Invention Grant
US08328602B2 Glass substrate for information recording medium and method for manufacturing the same, and magnetic recording medium 失效
用于信息记录介质的玻璃基板及其制造方法和磁记录介质

Glass substrate for information recording medium and method for manufacturing the same, and magnetic recording medium
Abstract:
The present invention relates to a method for manufacturing a glass substrate for information recording medium, the method including: a lapping step of lapping a circular glass plate made of an alkali aluminosilicate glass; and a subsequent cerium oxide polishing step of polishing the circular glass plate with a slurry containing a cerium oxide abrasive, in which a difference (SiO2−Al2O3) obtained by subtracting an Al2O3 content from an SiO2 content in the alkali aluminosilicate glass is 62% by mole or less; and in which the method further includes: subsequently to the cerium oxide polishing step, a cleaning step of cleaning the circular glass plate with a cleaning liquid having a sulfuric acid concentration of 20% by mass or more and 80% by mass or less and a hydrogen peroxide concentration of 1% by mass or more and 10% by mass or less at a liquid temperature of 50° C. or higher and 100° C. or lower, and after the cleaning step, a finish polishing step of polishing a main surface of the circular glass plate with a slurry containing a colloidal silica abrasive.
Information query
Patent Agency Ranking
0/0