| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic disk substrate manufacturing method, capable of reducing long-period faults on a substrate surface after rough grinding according to one aspect.SOLUTION: According to one aspect, a manufacturing method comprises: an abrasive step (1) using an abrasive liquid composition I; a step (2) of washing an obtained substrate; and a step (3) of grinding the obtained substrate using an abrasive liquid composition II containing silica particles C, the steps (1) and (3) being executed by different abrasive machines, the abrasive liquid composition I containing non-spherical silica particles A, spherical silica particles B, an acid, an oxidant, and water and having a mass ratio (A/B) of not less than 80/20 and not more than 99/1, a total content of the silica particles A and B exceeding 98.0 mass%, a &Dgr;CV value of the non-spherical silica particles A being more than 0.0% and less than 10%, a particle diameter ratio (D1/D2) of the non-spherical silica particles A being not less than 2.00 and not more than 4.00, a volume average particle diameter (D1) of the spherical silica particles B being not less than 6.0 nm and not more than 80.0 nm, and the oxide being any of phosphoric acids, a phosphonic acid or an organic phosphonic acid.SELECTED DRAWING: None |
