ABRASIVE MATERIAL COMPOSITION FOR GLASS POLISHING AND POLISHING METHOD USING THE SAME

摘要

PROBLEM TO BE SOLVED: To obtain the subject composition capable of forming a highly accurate polished surface and useful for polishing glass substrates for magnetic disks by including titanium oxide minute particles as abrasive material. SOLUTION: This composition is obtained by including as abrasive material titanium oxide minute particles containing secondary particles having a mean size of preferably 0.1-1.0μm and preferably in addition, at least one kind of magnesium compound (preferably such as magnesium nitrate, magnesium sulfate or magnesium chloride). The composition is preferably in the form of a slurry made by dispersing the above particles in a dispersion medium. The amount of the above titanium oxide particles to be added is preferably 5-30 wt.% as solid concentration in slurry. The composition makes it possible to polish a glass substrate for magnetic disks into a highly accurate mirror finished surface making it suitable for a magnetic head to make a travel at low levitation.