Magnetic recording medium having a magnetic layer comprising hexagonal
barium ferrite magnetic particles containing tin and magnesium in
specified proportions
    2.
    发明授权
    Magnetic recording medium having a magnetic layer comprising hexagonal barium ferrite magnetic particles containing tin and magnesium in specified proportions 失效
    具有磁性层的磁记录介质包括以规定比例含有锡和镁的六方晶系钡铁氧体磁性颗粒

    公开(公告)号:US5114801A

    公开(公告)日:1992-05-19

    申请号:US571093

    申请日:1990-08-21

    IPC分类号: G11B5/706

    CPC分类号: G11B5/70678 Y10S428/90

    摘要: Disclosed herein is a magnetic recording medium having a magnetic layer comprising hexagonal ferrite magnetic particles each expressed as BaO.multidot.Fe.sub.12-x-y Sn.sub.x Mg.sub.y O.sub.18 (where, 0.55.ltoreq.x.ltoreq.0.88, 0.71.ltoreq.y.ltoreq.1.05). The hexagonal ferrite magnetic particles contained in this magnetic layer each have Sn and Mg partially substituted for Fe, the Sn and Mg being perfectly solid-soluble, thus being capable of providing hexagonal ferrite magnetic particles which are superior in crystalline properties and small in variation of composition. As a result, the coercivity distribution can be made further sensitive, both the self demagnetization and recording demagnetization in the short wave-length range can be reduced, and a higher reproducing output characteristic is attainable in the high density recording range.

    摘要翻译: 本文公开了具有磁性层的磁记录介质,该磁性层包含各自表示为BaO x Fe 12-x-y Sn x M y O 18的六方晶系铁氧体磁性颗粒(其中,0.55≤x≤0.88,0.71≤y≤1.05)。 该磁性层中含有的六方晶系铁氧体磁性粒子各自具有部分地取代Fe的Sn和Mg,Sn和Mg完全固溶,能够提供结晶性优异,变形小的六方晶系铁氧体磁性体 组成。 结果,可以使矫顽力分布更加敏感,可以减少短波长范围内的自消磁和记录退磁,并且在高密度记录范围内可以获得更高的再现输出特性。

    Perpendicular magnetic film of spinel type iron oxide compound and its
manufacturing process
    4.
    发明授权
    Perpendicular magnetic film of spinel type iron oxide compound and its manufacturing process 失效
    尖晶石型氧化铁复合物的垂直磁性膜及其制造工艺

    公开(公告)号:US4975324A

    公开(公告)日:1990-12-04

    申请号:US110852

    申请日:1987-10-21

    摘要: Disclosed herein is a perpendicular magnetic film of spinel type iron oxide formed on a surface of a base substrate in the form of columnar grains which are densely arranged perpendicularly to the surface of the base substrate. A vapor of an organic iron compound or a mixed vapor consisting of the organic iron compound vapor and a vapor of an organic metal compound different from the organic iron compound is added with oxygen to obtain a mixed gas. The mixed gas is subjected to chemical vapor deposition on the substrate at low temperature, at reduced pressure in plasma, thereby to obtain the perpendicular magnetic film.

    摘要翻译: 这里公开了尖晶石型氧化铁的垂直磁性膜,其形成在垂直于基底表面的密实布置的柱状晶体形式的基底基板的表面上。 加入有机铁化合物的蒸气或由有机铁化合物蒸气和不同于有机铁化合物的有机金属化合物的蒸气组成的混合蒸汽,得到混合气体。 混合气体在低温,等离子体中减压下在基板上进行化学气相沉积,得到垂直磁性膜。

    Composite magnetic powder, method for producing the same and recording
medium containing the same
    5.
    发明授权
    Composite magnetic powder, method for producing the same and recording medium containing the same 失效
    复合磁粉,其制造方法和含有该磁粉的记录介质

    公开(公告)号:US4957812A

    公开(公告)日:1990-09-18

    申请号:US107454

    申请日:1987-10-13

    IPC分类号: G11B5/706

    摘要: Disclosed is a composite magnetic powder comprising two crystal phases of a hexagonal ferrite portion and a spinel structure ferrite portion, which are different in thermal characteristic and in crystal structure and which are in a crystallographically epitaxial relation in each particle. The magnetic powder can be synthesized by reaction of starting components in a low temperature solution. Using the magnetic powder, a vertical magnetic recording medium can be provided, which is excellent in weather stability and suitable for short wavelength recording.

    摘要翻译: 公开了一种复合磁粉,其包含六方晶系铁氧体部分和尖晶石结构铁氧体部分的两个结晶相,其热特性和晶体结构不同,并且在每个粒子中具有晶体学外延关系。 磁粉可以通过起始组分在低温溶液中的反应来合成。 使用磁性粉末,可以提供垂直的磁记录介质,其天气稳定性优异并且适合于短波长记录。