公开(公告)号：US5514468A

公开(公告)日：1996-05-07

申请号：US145173

申请日：1993-11-03

申请人： Hideo Kaneko ,  Katsushi Tokunaga ,  Yoshio Tawara ,  Yoshiaki Shimizu ,  Tadao Nomura

发明人： Hideo Kaneko ,  Katsushi Tokunaga ,  Yoshio Tawara ,  Yoshiaki Shimizu ,  Tadao Nomura

IPC分类号： G11B11/105 ,  B32B3/02 ,  B32B5/16 ,  G11B5/66

CPC分类号： G11B11/10584 ,  G11B11/10593 ,  Y10S428/90 ,  Y10T428/26 ,  Y10T428/265

摘要： A magneto-optical recording medium having a layered structure consisting of a first dielectric layer, magnetic recording layer, second dielectric layer and reflecting layer successively formed on a transparent substrate plate can be imparted with improved performance relative to the recording sensitivity and the C/N ratio when the recording layer and the second dielectric layer each have such a thickness that the angle .delta. given by the equation .delta.=tan.sup.-1 (.epsilon./.theta.k), in which .epsilon. is the Kerr ellipticity of the regenerative light and .theta.k is the Kerr rotation angle, does not exceed 10.degree., the thickness of the recording layer being in the range from 8 nm to 13.5 nm and the thickness of the second dielectric layer satisfying the relationship given by the inequality0.06.ltoreq.nd/.lambda..ltoreq.0.14,in which d is the thickness of the second dielectric layer, .lambda. is the wavelength of the regenerative light for reading-out of the recorded signals and n is the refractive index of the material forming the second dielectric layer to the regenerative light of wavelength .lambda..

摘要翻译： 具有由第一电介质层，磁记录层，第二电介质层和连续形成在透明基板上的反射层组成的层状结构的磁光记录介质可以相对于记录灵敏度和C / N 当记录层和第二介电层各自具有这样的厚度，即由等式delta = tan-1（epsilon /θk）给出的角度δ，其中ε是再生光的Kerr椭圆率和θk是 克尔旋转角不超过10°，记录层的厚度在8nm至13.5nm的范围内，第二介电层的厚度满足不等式0.06

公开(公告)号：US5976271A

公开(公告)日：1999-11-02

申请号：US55822

申请日：1998-04-06

申请人： Tadao Nomura ,  Masaru Ito ,  Ken Ohashi

发明人： Tadao Nomura ,  Masaru Ito ,  Ken Ohashi

IPC分类号： H01F1/057 ,  C21D1/04

CPC分类号： B82Y25/00 ,  H01F1/0571 ,  H01F1/0579 ,  Y10S977/838

摘要： Provided by the invention is a method for the preparation of a magnetically anisotropic permanent magnet mainly consisting of crystallites of the Nd.sub.2 Fe.sub.14 B phase. The method comprises the steps of:(a) preparing an amorphous alloy of neodymium, iron and boron in molar fractions corresponding to the Nd.sub.2 Fe.sub.14 B phase or a nanocomposite of the Nd.sub.2 Fe.sub.14 B/Fe.sub.3 B or Nd.sub.2 Fe.sub.14 B/Fe system, for example, by the melt-spun method; and (b) subjecting the amorphous alloy of neodymium, iron and boron to a heat treatment in a magnetic field of at least 3 T (tesla) at a temperature in the range from 550 to 800.degree. C. for a length of time in the range from 1.times.10.sup.2 to 1.times.10.sup.4 seconds in an atmosphere of a non-reactive gas or vacuum.

摘要翻译： 本发明提供了一种主要由Nd2Fe14B相微晶组成的磁各向异性永磁体的制备方法。 该方法包括以下步骤：（a）制备与Nd 2 Fe 14 B相对应的摩尔分数的钕，铁和硼的非晶合金，或者通过熔融纺丝制备Nd 2 Fe 14 B / Fe 3 B或Nd 2 Fe 14 B / Fe体系的纳米复合材料 方法; 和（b）使钕，铁和硼的非晶合金在至少3T（特斯拉）的磁场中在550-800℃的温度下进行热处理一段时间 在非反应性气体或真空气氛中，范围为1×102-1×104秒。

公开(公告)号：US06589367B2

公开(公告)日：2003-07-08

申请号：US10017387

申请日：2001-12-18

申请人： Tadao Nomura ,  Ken Ohashi

发明人： Tadao Nomura ,  Ken Ohashi

IPC分类号： H01F1053

CPC分类号： B82Y25/00 ,  H01F1/0579 ,  Y10S977/81 ,  Y10S977/838

摘要： Disclosed is a magnetically anisotropic rare earth-based permanent magnet having a nanocomposite structure consisting of fine dispersion of a magnetically hard phase, e.g., Nd2Fe14B, in alignment relative to the easy magnetization axis, a magnetically soft phase and a non-magnetic phase having a melting point lower than those of the magnetically hard and soft phases. The permanent magnet is prepared in a process in which a quenched thin magnet alloy ribbon having a composition capable of forming a magnetically hard phase, magnetically soft phase and non-magnetic phase by a heat treatment is subjected to a heat treatment in a magnetic field of at least 3 T at a temperature not lower than the melting point of the non-magnetic phase so that the liquid phase formed from the non-magnetic phase serves to facilitate rotating orientation of the magnetically hard grains to be aligned in the direction of the magnetic field relative to the easy magnetization axis.

公开(公告)号：US5118573A

公开(公告)日：1992-06-02

申请号：US601659

申请日：1990-10-25

申请人： Yoshio Tawara ,  Katsushi Tokunaga ,  Tadao Nomura ,  Yoshiaki Shimizu ,  Yoshihiro Kubota ,  Meguru Kashida

发明人： Yoshio Tawara ,  Katsushi Tokunaga ,  Tadao Nomura ,  Yoshiaki Shimizu ,  Yoshihiro Kubota ,  Meguru Kashida

IPC分类号： G11B11/105

CPC分类号： G11B11/10586 ,  Y10S428/90

摘要： An improvement is obtained in the stability and recording density of a magneto-optical recording medium having a laminar structure on a transparent substrate plate successively consisting of a first dielectric layer, a magnetic recording layer, a second dielectric layer and a metallic light-reflecting layer by forming the dielectric layer with a unique and specific dielectric material which is an amorphous composite material comprising boron and hydrogen in a specified weight proportion formed by the method of plasma CVD or sputtering. The dielectric material can be a ternary composite of boron, hydrogen and nitrogen or quaternary composite of boron, hydrogen, nitrogen and silicon or carbon.