Glass for information recording media substrate, glass substrate for magnetic disk and magnetic disk
    9.
    发明授权
    Glass for information recording media substrate, glass substrate for magnetic disk and magnetic disk 有权
    用于信息记录介质基板的玻璃,用于磁盘和磁盘的玻璃基板

    公开(公告)号:US08119268B2

    公开(公告)日:2012-02-21

    申请号:US12881236

    申请日:2010-09-14

    IPC分类号: G11B5/62 C03C3/091 C03C3/087

    摘要: To provide a glass for an information recording media substrate, which is excellent in weather resistance.A glass for an information recording media substrate, which comprises, as represented by mol % based on oxide, from 61 to 66% of SiO2, from 11.5 to 17% of Al2O3, from 8 to 16% of Li2O, from 2 to 8% of Na2O, from 2.5 to 8% of K2O, from 0 to 6% of MgO, from 0 to 4% of TiO2 and from 0 to 3% of ZrO2, provided that Al2O3+MgO+TiO2 is at least 12%, and Li2O+Na2O+K2O is from 16 to 23%, wherein in a case of where B2O3 is contained, its content is less than 1%. The above glass for an information recording media substrate, wherein when the glass is left under steam atmosphere at 120° C. at 0.2 MPa for 20 hours, and the amount of Li, the amount of Na and the amount of K, which precipitate on a surface of the glass are represented as CLi, CNa and CK respectively, CNa is at most 0.7 nmol/cm2, and CLi+CNa+CK is at most 3.5 nmol/cm2.

    摘要翻译: 提供耐候性优异的信息记录介质基板用玻璃。 用于信息记录介质基板的玻璃,其以氧化物的摩尔%表示,SiO 2的61至66%,Al 2 O 3的11.5至17%,Li 2 O的8至16%,2至8重量% 的Na 2 O,2.5〜8%的K 2 O,0〜6%的MgO,0〜4%的TiO 2和0〜3%的ZrO 2,条件是Al 2 O 3 + MgO + TiO 2为至少12%,Li 2 O + Na 2 O + K 2 O为16〜23%,其中,在含有B 2 O 3的情况下,其含量小于1%。 上述用于信息记录介质基板的玻璃,其中当玻璃在蒸气气氛中在120℃下在0.2MPa下放置20小时时,并且Li的量,Na的量和沉淀的K的量 玻璃的表面分别表示为CLi,CNa和CK,CNa为0.7nmol / cm 2以下,CLi + CNa + CK为3.5nmol / cm 3以下。