| abstract |
A polishing composition for a memory hard disc, which comprises the following components (a) to (d): (a) water, (b) at least one compound selected from the group consisting of a polystyrenesulfonic acid, and its salts, (c) a compound selected from the group consisting of an inorganic acid and an organic acid, and their salts, other than component (b), and (d) at least one abrasive selected from the group consisting of aluminum oxide, silicon dioxide, cerium oxide, zirconium oxide, titanium oxide, silicon nitride and manganese dioxide. |