公开(公告)号：US5238483A

公开(公告)日：1993-08-24

申请号：US921093

申请日：1992-07-29

申请人： Akio Mishima ,  Mamoru Tanihara ,  Yasutaka Ota ,  Hirofumi Kawasaki ,  Kenji Okinaka ,  Kunio Ikemoto ,  Kousaku Tamari ,  Kohji Mori ,  Norimichi Nagai

发明人： Akio Mishima ,  Mamoru Tanihara ,  Yasutaka Ota ,  Hirofumi Kawasaki ,  Kenji Okinaka ,  Kunio Ikemoto ,  Kousaku Tamari ,  Kohji Mori ,  Norimichi Nagai

IPC分类号： G11B5/706

CPC分类号： G11B5/70615

摘要： Disclosed herein are acicular magnetic iron based alloy particles for magnetic recording, containing 1.5 to 10 mol % of B based on Fe (calculated as B) and 1.5 to 10 mol % of Co based on Fe (calculated as Co) in the vicinity of the surfaces of said particles and having a saturation magnetization of not less than 125 emu/g and an S.F.D. value of not more than 0.50, and a process for producing the same.

摘要翻译： 本文公开了用于磁记录的针状磁性铁基合金颗粒，其含有1.5至10mol％的基于Fe的B（以B计）和1.5至10mol％的基于Fe（以Co计算）的Co在附近 所述颗粒的表面具有不小于125emu / g的饱和磁化强度和SFD 值不大于0.50，及其制造方法。

公开(公告)号：US5156922A

公开(公告)日：1992-10-20

申请号：US728328

申请日：1991-07-08

申请人： Akio Mishima ,  Mamoru Tanihara ,  Yasutaka Ota ,  Hirofumi Kawasaki ,  Kenji Okinaka ,  Kunio Ikemoto ,  Kousaku Tamari ,  Kohji Mori ,  Norimichi Nagai

发明人： Akio Mishima ,  Mamoru Tanihara ,  Yasutaka Ota ,  Hirofumi Kawasaki ,  Kenji Okinaka ,  Kunio Ikemoto ,  Kousaku Tamari ,  Kohji Mori ,  Norimichi Nagai

IPC分类号： G11B5/706

CPC分类号： G11B5/70615 ,  Y10T428/12181

摘要： Disclosed herein are acicular magnetic iron based alloy particles for magnetic recording, containing 1.5 to 10 mol % of B based on Fe (calculated as B) and 1.5 to 10 mol % of Co based on Fe (calculated as Co) in the vicinity of the surfaces of said particles and having a saturation magnetization of not less than 125 emu/g and an S.F.D. value of not more than 0.50, and a process for producing the same.

公开(公告)号：US5466306A

公开(公告)日：1995-11-14

申请号：US118287

申请日：1993-09-09

申请人： Akio Mishima ,  Tosiharu Harada ,  Mamoru Tanihara ,  Yasutaka Ota ,  Kenji Okinaka ,  Kohji Mori ,  Hirofumi Kawasaki ,  Norimichi Nagai ,  Katsunori Fujimoto ,  Yoshiro Okuda

发明人： Akio Mishima ,  Tosiharu Harada ,  Mamoru Tanihara ,  Yasutaka Ota ,  Kenji Okinaka ,  Kohji Mori ,  Hirofumi Kawasaki ,  Norimichi Nagai ,  Katsunori Fujimoto ,  Yoshiro Okuda

IPC分类号： G11B5/706 ,  G11B5/714 ,  H01F1/06

CPC分类号： G11B5/70621 ,  G11B5/70615 ,  G11B5/714 ,  H01F1/061

摘要： Disclosed herein are spindle-shaped magnetic iron based alloy particles containing at least one selected from the group consisting of Ni, Al, Si, P, Co, Mg, B and Zn, which have a particle length of 0.05 to 0.40 .mu.m, a crystallite size of 110 to 180 .ANG., a specific surface area of 30 to 60 m.sup.2 /g, a coercive force of 1,300 to 1,700 Oe and a saturation magnetization (.sigma.s) of not less than 100 emu/g and a process for producing the same.

摘要翻译： 本文公开了含有选自Ni，Al，Si，P，Co，Mg，B和Zn中的至少一种的锭状磁铁基合金粒子，其粒径为0.05〜0.40μm，a 微晶尺寸为110〜180，比表面积为30〜60m2 / g，矫顽力为1300〜1700Oe，饱和磁化强度（sigma）为100emu / g以上， 相同。

公开(公告)号：US5599378A

公开(公告)日：1997-02-04

申请号：US450205

申请日：1995-05-25

申请人： Akio Mishima ,  Tosiharu Harada ,  Mamoru Tanihara ,  Yasutaka Ota ,  Kenji Okinaka ,  Kohji Mori ,  Hirofumi Kawasaki ,  Norimichi Nagai ,  Katsunori Fujimoto ,  Yoshiro Okuda

发明人： Akio Mishima ,  Tosiharu Harada ,  Mamoru Tanihara ,  Yasutaka Ota ,  Kenji Okinaka ,  Kohji Mori ,  Hirofumi Kawasaki ,  Norimichi Nagai ,  Katsunori Fujimoto ,  Yoshiro Okuda

IPC分类号： G11B5/706 ,  G11B5/714 ,  H01F1/06 ,  H01F1/11 ,  H01F1/36

CPC分类号： G11B5/70621 ,  G11B5/70615 ,  G11B5/714 ,  H01F1/061

摘要： Disclosed herein are spindle-shaped magnetic iron based alloy particles containing at least one selected from the group consisting of Ni, Al, Si, P, Co, Mg, B and Zn, which have a particle length of 0.05 to 0.40 .mu.m, a crystallite size of 110 to 180 .ANG., a specific surface area of 30 to 60 m.sup.2 /g, a coercive force of 1,300 to 1,700 Oe and a saturation magnetization (.sigma.s) of not less than 100 emu/g and a process for producing the same.

摘要翻译： 本文公开了含有选自Ni，Al，Si，P，Co，Mg，B和Zn中的至少一种的锭状磁铁基合金粒子，其粒径为0.05〜0.40μm，a 微晶尺寸为110〜180，比表面积为30〜60m2 / g，矫顽力为1300〜1700Oe，饱和磁化强度（sigma）为100emu / g以上， 相同。

公开(公告)号：US5531922A

公开(公告)日：1996-07-02

申请号：US527017

申请日：1995-09-12

申请人： Kenji Okinaka ,  Yasutaka Ota ,  Kohji Mori ,  Hirofumi Kawasaki ,  Masayuki Uegami ,  Akio Mishima ,  Katsumi Yamashita ,  Minoru Yamasaki ,  Manabu Matsumoto ,  Kunihiro Kouchi ,  Hiroki Kamon

发明人： Kenji Okinaka ,  Yasutaka Ota ,  Kohji Mori ,  Hirofumi Kawasaki ,  Masayuki Uegami ,  Akio Mishima ,  Katsumi Yamashita ,  Minoru Yamasaki ,  Manabu Matsumoto ,  Kunihiro Kouchi ,  Hiroki Kamon

IPC分类号： G11B5/706 ,  G11B5/714 ,  H01F1/06 ,  C01G49/02

CPC分类号： G11B5/714 ,  G11B5/70647 ,  H01F1/061

摘要： Disclosed herein are granulated particles for magnetic particles for magnetic recording, comprising: acicular ferric hydroxide oxide particles or acicular iron oxide particles; and at least one selected from the group consisting of semisynthetic starch and semisynthetic cellulose and having a bulk density of not less than 0.3 g/cm.sup.3 and a powdering ratio of not more than 40%, and a process for producing the granulated particles, and magnetic particles obtained from such granulated particles.

摘要翻译： 本文公开了用于磁记录的磁性颗粒的造粒颗粒，包括：针状氧化铁氧化物颗粒或针状氧化铁颗粒; 以及选自由半合成淀粉和半合成纤维素组成的组中的至少一种，其堆积密度不小于0.3g / cm 3，粉化比不大于40％，以及制备造粒颗粒的方法和磁性 从这种造粒颗粒获得的颗粒。

公开(公告)号：US5735969A

公开(公告)日：1998-04-07

申请号：US612517

申请日：1996-03-07

申请人： Jean A. Lown ,  Yasutaka Ota ,  Kenji Okinaka ,  Hirofumi Kawasaki

发明人： Jean A. Lown ,  Yasutaka Ota ,  Kenji Okinaka ,  Hirofumi Kawasaki

IPC分类号： B22F9/22 ,  B22F1/02 ,  C22C38/00 ,  C22C38/10 ,  G11B5/706 ,  G11B5/712 ,  H01F1/06 ,  H01F1/03

CPC分类号： G11B5/70621 ,  G11B5/712 ,  H01F1/061 ,  H01F1/065

摘要： The present invention is a method for making highly stable magnetic alloy particles with high coercivities and high saturation magnetization comprising the steps of: a) providing a precursor selected from the group consisting of iron oxide hydroxide particles and iron oxide particles, wherein the precursor particle comprises from about 15 to about 45 atomic % Co based on amount of Fe present, b) reducing the precursor particles to magnetic alloy particles, c) passivating the magnetic alloy particles in an oxygen-containing atmosphere at a temperature between about 20.degree. and 100.degree. C., d) annealing the passivated magnetic alloy particles in an inert atmosphere at a temperature from about 120.degree. to about 450.degree. C., and e) further oxidizing the annealed magnetic alloy particles in an oxygen-containing atmosphere.

摘要翻译： 本发明是制备具有高矫顽力和高饱和磁化强度的高度稳定的磁性合金颗粒的方法，包括以下步骤：a）提供选自铁氧化物氢氧化物颗粒和氧化铁颗粒的前体，其中前体颗粒包含 约15〜约45原子％Co，b）将前体粒子还原成磁性合金粒子，c）在约20〜100℃的温度下使含氧气氛中的磁性合金粒子钝化 c）d）在约120℃至约450℃的温度下在惰性气氛中退火钝化的磁性合金颗粒，和e）在含氧气氛中进一步氧化退火的磁性合金颗粒。

公开(公告)号：US5645652A

公开(公告)日：1997-07-08

申请号：US433871

申请日：1995-05-01

申请人： Kenji Okinaka ,  Yasutaka Ota

发明人： Kenji Okinaka ,  Yasutaka Ota

IPC分类号： B22F1/00 ,  C01G49/06 ,  G11B5/706 ,  B22F9/26 ,  H01F1/20

CPC分类号： B82Y30/00 ,  B22F1/004 ,  C01G49/06 ,  G11B5/70621 ,  C01P2002/54 ,  C01P2002/60 ,  C01P2004/03 ,  C01P2004/10 ,  C01P2004/54 ,  C01P2004/62 ,  C01P2004/64 ,  C01P2004/84 ,  C01P2006/42 ,  Y10T428/12097 ,  Y10T428/12181

摘要： The disclosure describes spindle-shaped magnetic iron-based alloy particles containing cobalt and iron as the main ingredients in which the Co content is 1.0 to 50.0 atm % (calculated as Co) based on the total Fe in the spindle-shaped magnetic iron-based alloy particles, and which the spindle-shaped magnetic iron-based alloy particles have an average major axis diameter of 0.05 to 0.18 .mu.m, a size distribution (standard deviation/major axis diameter) of not more than 0.25, an average minor axis diameter of 0.010 to 0.020 .mu.m, an aspect ratio (major axis diameter/minor axis diameter) of 4 to 15, an X-ray crystallite size D.sub.110 of 120 to 180 .ANG., a coercive force of 1720 to 2500 Oe, a saturation magnetization of not less than 110 emu/g, and a saturation magnetization decrement percentage of not more than 17%.

摘要翻译： 本发明描述了以钴和铁为主要成分的纺锤形磁性铁基合金颗粒作为主要成分，其中Co含量为1.0至50.0atm％（以Co计算），基于纺锤形磁性铁基中的总Fe 合金颗粒，并且纺锤形磁性铁基合金颗粒的平均长轴直径为0.05至0.18μm，尺寸分布（标准偏差/长轴直径）不大于0.25，平均短轴直径 为0.010〜0.020μm，长宽比（长轴径/短轴直径）为4〜15，X射线晶粒尺寸D110为120〜180，矫顽力为1720〜2500Oe，饱和磁化强度为 不小于110emu / g，饱和磁化强度减少百分比不大于17％。

公开(公告)号：US06753084B2

公开(公告)日：2004-06-22

申请号：US10022801

申请日：2001-12-20

申请人： Masaaki Maekawa ,  Haruki Kurokawa ,  Kenji Okinaka ,  Akinori Yamamoto ,  Yasutaka Ota

发明人： Masaaki Maekawa ,  Haruki Kurokawa ,  Kenji Okinaka ,  Akinori Yamamoto ,  Yasutaka Ota

IPC分类号： B32B516

CPC分类号： G11B5/70621 ,  Y10S428/90

摘要： Spindle-shaped magnetic alloy particles containing Fe and Co as main components of the present invention have a cobalt content of 20 to 50 atm % (calculated as Co) based on whole Fe; an average major axis diameter (L) of 0.03 to 0.10 &mgr;m; a coercive force value of 159.2 to 238.7 kA/m (2,000 to 3,000 Oe); a crystallite size of 100 to 160 Å; and an activation volume (Vact) of 0.01 to 0.07E-4 &mgr;m3. A high-density magnetic recording medium produced by using such spindle-shaped magnetic alloy particles containing Fe and Co as main components, have an excellent output characteristics in a short wavelength region, a considerably reduced noise and an excellent storage stability.

摘要翻译： 含有Fe和Co作为本发明主要成分的锭状磁性合金颗粒的钴含量基于Fe的总和为20〜50atm％（以Co计）。 平均长轴直径（L）为0.03〜0.10μm; 矫顽力值为159.2〜238.7kA / m（2,000〜3,000Oe）; 微晶尺寸为100至160埃; 和活性体积（Vact）为0.01〜0.07E-4mum 3。 通过使用含有Fe和Co作为主要成分的纺锤形磁性合金粒子制造的高密度磁记录介质，在短波长区域具有优异的输出特性，噪音明显降低，存储稳定性优异。

公开(公告)号：US5989516A

公开(公告)日：1999-11-23

申请号：US986630

申请日：1997-12-08

申请人： Kenji Okinaka ,  Yasutaka Ota

发明人： Kenji Okinaka ,  Yasutaka Ota

IPC分类号： B22F1/00 ,  C01G49/06 ,  G11B5/706 ,  C01G49/02

CPC分类号： B82Y30/00 ,  B22F1/004 ,  C01G49/06 ,  G11B5/70621 ,  C01P2002/54 ,  C01P2002/60 ,  C01P2004/03 ,  C01P2004/10 ,  C01P2004/54 ,  C01P2004/62 ,  C01P2004/64 ,  C01P2004/84 ,  C01P2006/42

摘要： The present invention relates to a spindle-shaped goethite particles containing cobalt of 8.0 to 50.0 atm %, calculated as Co, based on the total Fe in the spindle-shaped goethite particles and a compound of at least one element selected from the group consisting of Al, Si, Nd, Y, La, Ce, Pr, Tb, Ca, Mg, Ba and Sr of not more than 25.0 atm %, calculated as the element, based on the total Fe in the spindle-shaped goethite particles, and having an average major axis diameter of 0.05 to 0.15 .mu.m, a size distribution (standard deviation/major axis diameter) of not more than 0.30, an average minor axis diameter of 0.010 to 0.025 .mu.m, an aspect ratio of 4 to 8 and an X-ray crystallite size ratio (D.sub.020 /D.sub.110) of 2.0 to 3.5. These spindle-shaped goethite particles are useful as raw material of spindle-shaped magnetic iron-based alloy particles containing cobalt and iron as the main ingredients, which have a uniform particle size, no inclusion of dendrites, a high coercive force, an excellent coercive force distribution, a large saturation magnetization, and in addition, an excellent stability against oxidation.

摘要翻译： 本发明涉及一种纺锤形针铁矿颗粒，其中钴为8.0〜50.0atm％，以Co计算，基于纺锤状针铁矿颗粒中的Fe总量和选自以下的至少一种元素的化合物： Al，Si，Nd，Y，La，Ce，Pr，Tb，Ca，Mg，Ba和Sr的含量以不超过25.0atm％计，作为元素，基于纺锤形针铁矿颗粒中的总Fe， 平均长轴直径为0.05〜0.15μm，尺寸分布（标准偏差/长轴直径）不大于0.30，平均短轴直径为0.010至0.025μm，纵横比为4至8和 X射线微晶尺寸比（D020 / D110）为2.0〜3.5。 这些纺锤状针铁矿颗粒可用作以钴和铁为主要成分的纺锤形磁性铁基合金颗粒的原料，它们具有均匀的粒度，不包括枝晶，高矫顽力，优良的矫顽力 力分布，饱和磁化强度大，另外还具有优异的抗氧化稳定性。

公开(公告)号：US5968226A

公开(公告)日：1999-10-19

申请号：US777905

申请日：1996-12-31

申请人： Kenji Okinaka ,  Yasutaka Ota

发明人： Kenji Okinaka ,  Yasutaka Ota

IPC分类号： B22F1/00 ,  C01G49/06 ,  G11B5/706 ,  H01F1/11 ,  H01F1/36

CPC分类号： B82Y30/00 ,  B22F1/004 ,  C01G49/06 ,  G11B5/70621 ,  C01P2002/54 ,  C01P2002/60 ,  C01P2004/03 ,  C01P2004/10 ,  C01P2004/54 ,  C01P2004/62 ,  C01P2004/64 ,  C01P2004/84 ,  C01P2006/42 ,  Y10T428/12097 ,  Y10T428/12181

摘要： The disclosure describes spindle-shaped magnetic iron-based alloy particles containing cobalt and iron as the main ingredients in which the Co content is 1.0 to 50.0 atm % (calculated as Co) based on the total Fe in the spindle-shaped magnetic iron-based alloy particles, and which the spindle-shaped magnetic iron-based alloy particles have an average major axis diameter of 0.05 to 0.18 .mu.m, a size distribution (standard deviation/major axis diameter) of not more than 0.25, an average minor axis diameter of 0.010 to 0.020 .mu.m, an aspect ratio (major axis diameter/minor axis diameter) of 4 to 15, an X-ray crystallite size D.sub.110 of 120 to 180 .ANG., a coercive force of 1720 to 2500 Oe, a saturation magnetization of not less than 110 emu/g, and a saturation magnetization decrement percentage of not more than 17%.

摘要翻译： 本发明描述了以钴和铁为主要成分的纺锤形磁性铁基合金颗粒作为主要成分，其中Co含量为1.0至50.0atm％（以Co计算），基于纺锤形磁性铁基中的总Fe 合金颗粒，并且纺锤形磁性铁基合金颗粒的平均长轴直径为0.05至0.18μm，尺寸分布（标准偏差/长轴直径）不大于0.25，平均短轴直径 为0.010〜0.020μm，长宽比（长轴径/短轴直径）为4〜15，X射线晶粒尺寸D110为120〜180，矫顽力为1720〜2500Oe，饱和磁化强度为 不小于110emu / g，饱和磁化强度减少百分比不大于17％。