WO2020032146A1 - 磁気ディスク用基板及び磁気ディスク - Google Patents

磁気ディスク用基板及び磁気ディスク Download PDF

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Publication number
WO2020032146A1
WO2020032146A1 PCT/JP2019/031269 JP2019031269W WO2020032146A1 WO 2020032146 A1 WO2020032146 A1 WO 2020032146A1 JP 2019031269 W JP2019031269 W JP 2019031269W WO 2020032146 A1 WO2020032146 A1 WO 2020032146A1
Authority
WO
WIPO (PCT)
Prior art keywords
substrate
magnetic disk
less
thickness
glass
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/JP2019/031269
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English (en)
French (fr)
Japanese (ja)
Inventor
伸二 江田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hoya Corp
Original Assignee
Hoya Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to SG11202100827XA priority Critical patent/SG11202100827XA/en
Priority to CN202310841992.XA priority patent/CN116798456A/zh
Priority to US17/266,079 priority patent/US11640833B2/en
Priority to MYPI2021000408A priority patent/MY208527A/en
Priority to JP2020535859A priority patent/JP6975862B2/ja
Priority to CN201980051118.8A priority patent/CN112513985B/zh
Application filed by Hoya Corp filed Critical Hoya Corp
Publication of WO2020032146A1 publication Critical patent/WO2020032146A1/ja
Anticipated expiration legal-status Critical
Priority to JP2021181989A priority patent/JP7286735B2/ja
Priority to US18/194,619 priority patent/US12020735B2/en
Priority to US18/665,368 priority patent/US12475924B2/en
Priority to US19/383,247 priority patent/US20260065934A1/en
Ceased legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/84—Processes or apparatus specially adapted for manufacturing record carriers
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/62—Record carriers characterised by the selection of the material
    • G11B5/73—Base layers, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
    • G11B5/739—Magnetic recording media substrates
    • G11B5/73911—Inorganic substrates
    • G11B5/73921—Glass or ceramic substrates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B1/00—Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/62—Record carriers characterised by the selection of the material
    • G11B5/73—Base layers, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
    • G11B5/739—Magnetic recording media substrates
    • G11B5/73911—Inorganic substrates
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/62—Record carriers characterised by the selection of the material
    • G11B5/73—Base layers, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
    • G11B5/739—Magnetic recording media substrates
    • G11B5/73911—Inorganic substrates
    • G11B5/73917—Metallic substrates, i.e. elemental metal or metal alloy substrates
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/62—Record carriers characterised by the selection of the material
    • G11B5/73—Base layers, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
    • G11B5/739—Magnetic recording media substrates
    • G11B5/73911—Inorganic substrates
    • G11B5/73917—Metallic substrates, i.e. elemental metal or metal alloy substrates
    • G11B5/73919—Aluminium or titanium elemental or alloy substrates

Definitions

  • FIG. 2 is a diagram illustrating an example of an external shape of a magnetic disk substrate according to one embodiment.
  • FIG. 3 is a diagram illustrating an example of vibration of a magnetic disk substrate according to an embodiment.
  • FIG. 3 is a diagram illustrating an example of an outer peripheral end portion of the magnetic disk of one embodiment.
  • the Vickers hardness Hv is 128 [kgf / mm 2 ] for an aluminum alloy substrate and 620 [kgf / mm 2 ] for a conventional glass substrate, whereas the glass Vickers hardness Hv is one embodiment.
  • the substrate 1 it is 741 [kgf / mm 2 ].
  • a press molding method can be used.
  • a circular glass blank can be obtained.
  • it can be manufactured by using a known manufacturing method such as a downdraw method, a redraw method, and a fusion method.
  • a disk-shaped substrate serving as a base for a magnetic disk substrate can be obtained by appropriately shaping the plate-shaped glass blanks produced by these known production methods.
  • chemical strengthening may be appropriately performed.
  • chemical strengthening for example, potassium nitrate, sodium nitrate, or a melt obtained by heating a mixture thereof can be used as the chemical strengthening liquid.
  • lithium ions and sodium ions in the glass composition on the surface layer of the substrate are replaced with sodium ions and potassium ions, respectively, having relatively large ionic radii in the chemical strengthening liquid.
  • a compressive stress layer is formed on the surface layer, and the substrate is reinforced.
  • the timing at which the chemical strengthening is performed can be determined as appropriate. However, it is particularly preferable to perform the polishing after the chemical strengthening, since the surface can be smoothed and the foreign matter adhered to the surface of the substrate by the chemical strengthening can be removed.
  • the maximum amplitude is 0.25 mm or less, it can be determined that contact with the lamp does not occur. If the maximum amplitude exceeds 0.25 mm, the possibility of contact with another member is extremely high.
  • the maximum amplitude was checked for three substrates, and the average value of each maximum amplitude was used. In this evaluation, the substrate was evaluated in a stationary state without rotating. It should be noted that the thickness of the magnetic film or the like formed in the media process is substantially 100 nm or less on the main surface and can be substantially ignored.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Inorganic Chemistry (AREA)
  • Metallurgy (AREA)
  • Ceramic Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Magnetic Record Carriers (AREA)
  • Manufacturing Of Magnetic Record Carriers (AREA)
  • Glass Compositions (AREA)
  • Paints Or Removers (AREA)
  • Laminated Bodies (AREA)
PCT/JP2019/031269 2018-08-07 2019-08-07 磁気ディスク用基板及び磁気ディスク Ceased WO2020032146A1 (ja)

Priority Applications (10)

Application Number Priority Date Filing Date Title
CN202310841992.XA CN116798456A (zh) 2018-08-07 2019-08-07 磁盘用基板以及磁盘
US17/266,079 US11640833B2 (en) 2018-08-07 2019-08-07 Substrate for magnetic disk and magnetic disk
MYPI2021000408A MY208527A (en) 2018-08-07 2019-08-07 Substrate for magnetic disk and magnetic disk
JP2020535859A JP6975862B2 (ja) 2018-08-07 2019-08-07 磁気ディスク用基板及び磁気ディスク
CN201980051118.8A CN112513985B (zh) 2018-08-07 2019-08-07 磁盘用基板以及磁盘
SG11202100827XA SG11202100827XA (en) 2018-08-07 2019-08-07 Substrate for magnetic disk and magnetic disk
JP2021181989A JP7286735B2 (ja) 2018-08-07 2021-11-08 磁気ディスク用基板及び磁気ディスク
US18/194,619 US12020735B2 (en) 2018-08-07 2023-04-01 Substrate for magnetic disk and magnetic disk
US18/665,368 US12475924B2 (en) 2018-08-07 2024-05-15 Substrate for magnetic disk and magnetic disk
US19/383,247 US20260065934A1 (en) 2018-08-07 2025-11-07 Glass substrate for magnetic disk

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2018148923 2018-08-07
JP2018-148923 2018-08-07
JP2019009901 2019-01-24
JP2019-009901 2019-01-24

Related Child Applications (2)

Application Number Title Priority Date Filing Date
US17/266,079 A-371-Of-International US11640833B2 (en) 2018-08-07 2019-08-07 Substrate for magnetic disk and magnetic disk
US18/194,619 Continuation US12020735B2 (en) 2018-08-07 2023-04-01 Substrate for magnetic disk and magnetic disk

Publications (1)

Publication Number Publication Date
WO2020032146A1 true WO2020032146A1 (ja) 2020-02-13

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2019/031269 Ceased WO2020032146A1 (ja) 2018-08-07 2019-08-07 磁気ディスク用基板及び磁気ディスク

Country Status (6)

Country Link
US (4) US11640833B2 (https=)
JP (5) JP6975862B2 (https=)
CN (2) CN112513985B (https=)
MY (1) MY208527A (https=)
SG (1) SG11202100827XA (https=)
WO (1) WO2020032146A1 (https=)

Cited By (5)

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Publication number Priority date Publication date Assignee Title
JP2022090912A (ja) * 2020-12-08 2022-06-20 株式会社Uacj 磁気ディスク基板および磁気ディスク
CN115812238A (zh) * 2020-07-03 2023-03-17 株式会社Uacj 磁盘用基板及使用该磁盘用基板的磁盘
WO2023100893A1 (ja) * 2021-12-01 2023-06-08 日本電気硝子株式会社 磁気記録媒体用ガラス基板、磁気記録媒体用ガラスディスク、磁気記録媒体及びガラスディスクの製造方法
JPWO2023136242A1 (https=) * 2022-01-11 2023-07-20
WO2024202050A1 (ja) * 2023-03-31 2024-10-03 Hoya株式会社 情報記録媒体用ディスク、ディスク中間体、及び情報記録媒体用基板

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
MY208527A (en) 2018-08-07 2025-05-14 Hoya Corp Substrate for magnetic disk and magnetic disk
JP7113157B1 (ja) * 2022-03-30 2022-08-04 古河電気工業株式会社 磁気ディスク及び磁気ディスク用基板
WO2025143137A1 (ja) * 2023-12-27 2025-07-03 Hoya株式会社 情報記録媒体用ディスク

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CN115812238A (zh) * 2020-07-03 2023-03-17 株式会社Uacj 磁盘用基板及使用该磁盘用基板的磁盘
US20230238027A1 (en) * 2020-07-03 2023-07-27 Uacj Corporation Magnetic disk substrate and magnetic disk using magnetic disk substrate
US12555602B2 (en) * 2020-07-03 2026-02-17 Uacj Corporation Magnetic disk substrate and magnetic disk using magnetic disk substrate
JP2022090912A (ja) * 2020-12-08 2022-06-20 株式会社Uacj 磁気ディスク基板および磁気ディスク
WO2023100893A1 (ja) * 2021-12-01 2023-06-08 日本電気硝子株式会社 磁気記録媒体用ガラス基板、磁気記録媒体用ガラスディスク、磁気記録媒体及びガラスディスクの製造方法
JPWO2023136242A1 (https=) * 2022-01-11 2023-07-20
JP7717846B2 (ja) 2022-01-11 2025-08-04 古河電気工業株式会社 磁気ディスク用基板及びこれを用いた磁気ディスク
WO2024202050A1 (ja) * 2023-03-31 2024-10-03 Hoya株式会社 情報記録媒体用ディスク、ディスク中間体、及び情報記録媒体用基板

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