公开(公告)号：US5114801A

公开(公告)日：1992-05-19

申请号：US571093

申请日：1990-08-21

申请人： Nobuyuki Aoki ,  Keiichi Ochiai ,  Hideaki Komoda

发明人： Nobuyuki Aoki ,  Keiichi Ochiai ,  Hideaki Komoda

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。

公开(公告)号：US4886714A

公开(公告)日：1989-12-12

申请号：US192051

申请日：1988-05-09

申请人： Hideo Torii ,  Masaki Aoki ,  Hideaki Komoda ,  Nobuyuki Aoki ,  Ikuo Ota ,  Keiichi Ochiai

发明人： Hideo Torii ,  Masaki Aoki ,  Hideaki Komoda ,  Nobuyuki Aoki ,  Ikuo Ota ,  Keiichi Ochiai

IPC分类号： C01G49/00 ,  G11B5/706 ,  H01F1/11

CPC分类号： G11B5/70678

摘要： The present invention provides a platelike magnetic powder made from a magnetic powder having particles each of which has a portion comprising the spinel type crystal structure and a portion comprising the magnetoplumbite type crystal structure. The magnetic powder provides a large saturation magnetization .sigma.s and a small temperature change .DELTA.Hc/.DELTA.T of coercive force in the vicinity of the room temperature. Further, the present invention is to provide a high density magnetic recording medium which uses the magnetic powder. Furthermore, the present invention is to provide, a method to easily manufacture the magnetic powder by the coprecipitation method. A raw material powder of superfine particles is prepared. The prepared powder is fired at a low temperature in a non-oxidizing atmosphere.

公开(公告)号：US5501896A

公开(公告)日：1996-03-26

申请号：US308967

申请日：1994-09-20

申请人： Yasuhiro Ueyama ,  Keiichi Ochiai ,  Tetsuo Satake ,  Hideaki Komoda ,  Hideo Hatanaka

发明人： Yasuhiro Ueyama ,  Keiichi Ochiai ,  Tetsuo Satake ,  Hideaki Komoda ,  Hideo Hatanaka

IPC分类号： G11B5/735 ,  G11B5/738 ,  B32B5/16 ,  G11B5/66

CPC分类号： G11B5/738 ,  G11B5/735 ,  Y10S428/90 ,  Y10T428/25 ,  Y10T428/257 ,  Y10T428/2982 ,  Y10T428/2998

摘要： In the magnetic recording medium, the non-magnetic substrate has an under-coat layer including the first flake powder of non-magnetic material on its surface and further has a back-coat film including the second flake powder of non-magnetic material on the opposite face on the non-magnetic substrate to the one face coated by the magnetic film; thereby splendid property of running durability and electromagnetic transducing characteristics is achieved in spite of thinning the total thickness of the magnetic recording medium.

摘要翻译： 在磁记录介质中，非磁性基板的表面具有包含非磁性材料的第一片状粉末的底涂层，并且还具有包含非磁性材料的第二片状粉末的背涂膜 在非磁性基板上的相对面到由磁性膜涂覆的一面; 尽管磁记录介质的总厚度变薄，但是实现了运行耐久性和电磁转换特性的辉煌性能。

公开(公告)号：US4975324A

公开(公告)日：1990-12-04

申请号：US110852

申请日：1987-10-21

申请人： Hideo Torii ,  Eiji Fujii ,  Masaki Aoki ,  Nobuyuki Aoki ,  Keiichi Ochiai

发明人： Hideo Torii ,  Eiji Fujii ,  Masaki Aoki ,  Nobuyuki Aoki ,  Keiichi Ochiai

IPC分类号： C23C16/40 ,  C23C16/507 ,  G11B5/64 ,  G11B5/85

CPC分类号： G11B5/85 ,  C23C16/406 ,  C23C16/507 ,  G11B5/64 ,  Y10S428/90 ,  Y10T428/257

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。

公开(公告)号：US4957812A

公开(公告)日：1990-09-18

申请号：US107454

申请日：1987-10-13

申请人： Nobuyuki Aoki ,  Masaki Aoki ,  Hideo Torii ,  Keiichi Ochiai ,  Eiji Fujii

发明人： Nobuyuki Aoki ,  Masaki Aoki ,  Hideo Torii ,  Keiichi Ochiai ,  Eiji Fujii

IPC分类号： G11B5/706

CPC分类号： G11B5/70678 ,  Y10S428/90 ,  Y10T428/257

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。