Patents by Inventor Mitsuru Takai

Mitsuru Takai 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: 7166318
    Abstract: A production method and a production apparatus for a magnetic recording medium, which enable the efficient production of a discrete type magnetic recording medium, while reliably preventing any deterioration of the partitioned recording elements.
    Type: Grant
    Filed: March 4, 2004
    Date of Patent: January 23, 2007
    Assignee: TDK Corporation
    Inventors: Kazuhiro Hattori, Mitsuru Takai, Takahiro Suwa
  • Patent number: 7149338
    Abstract: There are provided a next process-determining method capable of determining a next process to be carried out next objectively and at the same time in a short time period, as well as an inspecting method and apparatus which are capable of carrying out a predetermined inspection as to an object to be inspected according to the next process-determining method. A sample object is digitized to sample data formed by digital data. The sample data is compressed into compressed sample data according to a predetermined data format. There is calculated a difference data amount between a data amount of the compressed sample data and a data amount of reference data formed by digitizing and compressing a reference sample object in the same manner as the sample object is processed. Which of a plurality of predetermined numerical ranges the difference data amount belongs to is identified.
    Type: Grant
    Filed: February 28, 2002
    Date of Patent: December 12, 2006
    Assignee: TDK Corporation
    Inventors: Mitsuru Takai, Takahiro Suwa
  • Publication number: 20060275692
    Abstract: A method for forming a concavo-convex pattern that can form a fine and complex concavo-convex pattern such as that corresponding to servo information with high precision, a method for manufacturing a master disk, a method for manufacturing a stamper, and a method for manufacturing a magnetic recording medium using that method for forming a concavo-convex pattern are provided. A resin layer formed over a resin layer supporting member is processed into an irregular concavo-convex pattern in which a dividing convex portion is formed in a part of concave portions of a predetermined basic concavo-convex pattern and at least some of concave portions are divided as compared with corresponding concave portions of the basic concavo-convex pattern. A recording layer (the resin layer supporting member) is etched based on the resin layer to be processed into a concavo-convex pattern obtained by bringing the irregular concavo-convex pattern close to the basic concavo-convex pattern.
    Type: Application
    Filed: June 2, 2006
    Publication date: December 7, 2006
    Applicant: TDK CORPORATION
    Inventors: Shuichi Okawa, Katsuyuki Nakada, Kazuhiro Hattori, Mitsuru Takai
  • Publication number: 20060269791
    Abstract: A magnetic recording medium which has a recording layer of concavo-convex pattern and has high production efficiency, a magnetic recording and reproducing apparatus which has the magnetic recording medium, a stamper for manufacturing the magnetic recording medium, a method of manufacturing the stamper, and a method of manufacturing the magnetic recording medium are provided. Part of servo areas of the recording layer are formed in an irregular servo concavo-convex pattern in which at least some of either concave portions or convex portions are divided in a radial direction as compared with those of a basic servo concavo-convex pattern, the basic servo concavo-convex pattern having concave portions consisting of concave unit areas corresponding to cell areas for recording either an information on 0 or an information on 1, and convex portions consisting of convex unit areas corresponding to the other cell areas for recording the other information.
    Type: Application
    Filed: May 30, 2006
    Publication date: November 30, 2006
    Applicant: TDK CORPORATION
    Inventors: Shuichi Okawa, Katsuyuki Nakada, Kazuhiro Hattori, Mitsuru Takai
  • Publication number: 20060188751
    Abstract: A magnetic recording medium is provided that includes a recording layer having recording elements formed as convex portions and a filling material filled within the concave portions between the recording elements. The medium is highly reliable and has a surface less liable to damages when a magnetic head contacts the surface, so that good recording/reproducing characteristics are ensured. The magnetic recording medium includes a recording layer formed in a predetermined concavo-convex pattern over a substrate and having recording elements formed as convex portions in the concavo-convex pattern and a filling material filled within the concave portions between the recording elements. The filling material is substantially composed of Si and O, and the ratio of the number of O atoms to the number of Si atoms is equal to or more than 1.5 and less than 2.
    Type: Application
    Filed: January 19, 2006
    Publication date: August 24, 2006
    Applicant: TDK CORPORATION
    Inventors: Shuichi Okawa, Mitsuru Takai, Kazuya Shimakawa
  • Publication number: 20060132970
    Abstract: A perpendicular magnetic recording/reproducing device that can suppress broadening of recording magnetic fields and that is capable of effective application of magnetic field to a recording target track is provided. The device includes a magnetic recording medium having a soft magnetic layer and a recording layer having a perpendicular magnetic anisotropy formed in this order over a substrate, and a magnetic head. The soft magnetic layer is formed with a concavo-convex pattern in which at least part of regions corresponding to tracks of the recording layer protrudes toward the recording layer, and convex portions are provided with the magnetic anisotropy in the circumferential direction of the tracks. The magnetic head includes a main pole for generating a recording magnetic field, and a return pole to which the magnetic field returns, the main pole and the return pole being arranged side by side in a track width direction.
    Type: Application
    Filed: December 9, 2005
    Publication date: June 22, 2006
    Applicant: TDK CORPORATION
    Inventors: Mitsuru Takai, Katsumichi Tagami, Kazuya Shimakawa
  • Publication number: 20060115584
    Abstract: A manufacturing method and a manufacturing apparatus of a magnetic recording medium are provided, which can efficiently manufacture a magnetic recording medium having good magnetic characteristics while suppressing warpage of the medium, magnetic degradation of divided recording elements, and misalignment of the processed shape of the divided recording elements. In the manufacturing method and the manufacturing apparatus, both surfaces of an object to be processed 10 are simultaneously processed. As a dry etching technique for a continuous recording layer 20, ion beam etching is employed. A resist layer 26 is removed before dry etching of the continuous recording layer 20.
    Type: Application
    Filed: August 3, 2004
    Publication date: June 1, 2006
    Applicant: TDK Corporation
    Inventors: Kazuhiro Hattori, Mitsuru Takai
  • Publication number: 20060063042
    Abstract: A magnetic recording medium is provided in which a magnetic recording layer 5 is provided in a predetermined concavo-convex pattern on a substrate 1A, a concave portion in a concavo-convex pattern is filled with a non-magnetic material, and a non-magnetic layer 16 formed of the non-magnetic material positioned at the bottom surface of the concave portion in the non-magnetic materials is formed on a convex portion of the concavo-convex pattern while surface of the convex portion and the concave portion is substantially flattened, and a thickness of the non-magnetic layer 16 is 1 nm or less.
    Type: Application
    Filed: August 19, 2005
    Publication date: March 23, 2006
    Applicant: TDK Corporation
    Inventors: Mitsuru Takai, Kazuhiro Hattori, Takahiro Suwa, Shuichi Okawa
  • Publication number: 20060021966
    Abstract: A manufacturing method of a magnetic recording medium, and the like are provided, which can suppress misalignment of a processed shape of divided recording elements and magnetic degradation and can efficiently manufacture a magnetic recording medium having good magnetic characteristics. In the manufacturing method, ion beam etching is used as a dry etching technique for a continuous recording layer 20. Before dry etching of the continuous recording layer 20, a resist layer 26 is removed. As the material for a first mask layer covering the continuous recording layer, diamond like carbon is used.
    Type: Application
    Filed: July 28, 2004
    Publication date: February 2, 2006
    Inventors: Kazuhiro Hattori, Mitsuru Takai, Shuichi Okawa
  • Publication number: 20050287397
    Abstract: A magnetic recording medium is provided which has good recording/reproducing characteristics with a recording layer divided in a number of recording elements by a predetermined concavo-convex pattern, and a manufacturing method that enables efficient manufacture of such a magnetic recording medium. The magnetic recording medium includes a substrate, a soft magnetic layer formed over the substrate, a recording layer formed over the soft magnetic layer such as to have magnetic anisotropy in a direction perpendicular to surface, and being divided in a number of recording elements by a predetermined concavo-convex pattern, and a non-magnetic intermediate layer formed between the recording layer and the soft magnetic layer. The recording elements are formed to have a predetermined track shape in a data region.
    Type: Application
    Filed: May 24, 2005
    Publication date: December 29, 2005
    Applicant: TDK CORPORATION
    Inventors: Yoshikazu Soeno, Mitsuru Takai, Katsumichi Tagami, Kazuya Shimakawa
  • Publication number: 20050284842
    Abstract: The recording layer (to-be-etched layer), a main mask layer, and a sub mask layer are formed in this order over a substrate, and the sub mask layer is processed into a predetermined concavo-convex pattern. Next, parts of the main mask layer under the concave portions are removed by reactive ion etching using oxygen or ozone as the reactive gas. Parts of the recording layer under the concave portions are also removed by dry etching, whereby the recording layer is shaped into the concavo-convex pattern. The main mask layer is chiefly made of carbon. The sub mask layer is made of a material having an etching rate lower than that of carbon with respect to the reactive ion etching in the step of processing the main mask layer.
    Type: Application
    Filed: June 21, 2005
    Publication date: December 29, 2005
    Applicant: TDK Corporation
    Inventors: Shuichi Okawa, Kazuhiro Hattori, Mikiharu Hibi, Mitsuru Takai
  • Publication number: 20050263915
    Abstract: An imprinting method which is capable of forming a concave/convex pattern in a short time without causing deformation or incompleteness of the pattern. In the imprinting method, a stamper-pressing step of pressing a stamper against a resin layer formed by applying a resin material to a surface of a substrate, in a state of the resin layer being heated to a predetermined temperature, and a stamper-removing step of removing the stamper from the resin layer while maintaining either of the state of the resin layer being heated and a state of the temperature of the heated resin layer being held, are performed in the mentioned order, whereby shapes of recesses/protrusions of the stamper are transferred to the resin layer to form a concave/convex pattern on the substrate.
    Type: Application
    Filed: March 24, 2005
    Publication date: December 1, 2005
    Applicant: TDK Corporation
    Inventors: Minoru Fujita, Kazuhiro Hattori, Yoshikazu Soeno, Mitsuru Takai
  • Publication number: 20050243467
    Abstract: A magnetic recording medium having high reliability is provided, in which concave portions between recording elements formed as convex portions of a concavo-convex pattern are approximately completely filled with a non-magnetic material. The magnetic recording medium is a plate-like body including: a substrate; a recording layer that is formed in a predetermined concavo-convex pattern over the substrate and includes recording elements for recording information formed as convex portions of the concavo-convex pattern; and the non-magnetic material filling concave portions between the recording elements. Side faces of the recording elements are inclined to face a surface of the plate-like body on a side toward which the recording elements 16 project in the concavo-convex pattern. An inclination angle of the side faces of the recording elements with respect to a direction perpendicular to that surface is smaller than 90° and 5° or more.
    Type: Application
    Filed: April 27, 2005
    Publication date: November 3, 2005
    Applicant: TDK CORPORATION
    Inventors: Mitsuru Takai, Yoshikazu Soeno, Katsumichi Tagami, Kazuya Shimakawa
  • Publication number: 20050233176
    Abstract: In an information recording medium where respective concave parts of a magnetic layer, which is formed on at least one side e of a substrate and in which a predetermined convex/concave pattern has been formed, are filled with non-magnetic material and non-magnetic layers are formed by the non-magnetic material in at least partial regions of respective upper surfaces of respective convex parts of the magnetic layer, the non-magnetic layers are formed so that parts thereof protrude further in a direction in which the convex parts protrude than other parts of the non-magnetic layers.
    Type: Application
    Filed: March 22, 2005
    Publication date: October 20, 2005
    Applicant: TDK Corporation
    Inventors: Mitsuru Takai, Yoshikazu Soeno, Katsumichi Tagami, Kazuya Shimakawa, Takahiro Suwa
  • Publication number: 20050213239
    Abstract: A magnetic recording medium including at least a disk substrate 1A, a magnetic recording layer 5 formed with a predetermined concavo-convex pattern on the disk substrate 1A, and a non-magnetic layer 6 filled into concave portions of the concavo-convex pattern, so as to have data track regions 20 and servo pattern regions 21. Due to the existence of concaves and convexes in the surface of each servo pattern region 21, the foregoing problem is solved. On this occasion, arithmetical mean deviation of the assessed profile Ra of the surface of each servo pattern region 21 is preferably not lower than 0.3 nm. The difference in surface level between each concave and each convex existing in the surface of the servo pattern region 21 is preferably not larger than 6 nm.
    Type: Application
    Filed: February 22, 2005
    Publication date: September 29, 2005
    Applicant: TDK Corporation
    Inventors: Mikiharu Hibi, Mitsuru Takai, Kazuya Shimakawa
  • Publication number: 20050196650
    Abstract: A magnetic recording medium includes at least a disk substrate 1, a magnetic recording layer 5 formed with a predetermined concavo-convex pattern on the disk substrate 1, and a non-magnetic layer 6 formed in concave portions of the concavo-convex pattern. Convex shapes made of a non-magnetic material are formed on the magnetic recording layer 5 or the non-magnetic layer 6. Each convex shape is formed, for example, into a mountain-like shape whose upper surface width (W1 or W2) is made smaller than width W5 of each convex portion of the magnetic recording layer 5 or width W6 of each concave portion where the non-magnetic layer 6 is formed.
    Type: Application
    Filed: February 24, 2005
    Publication date: September 8, 2005
    Applicant: TDK Corporation
    Inventors: Takahiro Suwa, Mitsuru Takai, Kazuhiro Hattori, Shuichi Okawa, Mikiharu Hibi
  • Publication number: 20050191526
    Abstract: A magnetic recording medium including at least a disk substrate 1A, a magnetic recording layer 5 formed with a predetermined concavo-convex pattern on the disk substrate 1A, and a non-magnetic layer 6 filled into concave portions of the concavo-convex pattern, so as to have data track regions 20 and servo pattern regions 21. Due to the existence of concaves and convexes in the surface of each data track region 20, the foregoing problem is solved. On this occasion, arithmetical mean deviation of the assessed profile Ra of the surface of each data track region 20 is preferably not lower than 0.3 nm. The difference in surface level between each concave and each convex existing in the surface of the data track region 20 is preferably not larger than 6 nm.
    Type: Application
    Filed: February 22, 2005
    Publication date: September 1, 2005
    Applicant: TDK Corporation
    Inventors: Minoru Fujita, Mitsuru Takai, Kazuya Shimakawa
  • Publication number: 20050193405
    Abstract: A magnetic recording and reproducing device includes: a magnetic recording medium in which a magnetic recording layer is formed in a concavo-convex pattern so that tracks are formed by convex portions of a predetermined track width and arranged in parallel in the track width direction; a heating head for heating the magnetic recording medium to partially reduce coercivity of the tracks; a recording head for applying a recording magnetic field to a heated portion of the magnetic recording medium to record magnetic data on the tracks; and a reproducing head for detecting a reproducing magnetic field of the tracks. In this configuration, an effective recording area has an effective recording width that is equal to or more than the track width, and equal to or less than a sum of the track width and a doubled value of width of concave portions between the tracks.
    Type: Application
    Filed: February 14, 2005
    Publication date: September 1, 2005
    Applicant: TDK CORPORATION
    Inventors: Kazuhiro Hattori, Yoshikazu Soeno, Mitsuru Takai, Shuichi Okawa
  • Publication number: 20050185561
    Abstract: A magnetic recording medium is provided, which has a recording layer formed in a concavo-convex pattern and makes it possible to obtain the stable flying characteristics of a head. In the magnetic recording medium, concave portions between recording elements are filled with a non-magnetic material. Thus, the surface of the magnetic recording medium takes a concavo-convex shape which is different from the concavo-convex pattern of the recording layer. Also, the arithmetical mean deviation of the assessed profile of the concavo-convex shape in the surface is restricted to 1 nm or less.
    Type: Application
    Filed: February 17, 2005
    Publication date: August 25, 2005
    Applicant: TDK CORPORATION
    Inventors: Kazuhiro Hattori, Mitsuru Takai
  • Publication number: 20050161427
    Abstract: A method of working a workpiece containing magnetic material and a method of manufacturing a magnetic recording medium capable of effectively manufacturing a magnetic recording medium and a magnetic recording and reproducing device, in that a workpiece containing magnetic material is worked by means of dry etching and washed in an alkaline solution, for example, the workpiece is subjected to scrubbing or ultrasonic washing.
    Type: Application
    Filed: January 21, 2005
    Publication date: July 28, 2005
    Applicant: TDK Corporation
    Inventors: Shuichi Okawa, Kazuhiro Hattori, Mitsuru Takai