公开(公告)号：US4165232A

公开(公告)日：1979-08-21

申请号：US942656

申请日：1978-09-15

申请人： Christof Jaeckh ,  Werner Steck ,  Rudolf Brodt ,  Manfred Ohlinger ,  Werner Loeser ,  Eberhard Koester

发明人： Christof Jaeckh ,  Werner Steck ,  Rudolf Brodt ,  Manfred Ohlinger ,  Werner Loeser ,  Eberhard Koester

IPC分类号： H01F1/06 ,  C22C1/04

CPC分类号： H01F1/065 ,  H01F1/061 ,  Y10S428/90

摘要： A process for the manufacture of acicular ferromagnetic metal particles which essentially consist of iron and carry, on their surface, from 0.02 to 0.6% by weight of boron in the form of a borate, by reducing an acicular iron oxide with a gaseous reducing agent at from 250.degree. to 500.degree. C., wherein a compound selected from the group comprising boron oxyacids and their inorganic salts is precipitated on the said iron oxide before reduction.

摘要翻译： 制造针状铁磁性金属颗粒的方法，其主要由铁组成，并在其表面上携带0.02至0.6重量％硼酸盐形式的硼，通过用气态还原剂还原针状氧化铁 从250℃至500℃，其中在还原之前将选自含硼酸及其无机盐的化合物沉淀在所述氧化铁上。

公开(公告)号：US4213959A

公开(公告)日：1980-07-22

申请号：US930513

申请日：1978-08-03

申请人： Rudolf Brodt ,  Helmut Jakusch ,  Eberhard Koester ,  Werner Loeser ,  Manfred Ohlinger ,  Wilhelm Sarnecki ,  Werner Steck

发明人： Rudolf Brodt ,  Helmut Jakusch ,  Eberhard Koester ,  Werner Loeser ,  Manfred Ohlinger ,  Wilhelm Sarnecki ,  Werner Steck

IPC分类号： C01G49/08 ,  C01G49/06 ,  G11B5/62 ,  G11B5/706 ,  H01F1/11

CPC分类号： G11B5/70663 ,  C01G49/06 ,  G11B5/62 ,  G11B5/70647 ,  G11B5/70652 ,  C01P2004/10 ,  C01P2004/54 ,  C01P2004/61 ,  C01P2004/62 ,  C01P2006/42

摘要： A process for the manufacture of acicular ferrimagnetic iron oxide by dehydrating acicular iron(III) oxide hydroxides to give acicular iron(III) oxides, then reducing these iron(III) oxides at from 300.degree. to 650.degree. C. by means of an organic compound which decomposes in this temperature range, and oxidizing the reduced product with an oxygen-containing gas at from 200.degree. to 500.degree. C., wherein the acicular iron(III) oxide hydroxides employed consist of a mixture of goethite and lepidocrocite, containing at least 60% of the latter, and the dehydration is carried out at from 250.degree. to 700.degree. C.

摘要翻译： 通过将针状铁（III）氧化物氢氧化物脱水制成针状亚铁磁性氧化铁，得到针状氧化铁（III），然后通过有机物在300℃至650℃还原这些氧化铁（III） 化合物，其在该温度范围内分解，并在200℃至500℃下用含氧气体氧化还原产物，其中所用的针状（III）氧化物氢氧化物由针铁矿和氯铁矿混合物组成， 最少为60％，脱水为250〜700℃。

公开(公告)号：US4178171A

公开(公告)日：1979-12-11

申请号：US888508

申请日：1978-03-20

申请人： Werner Steck ,  Rudolf Brodt ,  Wilhelm Sarnecki ,  Helmut Jakusch ,  Manfred Ohlinger ,  Eberhard Koester

发明人： Werner Steck ,  Rudolf Brodt ,  Wilhelm Sarnecki ,  Helmut Jakusch ,  Manfred Ohlinger ,  Eberhard Koester

IPC分类号： G11B5/706 ,  B22F9/22 ,  C09D5/23 ,  C09D7/12 ,  C21B15/00 ,  G11B5/712 ,  G11B5/714 ,  H01F1/06 ,  B22F9/00

CPC分类号： H01F1/065 ,  B22F9/22 ,  C21B15/00 ,  G11B5/714

摘要： A process for the manufacture of acicular ferromagnetic iron particles by reducing acicular iron(III) oxide hydroxides which consist of pure synthetic lepidocrocite or a mixture of synthetic goethite and at least 70% by weight of synthetic lepidocrocite.The iron(III) oxide hydroxides used carry, on their surface, an alkaline earth metal cation and an anion of a monobasic, dibasic or tribasic aliphatic carboxylic acid of up to 6 carbon atoms or an organic compound containing at least two groups capable of chelating the alkaline earth metal cation, and are produced in such a way that they consist of at least 70 percent by weight of lepidocrocite and have a length-to-width ratio of not less than 15:1.Reduction of such iron(III) oxide hydroxides gives iron particles with pronounced shape anisotropy, which exhibit both good magnetic properties and a narrow field strength distribution.

摘要翻译： 通过还原针状铁（III）氢氧化物来制造针状铁磁性铁粒子的方法，该针状铁氧化物由纯合成锂铁矿石或合成针铁矿和至少70％重量的合成锂铁矿石混合物组成。 所用的氧化铁（III）氢氧化物在其表面上带有至多6个碳原子的一元，二元或三元脂肪族羧酸的碱土金属阳离子和阴离子，或含至少两个能够螯合的基团的有机化合物 碱土金属阳离子，并且以这样的方式制备，使得它们由至少70重量％的氯铁矿石组成，并且具有不小于15:1的长宽比。 这种氧化还原铁（III）氢氧化物的还原产生具有显着形状各向异性的铁颗粒，其具有良好的磁性能和窄的场强分布。