发明名称 |
Master disc and method for manufacturing magnetic disc using the same |
摘要 |
A master disc capable of conducting a preformat recording by a magnetic transcription without causing any unevenness over an entire magnetic disc is provided. The master disc is provided with a radial land portion where an array of ferromagnetic thin films is formed and a concave portion against the land portion. The land portion and the concave portion are formed such that the land portion is joined with the surface of the magnetic disc when the present magnetic disc is overlapped on the magnetic disc, and that the concave portion is not contacted with the surface of the magnetic disc, and also that a space surrounded by the surface of the magnetic disc and the concave portion is open to air at a peripheral end portion of the magnetic disc.
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申请公布号 |
US6858329(B2) |
申请公布日期 |
2005.02.22 |
申请号 |
US20020980183 |
申请日期 |
2002.04.30 |
申请人 |
MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. |
发明人 |
HAMADA TAIZOU;HASHI HIDEYUKI;ISHIDA TATSUAKI;KOMURA NOBUYUKI;BAN YASUAKI;MIYATA KEIZO;TOHMA KIYOKAZU |
分类号 |
G11B5/596;G11B5/82;G11B5/86;G11B23/50;(IPC1-7):G11B5/66 |
主分类号 |
G11B5/596 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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