Process for manufacturing glass hard disc substrates

Abstract

Provided is a method for producing a glass hard disk substrate, including steps of polishing a glass substrate with an acidic polishing liquid; and subjecting the obtained substrate to alkali cleaning. This method can inhibit degradation of surface roughness of the glass substrate in the alkali cleaning step while maintaining a polishing rate in the polishing step, and further can improve cleanliness. The method for producing a glass hard disk substrate includes the following steps (1) and (2): (1) polishing a glass substrate to be polished using a polishing composition of pH 1.0-4.2 that contains a polyvalent amine compound having 2 to 10 nitrogen atoms in the molecule; and (2) cleaning the substrate obtained in the step (1) using a cleaner composition of pH 8.0-13.0.

Dependencies are inferred from the claim text.