| abstract |
For providing glass-ceramics having properties suitable for use as a substrate of an information storage medium of next generation such as one for the perpendicular magnetic recording system without employing arsenic and antimony components which adversely affect human beings and the environment, there are provided glass-ceramics comprising SiO2, Li2O and Al2O3 on oxide basis, comprising lithium disilicate as a crystal phase, and comprising one or more elements selected from the group consisting of Sn, Ce, Mn, W, Ta, Bi, Nb, S, Cl and F. |