摘要:
A magnetic powder for magnetic recording is disclosed which comprises composite magnetic particles (A), each of which contains hexagonal ferrite and spinel structure ferrite, and single phase magnetic particles of hexagonal ferrite (B). When the mixing ratio [(A):(B)] of (A) and (B) in the range from 5:95 to 95:5, remarkable effect can be obtained. Especially, when the mixing ratio of (A) and (B) is in the range from 5:95 to 30:70, the dispersion property is improved due to disturbance of magnetic stacking. Thus, the magnetic powder in this mixing ratio is particularly suitable for magnetic recording in a short wavelength range. When the mixing ratio of (A) and (B) is in the range from 70:30 to 95:5, the reproduction output is improved due to activation of (A). Thus, the magnetic powder in this mixing ratio is specifically suitable for magnetic recording in a long wavelength range. By containing the magnetic powder described above, a perpendicular magnetic recording medium with high electromagnetic characteristics, particularly a high S/N ratio and a low noise can be obtained.
摘要:
A magnetic powder for magnetic recording is disclosed which comprises composite type magnetic particles (A), each of which contains hexagonal ferrite and spinel structure ferrite, and single phase type magnetic particles of hexagonal ferrite (B). When the mixing ratio of (A) and (B) in the range from 5:95 to 95:5, remarkable effect can be obtained. Especially, when the mixing ratio of (A) and (B) is in the range from 5:95 to 30:70, the dispersion property is improved due to disturbance of magnetic stacking. Thus, the magnetic powder in this mixing ratio is particularly suitable for magnetic recording in a short wavelength range. When the mixing ratio of (A) and (B) is in the range 70: 30 to 95:5, the reproduction output is improved due to activation of (A) . Thus, the magnetic powder in this mixing ratio is specifically suitable for magnetic recording in a long wavelength range. By containing the magnetic powder described above, a perpendicular magnetic recording medium with high electromagnetic characteristics, particularly a high S/N ratio and a low noise can be obtained.
摘要:
A magnetic powder is disclosed which is characterized by possessing a powder compression characteristic such that the magnetic powder, after being packed in a closed container, pressed at a load of 400 kgf/cm.sup.3, and relieved of the load, exhibits a packing density in the range of 2.5 to 3.5 g/cm.sup.3 and a geometric standard deviation of not more than 1.5 in the particle diameter distribution. A magnetic recording medium using the magnetic powder mentioned above has high packing and, consequently, secures high output, and has ample diminution of noise.
摘要翻译:公开了一种磁粉,其特征在于具有粉末压缩特性,使得磁粉在被包装在密闭容器中之后,以400kgf / cm 3的负荷压下并释放负载,表现出在 范围为2.5〜3.5g / cm3,粒径分布的几何标准偏差为1.5以下。 使用上述磁粉的磁记录介质具有高填充性,因此确保高输出,并且噪声大大降低。
摘要:
An object of the present invention is to provide a magnetic powder for magnetic recording and a magnetic recording medium wherein stability of a coercive force of each of the magnetic powder and the magnetic recording medium is improved. The magnetic powder for magnetic recording and the magnetic recording medium having the magnetic powder used therfor are characterized in that the magnetic powder is composed mainly of a plate-shaped ferrite having a crystalline anisotropy and containing an element effective for reducing a temperature coefficient of coercive force of the magnetic powder, and that a difference between a coercive force (Hc) of the magnetic powder at a room temperature and a coercive force (Hc(s)) of the magnetic powder in such a state that the magnetic powder is dispersively deposited on the surface of silica (SiO.sub.2) powder particles is 100 (Oe) or less.
摘要:
A magnetic powder is disclosed which is characterized by possessing a powder compression characteristic such that the magnetic powder, after being packed in a closed container, pressed at a load of 400 kgf/cm.sup.3 and relieved of the load, exhibits a packing density in the range of 2.5 to 3.5 g/cm.sup.3 and a geometric standard deviation of not more than 1.5 in the particle diameter distribution. A magnetic recording medium using the magnetic powder mentioned above has high packing and, consequently, secures high output, and has ample diminution of noise.
摘要翻译:公开了一种磁粉,其特征在于具有粉末压缩特性,使得磁粉在被包装在密闭容器中,以400kgf / cm 3的负荷压载并释放负载后,表现出在该范围内的堆积密度 为2.5〜3.5g / cm3,粒径分布的几何标准偏差为1.5以下。 使用上述磁粉的磁记录介质具有高填充性,因此确保高输出,并且噪声大大降低。
摘要:
A hexagonal ferrite magnetic powder for high density magnetic recording, having an improved dispersibility in a binder or paint is obtained by melting a mixture of hexagonal ferrite-forming components and a glass-forming component, and rapidly cooling the resultant molten mixture to obtain an amorphous material. The amorphous material is thermally treated to precipitate fine particles of the hexagonal ferrite therein. The amorphous material containing the precipitated fine particles is dissolved such that the glass-forming component remains on each of said fine particles in an amount of 0.01 to 0.3% by weight based on the weight of the particles.
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:
A matnetic recording powder comprising a hexagonal barium ferrite substituted with a coercive force control element. This magnetic powder is preliminarily treated with sulfate ion-containing water so as to convert any free barium ions in the magnetic powder to a water insoluble compound such as BaSO.sub.4 or BaS.sub.2 O.sub.7. There is also proposed a magnetic recording medium having a magnetic layer containing such a magnetic powder as mentioned above.
摘要翻译:一种包含被矫顽力控制元件取代的六方晶系钡铁氧体的生物记录粉末。 该磁性粉末用含硫酸根离子的水预先处理,以将磁性粉末中的任何游离的钡离子转化为不溶于水的化合物如BaSO 4或BaS 2 O 7。 还提出了具有如上所述的含有这种磁性粉末的磁性层的磁记录介质。
摘要:
A magnetic recording powder comprising a hexagonal barium ferrite substituted with a coercive force control element. This magnetic powder is preliminarily treated with sulfate ion-containing water so as to convert any free barium ions in the magnetic powder to a water insoluble compound such as BaSO.sub.4 or BaS.sub.2 O.sub.7. There is also proposed a magnetic recording medium having a magnetic layer containing such a magnetic powder as mentioned above.
摘要:
Disclosed is a silicon nitride sintered body comprising 85 to 99 mole % of .beta.-Si.sub.3 N.sub.4, 1 to 5 mole % as the oxide (M.sub.2 O.sub.3) of at least one compound of an element (M) selected from the group consisting of Sc, Vb, Er, Ho and Dy and less than 10 mole % of excessive oxygen (O.sub.2) based on the three components, wherein the excessive oxygen/M.sub.2 O.sub.3 molar ratio is lower than 2.
摘要翻译:公开了一种氮化硅烧结体,其包含85至99摩尔%的β-Si 3 N 4,1至5摩尔%的至少一种元素(M)的化合物的氧化物(M 2 O 3),其选自Sc,Vb, Er,Ho和Dy,并且基于三种组分小于10摩尔%的过量氧(O 2),其中过量的氧/ M 2 O 3摩尔比低于2。