发明名称 Acicular hematite particles having a low sodium content and their use in a magnetic recording medium
摘要 The present invention provides particles for a non-magnetic undercoat layer of a magnetic recording medium, which comprises particular hematite particles having an average major axial diameter of not more than 0.3 mum, a geometrical standard deviation in the major axial diameter of not more than 1.50 and a BET specific surface area of not less than 40 m2/g, and containing a total amount of sodium of not more than 50 ppm calculated as Na. The particular hematite particles have an excellent dispersibility in a vehicle so that a non-magnetic undercoat layer containing the particles is excellent in surface smoothness and strength. A magnetic recording medium using the non-magnetic undercoat layer is excellent not only in electromagnetic performance, but in storage stability.
申请公布号 US6299973(B1) 申请公布日期 2001.10.09
申请号 US19990420008 申请日期 1999.10.18
申请人 TODA KOGYO CORPORATION 发明人 HAYASHI KAZUYUKI;IWASAKI KEISUKE;MORII HIROKO
分类号 C01G49/06;C09C1/24;G11B5/73;G11B5/733;G11B5/738;(IPC1-7):G11B5/738 主分类号 C01G49/06
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