Abstract: Magnetic recording media having a protective carbon overcoat adapted to protect the magnetic recording layer from surface contact events and corrosion. The carbon overcoat includes at least two layers. A first layer is adapted to protect the magnetic recording layer from surface contact events and corrosion. The second layer is disposed on the first layer and is adapted to enhance the bonding of a lubricant to the carbon overcoat and to minimize head degradation. The magnetic recording media of the present invention advantageously enables the use of thin carbon overcoats, enhancing areal density, while maintaining good tribological properties.
Type:
Grant
Filed:
October 11, 2002
Date of Patent:
April 5, 2005
Assignee:
Maxtor Corporation
Inventors:
Shahid A. Pirzada, Ian L. Sanders, Jia-Jay Liu, Kenneth E. Johnson
Abstract: A magnetic recording medium comprising a magnetic layer, a support and a backing layer in this order, wherein the backing layer comprises a binder and an inorganic powder having a surface covered with an electrically conductive substance.
Abstract: A method of manufacturing a magnetic recording medium comprises steps of providing a non-magnetic substrate having at least one surface; forming a layer of a sol-gel on the surface, partially drying the sol-gel layer at room temperature to remove a portion of the solvent therein to form a partially dried sol-gel layer of hardness less than that of the substrate; mechanically texturing the surface of the partially dried sol-gel layer; and depositing a layer stack including at least one magnetic layer thereover. Embodiments of the invention include embossing a servo pattern in the as-deposited sol-gel layer prior to partial drying and mechanically texturing, followed by sintering at an elevated temperature to form a substantially fully dried layer having a density and hardness similar to that of glass, and formation of a thin film magnetic media layer stack thereon.
Type:
Grant
Filed:
May 12, 2004
Date of Patent:
March 15, 2005
Assignee:
Seagate Technology LLC
Inventors:
Hong Ying Wang, Joseph Leigh, Neil Deeman, David Kuo
Abstract: A foil-decorating sheet (4) comprised by a laminated film of two or more kinds of films which is to be set in an injection mold (5, 6) for being integrally bonded to a surface of a molding resin (10), wherein after a foil-decorating is made, a bonding surface-side film (3) of the laminated film which is bonded to the molding resin (10) has a peel strength of not less than 1 kgf/inch width at least at an interface between the surface film (3) of the laminated film bonded to the molding resin (10) and the molding resin (10), and wherein at least a transparent acrylic film (1) is laminated on the bonding surface-side film (3) bonded to the molding resin, with a decorative layer (2) formed between the bonding surface-side film (3) bonded to the molding resin and the acrylic film (1).
Abstract: A disk-shaped magnetic recording medium for use in a small magnetic disk cartridge, comprising a flexible disk-shaped magnetic sheet, and a rigid annular member attached to the outer circumferential edge portion of one side of the magnetic sheet.
Abstract: A glass substrate for magnetic disks, which is a doughnut-type glass substrate having an inner periphery and an outer periphery, wherein an electrically conductive coat is formed on at least the outer peripheral edge surface.
Abstract: Elastomeric fluoropolyether lubricant topcoats are formed on a protective overcoat of a magnetic recording medium. Embodiments include forming a an amorphous carbon layer having a thickness of no greater than about 25 ? as the protective overcoat and polymerizing a fluorpolyether having one or more acrylate groups on the amorphous carbon layer to form the elastomeric fluoropolyether topcoat lubricant directly on the protective overcoat.
Abstract: A method for making a magnetic disk comprises forming first and second protective carbon layers on a magnetic layer. The first protective carbon layer is predominantly SP3 carbon. The second protective carbon layer comprises about 50% or less SP3 carbon. The second protective carbon layer is very thin, e.g. between 0.1 and 1.0 nm thick. A lubricant layer (e.g. a perfluoropolyether lubricant) is applied to the second protective carbon layer. The second protective carbon layer facilitates improved cooperation between lubricant and the disk.
Type:
Grant
Filed:
December 5, 2003
Date of Patent:
February 15, 2005
Assignee:
Komag, Inc.
Inventors:
Bruce Jairson, Ching Jackie Tsoi, Wen Liu, Shigeto Hashimoto, Eric Woo Hock Yong, Tsutomu Tom Yamashita
Abstract: A magnetic recording medium is disclosed, comprising a support having provided thereon a substantially nonmagnetic lower layer by coating a lower layer coating solution comprising a nonmagnetic powder dispersed in a binder and drying, and a layer having a thickness of from 0.01 to 0.15 ?m by coating a magnetic layer coating solution comprising a ferromagnetic metal powder or a hexagonal ferrite powder dispersed in a binder, wherein the magnetic layer contains diamond particles having an average particle size of from 1/5 to 2 times the thickness of the magnetic layer in an amount of from 0.1 to 5.0 mass % based on the ferromagnetic metal powder.
Abstract: A magnetic recording medium comprises a back coat layer containing carbon black and alumina as non-magnetic powder. The relationship between the abrasivity (y) in microns of the back coat layer and the alumina content (x) parts by weight to 100 parts by weight of non-magnetic powder excluding alumina satisfies four equations y?4.6x+12.2, y?4.1x+10.8, y?13, y?17. The abrasivity is measured such that an edge of a prismatic Sendust bar is pushed perpendiculary onto the back coat layer such that the magnetic recording medium is pressed at an approaching angle of 12 degree, and the magnetic recording medium is supported by a tension of 0.526 N/cm per unit width and a 50-m length thereof is moved back and forth one time over the Sendust bar at a running speed of 0.3 m/s.
Abstract: Provided is a particulate magnetic recording medium for high-density recording having a low error rate and good running durability. The magnetic recording medium comprises a nonmagnetic layer comprising a nonmagnetic powder and a binder and a magnetic layer comprising a ferromagnetic powder and a binder in this order on at least one surface of a nonmagnetic support. Said nonmagnetic support comprises a clay mineral coated with an organic material, and said ferromagnetic powder is a ferromagnetic hexagonal ferrite powder having an average plate diameter ranging from 5 to 40 nm or a ferromagnetic metal powder having an average major axis length ranging from 20 to 100 nm.
Abstract: The average major-axis length (L) of a ferromagnetic alloy powder primarily contained together with a binder in a magnetic layer provided on at least one surface of a non-magnetic support is less than 0.10 ?m, and the ferromagnetic alloy powder contains Co at a content of 15 to 28 at % relative to Fe, and furthermore, contains Y at a content of 22 ?mol/m2 or more with respect to a specific surface area (Sc) calculated from the above-mentioned average major-axis length (L) and the crystallite diameter (d). A coating-type high-recording-density magnetic recording medium has excellent surface properties, an excellent electromagnetic transducing characteristic especially in short wavelength regions and high reliability.
Abstract: An improved system and method for displaying a sample representing an appearance of a surface of an object. The method may include providing laminations having a flexible magnetic layer and a flexible paint sample layer. The laminations are selectively placed on the ferromagnetic body with the magnetic layer adjacent to the body such that the lamination is detachably attached to the body while the paint sample layer is displayed thereon. The lamination can be placed on flat and/or curved portions of the body. When placed on curved portions, the lamination flexibly bends thereon and assumes the shape of the curved portion. The system and method are also applicable in a variety of other contexts to provide sample appearances of various aspects of an object.
Abstract: A substrate for an information recording medium has a microwaviness average height Ra? not greater than 0.05 microinch as measured by a contactless laser interference technique for measurement points within a measurement region of 50 ?m?-4 mm? on a surface of the substrate. The microwaviness average height Ra? is given by: Ra ? = 1 n ? ? i = 1 n ? ? | xi - x _ | , where xi represents a measurement point value of each measurement point, {overscore (x)} representing an average value of the measurement point values, n representing the number of said measurement points. Alternatively, the substrate has a waviness period between 300 ?m and 5 mm and a waviness average height Wa of 1.0 nm or less as measured by the contactless laser interference technique for measurement points in a measurement region surrounded by two concentric circles which is spaced from a center of a surface of the substrate by a predetermined distance.
Abstract: Thin lubricant films are prepared on optical and magnetic substrates by applying a lubricant having at least one UV polymerizable group onto the substrate and polymerizing the lubricant by UV irradiation at elevated temperatures. Embodiments include applying a lubricant having at least two acrylate groups onto a magnetic recording disc, heating the magnetic recording disc from about 50° C. to about 150° C. and exposing the lubricant to UV radiation substantially free of wavelengths of 200 nm or less.
Type:
Grant
Filed:
March 4, 2002
Date of Patent:
February 1, 2005
Assignee:
Seagate Technology LLC
Inventors:
Jianwei Liu, Michael Stirniman, Dan Castro
Abstract: Provided is a magnetic recording medium having high C/N, low error rate, and excellent running durability. The magnetic recording medium comprises a magnetic layer 1 comprising a ferromagnetic powder and a binder, or comprising a nonmagnetic layer comprising a nonmagnetic powder and a binder and a magnetic layer 2 comprising a ferromagnetic powder and a binder in this order on a nonmagnetic support. An undercoating layer comprising a clay mineral coated with an organic compound and a binder is comprised between the nonmagnetic support and the magnetic layer 1 or between the nonmagnetic support and the nonmagnetic layer, as well as said clay mineral coated with an organic compound has a thickness ranging from 0.5 to 5 nm and an aspect ratio ranging from 50 to 10,000.
Abstract: A method of increasing the performance of a composite lubricant material when utilized as a thin film lubricant, comprising: (a) providing a substrate including a surface; (b) providing a composite lubricant comprising a mixture of at least one perfluoropolyether compound and at least one phosphite or phosphate compound; (c) applying a thin layer of the composite lubricant to the substrate surface; and (d) treating the thin layer of composite lubricant with UV radiation at a dosage and for an interval sufficient to reduce the surface tension, increase the corrosion resistance, increase the durability and reduce the stiction/friction of the thin layer of composite lubricant.
Type:
Grant
Filed:
December 23, 2002
Date of Patent:
January 25, 2005
Assignee:
Seagate Technology LLC
Inventors:
Jianwei Liu, Michael Joseph Stirniman, Jing Gui
Abstract: An object of the present invention is to provide a process for easily producing a magnetic recording medium exhibiting excellent magnetic characteristics. In the present invention, an orientation-determining film is formed on a non-metallic substrate which has undergone texturing, the orientation-determining film is subjected to oxidation or nitridation, and a non-magnetic undercoat film and a magnetic film are formed on the film.
Abstract: A magnetic recording medium comprising: a support; and a magnetic layer comprising ferromagnetic metal powder and a binder, wherein the ferromagnetic metal powder is acicular composite magnetic particle powder having an average long axis length of from 20 to 50 nm, and at least a part of a surface of the particle powder is covered with carbon black.
Abstract: A magnetic recording tape comprising a magnetic layer, a flexible support and a backcoating layer in this order, wherein the backcoating layer has on its surface 10 to 200 projections having a height of 50 to 100 nm per 90 &mgr;m side square as measured with an atomic force microscope and 10 or fewer projections having a height greater than 100 nm and not greater than 500 nm per 90 &mgr;m side square as measured with an atomic force microscope, and the tape has a cupping of 3 to 20% of the tape width with convexity on the magnetic layer side.