Title:
MANUFACTURING METHOD OF GLASS SUBSTRATES FOR MAGNETIC DISKS
Document Type and Number:
WIPO Patent Application WO/2011/125902
Kind Code:
A1
Abstract:
One goal of the disclosed manufacturing method of glass substrates for magnetic disks is to effectively remove glass substrate surface particles even when low particle diameter abrasive grains are used in a glass substrate polishing step and ultrasonic treatment is performed at a high frequency in an ultrasonic cleaning step after the polishing step. The manufacturing method of glass substrates for magnetic disks involves a polishing step for polishing a glass substrate, and, after the polishing step, an ultrasonic cleaning step for ultrasonic cleaning of the glass substrate, wherein polishing abrasive grains of diameter of 10-30nm are used in the polishing step, and in the ultrasonic cleaning step, after performing a first ultrasonic cleaning at a frequency of 300KHz-1000KHz and forming secondary particles, a second ultrasonic cleaning is performed at a frequency of 30KHz-100KHz.
Inventors:
SUZUKI, Yosuke (7-5 Naka-Ochiai 2-chome, Shinjuku-k, Tokyo 25, 〒1618525, JP)
Application Number:
JP2011/058332
Publication Date:
October 13, 2011
Filing Date:
March 31, 2011
Export Citation:
Assignee:
HOYA CORPORATION (7-5 Naka-Ochiai 2-chome, Shinjuku-ku Tokyo, 25, 〒1618525, JP)
ＨＯＹＡ株式会社 (〒25 東京都新宿区中落合２丁目７番５号 Tokyo, 〒1618525, JP)
ＨＯＹＡ株式会社 (〒25 東京都新宿区中落合２丁目７番５号 Tokyo, 〒1618525, JP)
International Classes:
G11B5/84; C03C19/00; C03C23/00
Attorney, Agent or Firm:
AOKI, Hiroyoshi et al. (7F Nibancho Cashew Bldg, 4-3 Niban-cho, Chiyoda-k, Tokyo 84, 〒1020084, JP)
Claims: