of reducing a range of signal missing due to insufficient contact of the two mediums originating from an adhering substance, thus enhancing signal quality. When the master medium bearing an information signal and the slave medium are brought into close contact with each other, a transferring magnetic field is applied thereto, thus magnetically transferring the information signal from the master medium to the slave medium. An elastic member made of a material having an elastic property so as to deform in accordance with a surface shape of the slave medium during contact pressure application and to restore to an original surface shape thereof during release of the slave medium from the master medium can be interposed between a back of the slave medium and a pressing surface of a pressing support member.
    Type: Grant
    Filed: August 14, 2001
    Date of Patent: July 1, 2003
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Masakazu Nishikawa, Kazuyuki Usuki, Masashi Aoki
  • Patent number: 6587290
    Abstract: A master information carrier comprises a substrate whose surface has an embossed pattern corresponding to an information signal. At least a surface of the protruding portion of the embossed pattern is made of a ferromagnetic material. A method for writing an information signal into a sheet or disk magnetic record medium with a ferromagnetic thin film or coating is performed by putting the surface of the magnetic record medium into contact with the master information carrier so as to write a magnetized pattern corresponding to the embossed pattern of the master information carrier into the magnetic record medium.
    Type: Grant
    Filed: February 26, 2002
    Date of Patent: July 1, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuaki Ishida, Ryuji Sugita, Kiyokazu Tohma, Kazunari Yoshimoto, Keizou Miyata
  • Patent number: 6577459
    Abstract: The present invention provides a method for magnetic transfer and an apparatus for magnetic transfer, by which it is possible to transfer a transfer pattern with high quality from a master carrier for magnetic transfer to a slave medium by magnetic transfer regardless of position of the magnetic pattern. The method and the apparatus for magnetic transfer according to the present invention are used to apply magnetic field for transfer by bringing the master carrier for magnetic transfer into contact with the slave medium, the master carrier having a magnetic layer formed on a portion corresponding to an information signal on surface of a substrate, and the slave medium being a magnetic recording medium for receiving magnetic transfer after performing initial DC magnetization by a magnetic field by more than 1.
    Type: Grant
    Filed: June 12, 2000
    Date of Patent: June 10, 2003
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kazunori Komatsu, Makoto Nagao, Masakazu Nishikawa
  • Patent number: 6570724
    Abstract: The present invention provides a method for magnetic transfer, which including the steps of: arranging permanent magnets each magnetized symmetrically to the axis of the magnetic pole with the same polarities facing to each other and with the slave medium interposed between, and disposing the slave medium perpendicularly to the axis of the magnetic pole, rotating the slave medium or the permanent magnets in track direction; and applying magnetic field in track direction on the surface of the slave medium, whereby: after initial DC magnetization has been formed on the slave medium in advance in track direction, the master carrier for magnetic transfer and the slave medium processed by the initial DC magnetization are brought closely together, and a magnetic field for transfer in reverse direction to the direction of the initial DC magnetization on the surface of the slave medium is applied in track direction, and magnetic transfer is performed.
    Type: Grant
    Filed: April 26, 2000
    Date of Patent: May 27, 2003
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kazunori Komatsu, Makoto Nagao, Masakazu Nishikawa
  • Patent number: 6567227
    Abstract: A master information carrier comprises a substrate whose surface has an embossed pattern corresponding to an information signal. At least a surface of the protruding portion of the embossed pattern is made of a ferromagnetic material. A method for writing an information signal into a sheet or disk magnetic record medium with a ferromagnetic thin film or coating is performed by putting the surface of the magnetic record medium into contact with the master information carrier so as to write a magnetized pattern corresponding to the embossed pattern of the master information carrier into the magnetic record medium.
    Type: Grant
    Filed: March 26, 2002
    Date of Patent: May 20, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuaki Ishida, Ryuji Sugita, Kiyokazu Tohma, Kazunari Yoshimoto, Keizou Miyata, Hiroshi Ryonai
  • Publication number: 20030076611
    Abstract: In an information recording method of the present invention by carrying out recording data while carrying out tracking servo accurately, high density recording of signals at a good S/N can be carried out, and high density recording by a vertical magnetic recording system can be carried out. A magnetic disk comprises a magnetic recording layer, and the magnetic recording layer is magnetized in advance such that magnetized regions A and B having different magnetization directions are formed. At a time of recording data, vertical magnetic recording is carried out by a magnetic head while carrying out accurate tracking servo by optically tracking by a magneto-optical effect utilizing a difference in the magnetization directions of the magnetized regions A and B. Therefore, high-density recording at a good S/N is possible.
    Type: Application
    Filed: October 4, 2002
    Publication date: April 24, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Kazuyuki Usuki, Masakazu Nishikawa, Makoto Nagao
  • Publication number: 20030072095
    Abstract: A method of magnetic transfer allows transfer of magnetic signals independently to two recording layers included in a magnetic recording medium. The coercive force Hc1 of an upper recording layer, the coercive force Hc2 of a lower recording layer formed below the upper recording layer, the strength Hex2 of a first transfer magnetic field, and the strength Hex1 of a second transfer magnetic field are set so that the following relations hold true: Hc1<Hc2, Hex1<Hex2, Hc1<Hex2, and Hex1<Hc2. The first transfer magnetic field Hex2 is applied to the recording medium to transfer magnetization patterns exclusively to the lower recording layer and to uniformly magnetize the upper recording layer. The second transfer magnetic field Hex1 is applied to the recording medium to transfer magnetization patterns exclusively to the upper recording layer 1a, while keeping the magnetization patterns in the lower recording layer 1b unaffected.
    Type: Application
    Filed: September 13, 2002
    Publication date: April 17, 2003
    Inventor: Akira Saito
  • Publication number: 20030072096
    Abstract: A magnetic transfer apparatus includes a holder which contains therein a master information carrier carrying thereon information to be transferred and a slave medium to which the information born by the master information carrier is to be transferred. The master information carrier and the slave medium are pressed against each other under pressure acting on the holder when the holder is evacuated, and a transfer magnetic field is applied to the slave-medium-master-information-carrier assembly. The holder includes upper and lower holder portions having flat plate portions which are brought into abutment against the other side of the slave medium or the master information carrier and are movable toward and away from each other. At least one of the flat plate portions is flexible.
    Type: Application
    Filed: October 15, 2002
    Publication date: April 17, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventor: Akito Kamatani
  • Publication number: 20030063403
    Abstract: A master carrier for magnetic transfer is equipped with a substrate having a land/groove pattern. The land/groove pattern is formed from a magnetic material and corresponds to information that is transferred to a magnetic recording disk. Each land in the land/groove pattern has four round corners whose radius is from 1% through 47% of the width of a data track on the disk.
    Type: Application
    Filed: May 13, 2002
    Publication date: April 3, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Tadashi Yasunaga, Kazuhiro Niitsuma
  • Publication number: 20030048557
    Abstract: The present invention enables to execute accurate magnetic transfer without signal omission and the like, by bringing a master carrier which bore transfer information and a slave medium to undergo transfer into close contact with each other uniformly and without a gap when they are received in a holder and brought into confronted close contact with each other.
    Type: Application
    Filed: June 21, 2002
    Publication date: March 13, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Kazuhiro Niitsuma
  • Publication number: 20030043486
    Abstract: A magnetic-pattern transferring method is a method for transferring a magnetic pattern to a magnetic recording medium. The method comprises steps as follows. In a master transferring step, a magnetic field is applied to a master placed close to the magnetic recording medium. The magnetic field excites a magnetic layer having a pattern patterned on the master according to the magnetic pattern. Thereby, the pattern of the magnetic layer is transferred to the magnetic recording medium. In a pattern-difference measuring step, a magnetic condition of the magnetic recording medium is measured so as to measure a magnetically different part between the pattern transferred to the magnetic recording medium and the magnetic pattern. In a magnetic transferring step, a pattern transfer is performed to the magnetic recording medium by using the master while applying the magnetic field so as to correct a magnetic condition of the magnetically different part.
    Type: Application
    Filed: March 27, 2002
    Publication date: March 6, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Yutaka Nakamura, Hitoshi Komoriya, Hiroyuki Suzuki, Takao Hirahara
  • Publication number: 20030030927
    Abstract: By bring a master carrier and a slave medium into close contact with uniform force when executing magnetic transfer by applying transfer magnetic field in the state that the master carrier and slave medium is in confronted close contact and received within a holder, inferiority of transfer such as omission of signals is prevented and quality of transfer signals is enhanced.
    Type: Application
    Filed: June 13, 2002
    Publication date: February 13, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Kazuhiro Niitsuma, Akito Kamatani
  • Publication number: 20030011913
    Abstract: A magnetic transfer method includes a first step (ST103) of preparing a magnetic disk, a second step (ST105) of forming a layer of lubricant on the magnetic disk, a third step (ST108) of bringing a surface of the magnetic layer on the magnetic disk into close contact with a magnetic transfer master having a magnetic film formed on at least one side and magnetically transferring a pattern of the magnetic film on the magnetic transfer master onto the surface of the magnetic disk through application of an external magnetic field, and a fourth step (ST104, ST106) of burnishing at least a surface of the magnetic disk that comes into contact with the magnetic transfer master. The first step, the fourth step, the second step, the fourth step, and the third step are performed in the stated order.
    Type: Application
    Filed: August 6, 2002
    Publication date: January 16, 2003
    Inventors: Hideyuki Hashi, Taizou Hamada, Tatsuaki Ishida, Kiyokazu Tohma
  • Publication number: 20030011912
    Abstract: A master carrier for magnetic transfer is equipped with a substrate with a land/groove pattern of lands and grooves, and a magnetic layer formed on the land/groove pattern. The adhesion between the substrate and the magnetic layer is 1.2×109 N/m2 or greater. A first oxygen concentration Do at the magnetic layer formed on the land is reduced gradually toward the direction of the depth of the substrate and is greater than a second oxygen concentration Dh at the magnetic layer formed on the groove.
    Type: Application
    Filed: June 25, 2002
    Publication date: January 16, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Tadashi Yasunaga
  • Publication number: 20030002182
    Abstract: A magnetic transfer device for bringing a master carrier with information and a slave medium into intimate contact with each other and then applying a transfer field to transfer the information to the slave medium. The master carrier has an inclined face on its radially outer end. After the magnetic transfer of the information, claws are inserted in the gas formed by the inclined face of the master carrier and the slave medium. The slave medium held in intimate contact with the master carrier is separated from the master carrier by lifting the slave medium with the claws.
    Type: Application
    Filed: May 14, 2002
    Publication date: January 2, 2003
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Akito Kamatani, Masakazu Nishikawa, Makoto Nagao, Kazunori Komatsu, Tsuneo Inui, Kazuhiro Niitsuma
  • Publication number: 20020186488
    Abstract: An accurate magnetic transfer to a high-density slave medium having two magnetic layers and utilizing antiferromagnetic coupling is performed. By applying a first magnetic field that causes both the first and second magnetic layers of the magnetic layer of a slave medium to reach saturation magnetization unidirectionally along the circumferential direction of the track, the first and second magnetic layers are magnetized uniformly in the same direction as the first magnetic field. Then, a second magnetic field that inverts the magnetization of the first magnetic layer and has no effect on the magnetization of the second magnetic layer is applied in the opposite direction, whereby only the magnetization direction of the first magnetic layer is inverted in the direction of the second magnetic field. Thereby, a favorable initial magnetization state in which the magnetization directions of the first and second magnetic layers are oriented antiparallel can be obtained.
    Type: Application
    Filed: June 7, 2002
    Publication date: December 12, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Tadashi Yasunaga
  • Publication number: 20020186487
    Abstract: A method of performing an accurate magnetic transfer to a high-density slave medium having two magnetic layers and utilizing antiferromagnetic coupling. The magnetic layer, which has been initially magnetized in advance, of a magnetic recording medium is conjoined with the data bearing surface of a master medium. A transfer magnetic field is applied to the conjoined body in the circumferential direction of the track of the first magnetic layer in the direction opposite the initial magnetization direction of the second magnetic layer. At this time, the thickness of the magnetic layer of the master medium, the permeability (material) of the magnetic layer, the form of the patterned magnetic layer, the separation distance between the master medium and the magnetic recording medium, etc., may be controlled so that the magnetic field of the transfer magnetic field does not effect the magnetization state of the first magnetic layer.
    Type: Application
    Filed: June 7, 2002
    Publication date: December 12, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Tadashi Yasunaga
  • Publication number: 20020186486
    Abstract: Signal omissions are prevented from occurring in the magnetic data transferred to a slave medium by magnetic transfer employing a magnetic transfer master medium. A master medium formed of a material and having a thickness wherein the bow stiffness=Ebd3/12 thereof is in the range greater than or equal to 0.03 N·m2 and less than or equal to 27 N·m2, for a sample piece thereof having a width defined of 1 m and an arbitrary length, and utilizing the Young's modulus E obtained by use of a vibration reed method on sample having a length of 50 mm, an arbitrary width b, and a thickness d.
    Type: Application
    Filed: May 14, 2002
    Publication date: December 12, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Masashi Aoki
  • Publication number: 20020171958
    Abstract: A favorable magnetic transfer is performed on a perpendicular magnetic recording medium. A permanent magnet apparatus provided with two permanent magnets, each having a width extending the length of the radial direction of a discoid magnetic recording medium, is used as a transfer magnetic field generating means. A conjoined body formed of the perpendicular magnetic recording medium, which has been initially magnetized unidirectionally in the direction perpendicular to the track surface thereof, and two master mediums, disposed on respective surfaces of the slave medium, is inserted between the permanent magnets. A rotating means rotates the conjoined body, in the direction along the tracks of the slave medium, while a transfer magnetic field is applied to the conjoined body in the direction substantially opposite that in which the initial magnetization of the magnetic layer of magnetic recording medium has been performed, so as to perform the magnetic transfer.
    Type: Application
    Filed: May 20, 2002
    Publication date: November 21, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Kazunori Komatsu, Masakazu Nishikawa
  • Publication number: 20020171957
    Abstract: A favorable magnetic transfer is performed on a vertical magnetic recording medium. A permanent magnet apparatus employs a transfer magnetic field generating means provided with two columnar permanentmagnets, each having a cross-sectional surface are equal to or greater than that of the track surface of the slave medium. A conjoined body formed of a slave medium, which has been initially magnetized unidirectionally in the direction perpendicular to the track surface thereof, and two master mediums, disposed on respective surfaces of the slave medium, is inserted between the permanent magnets so that a transfer magnetic field can be applied thereto in the direction substantially opposite that in which the initial magnetization has been performed. A uniform transfer magnetic field is applied over the entirety of track surface of the slave medium so as to simultaneously perform a magnetic transfer over the entirety of the track surface.
    Type: Application
    Filed: May 17, 2002
    Publication date: November 21, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Kazunori Komatsu, Masakazu Nishikawa
  • Publication number: 20020167744
    Abstract: A magnetic transfer wherein the exchange of master mediums is made easy to perform is provided, whereby the operational efficiency and transfer efficiency are improved, leading to an overall improvement in productivity in the manufacture of preformatted slave mediums. A master fixing base for determining and supporting the position of a master medium, which bears transfer data, and a conjoining apparatus for conjoining the master medium and the slave medium that is to receive the transfer therefrom are provided. The master medium is exchanged along with the master fixing base. It is preferable that a cleaning means be provided.
    Type: Application
    Filed: April 15, 2002
    Publication date: November 14, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Akito Kamatani, Tsuneo Inui, Masashi Aoki, Masakazu Nishikawa
  • Publication number: 20020163747
    Abstract: When executing a magnetic transfer by bringing a master medium and a slave medium into close contact with each other and applying a transferring magnetic field, a permitted limit of the application direction of the transferring magnetic field is defined so that magnetic patterns can be accurately transferred. A slave medium 2 is previously initial DC magnetized in a track direction by applying a magnetic field to the slave medium in the track direction of a slave surface, and when executing a magnetic transfer by bringing the master medium 3 and the slave medium 2 into close contact with each other and applying the transferring magnetic field in the track direction of the slave surface, the application angle &agr; of the transferring magnetic field is defined within a range of ±30° in a vertical direction with respect to the slave surface.
    Type: Application
    Filed: February 21, 2002
    Publication date: November 7, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Kazunori Komatsu, Masakazu Nishikawa
  • Publication number: 20020159174
    Abstract: Instead of directly performing defect inspection using a master information carrier, an inspection substrate is prepared to then bring the master information carrier in close contact therewith, to thereby transfer a defect on the master information carrier to the inspection substrate, thus indirectly inspecting any defect of the master information carrier on the inspection substrate. Defect inspection is performed on the first-state inspection substrate before close contacting, so that a defect inspection result on the second-state inspection substrate after close contacting and that on the first-state inspection substrate are compared to each other.
    Type: Application
    Filed: April 17, 2002
    Publication date: October 31, 2002
    Applicant: Matsushita Electric Industrial Co. Ltd.
    Inventors: Hideyuki Hashi, Taizou Hamada, Tatsuaki Ishida
  • Publication number: 20020159173
    Abstract: A master information carrier capable of manufacturing a magnetic recording medium in which a preformat recording of information signals causing no reproduction signal detection errors arising from a pulse shift of a reproduction waveform is performed. A master information carrier 1 has an array of ferromagnetic thin films 3 arranged according to the pattern of information signals and is used for forming magnetization 4 of a pattern corresponding to the array pattern of the ferromagnetic thin film 3 in a magnetic recording medium by applying a magnetic field while opposing the master information carrier 1 against a magnetic recording medium 2. Each of the ferromagnetic thin films 3 is formed such that each pattern length A becomes equal to a length including a correction amount &agr; in addition to a length a between magnetic transition areas 6 of the magnetization 4 to be formed in the magnetic recording medium 2.
    Type: Application
    Filed: November 27, 2001
    Publication date: October 31, 2002
    Inventors: Tatsuaki Ishida, Keizo Miyata, Nobuyuki Komura, Yasuaki Ban, Taizuo Hamada, Hideyuki Hashi
  • Patent number: 6469848
    Abstract: In the recording method of the present invention, the surface of a master information carrier facing a recording medium becomes slightly concave in its center when the master information carrier is placed upon and brought into tight contact with the recording medium, and information signals are transferred and recorded onto the recording medium. The recording method of the present invention can be widely used for producing disk-type recording media with a hole such as magnetic disks, photomagnetic disks and optical disks. The recording method of the present invention achieves quick and productive production of a very flat and smooth recording medium that is free of fine dust. Furthermore, high-density information signals can be recorded evenly and firmly on the whole surface of the magnetic surface of the magnetic recording medium.
    Type: Grant
    Filed: February 27, 2001
    Date of Patent: October 22, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Taizo Hamada, Hideyuki Hashi
  • Publication number: 20020141088
    Abstract: In the magnetic transferring method for magnetically transferring an information signal such as a servo signal from the master medium to the slave medium, when magnetic transfer is performed by bringing a master medium and a slave medium into close contact with each other, the master medium bearing an information signal and the slave medium having a lubricating layer formed on the surface of its recording plane during use, and applying a transfer magnetic field, the magnetic transfer is performed by bringing the slave medium before the formation of the lubricating layer and the master medium into close contact with each other. Thus, the separation of the slave medium from the master medium after the magnetic transfer is facilitated and the adsorption of dust on the slave medium is prevented.
    Type: Application
    Filed: February 8, 2002
    Publication date: October 3, 2002
    Applicant: Fuji Photo Film Co., Ltd
    Inventors: Masakazu Nishikawa, Makoto Nagao
  • Patent number: 6433944
    Abstract: The present invention provides a master carrier for magnetic transfer, comprising a plurality of transfer information recording sectors having recording information magnetized thereon, a non-magnetic-material sector defining each of the transfer information recording sectors is present between each of adjacent transfer information recording sectors, and surfaces of the transfer information recording sectors and surfaces of the non-magnetic material sectors are positioned on and form the same plane.
    Type: Grant
    Filed: September 22, 1999
    Date of Patent: August 13, 2002
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Makoto Nagao, Kazutoshi Katayama, Ryuji Sugita
  • Publication number: 20020101669
    Abstract: A master information carrier comprises a substrate whose surface has an embossed pattern corresponding to an information signal. At least a surface of the protruding portion of the embossed pattern is made of a ferromagnetic material. A method for writing an information signal into a sheet or disk magnetic record medium with a ferromagnetic thin film or coating is performed by putting the surface of-the magnetic record medium into contact with the master information carrier so as to write a magnetized pattern corresponding to the embossed pattern of the master information carrier into the magnetic record medium.
    Type: Application
    Filed: March 26, 2002
    Publication date: August 1, 2002
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuaki Ishida, Ryuji Sugita, Kiyokazu Tohma, Keizou Miyata, Hiroshi Ryonai
  • Publication number: 20020101670
    Abstract: A master information carrier comprises a substrate whose surface has an embossed pattern corresponding to an information signal. At least a surface of the protruding portion of the embossed pattern is made of a ferromagnetic material. A method for writing an information signal into a sheet or disk magnetic record medium with a ferromagnetic thin film or coating is performed by putting the surface of the magnetic record medium into contact with the master information carrier so as to write a magnetized pattern corresponding to the embossed pattern of the master information carrier into the magnetic record medium.
    Type: Application
    Filed: March 26, 2002
    Publication date: August 1, 2002
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuaki Ishida, Ryuji Sugita, Kiyokazu Tohma, Keizou Miyata, Hiroshi Ryonai
  • Publication number: 20020089768
    Abstract: A master information carrier comprises a substrate whose surface has an embossed pattern corresponding to an information signal. At least a surface of the protruding portion of the embossed pattern is made of a ferromagnetic material. A method for writing an information signal into a sheet or disk magnetic record medium with a ferromagnetic thin film or coating is performed by putting the surface of the magnetic record medium into contact with the master information carrier so as to write a magnetized pattern corresponding to the embossed pattern of the master information carrier into the magnetic record medium.
    Type: Application
    Filed: February 26, 2002
    Publication date: July 11, 2002
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuaki Ishida, Ryuji Sugita, Kiyokazu Tohma, Kazunari Yoshimoto, Keizou Miyata, Hiroshi Ryonai
  • Publication number: 20020089769
    Abstract: A master information carrier comprises a substrate whose surface has an embossed pattern corresponding to an information signal. At least a surface of the protruding portion of the embossed pattern is made of a ferromagnetic material. A method for writing an information signal into a sheet or disk magnetic record medium with a ferromagnetic thin film or coating is performed by putting the surface of the magnetic record medium into contact with the master information carrier so as to write a magnetized pattern corresponding to the embossed pattern of the master information carrier into the magnetic record medium.
    Type: Application
    Filed: February 26, 2002
    Publication date: July 11, 2002
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuaki Ishida, Ryuji Sugita, Kiyokazu Tohma, Kazunari Yoshimoto, Keizou Miyata, Hiroshi Ryonai
  • Publication number: 20020080507
    Abstract: A magnetic transcription device for transcribing information signals of a master information carrier in a magnetic recording medium by applying a magnetic field generated by magnetic field generating means to a contact body obtained by contacting the master information carrier having a base on which ferromagnetic bodies corresponding to the information signals are formed with a magnetic recording medium having a ferromagnetic layer, wherein the magnetic recording medium includes driving means for adjusting a distance between the magnetic field generating means and the contact body while rotating the magnetic field generating means relative to the contact body.
    Type: Application
    Filed: December 3, 2001
    Publication date: June 27, 2002
    Applicant: Matsushita Electric Industrial Co., Ltd
    Inventors: Kouji Taniguchi, Kaoru Matsuoka, Taizou Hamada, Hideyuki Hashi, Yasuaki Ban, Tatsuaki Ishida
  • Publication number: 20020075582
    Abstract: A magnetic transfer apparatus includes an inexpensive and small adjusting mechanism for adjusting the positions of the magnetic heads, that facilitates preventing anomaly of drastically changing transferred signal intensity, and a very rigid mounting mechanism for mounting the magnetic heads. The magnetic transfer apparatus includes a magnetic field application means for magnetic transfer, the magnetic field application means applying a magnetic field to the master disc and the perpendicular magnetic recording medium positioned in tight contact with each other or in close proximity to each other, the magnetic field application means including a pair of magnetic heads for magnetic transfer positioned symmetrically with respect to the surface of the perpendicular magnetic recording medium facing to the master disc, the magnetic heads moving always keeping their symmetrical positional relation ship with respect to the surface of the perpendicular magnetic recording medium facing to the master disc.
    Type: Application
    Filed: October 13, 2001
    Publication date: June 20, 2002
    Inventor: Yukihiro Takano
  • Publication number: 20020075583
    Abstract: A master information carrier comprises a substrate whose surface has an embossed pattern corresponding to an information signal. At least a surface of the protruding portion of the embossed pattern is made of a ferromagnetic material. A method for writing an information signal into a sheet or disk magnetic record medium with a ferromagnetic thin film or coating is performed by putting the surface of the magnetic record medium into contact with the master information carrier so as to write a magnetized pattern corresponding to the embossed pattern of the master information carrier into the magnetic record medium.
    Type: Application
    Filed: December 21, 2001
    Publication date: June 20, 2002
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuaki Ishida, Ryuji Sugita, Kiyokazu Tohma, Kazunari Yoshimoto, Keizou Miyata, Hiroshi Ryonai
  • Publication number: 20020063981
    Abstract: A master information carrier is made to overlap with a magnetic recording medium being a magnetic recording medium in an adhering state, and a pattern corresponding to information signals on the master information carrier is transferred to the magnetic recording medium, thereby magnetically transferring a magnetized pattern of information signals to the magnetic recording medium. Thereafter, an urging force to the magnetic recording medium side is applied to the master information carrier, and in the urging force applied state, a gas under pressure is supplied on the adhering/joining surfaces of the master information carrier and the magnetic recording medium, thereby releasing the adhering state of the master information carrier and the magnetic recording medium. Then, the application of the urging force is released to continue the supply of the gas under pressure, thereby pulling away the master information carrier from the magnetic recording medium and moving them.
    Type: Application
    Filed: November 28, 2001
    Publication date: May 30, 2002
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Taizou Hamada, Hideyuki Hashi
  • Publication number: 20020054442
    Abstract: Magnetic transfer of information signals such as servo signals from a master carrier to a slave media is prevented from degradation of transfer quality caused by imperfect contact of the master carrier with the slave medium attributable to dust adhesion. Specifically, when the master carrier that bears the information signals is brought into close contact with the slave medium for performing magnetic transfer by application of a magnetic field thereto, the slave medium, with its recording surface facing vertically, is conveyed toward the master carrier, held by a contact means with its information-bearing surface facing vertically. Then the master carrier and the slave medium are brought into close contact with each other and subjected to magnetic transfer with contact surfaces thereof set vertically, whereby adhesion and deposition of floating dust or the like are prevented.
    Type: Application
    Filed: November 7, 2001
    Publication date: May 9, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventor: Masakazu Nishikawa
  • Publication number: 20020051307
    Abstract: The present invention provides a magnetic transfer method for transferring information by bringing a master carrier for magnetic transfer and a slave medium into close contact with each other and by applying a magnetic field for transfer, said master carrier comprising servo areas and data areas, said servo areas are designed on convex form, and difference of height between the data area and the servo area is within the range of 50-800 nm.
    Type: Application
    Filed: August 31, 2001
    Publication date: May 2, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Seiichi Watanabe
  • Publication number: 20020051306
    Abstract: The present invention provides a magnetic transfer method for transferring information by bringing a master carrier for magnetic transfer and a slave medium into close contact with each other and by applying a magnetic field for magnetic transfer, said master carrier of magnetic transfer comprising servo areas to be transferred from the master carrier to the slave medium and data areas not to be transferred, both on the same plane.
    Type: Application
    Filed: August 31, 2001
    Publication date: May 2, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Seiichi Watanabe
  • Publication number: 20020048106
    Abstract: A high-level region and a low-level region are formed on a surface of a nonmagnetic base member, in which high-level region is formed a ferromagnetic thin film pattern which corresponds to a preformat information signal, in such a structure that a flow promoting shape of such a shape (e.g., smooth curved shape, polygonal shape) that inhibits the stagnation of a flow of a detergent to promote the flow in order to prevents sticking and residing of foreign matter contained in the detergent is formed at an area where the detergent is liable to stagnate in the high-level region, i.e. at an inner radial portion of a disk-shaped mater information carrier.
    Type: Application
    Filed: October 23, 2001
    Publication date: April 25, 2002
    Applicant: Matsushita Electric Industrial Co., Ltd
    Inventors: Keizo Miyata, Hideyuki Hashi, Tatsuaki Ishida
  • Publication number: 20020034028
    Abstract: Disclosed is a magnetic transfer method magnetically transferring information signals such as servo signals from a master medium to a slave medium, which is capable of preventing the occurrence of missing signals due to insufficient contact of the master medium and the slave medium originating from adhering of dust to the slave medium, thus increasing reliability. When the master medium bearing information signals and the slave medium are brought into close contacted with each other, and when a transfer magnetic field is applied to the master medium and the slave medium to magnetically transfer the information signal from the master medium to the slave medium, a metal thin film formed on a substrate of the master medium is electrically grounded, and charges of the master medium are removed, thus reducing a quantity of adhering dust.
    Type: Application
    Filed: August 3, 2001
    Publication date: March 21, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masakazu Nishikawa, Makoto Nagao
  • Publication number: 20020030909
    Abstract: A magnetic transfer apparatus capable of enhancing the quality of a transfer signal by improving close contact property between master and slave media in magnetic transfer carried out to magnetically transfer an information signal such as a servo signal from the master medium to the slave medium. In the magnetic transfer specifically carried out by applying a transfer magnetic field in a close contact state of the master medium bearing information and the slave medium, the master and slave media are closely contacted with each other in a state where the backside of the master medium is adsorbed and held on the flat adsorbing surface of an adsorbing member to heighten the flatness of the master medium. In the case of one-surface transfer, preferably, an elastic body is closely contacted with the surface opposite to the master medium on the slave medium.
    Type: Application
    Filed: September 12, 2001
    Publication date: March 14, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Masashi Aoki, Akito Kamatani
  • Publication number: 20020030910
    Abstract: In magnetic transfer performed to transfer an information signal such as a servo signal from a master medium to a slave medium, the degradation of transfer quality caused by a failure of close contact between the master medium and the slave medium due to dust accumulated thereon is prevented. Magnetic transfer means is provided to carry out the magnetic transfer by bringing the master medium bearing information and the slave medium into close contact with each other, and applying a transfer magnetic field. Replacing means is provided to prepare a plurality of master media, and replacing the master medium after magnetic transfer is performed a predetermined number of times. Cleaning means is also provided to clean the replaced master medium by ultrasonic washing or the like.
    Type: Application
    Filed: September 12, 2001
    Publication date: March 14, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventor: Tsuneo Inui