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:
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 powder for a magnetic recording medium comprising a plurality of magnetic particles and a coating covering the surfaces of the magnetic particles. The coating is a residue resulting from the thermal decomposition of an organic material. The powder is manufactured by applying one or more organic materials to the surfaces of a plurality of magnetic particles by dispersing the magnetic particles in a solution containing the organic material. The magnetic particles, having the organic material as a coating, are separated from the solution, and the magnetic particles are heated to a temperature at which the organic material decomposes.
摘要:
A magnetic recording medium in which a hexagonal crystalline system ferromagnetic powder having a specific surface area of 25 to 50 m.sup.2 /g is dispersed in a resinous binder is suitable for high-density recording which is low in noise and is excellent in orientation properties.
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 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:
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:
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:
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。
摘要:
A molding method of ceramic body comprising the following steps of:preparing a ceramic slurry by adding, to ceramic raw material powders, a solvent, organic dispersant and caking agent and mixing them altogether; casting said ceramic slurry into a mold; cooling it to a temperature lower than the melting point of said caking agent; and taking it out of the mold.This molding method is capable of dissolving cracking generation during releasing the ceramic body from a mold, facilitating machining, decreasing the binder amount of organic compounds, diminishing a firing shrinkage and obtaining a higher dimension accuracy.