公开(公告)号：US4495164A

公开(公告)日：1985-01-22

申请号：US512661

申请日：1983-07-11

申请人： Yosiro Okuda ,  Tosiharu Harada

发明人： Yosiro Okuda ,  Tosiharu Harada

IPC分类号： C01G49/06 ,  C01G49/08 ,  G11B5/706

CPC分类号： C01G49/06 ,  C01G49/08 ,  G11B5/70678 ,  C01P2004/03 ,  C01P2004/10 ,  C01P2004/54 ,  C01P2004/61 ,  C01P2004/62 ,  C01P2006/42

摘要： A process for producing acicular magnetite or maghemite of high axial ratio, which comprisespreparing an iron (II) hydroxide suspension at a pH of at least 11 with a magnesium sulfate or magnesium chloride in an amount of 0.5 to 7.0 atomic % based on the amount of the iron (II) hydroxide in the suspension and calculated as the ratio of Mg to Fe (II),oxidizing the resultant suspension with the oxygen-containing gas to form an acicular iron (III) oxide hydroxide in the form of particles having a long axis length of 0.3 to 2.0 .mu.m and an axial ratio of more than 20:1,reducing said acicular iron (III) oxide hydroxide into the acicular magnetite, and oxidizing the resultant acicular magnetite to form the acicular maghemite, if necessary.

摘要翻译： 一种制备高轴比的针状磁铁矿或磁赤铁矿的方法，其包括以0.5至7.0原子％的量以硫酸镁或氯化镁制备pH至少为11的氢氧化铁（II）悬浮液， 的悬浮液中的氢氧化铁（II），并以Mg与Fe（II）的比例计算，用含氧气体氧化所得的悬浮液，形成具有下列物质的颗粒形式的针状（III）氧化物氢氧化物 长轴长度为0.3〜2.0μm，轴比为20:1以上，将针状铁氧化物氢氧化物还原成针状磁铁矿，并根据需要氧化所得针状磁铁矿以形成针状磁赤铁矿。

公开(公告)号：US4406694A

公开(公告)日：1983-09-27

申请号：US285983

申请日：1981-07-23

申请人： Akio Mishima ,  Yosiro Okuda ,  Tosiharu Harada ,  Akira Mukaizaka

发明人： Akio Mishima ,  Yosiro Okuda ,  Tosiharu Harada ,  Akira Mukaizaka

IPC分类号： G11B5/62 ,  B22F1/00 ,  B22F9/22 ,  C09D5/23 ,  C09D7/12 ,  C22C38/00 ,  H01F1/06 ,  B22F1/02 ,  B22F9/18

CPC分类号： H01F1/065

摘要： A process for producing an acicular ferromagnetic alloy particles mainly containing iron and magnesium, which comprises preparing a suspension of iron(II) hydroxide and water-soluble magnesium salt, the suspension having a pH value of at least 11 and containing the magnesium salt in an amount of 0.5 to 20.0 atomic % based on the amount of the iron(II) hydroxide in the suspension and calculated as the ratio of Mg to Fe(II), oxidizing the suspension with an oxygen-containing gas to form an acicular particles of iron(III) oxide hydroxide substituted with magnesium, forming coats of phosphorus compound and subsequent silicon compound on the acicular particles, heating the resultant particle at 500.degree. to 900.degree. C. under a non-reducing atmosphere and then reheating the particle thus treated at 350.degree. to 600.degree. C. under reducing atmosphere.

摘要翻译： 一种主要含铁和镁的针状铁磁性合金颗粒的制造方法，包括制备氢氧化铁（II）和水溶性镁盐的悬浮液，所述悬浮液的pH值至少为11，并含有镁盐 相对于悬浮液中的氢氧化铁（II）的量为0.5〜20.0原子％，以Mg与Fe（II）的比例计算，用含氧气体氧化悬浮液，形成针状的铁粒子 （III）氧化物氢氧化物，用镁取代，在针状颗粒上形成磷化合物和随后的硅化合物的涂层，在非还原气氛下在500-900℃下加热所得颗粒，然后在350℃下再加热处理的颗粒 在还原气氛下，温度为600℃。

公开(公告)号：US4773931A

公开(公告)日：1988-09-27

申请号：US8113

申请日：1987-01-23

申请人： Akio Mishima ,  Yosiro Okuda ,  Hiroshi Sumita ,  Yoshitaka Yoshinaga ,  Akira Mukaizaka ,  Tokihiro Kurata

发明人： Akio Mishima ,  Yosiro Okuda ,  Hiroshi Sumita ,  Yoshitaka Yoshinaga ,  Akira Mukaizaka ,  Tokihiro Kurata

IPC分类号： B22F9/22 ,  C22C33/02 ,  G11B5/706 ,  H01F1/06 ,  B22F1/00

CPC分类号： B22F9/22 ,  C22C33/0257 ,  G11B5/70615 ,  H01F1/065

摘要： Disclosed herein is spindle ferromagnetic alloy particles having the aspect ratio (major:minor) of less than 3:1 and the coercive force of 500 to 100 Oe, and containing 0.1 to 13 atomic % of Si to Fe, and a process for producing the same.

摘要翻译： 本文公开了具有小于3:1的纵横比（主要：次要）小于3:1的矫顽力和500至100Oe的矫顽力并且含有0.1至13原子％的Si与Fe的锭心铁磁合金颗粒，以及用于制备 相同。

公开(公告)号：US4136158A

公开(公告)日：1979-01-23

申请号：US847446

申请日：1977-11-01

申请人： Yosiro Okuda ,  Nanao Horiishi ,  Hiroshi Sumita ,  Tosiharu Harada

发明人： Yosiro Okuda ,  Nanao Horiishi ,  Hiroshi Sumita ,  Tosiharu Harada

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

CPC分类号： G11B5/70663 ,  C01G49/06 ,  C01P2004/54 ,  C01P2004/62 ,  C01P2006/42

摘要： In the production of acicular ferromagnetic iron oxide of highly uniform particle size by oxidizing an iron (II) hydroxide suspension at a pH of at least 11 with an oxygen-containing gas to form acicular iron (III) oxide hydroxide, reducing and optionally further reoxidizing this into ferromagnetic iron oxide, the improvement which comprises providing the iron (II) hydroxide suspension with a water-soluble silicate in an amount of less than 1.7% by atom based on the amount of the iron (II) hydroxide in the suspension and calculated as the ratio of Si to Fe (II) while prior to the oxidation of the suspension with the oxygen-containing gas.

公开(公告)号：US4873010A

公开(公告)日：1989-10-10

申请号：US039775

申请日：1987-04-15

申请人： Atsushi Takedoi ,  Hiroyuki Kondo ,  Masaru Isoai ,  Yoshitaka Yoshinaga ,  Tosiharu Harada ,  Yosiro Okuda ,  Hiroshi Sumita ,  Hirofumi Kawasaki ,  Kohji Mori

发明人： Atsushi Takedoi ,  Hiroyuki Kondo ,  Masaru Isoai ,  Yoshitaka Yoshinaga ,  Tosiharu Harada ,  Yosiro Okuda ,  Hiroshi Sumita ,  Hirofumi Kawasaki ,  Kohji Mori

IPC分类号： G11B5/706

CPC分类号： G11B5/70689 ,  G11B5/70652

摘要： Disclosed herein are magnetic iron oxide particles comprising spindle-like magnetite or maghemite particles having an aspect ratio(major:minor) of less than 4:1 and containing 0.1 to 20 atomic % of Si to Fe, and a process for producing the same.

摘要翻译： 本文公开了包含具有小于4:1的纵横比（主要：次要）且包含0.1至20原子％的Si与Fe的纺锤状磁铁矿或磁赤铁矿颗粒的磁性氧化铁颗粒及其制备方法。