发明名称 |
Hematite particles for non-magnetic undercoat layer for magnetic recording medium, process for producing the same, non-magnetic undercoat layer and magnetic recording medium |
摘要 |
<p>High-density acicular hematite particles for a nonmagnetic undercoat layer for a magnetic recording medium have an average major axial diameter of not more than 0.3 mu m, a major axial diameter distribution in geometrical standard of not more than 1.50 and a BET specific surface area of not less than 35 m<2>/g; show a pH of not less than 8; and contain not more than 300 ppm of soluble sodium salt, calculated as Na, and not more than 150 ppm of soluble sulfate, calculated as SO4.</p> |
申请公布号 |
EP0769775(A1) |
申请公布日期 |
1997.04.23 |
申请号 |
EP19960307609 |
申请日期 |
1996.10.18 |
申请人 |
TODA KOGYO CORP. |
发明人 |
HAYASHI, KAZUYUKI;IWASAKI, KEISUKE;TANAKA, YASUYUKI;MORII, HIROKO |
分类号 |
G11B5/738;(IPC1-7):G11B5/704 |
主分类号 |
G11B5/738 |
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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