Polishing composition and method for producing a memory hard disks

Abstract

A polishing composition for a magnetic disk substrate to be used for a memory hard disk, which comprises: (a) colloidal silica as an abrasive in an amount within a range of from 0.1 to 35 wt % based on the total weight of the composition; (b) iron nitrate as a polishing accelerator in an amount within a range of from 0.04 to 2.2 wt % based on the total weight of the composition; (c) citric acid as a stabilizer in an amount within a range of from 0.4 to 22 wt % based on the total weight of the composition; (d) hydrogen peroxide as a polishing acceleration assistant in an amount within a range of from 0.155 to 9.3 wt % based on the total weight of the composition; and (e) water.

Dependencies are inferred from the claim text.