Patents by Inventor Iwao Okamoto
Iwao Okamoto 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).
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Patent number: 9548073Abstract: Systems and methods for providing high performance soft magnetic underlayers for magnetic recording media are described. One such magnetic recording medium includes a substrate, an amorphous soft magnetic underlayer including CoFeMoNb on the substrate, where an atomic percent of the Mo is greater than about 8 and an atomic percent of the Nb is greater than about 9, and a magnetic recording layer on the soft magnetic underlayer.Type: GrantFiled: March 13, 2013Date of Patent: January 17, 2017Assignee: WD Media, LLCInventors: Iwao Okamoto, Debashish Tripathy, Fei Qin
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Patent number: 9472227Abstract: [Problem] An object is to provide a perpendicular magnetic recording medium that can realize both improvement in crystal orientation and refinement of crystal grain size and can achieve a higher recording density and a higher SN ratio, and a method of manufacturing the same. [Solution] A perpendicular magnetic recording medium 100 of the present invention is a perpendicular magnetic recording medium 100 having a base plate 100, and a laminate film including a first ground layer 150a provided on the base plate 100, a second ground layer 150b provided on the first ground layer 150a, and a main recording layer 160 provided on the second ground layer 150b and containing a magnetic material having a granular structure, wherein the magnetic material which constitutes the main recording layer 160 contains a CoCrPt alloy, and a material which constitutes the second ground layer 150b contains an Ru—Co oxide alloy.Type: GrantFiled: June 22, 2011Date of Patent: October 18, 2016Assignee: WD Media (Singapore) Pte. Ltd.Inventors: Hi Shin, Iwao Okamoto
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Patent number: 9431045Abstract: A magnetic media is described including a substrate, an unbalanced soft under layer (SUL), a magnetic seed layer, which may consist of one or more of NiWxCoy, NiWxCoyAlz, NiVaCob, NiVaCobAlc, NiWxVaCob, and NiWxVaFeb, and a magnetic recording layer.Type: GrantFiled: April 24, 2015Date of Patent: August 30, 2016Assignee: WD MEDIA, LLCInventors: Zhenguo Wang, Iwao Okamoto, Sy Vu, Daehoon Hong
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Patent number: 9042053Abstract: A magnetic recording medium including a substrate, and at least one magnetic layer formed on the substrate. The magnetic layer is formed from an alloy containing Cobalt, and Platinum (Pt). The magnetic layer is also formed from grain boundary segregation materials comprising Manganese Oxide and at least one of Silicon Oxide, Chromium Oxide, and Cobalt Oxide (CoO).Type: GrantFiled: June 24, 2014Date of Patent: May 26, 2015Assignee: WD Media, LLCInventors: Yang Yang, Iwao Okamoto
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Patent number: 8922936Abstract: An object of the present invention is to further improve a recording density in a magnetic disk apparatus using a shingle write system. In a magnetic disk apparatus including a magnetic disk, a recording head that writes information on the magnetic disk, and a controller that controls a writing operation of the recording head to the magnetic disk, the controller controls the writing operation such that the recording head writes information on a region including a target track and a portion of track adjacent thereto in an overlapping manner while position-shifting in a radial direction of the magnetic disk and a first writing frequency to a track on which information is last written is higher than a second writing frequency to another track.Type: GrantFiled: March 24, 2011Date of Patent: December 30, 2014Assignee: WD Media (Singapore) Pte. Ltd.Inventors: Iwao Okamoto, Chiyo Saito, Daisuke Masuda
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Publication number: 20130274350Abstract: To develop a method for producing a novel sweetener containing glucose, fructose, and psicose, which is produced from glucose liquid sugar using an isomerase and an epimerase; use of the novel sweetener as a food or drink material; and a novel sweetener capable of preventing obesity caused by the intake thereof. An isomerase and an epimerase are allowed to act on glucose liquid sugar produced in a glucose liquid sugar production plant to thereby produce D-psicose, thereby providing a novel sweetener (product) that maintains the degree and quality of sweetness of a glucose-fructose mixed solution and never causes obesity, a method for producing the same, and use of the same.Type: ApplicationFiled: March 15, 2013Publication date: October 17, 2013Inventors: Kazuhiro Okuma, Koji Yamada, Koji Tsukuda, Tetsuo Iida, Hiroshi Oga, Ken Izumori, Yoshio Tsujisaka, Tsuyoshi Shimonishi, Takako Yamada, Iwao Okamoto
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Patent number: 8559131Abstract: [Problem] A perpendicular magnetic recording medium and a magnetic disk device that are suitable for a shingle recording type are provided. [Solution] The perpendicular magnetic recording medium of the present invention is a perpendicular magnetic recording medium for a shingle recording type having a laminated film including a soft magnetic layer 13 and a main recording layer 16 formed on base 11, the soft magnetic layer 13 having a thickness found from a core width of a magnetic head for recording and reproduction with respect to the perpendicular magnetic recording medium and a track pitch narrower than the core width.Type: GrantFiled: June 15, 2011Date of Patent: October 15, 2013Assignee: WD Media (Singapore) Pte. Ltd.Inventors: Daisuke Masuda, Chiyo Saito, Junichi Horikawa, Iwao Okamoto
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Publication number: 20120162808Abstract: [Problem] A perpendicular magnetic recording medium and a magnetic disk device that are suitable for a shingle recording type are provided. [Solution] The perpendicular magnetic recording medium of the present invention is a perpendicular magnetic recording medium for a shingle recording type having a laminated film including a soft magnetic layer 13 and a main recording layer 16 formed on base 11, the soft magnetic layer 13 having a thickness found from a core width of a magnetic head for recording and reproduction with respect to the perpendicular magnetic recording medium and a track pitch narrower than the core width.Type: ApplicationFiled: June 15, 2011Publication date: June 28, 2012Applicant: WD MEDIA (SINGAPORE) PTE. LTD.Inventors: Daisuke Masuda, Chiyo Saito, Junichi Horikawa, Iwao Okamoto
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Publication number: 20120164488Abstract: [Problem] An object is to provide a perpendicular magnetic recording medium that can realize both improvement in crystal orientation and refinement of crystal grain size and can achieve a higher recording density and a higher SN ratio, and a method of manufacturing the same. [Solution] A perpendicular magnetic recording medium 100 of the present invention is a perpendicular magnetic recording medium 100 having a base plate 100, and a laminate film including a first ground layer 150a provided on the base plate 100, a second ground layer 150b provided on the first ground layer 150a, and a main recording layer 160 provided on the second ground layer 150b and containing a magnetic material having a granular structure, wherein the magnetic material which constitutes the main recording layer 160 contains a CoCrPt alloy, and a material which constitutes the second ground layer 150b contains an Ru—Co oxide alloy.Type: ApplicationFiled: June 22, 2011Publication date: June 28, 2012Applicant: WD MEDIA (SINGAPORE) PTE. LTD.Inventors: Hi SHIN, Iwao OKAMOTO
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Publication number: 20120156523Abstract: [Summary] [Problem] An object is to attain both reduction in size of magnetic particles and reduction in distance between magnetic particles to achieve a higher recording density and a higher SN ratio. [Solution] A perpendicular magnetic recording medium according to the present invention is a perpendicular magnetic recording medium having a laminate film including at least a magnetic layer on a base plate, wherein the magnetic layer includes a magnetic material having a granular structure and a non-magnetic grain boundary including an inter-ceramic compound containing Mg.Type: ApplicationFiled: June 3, 2011Publication date: June 21, 2012Applicant: WD MEDIA (SINGAPORE) PTE. LTD.Inventors: TOMOKO SEKI, IWAO OKAMOTO
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Publication number: 20120069466Abstract: An object of the present invention is to further improve a recording density in a magnetic disk apparatus using a shingle write system. In a magnetic disk apparatus including a magnetic disk, a recording head that writes information on the magnetic disk, and a controller that controls a writing operation of the recording head to the magnetic disk, the controller controls the writing operation such that the recording head writes information on a region including a target track and a portion of track adjacent thereto in an overlapping manner while position-shifting in a radial direction of the magnetic disk and a first writing frequency to a track on which information is last written is higher than a second writing frequency to another track.Type: ApplicationFiled: March 24, 2011Publication date: March 22, 2012Applicant: WD Media (Singapore) Pte. Ltd.Inventors: Iwao Okamoto, Chiyo Saito, Daisuke Masuda
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Patent number: 7927725Abstract: A magnetic recording medium for use in digital magnetic recording, which comprises a nonmagnetic substrate having deposited thereon a magnetic layer, wherein with respect to the in-plane direction, the magnetic recording layer comprises a plurality of ferromagnetic regions separated from each other by an antiferromagnetic region. A production method of the magnetic recording medium and a magnetic disc apparatus are also disclosed.Type: GrantFiled: September 8, 2008Date of Patent: April 19, 2011Assignees: Showa Denko K.K., National University Corporation Akita UniversityInventors: Shunji Ishio, Hitoshi Saito, Takashi Hasegawa, Iwao Okamoto, Naoya Yamamoto
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Publication number: 20100204346Abstract: Problem: To develop a method for producing a novel sweetener containing glucose, fructose, and psicose, which is produced from glucose liquid sugar using an isomerase and an epimerase; use of the novel sweetener as a food or drink material; and a novel sweetener capable of preventing obesity caused by the intake thereof. Means of Resolution: An isomerase and an epimerase are allowed to act on glucose liquid sugar produced in a glucose liquid sugar production plant to thereby produce D-psicose, thereby providing a novel sweetener (product) that maintains the degree and quality of sweetness of a glucose-fructose mixed solution and never causes obesity, a method for producing the same, and use of the same.Type: ApplicationFiled: May 19, 2008Publication date: August 12, 2010Applicants: MATSUTANI CHEMICAL INDUSTRY CO., LTD., NAT'L UNIVERSITY CORPORATION KAGAWA UNIVERSITY, RARE SUGAR PRODUCTION TECHNICAL RESEARCH LABS., KABUSHIKI KAISHA HAYASHIBARA SEIBUTSU KAGAKU KENKYUJOInventors: Kazuhiro Okuma, Koji Yamada, Koji Tsukuda, Tetsuo Iida, Hiroshi Oga, Ken Izumori, Yoshio Tsujisaka, Tsuyoshi Shimonishi, Takako Yamada, Iwao Okamoto
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Patent number: 7625643Abstract: A magnetic recording medium is provided with a first magnetic layer, a nonmagnetic coupling layer provided on the first magnetic layer, and a second magnetic layer provided on the nonmagnetic coupling layer. The first and second magnetic layers are exchange-coupled, and have magnetization directions which are mutually parallel in a state where no external magnetic field is applied thereto, and the first magnetic layer switches the magnetization direction thereof before the second magnetic layer in response to a recording magnetic field which switches the magnetization directions of the first and second magnetic layers.Type: GrantFiled: August 14, 2007Date of Patent: December 1, 2009Assignee: Fujitsu LimitedInventors: Hisashi Umeda, Iwao Okamoto
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Publication number: 20090161254Abstract: A magnetic recording medium for use in digital magnetic recording, which comprises a nonmagnetic substrate having deposited thereon a magnetic layer, wherein with respect to the in-plane direction, the magnetic recording layer comprises a plurality of ferromagnetic regions separated from each other by an antiferromagnetic region. A production method of the magnetic recording medium and a magnetic disc apparatus are also disclosed.Type: ApplicationFiled: September 8, 2008Publication date: June 25, 2009Applicants: FUJITSU LIMITED, NATIONAL UNIVERSITY CORPORATION AKITA UNIVERSITYInventors: Shunji Ishio, Hitoshi Saito, Takashi Hasegawa, Iwao Okamoto, Naoya Yamamoto
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Publication number: 20080285177Abstract: According to an aspect of an embodiment, a magnetic recording medium includes a substrate, and a first granular layer formed over the substrate, the first granular layer having a plurality of first magnetic particles and Si oxide separating the plurality of first magnetic particles. The magnetic recording medium further includes a second granular layer formed over the first granular layer, the second granular layer having a plurality of second magnetic particles and Ti oxide separating the plurality of second magnetic particles.Type: ApplicationFiled: April 18, 2008Publication date: November 20, 2008Applicant: FUJITSU LIMITEDInventors: Ryosaku Inamura, Isatake Kaitsu, Takuya Uzumaki, Iwao OKamoto, Akira Kikuchi
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Patent number: 7435489Abstract: A magnetic recording medium is provided with an exchange layer structure, and a magnetic layer provided on the exchange layer structure. The exchange layer structure includes a ferromagnetic layer and a nonmagnetic coupling layer provided on the ferromagnetic layer, where the ferromagnetic layer and the magnetic layer are exchange-coupled and having mutually antiparallel magnetizations. The ferromagnetic layer and the magnetic layer satisfy a relationship Hc1??Hc2?, where Hc1? denotes a dynamic coercivity of the ferromagnetic layer and Hc2? denotes a dynamic coercivity of the magnetic layer.Type: GrantFiled: March 11, 2004Date of Patent: October 14, 2008Assignee: Fujitsu LimitedInventors: Hisashi Umeda, Iwao Okamoto
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Publication number: 20080002296Abstract: A magnetic recording medium is provided with a first magnetic layer, a nonmagnetic coupling layer provided on the first magnetic layer, and a second magnetic layer provided on the nonmagnetic coupling layer. The first and second magnetic layers are exchange-coupled, and have magnetization directions which are mutually parallel in a state where no external magnetic field is applied thereto, and the first magnetic layer switches the magnetization direction thereof before the second magnetic layer in response to a recording magnetic field which switches the magnetization directions of the first and second magnetic layers.Type: ApplicationFiled: August 14, 2007Publication date: January 3, 2008Inventors: Hisashi Umeda, Iwao Okamoto
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Patent number: 7271984Abstract: A magnetic recording medium is provided with a first magnetic layer, a nonmagnetic coupling layer provided on the first magnetic layer, and a second magnetic layer provided on the nonmagnetic coupling layer. The first and second magnetic layers are exchange-coupled, and have magnetization directions which are mutually parallel in a state where no external magnetic field is applied thereto, and the first magnetic layer switches the magnetization direction thereof before the second magnetic layer in response to a recording magnetic field which switches the magnetization directions of the first and second magnetic layers.Type: GrantFiled: May 21, 2004Date of Patent: September 18, 2007Assignee: Fujitsu LimitedInventors: Hisashi Umeda, Iwao Okamoto
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Patent number: 7230079Abstract: It is intended to provide an anti-allergic agent, which efficaciously relieves symptoms accompanying an allergic disease without causing any serious side effect. This object is achieved by providing an anti-allergic agent which contains, as an effective ingredient, proteins collected from royal jelly or purified royal jelly, or royal jelly or purified royal jelly containing the proteins.Type: GrantFiled: August 26, 2003Date of Patent: June 12, 2007Inventors: Iwao Okamoto, Norie Arai, Keizo Kohno, Masashi Kurimoto, Osamu Sano