公开(公告)号：US5552072A

公开(公告)日：1996-09-03

申请号：US318877

申请日：1994-10-18

申请人： Takuya Arase ,  Fumihiro Kamiya ,  Masayuki Tsuji ,  Tadashi Ino ,  Ikuo Kitamura ,  Yoshiyuki Shibuya ,  Shigeo Daimon

发明人： Takuya Arase ,  Fumihiro Kamiya ,  Masayuki Tsuji ,  Tadashi Ino ,  Ikuo Kitamura ,  Yoshiyuki Shibuya ,  Shigeo Daimon

IPC分类号： B22F1/00 ,  C01B31/30 ,  G11B5/706 ,  C04B35/00

CPC分类号： B22F1/004 ,  C01B31/301 ,  G11B5/706 ,  G11B5/70605 ,  G11B5/70615 ,  C01P2004/10 ,  C01P2004/54 ,  C01P2004/62 ,  C01P2004/80 ,  C01P2006/42 ,  C01P2006/80 ,  Y10T428/2991

摘要： An acicular fine particulate material which is coated with a compound containing at least one element selected from among elements of Groups III and IV of the Periodic Table in Periods 5 and 6, the acicular fine particulate material being one of (i) an acicular fine particulate material containing iron carbide, (ii) an acicular fine particulate material containing iron carbide, metallic iron and carbon, and (iii) an acicular fine particulate metallic iron containing carbon, is prepared by a promoted reduction reaction while being effectively prevented from sintering and consequently affords magnetic recording media having a high recording density.

摘要翻译： PCT No.PCT / JP94 / 00242 Sec。 371日期：1994年10月18日 102（e）日期1994年10月18日PCT 1994年2月17日PCT PCT。 公开号WO94 / 19276 日期1994年9月1日针对在第5和6周期中涂覆有选自元素周期表第III和IV族元素中的至少一种元素的化合物的针状细颗粒材料，针状细颗粒材料是（i ）含有碳化铁的针状细颗粒材料，（ii）含有碳化铁，金属铁和碳的针状细颗粒材料和（iii）通过促进还原反应而有效地制备含有碳的针状细颗粒金属铁 防止烧结，从而提供具有高记录密度的磁记录介质。

公开(公告)号：US5660927A

公开(公告)日：1997-08-26

申请号：US281657

申请日：1994-07-28

申请人： Takuya Arase ,  Yoshiyuki Shibuya ,  Ikuo Kitamura ,  Shigeo Daimon

发明人： Takuya Arase ,  Yoshiyuki Shibuya ,  Ikuo Kitamura ,  Shigeo Daimon

IPC分类号： G11B5/706 ,  G11B5/714 ,  G11B5/66

CPC分类号： G11B5/70626 ,  G11B5/70615 ,  G11B5/714 ,  Y10S428/90 ,  Y10T428/256 ,  Y10T428/257

摘要： The present invention provides acicular fine particles made up of iron and carbon, and these acicular metal iron fine particles can be prepared by contacting acicular iron carbide fine particles with a reducing agent containing no carbon atom. Further, the present invention provides a magnetic coating composition and magnetic recording medium containing the above acicular metal iron fine particles.

摘要翻译： 本发明提供由铁和碳构成的针状细颗粒，并且可以通过使针状碳化铁微粒与不含碳原子的还原剂接触来制备这些针状金属铁微粒。 此外，本发明提供一种磁性涂料组合物和含有上述针状金属铁微粒的磁记录介质。

公开(公告)号：US5443666A

公开(公告)日：1995-08-22

申请号：US117169

申请日：1993-09-17

申请人： Ikuo Kiatamura ,  Takuya Arase ,  Fumihiro Kamiya ,  Shigeo Daimon

发明人： Ikuo Kiatamura ,  Takuya Arase ,  Fumihiro Kamiya ,  Shigeo Daimon

IPC分类号： B22F1/00 ,  C01B31/30 ,  C22C33/02 ,  G11B5/706 ,  G11B5/714 ,  H01F1/06 ,  H01F1/09 ,  H01F1/03

CPC分类号： C22C33/0292 ,  B22F1/004 ,  C01B31/301 ,  G11B5/70615 ,  G11B5/70626 ,  G11B5/714 ,  H01F1/065 ,  H01F1/09 ,  C01P2002/72 ,  C01P2004/10 ,  C01P2004/52 ,  C01P2004/62 ,  C01P2004/80 ,  C01P2006/12 ,  C01P2006/80

摘要： The present invention provides an acicular fine particles obtained by reducing an iron carbide starting material and containing metal iron, iron carbide and free carbon, the acicular fine particles having a mean particle size (long axis) of 0.1 to 0.5 .mu.m and an average axial ratio of 3 to 15 and containing 15 to 80 wt. % of metal iron, 10 to 75 wt. % of iron carbide and 5 to 13 wt. % of free carbon, process thereof, magnetic coating composition and magnetic recording medium containing the same.

摘要翻译： PCT No.PCT / JP93 / 00060 Sec。 371日期：1993年9月17日 102（e）1993年9月17日PCT 1993年11月20日PCT公布。 公开号WO93 / 14896 日期：1993年5月8日本发明提供一种通过还原铁素体原料并含有金属铁，碳化铁和游离碳而得到的针状细粒，针状细粒的平均粒径（长轴）为0.1〜0.5 平均轴比为3〜15，含有15〜80重量％ ％的金属铁，10〜75wt。 ％的碳化铁和5〜13wt。 游离碳的％，其工艺，磁性涂料组合物和含有它们的磁记录介质。

公开(公告)号：US4900464A

公开(公告)日：1990-02-13

申请号：US944163

申请日：1986-12-22

申请人： Takuya Arase ,  Yoshiyuki Shibuya ,  Shigeo Daimon

发明人： Takuya Arase ,  Yoshiyuki Shibuya ,  Shigeo Daimon

IPC分类号： B01J27/22 ,  C01B31/30 ,  G11B5/706

CPC分类号： B01J27/22 ,  C01B31/301 ,  G11B5/70615 ,  G11B5/70626 ,  G11B5/70642 ,  C01P2002/72 ,  C01P2002/77 ,  C01P2004/10 ,  C01P2004/54 ,  C01P2004/61 ,  C01P2004/62 ,  C01P2006/42 ,  C01P2006/80

摘要： The present invention provides acicular particles (A) containing an iron carbide, which have (a) a free carbon content of at most 20 wt. %, and (b) an Fe.sub.5 C.sub.2 ratio(x) of at least 70% and a coercive force of 3x+300 to 7x+270 Oe, the ratio(x) being expressed by ##EQU1## wherein S1 is the X-ray diffraction strength of Fe.sub.5 C.sub.2, and S2 is the X-ray diffraction strength of Fe.sub.3 O.sub.4. The invention further provides particles (B) containing nickel and an iron carbide. The invention further provides acicular particles containing an iron carbide which are obtained by heating an aqueous dispersion of ferric hydroxide in an alkaline system in the presence of a water-soluble compound capable of coordinating to iron to obtain acicular .alpha.-ferric oxide and contacting the product with a carbon-containing reducing-and-carburizing agent or with a mixture of the agent and a carbon-free reducing agent, with or without contacting the product with the carbon-free reducing agent. These particles (A) to (C) are controllable in coercive force and usable for magnetic record media of various standards.

公开(公告)号：US5437805A

公开(公告)日：1995-08-01

申请号：US134873

申请日：1993-10-12

申请人： Takuya Arase ,  Yoshiyuki Shibuya ,  Shigeo Daimon

发明人： Takuya Arase ,  Yoshiyuki Shibuya ,  Shigeo Daimon

IPC分类号： B01J27/22 ,  C01B31/30 ,  G11B5/706

CPC分类号： B01J27/22 ,  C01B31/301 ,  G11B5/70615 ,  G11B5/70626 ,  G11B5/70642 ,  C01P2002/72 ,  C01P2002/77 ,  C01P2004/10 ,  C01P2004/54 ,  C01P2004/61 ,  C01P2004/62 ,  C01P2006/42 ,  C01P2006/80

摘要： The present invention provides acicular particles (A) containing an iron carbide, which have (a) a free carbon content of at most 20 wt. %, and (b) and Fe.sub.5 C.sub.2 ratio(x) of at least 70% and a coercive force of 3.times.+300 to 7.times.+270 Oe, the ratio(x) being expressed by ##EQU1## where S1 is the X-ray diffraction strength of Fe.sub.5 C.sub.2, and S2 is the X-ray diffraction strength of Fe.sub.3 O.sub.4.The invention further provides particles (B) containing nickel and an iron carbide.The invention further provides acicular particles containing an iron carbide which are obtained by heating an aqueous dispersion of ferric hydroxide in an alkaline system in the presence of a water-soluble compound capable of coordinating to iron to obtain acicular .alpha.-ferric oxide and contacting the product with a carbon-containing reducing-and-carburizing agent or with a mixture of the agent and a carbon-free reducing agent, with or without contacting the product with the carbon-free reducing agent.These particles (A) and (C) are controllable in coercive force and usable for magnetic record media of various standards.

摘要翻译： 本发明提供了含有碳化铁的针状粒子（A），其具有（a）游离碳含量至多为20重量％ ％，（b）和Fe5C2比（x）至少为70％，矫顽力为3x + 300〜7×270ee，比例（x）由表示，其中S1为X射线衍射 Fe5C2的强度，S2是Fe3O4的X射线衍射强度。 本发明还提供含有镍和碳化铁的颗粒（B）。 本发明还提供了含有碳化铁的针状颗粒，其通过在碱性体系中在能够与铁配位的水溶性化合物的存在下加热氢氧化铁的水分散体而获得，得到针状的α-氧化铁并与产物接触 与含碳还原和渗碳剂或与该试剂和不含碳的还原剂的混合物，与或不使该产物与无碳还原剂接触。 这些颗粒（A）和（C）在矫顽力方面是可控的，可用于各种标准的磁记录介质。

公开(公告)号：US5104561A

公开(公告)日：1992-04-14

申请号：US617294

申请日：1990-11-19

申请人： Ikuo Kitamura ,  Yoshiyuki Shibuya ,  Takashi Shibanuma ,  Shigeo Daimon

发明人： Ikuo Kitamura ,  Yoshiyuki Shibuya ,  Takashi Shibanuma ,  Shigeo Daimon

IPC分类号： C01B31/30 ,  H01F1/11

CPC分类号： H01F1/11 ,  C01B31/301 ,  C01P2002/72 ,  C01P2002/88 ,  C01P2006/42 ,  C01P2006/80

摘要： Fine iron carbide particles consisting essentially of iron carbide, which are characterized in that, in the step of the variation of the weight under the condition of combustion, the increase of the weight in the equilibrium after arrival at the maximum weight is 22% or less, on the basis of the weight before combustion.

公开(公告)号：US4931198A

公开(公告)日：1990-06-05

申请号：US408955

申请日：1989-09-18

申请人： Takuya Arase ,  Katsushi Tokunaga ,  Shigeo Daimon

发明人： Takuya Arase ,  Katsushi Tokunaga ,  Shigeo Daimon

IPC分类号： H01F1/11 ,  B01J23/22 ,  C01B31/30 ,  G11B5/706

CPC分类号： G11B5/70626 ,  B01J23/22 ,  C01B31/303 ,  C01P2002/72 ,  C01P2002/74 ,  C01P2004/54 ,  C01P2004/61 ,  C01P2004/62 ,  C01P2006/42

摘要： Particles containing FeC are prepared by mixing (a) a boron compound or alkaline earth metal compound with (b) iron oxyhydroxide or iron oxide particles, or coating the former compound (a) to the latter particles (b), and then carburizing the mixture or coated particles with a carburizing agent.

公开(公告)号：US5271857A

公开(公告)日：1993-12-21

申请号：US828625

申请日：1992-01-31

申请人： Tadashi Ino ,  Nobuhiro Shinka ,  Shigeo Daimon

发明人： Tadashi Ino ,  Nobuhiro Shinka ,  Shigeo Daimon

IPC分类号： C09D5/23 ,  C09D7/80 ,  G11B5/706 ,  G11B5/84 ,  H01F10/14 ,  H01F10/18

CPC分类号： G11B5/84 ,  G11B5/70615 ,  G11B5/70626

摘要： The present invention provides a process for preparing a magnetic coating composition with use of magnetic particles containing carbon or magnetic particles consisting primarily of an iron carbide, the process being characterized in that the process includes the step of pre-kneading the magnetic particles with an organic solvent.

公开(公告)号：US5205950A

公开(公告)日：1993-04-27

申请号：US723887

申请日：1991-07-01

申请人： Yoshiyuki Shibuya ,  Naoki Miyamoto ,  Shigeo Daimon

发明人： Yoshiyuki Shibuya ,  Naoki Miyamoto ,  Shigeo Daimon

IPC分类号： C01B31/30 ,  G11B5/706 ,  H01F1/11

CPC分类号： G11B5/70615 ,  C01B31/303 ,  C01P2002/72 ,  C01P2004/54 ,  C01P2004/61 ,  C01P2004/62

摘要： The present invention provides a process for preparing iron carbide fine particles having an average particle size (long axis) of 0.1 to 2 .mu.m and an average axial ratio of 3 to 20, which comprises,(a) optionally contacting an iron compound selected from the group consisting of iron oxyhydroxide fine particles and iron oxide fine particles with a reducing agent which does not contain carbon atom, the iron compound being, prior to the above contact, coated with iron compound or iron compound and cobalt compound, and with aluminum compound or silicon compound, and(b) contacting the iron compound of the above (a) with a reducing-and-carburizing agent containing carbon atom or a mixture thereof with a reducing agent which does not contain carbon atom.

公开(公告)号：US5346758A

公开(公告)日：1994-09-13

申请号：US935083

申请日：1986-11-24

申请人： Yoshiyuki Shibuya ,  Shigeo Daimon ,  Kazuo Okamura

发明人： Yoshiyuki Shibuya ,  Shigeo Daimon ,  Kazuo Okamura

IPC分类号： C09D5/23 ,  C08K3/10 ,  G11B5/706 ,  G11B5/00

CPC分类号： G11B5/70668 ,  Y10S428/90 ,  Y10T428/25 ,  Y10T428/256 ,  Y10T428/257 ,  Y10T428/2991 ,  Y10T428/30

摘要： A magnetic coating composition comprising acicular particles containing iron carbide and a main magnetic material.

摘要翻译： 一种磁性涂料组合物，其包含含有碳化铁的针状颗粒和主要磁性材料。