Title:
PRODUCTION METHOD FOR GLASS SUBSTRATE FOR INFORMATION RECORDING MEDIUM
Document Type and Number:
WIPO Patent Application WO/2013/047190
Kind Code:
A1
Abstract:
In this production method for a glass substrate for a magnetic recording medium, a step in which a first surface-strengthened layer (101A) and a second surface-strengthened layer (101B) are polished is a step in which the first surface-strengthened layer (101A) and the second surface-strengthened layer (101B) are polished such that both a first polishing amount difference (P1) and a second polishing amount difference (P2) are no more than 0.10 µm, when: the difference between the polishing amount for the first surface-strengthened layer (101A) and the polishing amount for the second surface-strengthened layer (101B) in a first circumferential region (C1) having a distance in the diameter direction towards the rotation center (CP) from the outer peripheral edge surface (12) of 2.5 mm is called the first polishing amount difference (P1); and the difference between the polishing amount for the first surface-strengthened layer (101A) and the polishing amount for the second surface-strengthened layer (101B) in a second circumferential region (C2) having a distance in the diameter direction towards the rotation center (CP) from the outer peripheral edge surface (12) of 6.5 mm is called the second polishing amount difference (P2).
More Like This:
| JPH1021537 | PRODUCTION OF MAGNETIC RECORDING MEDIUM |
| JPS59148125 | MAGNETIC RECORDING MEDIUM |
| JPS51110307 | JIKIKIROKUTAINO SETSUDANHOHO |
Inventors:
ENDO TAKESHI (JP)
MIYAMOTO HIROSHI (JP)
MIYAMOTO HIROSHI (JP)
Application Number:
PCT/JP2012/073193
Publication Date:
April 04, 2013
Filing Date:
September 11, 2012
Export Citation:
Assignee:
KONICA MINOLTA ADVANCED LAYERS (JP)
ENDO TAKESHI (JP)
MIYAMOTO HIROSHI (JP)
ENDO TAKESHI (JP)
MIYAMOTO HIROSHI (JP)
International Classes:
G11B5/84; C03C19/00; C03C21/00
Foreign References:
| JPH07134823A | 1995-05-23 | |||
| JPH09309064A | 1997-12-02 |
Attorney, Agent or Firm:
Fukami Patent Office, p. c. (JP)
Patent business corporation Fukami patent firm (JP)
Patent business corporation Fukami patent firm (JP)
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