Title:
PROCESS FOR PRODUCING GLASS SUBSTRATE FOR HDD, GLASS SUBSTRATE FOR HDD, AND MAGNETIC RECORDING MEDIUM FOR HDD
Document Type and Number:
WIPO Patent Application WO/2013/001797
Kind Code:
A1
Abstract:
Provided is a process for producing a glass substrate for HDDs which inhibits head crushing even when used in a magnetic recording medium for HDDs that is to be mounted in an HDD equipped with a DFH head mechanism. Also provided are a glass substrate for HDDs and a magnetic recording medium for HDDs. The process for producing a glass substrate for HDDs includes a chemical strengthening step in which a glass substrate is chemically strengthened by immersing the glass substrate in a liquid for chemical strengthening. In the chemical strengthening step, the increase in the circumferential-direction TIR of the glass substrate through the chemical strengthening step is regulated to 0.5 µm or less by changing the attitude of the glass substrate within the chemical strengthening liquid in which the glass substrate is being immersed, and/or by flatting the temperature distribution of the chemical strengthening liquid, and/or by stirring the chemical strengthening liquid.
Inventors:
FUKUMOTO NAOYUKI (JP)
Application Number:
PCT/JP2012/004140
Publication Date:
January 03, 2013
Filing Date:
June 27, 2012
Export Citation:
Assignee:
KONICA MINOLTA ADVANCED LAYERS (JP)
FUKUMOTO NAOYUKI (JP)
FUKUMOTO NAOYUKI (JP)
International Classes:
G11B5/84; C03C19/00; C03C21/00; G11B5/73
Domestic Patent References:
| WO2011155132A1 | 2011-12-15 | |||
| WO2011096310A1 | 2011-08-11 |
Foreign References:
| JP2008204521A | 2008-09-04 | |||
| JP2007012247A | 2007-01-18 |
Attorney, Agent or Firm:
KOTANI, Etsuji et al. (JP)
Etsuji Kotani (JP)
Etsuji Kotani (JP)
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Claims: