Patents Examined by Louis Falasco
  • Patent number: 9003834
    Abstract: The present invention provides a glass substrate for magnetic disk in which surface irregularity of a principal surface is suppressed and a method for efficiently manufacturing a glass substrate for magnetic disk. The method includes the steps of: forming a sheet glass material by performing press forming to molten glass, a principal surface of the sheet glass material having target flatness for the glass substrate for magnetic disk, the sheet glass material having a surface shape to be ground using a grinding abrasive grain; grinding the sheet glass material using a fixed abrasive grain; and polishing the sheet glass material using a loose abrasive grain, the sheet glass material having surface irregularity of the principal surface ground using the fixed abrasive grain.
    Type: Grant
    Filed: December 27, 2010
    Date of Patent: April 14, 2015
    Assignee: Hoya Corporation
    Inventors: Shinji Eda, Hideki Isono
  • Patent number: 8986859
    Abstract: It is an object to provide a magnetic disk substrate highly reliable to prevent the occurrence of crash failure even if a magnetic disk is rotated at high speed, and suitable for a hard disk that starts and stops by the load/unload method, and a magnetic disk using such a substrate. The representative structure of a magnetic disk substrate is a disk-shaped glass substrate 10 having a generally flat main surface 11, an end face 12, a chamfered face 13 formed between the main surface 11 and the end face 12, and an offset portion, at the periphery of the main surface 11, raised or lowered with respect to a flat surface, other than the periphery, of the main surface 11, and characterized in that the magnitude of the offset portion is approximately uniform over the entire circumference of the glass substrate 10.
    Type: Grant
    Filed: July 9, 2012
    Date of Patent: March 24, 2015
    Assignees: Hoya Corporation, Hoya Glass Disk (Thailand) Ltd.
    Inventors: Toshio Takizawa, Kraisorn Phandon, Kenichi Nishimori
  • Patent number: 8966939
    Abstract: Disclosed is a method of producing a glass substrate for an information recording medium including a rough polishing step of performing a rough polishing on a glass material containing 0.01 to 2 mass % of cerium oxide; a washing step of washing the glass material after the rough polishing step, so that the cerium content of the glass material surface becomes 0.125 ng/cm2 or less; and a precision polishing step of performing precision polishing on the glass material after the washing step by cyclically using a polishing material containing colloidal silica.
    Type: Grant
    Filed: March 10, 2011
    Date of Patent: March 3, 2015
    Assignee: Hoya Corporation
    Inventor: Hazuki Nakae
  • Patent number: 8945454
    Abstract: Disclosed is a method for manufacturing a substrate provided with a surface portion having a plurality of concave and convex configurations. The method includes a step of applying a solution between a mold having a configuration corresponding to the concave and convex configurations, and a substrate base member, the solution obtained by dissolving a constructional material for composing the surface portion in a solvent; a step of forming the surface portion by drying the solvent in a state that the solution is applied between the mold and the substrate base member; and a step of releasing the mold from the surface portion. The mold satisfies requirements that a contact angle of a contact portion of the mold to be contacted with the solution is smaller than 90° with respect to the solvent, and that a work of adhesion between the contact portion and the constructional material is smaller than a work of adhesion between the contact portion and the solvent.
    Type: Grant
    Filed: August 13, 2009
    Date of Patent: February 3, 2015
    Assignee: Konica Minolta Opto, Inc.
    Inventors: Akira Sato, Takayuki Okano
  • Patent number: 8940419
    Abstract: Provided are a method for production of a hard disk substrate capable of obtaining a smooth surface of a plating film by electroless NiP plating that is not degraded in, but exhibits corrosion resistance against, an acid solution and such a hard disk substrate.
    Type: Grant
    Filed: October 4, 2011
    Date of Patent: January 27, 2015
    Assignee: Toyo Kohan Co., Ltd.
    Inventor: Nobuaki Mukai
  • Patent number: 8938990
    Abstract: For an information storage medium a glass substrate is produced in a method including the steps of: polishing a glass substrate with a polishing agent applied thereon; and subsequently, chemically strengthening a major surface of the glass substrate. The polishing agent contains cerium oxide at a purity equal to or larger than 99% by mass for CeO2/TREO, and has an alkaline earth metal content having a total mass equal to or smaller than 10 ppm by mass. The step of polishing is performed with a soft polishing pad to polish the glass substrate.
    Type: Grant
    Filed: September 13, 2011
    Date of Patent: January 27, 2015
    Assignee: Hoya Corporation
    Inventors: Hazuki Nakae, Toshiharu Mori
  • Patent number: 8932110
    Abstract: A method of manufacturing a perpendicular magnetic recording medium substrate is capable of reducing the waviness of all wavelength components and a recording medium is capable of reducing contact with a magnetic head to improve the flying stability of the magnetic head. The method includes two polishing operations. The first operation includes polishing a substrate having a Ni—P-based alloy underlayer with a first porous material that includes 0.1 wt % to 25 wt % of alumina, titania, silica, and zirconia abrasive while supplying a first slurry liquid including an organic or inorganic acid and a first abrasive to the underlayer of the substrate. The second operation includes polishing a surface of the underlayer polished in the first polishing with a second porous material while supplying a second slurry liquid including an organic or inorganic acid and a second abrasive with a grain diameter smaller than that of the first abrasive.
    Type: Grant
    Filed: March 11, 2011
    Date of Patent: January 13, 2015
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Shoji Sakaguchi, Masaoki Miyakoshi, Jun Natsume
  • Patent number: 8926759
    Abstract: An object of the invention is to remove effectively metallic contaminants adhering to the glass substrate surfaces without increasing roughness of the glass substrate surfaces in the glass substrate for a magnetic disk. In a manufacturing method of a glass substrate for a magnetic disk, a cleaning step comprising a treatment of contacting the glass substrate with a cleaning liquid containing peroxodisulfate and having a pH of not less than 2 and not more than 4 is appended. In addition, an example of the cleaning liquid can be prepared by adding sodium peroxodisulfate to an acidic solution.
    Type: Grant
    Filed: March 31, 2011
    Date of Patent: January 6, 2015
    Assignee: Hoya Corporation
    Inventors: Takuhiro Hirakawa, Yasunari Hirano, Kouichi Tamoto, Tomoyuki Yamaguchi
  • Patent number: 8919150
    Abstract: An ion-exchanged glass article manufacturing method includes an ion-exchange step of bringing a glass article with a composition containing Li into contact with a molten salt dissolved solution containing an alkali metal element having an ionic radius larger than an ionic radius of the Li contained in the glass article, thereby ion-exchanging the Li in the glass article with the alkali metal element in the molten salt dissolved solution. At least one kind of additive selected from the group consisting of NaF, KF, K3AlF6, Na2CO3, NaHCO3, K2CO3, KHCO3, Na2SO4, K2SO4, KAl(SO4)2, Na3PO4, and K3PO4 is added to the molten salt dissolved solution so that the ion-exchange step is carried out while the additive is in a solid state.
    Type: Grant
    Filed: September 10, 2012
    Date of Patent: December 30, 2014
    Assignee: Hoya Corporation
    Inventors: Mitsugu Imai, Kazuaki Hashimoto, Osamu Sugihara
  • Patent number: 8895165
    Abstract: Provided is a method of manufacturing a magnetic disk glass substrate, wherein, in a main surface polishing process, main surface polishing is applied to one of main surfaces of a glass substrate so that the one main surface has a predetermined arithmetic mean roughness, and main surface polishing is applied to the other main surface of the glass substrate so that the other main surface has a roughness which is higher than the arithmetic mean roughness (Ra) of the one main surface and which is low enough to prevent a component forming the magnetic disk glass substrate from being eluted from the other main surface.
    Type: Grant
    Filed: September 2, 2009
    Date of Patent: November 25, 2014
    Assignees: Hoya Corporation, Hoya Glass Disk (Thailand) Ltd.
    Inventors: Kenichi Nishimori, Tadashi Tomonaga
  • Patent number: 8883330
    Abstract: A glass for use in chemical reinforcement for use in a substrate of an information recording medium, having a composition comprising, denoted as mol %: SiO2 47 to 70%? Al2O3 1 to 10% (where the total of SiO2 and Al2O3 is 57 to 80%) CaO 2 to 25% BaO 1 to 15% Na2O 1 to 10% K2O 0 to 15% (where the total of Na2O and K2O is 3 to 16%) ZrO2 1 to 12% MgO 0 to 10% SrO 0 to 15% (where the ratio of the content of CaO to the total of MgO, CaO, SrO, and BaO is greater than or equal to 0.5) ZnO 0 to 10% (where the total of MgO, CaO, SrO, BaO, and ZnO is 3 to 30%) TiO2 0 to 10% and the total content of the above-stated components is greater than or equal to 95%. A glass for use in chemical reinforcement for use in the substrate of an information recording medium employed in a perpendicular magnetic recording system, in which the glass exhibits the glass transition temperature is greater than or equal to 600° C.
    Type: Grant
    Filed: February 7, 2011
    Date of Patent: November 11, 2014
    Assignee: Hoya Corporation
    Inventors: Mikio Ikenishi, Xuelu Zou
  • Patent number: 8852764
    Abstract: To provide a substrate for information recording medium having various properties, in particular higher fracture toughness, required for application of the substrate for information recording medium of the next generation such as perpendicular magnetic recording system, etc. and a material with excellent workability for such purpose. A crystallized glass substrate for information recording medium, consisting of a crystallized glass which comprises one or more selected from RAl2O4 and R2TiO4 as a main crystal phase, in which R is one or more selected from Zn, Mg and Fe, and in which the main crystal phase has a crystal grain size in a range of from 0.5 nm to 20 nm, a degree of crystallinity of 15% or less, and a specific gravity of 3.00 or less.
    Type: Grant
    Filed: July 18, 2012
    Date of Patent: October 7, 2014
    Assignee: Ohara Inc.
    Inventors: Toshitaka Yagi, Naoyuki Goto
  • Patent number: 8844320
    Abstract: A manufacturing method of a sheet glass material for magnetic disk, the method includes, dropping process for dropping a lump of molten glass; pressing process for sandwiching simultaneously the lump from both sides of the dropping path of the lump with surfaces of a pair of dies facing together, and performing press forming to the lump to obtain a sheet glass material, wherein at least one of the pair of dies has a concave shape with respect to the dropping path of the lump.
    Type: Grant
    Filed: March 30, 2012
    Date of Patent: September 30, 2014
    Assignee: Hoya Corporation
    Inventors: Hideki Isono, Hidekazu Tanino
  • Patent number: 8834983
    Abstract: The present invention provides a base material for disk rolls which is a platy molded article for obtaining ring-shaped disks for use in a disk roll comprising a rotating shaft and ring-shaped disks fitted thereon by insertion, whereby the peripheral surface of the disks serves as a conveying surface, the base material comprising inorganic fibers having a crystallization temperature of 800-900° C., a filler, and a clay. Also disclosed is a disk roll which comprises disks cut out of the base material.
    Type: Grant
    Filed: October 23, 2013
    Date of Patent: September 16, 2014
    Assignee: Nichias Corporation
    Inventors: Masaaki Nakayama, Masatoshi Mitsuta
  • Patent number: 8828482
    Abstract: A disk for a hard disk drive is provided. The disk comprises a substrate comprising aluminum, and a coating layer disposed over the substrate. The coating layer comprises an alloy of Ni, X1 and X2, wherein X1 comprises one or more elements selected from the group consisting of Ag, Au, B, Cr, Cu, Ga, In, Mn, Mo, Nb, Pb, Sb, Se, Sn, Te, W, Zn and Zr, and wherein X2 comprises either B or P, and wherein X1 and X2 do not comprise the same elements.
    Type: Grant
    Filed: March 4, 2013
    Date of Patent: September 9, 2014
    Assignee: WD Media, LLC
    Inventors: Alan J. Ruffini, Lindsey A. Hamilton, Dorothea Buechel-Rimmel, Jean M. Laplante, Ambrose Schaffer, Frederick K. Lowes
  • Patent number: 8802213
    Abstract: A patch for reworking an inconsistent area in a composite structure includes a composite laminate patch adapted to cover the inconsistent area and bonded to the structure by a layer of adhesive. The patch includes a plurality of composite plies having a tapered cross section, and at least first and second regions respectively having differing fracture toughnesses.
    Type: Grant
    Filed: May 27, 2013
    Date of Patent: August 12, 2014
    Assignee: The Boeing Company
    Inventors: Eugene A. Dan-Jumbo, Russell L. Keller, Everett A. Westerman
  • Patent number: 8795859
    Abstract: A magnetic recording medium includes, in a main surface of a glass substrate on which a magnetic recording layer is formed, a plurality of annular first thermally-conductive regions having a larger thermal conductivity than the glass substrate that are provided concentrically with the glass substrate. The first thermally-conductive regions are each provided so that it extends across a plurality of tracks. The first thermally-conductive region has a radial width larger than a depth, from the main surface, of the first thermally-conductive region.
    Type: Grant
    Filed: June 22, 2011
    Date of Patent: August 5, 2014
    Assignee: Hoya Corporation
    Inventors: Naoyuki Fukumoto, Hiroshi Hatano
  • Patent number: 8790799
    Abstract: A method for forming a glass substrate comprises the steps of forming a glass blank with opposing substantially planar surfaces and at least one edge, coating the glass blank in silica-alumina nanoparticles, the silica-alumina nanoparticles comprising an inner core of silica with an outer shell of alumina, annealing the coated glass blank to form a conformal coating of silica-alumina around the glass blank, and polishing the coated glass blank to remove the conformal coating of silica-alumina from the opposing substantially planar surfaces thereof.
    Type: Grant
    Filed: June 22, 2012
    Date of Patent: July 29, 2014
    Assignee: WD Media, LLC
    Inventor: Shoji Suzuki
  • Patent number: 8792201
    Abstract: Processes include aligning a disc with a template at a location so that the pattern from the template is transferred to the disc in a relative orientation. The relative orientation provides that when the disc with the transferred pattern is finally assembled into a hard disc drive, an inner diameter of the spindle hole of the disc may be abutted against an outer diameter of the disc drive spindle, and the data-containing patterns on the discs will be aligned concentrically with a center of the disc drive spindle. While the data-containing patterns are aligned concentrically with the disc drive spindle, the substrate itself is allowed to be non-concentric.
    Type: Grant
    Filed: December 2, 2009
    Date of Patent: July 29, 2014
    Assignee: Seagate Technology LLC
    Inventors: Gennady Gauzner, David S. Kuo, Justin Jia-Jen Hwu, Li-Ping Wang, Zhaoning Yu, Kim Yang Lee
  • Patent number: 8785010
    Abstract: Provided are a magnetic disk substrate and a method of manufacturing the same, wherein the magnetic disk substrate has very few defects present on its surface with an arithmetic mean roughness (Ra) at a level in the vicinity of 0.1 nm and thus is suitable as a substrate for a magnetic disk with high recording density. The magnetic disk glass substrate is such that the arithmetic mean roughness (Ra) of the main surface of the glass substrate measured using an atomic force microscope with a resolution of 256×256 pixels in a 2 ?m×2 ?m square is 0.12 nm or less and the number of defects detected to have a size of 0.1 ?m to 0.6 ?m in plan view and a depth of 0.5 nm to 2 nm is less than 10 per 24 cm2, wherein the defects are each detected using a shift in wavelength between incident light and reflected light upon irradiating and scanning helium neon laser light with a wavelength of 632 nm on the main surface of the glass substrate.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: July 22, 2014
    Assignee: Hoya Corporation
    Inventors: Shinji Eda, Hideki Isono, Takashi Maeda, Hiroshi Tsuchiya, Yoshinori Marumo