Acicular cobalt-modified iron oxides and their preparation
    4.
    发明授权
    Acicular cobalt-modified iron oxides and their preparation 失效
    精氨酸改性铁氧化物及其制备

    公开(公告)号:US5183709A

    公开(公告)日:1993-02-02

    申请号:US507765

    申请日:1990-05-21

    摘要: Acicular, cobalt-modified iron oxides consisting of a core of an iron oxide of the formula FeO.sub.x where x is from 1.33 to 1.5 and a ferrite shell which contains a total amount of from 0.4 to 12% by weight of cobalt ions and not more than 5% by weight of iron(II) ions, the percentages being based on the total amount of the material, which iron oxides have improved aging resistance, particularly with regard to the coercive forces, and a process for their preparation.

    摘要翻译: 针状,由铁FeOx的氧化铁核心组成的钴改性的氧化铁,其中x为1.33至1.5,铁氧体壳含有总计为0.4-12重量%的钴离子且不大于 5重量%的铁(II)离子,其百分比基于材料的总量,其中铁氧化物具有改善的耐老化性,特别是关于矫顽力,以及它们的制备方法。