Magnetic Feature Patents (Class 428/900)
  • Patent number: 6830837
    Abstract: It is an object of the present invention to provide a high reliability magnetic storage apparatus capable of performing writing and reading back of high density information. The magnetic storage apparatus is so configured as to have a longitudinal magnetic recording medium including: a magnetic layer formed on a non-magnetic substrate via a plurality of underlayers; the magnetic layer including a lower magnetic layer containing Ru in an amount of not less than 3 at % to not more than 30 at %, and Cr in an amount of not less than 0 at % to not more than 18 at %, and further containing at least one of B or C in an amount of not less than 0 at % to not more than 20 at %, and an upper magnetic layer containing Co as a main component disposed thereon via a non-magnetic intermediate layer.
    Type: Grant
    Filed: January 17, 2002
    Date of Patent: December 14, 2004
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Tetsuya Kanbe, Hiroyuki Suzuki, Yotsuo Yahisa, Yoshiyuki Hirayama, Hidekazu Kashiwase
  • Patent number: 6828047
    Abstract: A magnetic recording medium is constructed to include a substrate, a magnetic layer made of a Co or Co-based alloy, and an underlayer disposed between the substrate and the magnetic layer. The underlayer is made of an ordered intermetallic material of FCC L12 or FCT L10 crystalline structure, so that c-axis of the magnetic layer is aligned in a predetermined direction.
    Type: Grant
    Filed: March 27, 2003
    Date of Patent: December 7, 2004
    Assignee: Fujitsu Limited
    Inventors: E. Noel Abarra, Iwao Okamoto
  • Patent number: 6827968
    Abstract: A process for producing a magnetic recording medium is provided, the medium being formed from a non-magnetic flexible support, a non-magnetic layer comprising a non-magnetic powder and a binder, and a magnetic layer comprising a ferromagnetic powder and a binder. The non-magnetic layer is provided on top of the support, the magnetic layer is provided on top of the non-magnetic layer, and the non-magnetic powder includes two or more types of non-magnetic powder, including carbon black and a non-magnetic powder other than carbon black. The process includes a step of separately dispersing a non-magnetic liquid A that includes a binder and a non-magnetic powder other than carbon black, and a non-magnetic liquid B that includes carbon black and a binder, and a step of stirring and mixing the non-magnetic liquid A and the non-magnetic liquid B to prepare a non-magnetic coating solution.
    Type: Grant
    Filed: June 24, 2003
    Date of Patent: December 7, 2004
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Koji Naoe
  • Patent number: 6828004
    Abstract: Connected fastening members and method for mold-in articles. The connected fastening members include a plurality of mold-in fastening members each having a substrate and a predetermined number of engaging elements formed on a first or front surface of the substrate. The mold-in fastening members are connected with each other by a connecting member that is disposed on a second or the back surface thereof. Using the connected fastening members, a plurality of the fastening members can be easily fit to a recessed portion of a mold in a single operation, resulting in improved working efficiency.
    Type: Grant
    Filed: October 4, 2002
    Date of Patent: December 7, 2004
    Assignee: Kuraray Co., Ltd.
    Inventors: Hiroshi Itoh, Kunihiko Shimamura, Tooru Tanokura, Shiro Ogawa, Takashi Saeki
  • Patent number: 6824896
    Abstract: A magnetic media structure 200 deposited on glass substrates without a NiP layer having oriented media (ORMRT>1), high coercivity and high SMNR is presented. This media will significantly reduce the cost of making high quality media on glass substrates by eliminating the cost associated with additional steps of depositing a NiP layer and texturing that layer. First glass substrates are mechanically textured to have a surface roughness of about 1 Å to about 12 Å. The first layer of the magnetic structure contains Cr and Ti with a Ti content of 27 to 63 atomic percentage. The second layer contains Co and Ti with a Ti content of 43 to 55 atomic percentage. The third layer is a Cr-alloy layer wherein the alloy is an element chosen from W, Mo, V, Si, Ti, Mn, Ru, B, Nb, Ta, Zr, and Pt. The fourth layer is Co58Cr37Pt5 and the fifth layer is Co61Cr15Pt12B12. Finally, the protective overcoat is typically a hard material that contains hydrogenated carbon.
    Type: Grant
    Filed: December 31, 2002
    Date of Patent: November 30, 2004
    Assignee: Seagate Technology LLC
    Inventors: Li-Lien Lee, Samuel Dacke Harkness, Kien Vinh Hua, Eric Steck Freeman
  • Patent number: 6821593
    Abstract: A mounting assembly for attaching lightweight articles to surfaces incorporating an article fixation region opposite and distal to a poly-fastening region. A poly-fastening region includes at least one selective adhesive region adjacent to at least one magnetic region. In one embodiment, a selective adhesive region includes an adhesive layer covering a magnetic region comprising a magnet with sufficient magnetic strength to magnetically attach an article to a surface. In another embodiment, a selective adhesive region includes an adhesive surface of an adhesive layer adjacent to and co-planar with a magnetic surface of a magnetic region. In an alternative embodiment, a selective adhesive region is capable of variable planar alignment with respect to an adjacent magnetic surface. The selective adhesive region of a mounting assembly has sufficient strength to adhesively attach an article and mounting assembly to a surface.
    Type: Grant
    Filed: January 6, 2003
    Date of Patent: November 23, 2004
    Inventors: Roberta Maggio, Anthony Maggio
  • Patent number: 6821654
    Abstract: High SNR longitudinal magnetic recording media with improved bit error rate are fabricated using a CrMoTa underlayer for uniform magnetic grain size. Embodiments include magnetic recording media comprising a composite underlayer of Cr and Cr100-x-yMoxTay, wherein x is 1 to 20 and y is 1 to 6, and a magnetic layer having a uniform grain size with a standard deviation no greater than 0.4.
    Type: Grant
    Filed: October 15, 2002
    Date of Patent: November 23, 2004
    Assignee: Seagate Technology LLC
    Inventor: Mariana Rodica Munteanu
  • Patent number: 6821652
    Abstract: A magnetic recording medium is constructed to include at least one exchange layer structure, and a magnetic layer formed on the exchange layer structure, where the exchange layer structure comprises a ferromagnetic layer, and a non-magnetic coupling layer provided on the ferromagnetic layer and under the magnetic layer. The ferromagnetic layer and the magnetic layer have antiparallel magnetizations. The non-magnetic coupling layer is made of a Ru-M3 alloy, where M3 is an added element or alloy, and a lattice mismatch between the non-magnetic coupling layer and the magnetic layer and the ferromagnetic layer respectively disposed above and below the non-magnetic coupling layer is adjusted to approximately 6% or less by addition of M3.
    Type: Grant
    Filed: June 6, 2000
    Date of Patent: November 23, 2004
    Assignee: Fujitsu Limited
    Inventors: Iwao Okamoto, E. Noel Abarra, Yoshifumi Mizoshita
  • Patent number: 6822831
    Abstract: An object of the present invention is to provide a recording head having a magnetic pole simultaneously possessing a high saturation magnetic flux density, a high permeability and a high electric resistivity, and the magnetic pole of the recording head is a polycrystalline film comprising Fe whose content is not less than 57.5 atomic % and not more than 94.5 atomic %; one or more kinds of elements selected from the element group of Al, B, Ga, Si, Ge, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W and Rh, whose whole content is not less than 1 atomic % and not more than 15 atomic %; N whose content is not less than 0.5 atomic % and not more than 10 atomic %; and O whose content is not less than 1.5 atomic % and not more than 22.5 atomic %.
    Type: Grant
    Filed: February 12, 2002
    Date of Patent: November 23, 2004
    Assignee: Fujitsu Limited
    Inventors: Shoji Ikeda, Yuji Uehara, Ikuya Tagawa, Naoki Takeguchi, Masahiro Kakehi
  • Patent number: 6818299
    Abstract: Multilayered magnetic pigment flakes and foils are provided. The pigment flakes can have a symmetrical coating structure on opposing sides of a magnetic core, or can be formed with encapsulating coatings around the magnetic core. The magnetic core can be a magnetic layer between reflector or dielectric layers, a dielectric layer between magnetic layers, or only a magnetic layer. Some embodiments of the pigment flakes and foils exhibit a discrete color shift so as to have distinct colors at differing angles of incident light or viewing. The pigment flakes can be interspersed into liquid media such as paints or inks to produce colorant compositions for subsequent application to objects or papers. The foils can be laminated to various objects or can be formed on a carrier substrate.
    Type: Grant
    Filed: February 7, 2003
    Date of Patent: November 16, 2004
    Assignee: Flex Products, Inc.
    Inventors: Roger W. Phillips, Charlotte R. LaGallee, Charles T. Markantes, Paul G. Coombs
  • Patent number: 6818330
    Abstract: A perpendicular magnetic recording medium with antiferromagnetic coupling in a soft magnetic underlayer. The soft magnetic underlayer includes a first magnetic soft layer, a first interface layer on the first magnetic soft layer, a second magnetic soft layer, a second interface layer on the second magnetic soft layer, and a non-magnetic coupling layer between the first interface layer and the second interface layer. The first and second magnetic soft layers are antiferromagnetically exchange coupled to one another through the non-magnetic coupling layer, wherein the first and second interface layers increase the exchange coupling between the first and second magnetic soft layers.
    Type: Grant
    Filed: August 24, 2001
    Date of Patent: November 16, 2004
    Assignee: Seagate Technology LLC
    Inventors: Alexander M. Shukh, Eric W. Singleton, Sakhrat Khizroev, Dmitri Litvinov
  • Patent number: 6818331
    Abstract: A magnetic recording medium having a non-magnetic substrate; an orientation-regulating layer for regulating the crystal orientation of a layer provided directly thereon; a perpendicular magnetic layer in which easy-magnetization axes are oriented generally perpendicular to the substrate; and a protective layer is disclosed. The perpendicular magnetic layer is formed from a material containing Co as a primary component and at least Cr, Pt, and Nd. A process to produce the magnetic recording medium and a magnetic recording and reproducing apparatus are also disclosed.
    Type: Grant
    Filed: August 28, 2002
    Date of Patent: November 16, 2004
    Assignee: Showa Denko Kabushiki Kaisha
    Inventors: Akira Sakawaki, Kenji Shimizu, Hiro Mochizuki, Masato Kokubu, Hui Yang, Masakazu Kobayashi, Hiroshi Sakai
  • Patent number: 6818298
    Abstract: A magnetic recording medium including a non-magnetic substrate, a back coat, a lower layer, and a magnetic upper layer. The substrate defines a front side and back side, with the back coat being formed on the back side. The lower layer is disposed over the front side of the substrate and includes a primary powder material and conductive carbon black material dispersed in a binder. The primary lower layer powder material comprises particles having a coercivity of less than 300 Oe coated with an electroconductive material. The magnetic upper layer is disposed over the lower layer and includes a magnetic powder dispersed in a binder.
    Type: Grant
    Filed: October 1, 2002
    Date of Patent: November 16, 2004
    Assignees: Imation Corp., Quantegy, Inc.
    Inventors: David C. Lowery, Ryosuke Isobe
  • Patent number: 6815098
    Abstract: A magnetic recording medium comprises, on a substrate, a soft magnetic layer, a first seed layer, a second seed layer, and a recording layer having an artificial lattice structure. The first seed layer contains oxide of Fe. The second seed layer contains one of Pd and Pt, Si, and N. The magnetic exchange coupling force in the in-plane direction of the recording layer is weakened by the first seed layer and the second seed layer. Accordingly, minute recording magnetic domains can be formed in the recording layer, and the magnetization transition area is distinct as well. Even when information is recorded at a high density, the information can be reproduced with low noise. A magnetic storage apparatus, which is provided with such a magnetic recording medium, makes it possible to achieve an areal recording density of 150 gigabits/square inch.
    Type: Grant
    Filed: April 11, 2003
    Date of Patent: November 9, 2004
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Satoshi Matsunuma, Akira Yano, Tsuyoshi Onuma, Takanobu Takayama, Harumi Hieida, Kouichirou Wakabayashi
  • Patent number: 6815097
    Abstract: A magnetic recording medium comprising a non-magnetic substrate having thereon a non-magnetic underlayer, a magnetic recording layer, a soft magnetic layer and a protective layer, wherein the coercivity is 2,500 Oe or more and the thickness of the soft magnetic layer is from 5 to 50 Å.
    Type: Grant
    Filed: February 21, 2002
    Date of Patent: November 9, 2004
    Assignee: Showa Denko K.K.
    Inventors: Toshihiko Yoshikawa, Akira Sakawaki, Hiroshi Sakai
  • Publication number: 20040214008
    Abstract: A flexible noise and vibration damping laminate attachable to a metallic substrate having a first and second constraining layers sandwiching a first viscoelastic layer, a second viscoelastic layer in abutting relationship with the second constraining layer, and a heat activated adhesive disposed on the second viscoelastic layer, all of which are respectively superimposed to the respective adjacent layer.
    Type: Application
    Filed: April 25, 2003
    Publication date: October 28, 2004
    Inventors: Scott R. Dobrusky, John M. Hatkow, Harold H. Levine
  • Publication number: 20040214496
    Abstract: A compound material at least comprises a pair of overlapped high heat conductive layer and electromagnetic interference (EMI) shielding layer. The EMI shielding layer includes a high heat conductive sub-layer and a plurality of EMI shielding blocks thereby forming an EMI shielding net and a heat conducting track with the cooperation of the overlapped heat conductive layer in the meantime. The compound material further comprises a second EMI shielding layer overlapped on the side of the heat conductive layer which is opposite to said EMI shielding layer and having a plurality of EMI shielding blocks, which are arranged in a similar as and are staggered from the EMI shielding blocks of said EMI shielding layer in the overlapped or vertical direction thereof.
    Type: Application
    Filed: March 31, 2004
    Publication date: October 28, 2004
    Applicant: CATERON CORP.
    Inventor: Ching-Lung Yang
  • Patent number: 6808830
    Abstract: The present invention is made to provide a magnetic recording medium, which exhibits excellent magnetic characteristics, such as thermal stability and excellent glide height characteristics, and can be easily produced. The basic constitution is a non-magnetic substrate on which is formed a non-magnetic undercoat layer, a magnetic layer, and a protective layer, wherein the non-magnetic undercoat layer has a bcc structure; an orientation-adjustment layer for causing the non-magnetic undercoat layer to have a predominant orientation plane of (200) is formed between the non-magnetic substrate and the non-magnetic undercoat layer; the magnetic layer has a crystal structure in which columnar fine crystal grains are inclined in the circumferential direction; and the ratio of the coercive force in the circumferential direction of the magnetic layer 4 Hcc to the coercive force in the radial direction Hcr, i.e., Hcc/Hcr, is more than 1.
    Type: Grant
    Filed: December 27, 2002
    Date of Patent: October 26, 2004
    Assignee: Showa Denko K.K.
    Inventors: Akira Sakawaki, Hiroshi Sakai
  • Patent number: 6805980
    Abstract: Refractory metal layers 2, 4, 6, 8, and 10, and rare earth alloy magnetic layers 3, 5, 7, 9, 11, and 12 are alternately deposited, so as to form a multilayer structure including four or more layers on a substrate. The refractory metal layers 2, 4, 6, 8, and 10 are formed from at least one kind of material selected from a group consisting of Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, and W, and each has a thickness of not less than 5 nm nor more than 50 nm. The rare earth alloy magnetic layers 3, 5, 7, 9, 11, and 12 have tetragonal R2Fe14B (R is Nd and/or Pr) as a primary constituent phase, and each has a thickness of not less than 50 nm nor more than 500 nm.
    Type: Grant
    Filed: October 22, 2001
    Date of Patent: October 19, 2004
    Assignee: Neomax Co., Ltd.
    Inventor: Minoru Uehara
  • Patent number: 6805981
    Abstract: A perpendicular magnetic recording medium comprising a layer exhibiting a super paramagnetism is used as the underlying film to enable the recording medium to achieve a high density recording with a low noise.
    Type: Grant
    Filed: July 12, 2001
    Date of Patent: October 19, 2004
    Assignees: Kabushiki Kaisha Toshiba, Showa Denko K.K.
    Inventors: Hideo Ogiwara, Takashi Hikosaka, Soichi Oikawa, Hiroshi Sakai, Kenji Shimizu
  • Patent number: 6805966
    Abstract: A dual-sided stamper/imprinter for simultaneously forming magnetic transition patterns in spaced-apart first and second layers of magnetic material by contact printing comprises a mechanically hard, substantially rigid magnetic material having high saturation magnetization and high permeability and including first and second oppositely facing imprinting surfaces, wherein each of the imprinting surfaced has a topographical pattern formed therein comprising a patterned plurality of spaced-apart recesses with a plurality of non-recessed areas therebetween, each topographical pattern corresponding to a magnetic transition pattern to be formed in a respective layer of magnetic material. Also disclosed is a method for manufacturing dual-sided stampers/imprinters.
    Type: Grant
    Filed: February 11, 2003
    Date of Patent: October 19, 2004
    Assignee: Seagate Technology LLC
    Inventors: Christopher Formato, Jing Gui
  • Patent number: 6803118
    Abstract: A semi-hard magnetic alloy for activation strips in magnetic anti-theft security systems is disclosed that contains 8 to 25 weight % Ni, 1.0 to 4.5 weight % Al, 0.5 to 3 weight % Ti and the balance iron.
    Type: Grant
    Filed: September 26, 2003
    Date of Patent: October 12, 2004
    Assignee: Vacuumschmelze GmbH
    Inventors: Hartwin Weber, Gernot Hausch, Ottmar Roth
  • Patent number: 6803131
    Abstract: Fine projections on a magnetic layer surface are controlled so as to reduce a media noise and improve C/Nmedia characteristic. A magnetic recording medium allows reproduction through a MR head or a GMR head. The magnetic layer on a main surface of a non-magnetic base has a coercive force of 80 KA/m or more and 180 KA/m or less. Assuming that a height of the fine projections is h and a diameter of the fine projections at a half-height h/2 is &phgr;h/2, 99% of the fine projections having a height not less than 10 nm satisfy a relationship as expressed by 100 nm≧&phgr;h/2≧40 nm.
    Type: Grant
    Filed: September 6, 2002
    Date of Patent: October 12, 2004
    Assignee: Sony Corporation
    Inventors: Naoki Ikeda, Seiichi Onodera
  • Patent number: 6797415
    Abstract: A track width defining layer for defining a write track width of a thin-film magnetic head is made of a CoNiFe film formed through electroplating. The CoNiFe film contains 60 to 75 weight % cobalt, 10 to 20 weight % nickel, and 10 to 20 weight % iron, and has a crystal structure that is a mixture of a body-centered cubic structure phase and a face-centered cubic structure phase, in which Ib/If falls within the range of 0.3 to 0.7 inclusive where Ib represents the intensity of an X-ray diffracted from a (110)-plane of the body-centered cubic structure and If represents the intensity of an X-ray diffracted from a (111)-plane of the face-centered cubic structure. The pH of a plating bath for forming the CoNiFe film through electroplating is adjusted to 3.0 to 4.0 inclusive.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: September 28, 2004
    Assignee: TDK Corporation
    Inventors: Atsushi Yamaguchi, Seiji Yari, Tetsuya Mino, Shuichi Okawa, Shigeru Ichihara
  • Patent number: 6794063
    Abstract: The present invention provides a thin film magnetic head having sufficient recording performance on a recording medium imparted with a large coercive force. According to the present invention, a plated magnetic thin film can be obtained in which a crystal grain size is modulated in a film thickness direction and a coercive force is reduced. Further, according to the present invention, even for a composition area indicating a high saturation magnetic flux density in which, conventionally, soft magnetic properties could not be obtained, magnetic film having an excellent soft magnetic property can be manufactured.
    Type: Grant
    Filed: May 24, 2002
    Date of Patent: September 21, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Yasuyuki Okada, Kazue Kudo, Hiroyuki Hoshiya
  • Patent number: 6794028
    Abstract: A perpendicular magnetic recording medium has a granular magnetic layer and a nonmagnetic underlayer of a metal or an alloy having a hexagonal closest-packed (hcp) crystal structure. A seed layer of a metal or an alloy of a face-centered cubic (fcc) crystal structure is provided under the nonmagnetic underlayer. Such a perpendicular magnetic recording medium exhibits excellent magnetic characteristics even when the thickness of the underlayer or the total thickness of the underlayer and the seed layer is very thin. Excellent magnetic characteristics can be obtained even when of the substrate is not preheated. Accordingly, a nonmagnetic substrate, such as a plastic resin can be employed to reduce the manufacturing cost.
    Type: Grant
    Filed: August 23, 2002
    Date of Patent: September 21, 2004
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Hiroyuki Uwazumi, Yasushi Sakai, Tadaaki Oikawa, Miyabi Nakamura
  • Patent number: 6790509
    Abstract: A substrate for an information recording medium, wherein the period of microwaviness is 2 &mgr;m to 4 mm, and if we let wa be the maximum height of this microwaviness and Rmax be the maximum height measured by atomic force microscope, the main surface of the substrate has a wa of no more than 5 nm and an Rmax of no more than 12 nm, provided that wa is the difference between the highest and lowest points on a measurement curve of all measured points in a measurement area.
    Type: Grant
    Filed: October 4, 2001
    Date of Patent: September 14, 2004
    Assignee: Hoya Corporation
    Inventors: Tomotaka Yokoyama, Takemi Miyamoto, Hiroshi Tomiyasu, Kouji Takahashi
  • Patent number: 6790541
    Abstract: An exchange coupling film has an antiferromagnetic layer made of an antiferromagnetic material containing an element X and Mn, where the element X is selected from the group of elements consisting of Pt, Pd, Ir, Rh, Ru, and Os, and combinations thereof. The antiferromagnetic layer has a region in which the ratio of the atomic percent of the element X to Mn increases towards said ferromagnetic layer. The crystalline structure of at least part of said antiferromagnetic layer has a CuAu—I type face-centered square ordered lattice.
    Type: Grant
    Filed: April 11, 2001
    Date of Patent: September 14, 2004
    Assignee: Alps Electric Co., Ltd.
    Inventors: Masamichi Saito, Naoya Hasegawa, Yosuke Ide, Kenichi Tanaka
  • Patent number: 6787251
    Abstract: A bi-crystal magnetic recording medium, i.e., medium with Cr(200) and Co(11.0) orientations, having a CrW-containing underlayer in which the W content increases for improved lattice matching with a Co-alloy magnetic layer has high coercivity, high SMNR and high areal recording density.
    Type: Grant
    Filed: August 5, 2002
    Date of Patent: September 7, 2004
    Assignee: Seagate Technology LLC
    Inventors: Zhong Stella Wu, Qixu David Chen, Samuel Dacke Harkness
  • Patent number: 6787252
    Abstract: A perpendicular magnetic recording medium without shift or loss of written signals even in a case of a high recording density in a rare earth-transition metal alloy amorphous film, and where productivity is excellent. The perpendicular magnetic recording medium includes a soft magnetic under layer, an intermediate layer, a magnetic recording layer including a rare earth-transition metal alloy amorphous film and at least one of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, B, Al, C and Si or a boride or carbide uniformly dispersed in the rare earth-transition metal alloy amorphous film, a protective layer, a liquid lubricant layer, and a nonmagnetic substrate. The soft magnetic under layer, the intermediate layer, the magnetic recording layer, and the protective layer are built up in a predetermined order on the nonmagnetic substrate.
    Type: Grant
    Filed: August 26, 2002
    Date of Patent: September 7, 2004
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Yasushi Sakai, Sadayuki Watanabe
  • Patent number: 6783889
    Abstract: The present invention provides a polyester film, which is composed of a polyester resin and a polyimide resin, having superior oligomer-restraining property and dimensional stability. This polyester film also has improved surface conditions, that is, has a reduced number of projections on the surface, and hence, the polyester film shows superior electromagnetic conversion characteristics when used for magnetic recording media. In particular, this polyester film is effectively used for high-density magnetic recording media. This film is composed of a polyester resin and a thermoplastic resin other than a polyester resin, and has a number H1 of coarse projections 0.28 &mgr;m or more in height of 0 to 100/100 cm2 on at least one surface of the polyester film and a number H2 of coarse projections 0.56 &mgr;m or more in height of 0 to 10/100 cm2 on the same surface.
    Type: Grant
    Filed: December 5, 2001
    Date of Patent: August 31, 2004
    Assignee: Toray Industries, Inc.
    Inventors: Akira Kubota, Kenichi Eto, Yukari Nakamori, Tetsuya Tsunekawa
  • Patent number: 6783874
    Abstract: First electrode layers are formed on second antiferromagnetic layers, and in a step separate from the above, second electrode layers are formed above internal end surfaces of the second antiferromagnetic layers and the first electrode layers and parts of the upper surface of the multilayer film with an additional film provided therebetween. Since the first and the second electrode layers are formed separately, it is not necessary to perform mask alignment twice, and hence an overlap structure can be precisely formed in which the thickness of the second electrode layer at the left side is equivalent to that at the right side.
    Type: Grant
    Filed: April 2, 2003
    Date of Patent: August 31, 2004
    Assignee: Alps Electric Co., Ltd.
    Inventors: Naoya Hasegawa, Eiji Umetsu, Naohiro Ishibashi, Masahiro Oshima
  • Publication number: 20040166377
    Abstract: A perpendicular magnetic recording medium having a substrate, a seedlayer on the substrate and a magnetic underlayer on the seedlayer, the magnetic underlayer having an easy axis of magnetization substantially directed in a radial or transverse direction, and a process for manufacturing the perpendicular magnetic recording medium are disclosed.
    Type: Application
    Filed: December 8, 2003
    Publication date: August 26, 2004
    Inventors: Chung-Hee Chang, Rajiv Y. Ranjan
  • Patent number: 6780530
    Abstract: A magnetic material includes a main component expressed by a general formula CoNiFeX, wherein X is at least one element selected from the group consisting of Cr, Ti, V, Ru, Rh, Pd, Os, Ir and Pt, and wherein weight percentages a, b, c and d of Co, Ni, Fe and X contents, respectively, in the main component are such that 40%≦a≦10%, 5%≦b≦20%, 10%≦c≦30%, and 0%<d≦10%.
    Type: Grant
    Filed: May 5, 2003
    Date of Patent: August 24, 2004
    Assignee: NEC Corporation
    Inventors: Mikiko Saito, Nobuyuki Ishiwata, Tsutomu Ishi, Hiroaki Honjo, Tamaki Toba, Shinsaku Saito, Yoshihiro Nonaka
  • Patent number: 6777112
    Abstract: A magnetic recording medium having increased thermal stability and signal-to-medium noise ratio (SMNR), comprising a layer stack including, in sequence: (a) a continuous ferromagnetic layer; (b) a non-magnetic spacer layer; and (c) a discontinuous ferromagnetic layer; wherein the continuous ferromagnetic layer (a) and the discontinuous ferromagnetic layer (c) are ferromagnetically or anti-ferromagnetically coupled together across the non-magnetic spacer layer.
    Type: Grant
    Filed: October 9, 2001
    Date of Patent: August 17, 2004
    Assignee: Seagate Technology LLC
    Inventors: Erol Girt, Hans Jürgen Richter, Samuel D. Harkness
  • Patent number: 6777077
    Abstract: A perpendicular magnetic recording medium is provided. The perpendicular magnetic recording medium has an underlayer for leading perpendicular orientation of a perpendicular magnetic recording layer, stacked between a substrate and the perpendicular magnetic recording layer, and thickness of the perpendicular magnetic recording layer is controlled within the range of 5-40 nm to have a negative nucleation field.
    Type: Grant
    Filed: January 8, 2002
    Date of Patent: August 17, 2004
    Assignees: Samsung Electronics Co., Ltd., Korea Advanced Institute of Science and Technology
    Inventors: Kyung-jin Lee, Taek-dong Lee, In-seon Lee, Min-sik Hwang
  • Patent number: 6773812
    Abstract: Microspheres are constructed using magnetic particles. Hybrid microspheres are constructed using fluorescent or luminescent microspheres and magnetic nanoparticles. Reactive moieties on the surface of the resultant particles can be used for attachment of biologically active molecules, thus allowing selective separations and analytical assays to be performed. Distinguishable subsets of microspheres can be constructed based on fluorescent intensities, and separations can be affected based on variable degree of magnetic content.
    Type: Grant
    Filed: April 6, 2001
    Date of Patent: August 10, 2004
    Assignee: Luminex Corporation
    Inventors: Don J. Chandler, Michael A. Herren
  • Patent number: 6773823
    Abstract: By utilizing the sequential synthesis afforded reverse micelles, nanocomposite materials can be synthesized which have a diamagnetic core surrounded by a thin shell of ferromagnetic material passivated with a second shell of a diamagnet. Using gold as the diamagnetic material and iron as the ferromagnetic material, nanocomposites can be synthesized where there is a thin layer of the magnetic material, which is passivated and protected from oxidation. In this case, all of the spins of the magnetic layer lie within the surface of the particle.
    Type: Grant
    Filed: April 9, 2001
    Date of Patent: August 10, 2004
    Assignee: University of New Orleans Research and Technology Foundation, Inc.
    Inventors: Charles J. O'Connor, Everett E. Carpenter, Jessica Ann Sims
  • Patent number: 6773834
    Abstract: A laminated magnetic recording medium for data storage has an antiferromagnetically-coupled (AFC) layer and a single ferromagnetic layer spaced apart by a nonferromagnetic spacer layer. The AFC layer is formed as two ferromagnetic films antiferromagnetically coupled together across an antiferromagnetically coupling film that has a composition and thickness to induce antiferromagnetic coupling. In each of the two remanent magnetic states, the magnetic moments of the two antiferromagnetically-coupled films in the AFC layer are oriented antiparallel, and the magnetic moment of the single ferromagnetic layer and the greater-moment ferromagnetic film of the AFC layer are oriented parallel. The nonferromagnetic spacer layer between the AFC layer and the single ferromagnetic layer has a composition and thickness to prevent antiferromagnetic exchange coupling. The laminated medium has improved thermal stability and reduced intrinsic media noise.
    Type: Grant
    Filed: January 29, 2002
    Date of Patent: August 10, 2004
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hoa Van Do, Eric Edward Fullerton, David Thomas Margulies, Hal Jervis Rosen
  • Patent number: 6773833
    Abstract: A magnetic storage medium includes first and second magnetic layers provided on a support substrate such that the first and second magnetic layers have respective first and second magnetizations in an anti-parallel relationship in a state no substantial writing magnetic field is applied. The first and second magnetizations are changed to a parallel relationship when a writing magnetic field is applied to the magnetic storage medium, and the first and second magnetizations are changed to the anti-parallel relationship as a result of a magnetic reversal caused in the second magnetic layer with diminishing of the writing magnetic field. The reversal is caused as a result of the action of a reversing magnetic field that dominates before the writing magnetic field is diminished and becomes zero.
    Type: Grant
    Filed: March 15, 2001
    Date of Patent: August 10, 2004
    Assignee: Fujitsu Limited
    Inventors: Akihiro Inomata, E. Noel Abarra, B. Ramamurthy Acharya
  • Patent number: 6774066
    Abstract: A composite structural reinforcement device to be applied to structural members by wrapping in successive overlying layers includes a body formed of a first ply of resin impregnated high tensile strength material, a second ply of resin impregnated high tensile strength material, a magnetically detectable ply disposed and bonded between the first and second plies, an interlock means for mechanically interlocking successive layers as the device is applied to a structural member, and an alignment means for aligning successive layers of the device in overlying relation. Various alternative embodiments and various combinations of features are disclosed.
    Type: Grant
    Filed: June 15, 2000
    Date of Patent: August 10, 2004
    Inventors: James M. Souza, Glenn Davis, Billy H. Davidson
  • Publication number: 20040150285
    Abstract: A high efficiency electric motor has a generally polyhedrally shaped bulk amorphous metal magnetic component in which a plurality of layers of amorphous metal strips are laminated together adhesively to form a generally three-dimensional part having the shape of a polyhedron. The bulk amorphous metal magnetic component may include an arcuate surface, and preferably includes two arcuate surfaces that are disposed opposite to each other. The magnetic component is operable at frequencies ranging from about 50 Hz to about 20,000 Hz. When the motor is operated at an excitation frequency “f” to a peak induction level Bmax, the component exhibits a core-loss less than about “L” wherein L is given by the formula L=0.005 f(Bmax)1.5+0.000012 f1.5(Bmax)1.6, said core loss, said excitation frequency and said peak induction level being measured in watts per kilogram, hertz, and teslas, respectively.
    Type: Application
    Filed: February 3, 2003
    Publication date: August 5, 2004
    Inventors: Nicholas J. Decristofaro, Gordon E. Fish, Scott M. Lindquist, Carl E. Kroger
  • Patent number: 6770389
    Abstract: To provide an improved perpendicular magnetic recording medium suitable for high density magnetic recording. In a perpendicular magnetic recording medium comprising a perpendicular magnetic layer and protective layer provided on a non-magnetic substrate via a soft magnetic backlayer, a polycrystalline MgO film is inserted between the soft magnetic backlayer and perpendicular magnetic layer.
    Type: Grant
    Filed: April 2, 2003
    Date of Patent: August 3, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Masaaki Futamoto, Yoshiyuki Hirayama, Yukio Honda, Atsushi Kikukawa
  • Patent number: 6770386
    Abstract: A magnetic recording medium with a high recording density has a first ferromagnetic layer, a non-magnetic layer, and a second ferromagnetic layer successively deposited as the recording layer on a non-magnetic substrate. The recording layer is heated in concentric circular shapes to divide it into regions in which the magnetic interactions between the ferromagnetic layers exhibit ferromagnetism and regions that exhibit anti-ferromagnetism. The ferromagnetic regions are used for recording tracks, and the anti-ferromagnetic regions function as guard bands. In this manner track density is increased without roughening the surface of the recording medium.
    Type: Grant
    Filed: September 1, 2000
    Date of Patent: August 3, 2004
    Assignee: Fujitsu Limited
    Inventors: Yoshiaki Hara, Takahiko Sugawara, Yutaka Shimizu, Takuya Uzumaki, Atsushi Tanaka
  • Patent number: 6767610
    Abstract: A magnetic tape includes: a back coating layer containing a carbon black; a support; a non-magnetic layer containing a non-magnetic powder and a binder, which is substantially non-magnetic; and a magnetic layer containing a ferromagnetic powder and a binder, in this order, wherein the magnetic tape is a magnetic tape for recording a signal with a 10 to 100 Mbit/cm2 surface recording density; the magnetic tape has a temperature expansion coefficient in a width direction thereof of a 0.0015%/° C. or less, a humidity expansion coefficient of 0.0015%/% RH or less, an offset yield strength in a longitudinal direction thereof of 10N or more, a rupture strength of 30 N or more; and the support has a center plane average roughness on a coating surface side of the magnetic layer of 1.0 nm or less, a center plane average roughness on a coating surface side of the back coating layer of 3.0 to 9.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: July 27, 2004
    Assignee: Fuji Photo Film Co., Inc.
    Inventors: Masatoshi Takahashi, Minoru Sueki, Toshiyuki Kitahara
  • Publication number: 20040142198
    Abstract: A kinetically sprayed magnetostrictive/magnetic material, comprising: magnetostriction particles; magnetic particles with coercivity; a ductile matrix for bonding the magnetostriction particles and magnetic particles with coercivity together; wherein an applied magnetic field will align the magnetic particles with coercivity and subsequently the magnetostriction particles such that the magnetostrictive material will produce a detectable change in the magnetostrictive/magnetic material when placed under an applied stress.
    Type: Application
    Filed: January 21, 2003
    Publication date: July 22, 2004
    Inventor: Thomas Hubert Van Steenkiste
  • Patent number: 6764721
    Abstract: A perpendicular magnetic recording medium is formed of a soft magnetic layer, an anti-ferromagnetic layer, a magnetic recording layer, a protective layer, and a liquid lubricant layer deposited in that order on a non-magnetic substrate. The anti-ferromagnetic layer is a Mn alloy containing at least Co at 10 atomic % or greater and 50 atomic % or less or a Mn alloy containing at least Ir at 10 atomic % or greater and 30 atomic % or less. A radial magnetic field is applied during formation of the anti-ferromagnetic layer and the soft magnetic layer. Exchange coupling with the anti-ferromagnetic layer controls magnetic domain walls of the soft magnetic layer. The need for heat treatment after film formation is eliminated.
    Type: Grant
    Filed: October 20, 2003
    Date of Patent: July 20, 2004
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Hiroyuki Uwazumi, Yasushi Sakai, Toyoji Ataka
  • Patent number: 6764732
    Abstract: A magnet receptive medium comprises a sheet having a first surface, a second surface, and an interior between the first surface and the second surface. At least one pathway between at least one of the surfaces and through the interior is formed. Magnetic particles of a predetermined size sufficient to pass through the pathways exist in such pathways. A binding agent may bind the particles to the interior.
    Type: Grant
    Filed: July 11, 2002
    Date of Patent: July 20, 2004
    Assignee: Magna Paper LLC
    Inventors: Paul Stefanutti, John Willwerth, Dayton J. Deetz
  • Patent number: 6761983
    Abstract: The magnetic information recording medium includes a backing layer containing Fe and C as its main ingredients, having a substantially amorphous structure, and having an easy axis of magnetization in an in-plane direction, and a magnetic layer having an easy axis of magnetization in a vertical direction and recording information.
    Type: Grant
    Filed: June 4, 2002
    Date of Patent: July 13, 2004
    Assignee: Fujitsu Limited
    Inventor: Takeshi Morikawa
  • Patent number: RE38587
    Abstract: The present invention relates to a magnetic recording medium for use in an external memory device of an information processing apparatus etc., and an object thereof is to reduce noise, achieve high coercive force, and use the substance as a magnetic recording medium for detecting signals in a magnetoresistance head. In the magnetic recording medium comprising the magnetic recording layer 25 including ferromagnetic grains 22 and a nonmagnetic substance 23, the improvement in structure comprises that the ferromagnetic grains 22 are formed to have respectively an average grain diameter of 50 nm or less and not to be overlapped in the film thickness direction and to be isolated in the direction along a layer surface, and that a product of residual magnetization and a film thickness of the magnetic recording layer 25 is less than or equal to 150 Gauss•&mgr;m.
    Type: Grant
    Filed: June 30, 2000
    Date of Patent: September 14, 2004
    Assignee: Fujitsu Limited
    Inventors: Isatake Kaitsu, Iwao Okamoto, Masayoshi Shinohara