公开(公告)号：US5698336A

公开(公告)日：1997-12-16

申请号：US629766

申请日：1996-04-09

申请人： Minoru Hashimoto ,  Tatsumi Maeda ,  Masahiro Fukasawa ,  Kazutaka Akiyama ,  Tsutomu Tanaka

发明人： Minoru Hashimoto ,  Tatsumi Maeda ,  Masahiro Fukasawa ,  Kazutaka Akiyama ,  Tsutomu Tanaka

IPC分类号： G11B5/706 ,  G11B5/66

CPC分类号： G11B5/70678 ,  Y10S428/90

摘要： A magnetic recording medium is disclosed, which has a magnetic layer containing a hexagonal ferrite powder dispersed in a resin binder, the magnetic layer being formed on a nonmagnetic supporting substrate, wherein the hexagonal ferrite powder is a compound represented by the following chemical formula AO.2 (M.sup.1 0).Fe.sub.16-x M.sup.2.sub.x 0.sub.24 where A is at least one element selected from the group consisting of Ba, Sr, Ca, and Pb; M.sup.1 is at least one element selected from the group consisting of Zn, Ni and Co; M.sup.2 is one combination selected from the group consisting of a combination of two elements of Co and Ti, a combination of two elements of Ti and Zn, and a combination of three elements of Co, Ti and Zn; and x designates a number in the range from 0.6 to 3.0, the hexagonal ferrite powder having an average diameter/thickness ratio in the range from 2.0 to 5.0; the magnetic recording medium of the present invention has both resistance to the temporary variation of coercive force caused by a fluctuation of environmental temperatures and resistance to the permanent variation of the coercive force resulting from a long time storage and operation.

摘要翻译： 公开了一种磁记录介质，其具有包含分散在树脂粘合剂中的六方铁氧体粉末的磁性层，所述磁性层形成在非磁性支撑基板上，其中所述六方晶系铁氧体粉末是由以下化学式AO.2表示的化合物 （M10）Fe16-xM2x024其中A是选自Ba，Sr，Ca和Pb中的至少一种元素; M1是选自Zn，Ni和Co中的至少一种元素; M2是选自Co和Ti的两种元素的组合，Ti和Zn的两种元素的组合以及Co，Ti和Zn的三种元素的组合的组合的组合; x表示0.6〜3.0的数值，平均直径/厚度比在2.0〜5.0的六角铁氧体粉末; 本发明的磁记录介质既具有由于环境温度变动引起的矫顽力的暂时变化的抵抗性，并且耐长时间保存和操作导致的矫顽力的永久性变化。

公开(公告)号：US4606971A

公开(公告)日：1986-08-19

申请号：US639317

申请日：1984-08-10

申请人： Tadashi Ido ,  Osamu Kubo ,  Masahiro Fukasawa ,  Tatsumi Maeda ,  Tutomu Nomura

发明人： Tadashi Ido ,  Osamu Kubo ,  Masahiro Fukasawa ,  Tatsumi Maeda ,  Tutomu Nomura

IPC分类号： G11B5/706 ,  C09D5/23 ,  C09D7/12 ,  G11B5/70 ,  G11B5/714

CPC分类号： G11B5/714 ,  Y10S428/90 ,  Y10T428/256 ,  Y10T428/257

摘要： Disclosed is a magnetic recording medium comprised of a substrate and a layer of magnetic powder coated on a surface of the substrate, characterized in that the magnetic powder is hexagonal crystals having single domain crystalline magnetic anisotropy, particle sizes of 0.01 to 0.3 .mu.m, particle size/thickness ratios of 2.3 to 15 and the tapping packing rate of said magnetic powder is 15% or more.

摘要翻译： 公开了一种磁性记录介质，由基材和涂覆在基材表面上的一层磁粉组成，其特征在于，磁粉是具有单结晶磁各向异性的六方晶体，粒径为0.01〜0.3μm，粒径为 尺寸/厚度比为2.3至15，所述磁粉的攻丝包装率为15％以上。