MAGNETIC DISK SUBSTRATE, MAGNETIC DISK, AND PROCESS FOR PRODUCING MAGNETIC DISK SUBSTRATE

摘要

A magnetic disk substrate having the body made from glass, characterized by containing light-absorbing metal elements in at least the surface region of the substrate body and having a texture formed on the surface of the body. The metal elements are diffused in the surface region as metal ions or contained in the glass ingredients as metal oxides. Preferable examples of the glass include crystallized LiO2-Al2O3-SiO2 glasses, more particularly those composed of 65-85 wt.% SiO2, 8-15 wt.% Li2O, 2-8 wt.% Al2O3, 1-5 wt.% P2O5, and 1-10 wt.% ZrO2, and containing lithium disilicate (LiO2.2SiO2) as the principal crystal phase.