MAGNETPLATTENTRÄGER, MAGNETISCHE PLATTE UND VERFAHREN ZUR HERSTELLUNG DES MAGNETPLATTENTRÄGERS

摘要

A magnetic disc substrate is provided, which includes a magnetic disc substrate body made of glass and is characterized in that a metal element capable of absorbing light in at least a surface portion of the magnetic disc substrate body, and a texture is formed on a surface of the magnetic disc substrate body. Ions of the metal element are dispersed in the surface portion of the magnetic disc substrate, or the metal element is contained in a composition of the glass constituting the magnetic disc substrate in the form of an oxide. The glass is preferably a crystallized glass a Li2O-Al2O3-SiO2 based crystallized glass, which particularly preferably contains 65 to 85 wt% of SiO2, 8 to 15 wt% of Li2O, 2 to 8 wt% of Al2O3, 1 to 5 wt% of P2O5 and 1 to 10 wt% of ZrO2 and has lithium disilicate (Li2O.2SiO2) as a main crystalline phase.