| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a glass substrate for a vertical magnetic recording disk having≤2.0Åaverage surface roughness and≤1Åheight difference of ups and downs between the circumferential direction and the radial direction of wavelength of 0.05 to 0.5 mm, and to provide its manufacturing method. <P>SOLUTION: The glass substrate 15 is rotated, polishing slurry is supplied, polishing tapes 14 are pushed to the glass substrate and then the polishing tapes are sent out. Artificial diamond particles consisting of an artificial diamond formed by an impact method and having <50 nm particle diameter are used as grinding particles. Grinding particle content per a total amount of the polishing slurry is in the range of 0.005 to 0.5 wt.%, preferably 0.005 to 0.1 wt.%. As the polishing tape, a tape comprising woven fabric, nonwoven fabric, flocked fabric or raising fabric comprising fibers at least the surface part of which are pushed to the surface of the glass substrate and have 0.1 to 5.0μm size is used. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
