公开(公告)号：US09311946B2

公开(公告)日：2016-04-12

申请号：US13211051

申请日：2011-08-16

Applicant: Kenji Tanaka ,  Masao Fujita ,  Sadamu Kuse

Inventor： Kenji Tanaka ,  Masao Fujita ,  Sadamu Kuse

IPC: G11B5/71 ,  G11B5/714 ,  G11B5/738

CPC classification number: G11B5/71 ,  G11B5/70615 ,  G11B5/70626 ,  G11B5/714 ,  G11B5/738 ,  G11B5/78

Abstract: A magnetic recording medium of the present invention is a magnetic recording medium including a non-magnetic substrate; a non-magnetic layer that is formed on one of principal surfaces of the non-magnetic substrate and contains a non-magnetic powder, a binder, and a lubricant; and a magnetic layer that is formed on a principal surface of the non-magnetic layer opposite to the non-magnetic substrate and contains a magnetic powder and a binder. The magnetic powder has an average particle size between 10 nm and 35 nm inclusive. The lubricant is migratable to the magnetic layer and forms a lubricant layer on a surface of the magnetic layer when a pressure is applied to the magnetic layer. When spacing of the surface of the magnetic layer before and after washing the lubricant with n-hexane is measured with a TSA (Tape Spacing Analyzer), the value of the spacing after washing is 3 to 10 nm, and the value of the spacing before washing is 1 to 5 nm smaller than the value of the spacing after washing.

Abstract translation: 本发明的磁记录介质是包括非磁性基片的磁记录介质; 非磁性层，其形成在所述非磁性基板的一个主表面上并且包含非磁性粉末，粘合剂和润滑剂; 以及形成在与非磁性基板相对的非磁性层的主表面上并且包含磁性粉末和粘合剂的磁性层。 磁性粉末的平均粒径为10nm〜35nm。 当向磁性层施加压力时，润滑剂可移动到磁性层并在磁性层的表面上形成润滑剂层。 当使用TSA（胶带间隔分析仪）测量用正己烷洗涤润滑剂之前和之后的磁性层表面的间隔时，洗涤后的间隔值为3至10nm，并且之前的间隔值 洗涤比洗涤后的间隔值小1〜5nm。

公开(公告)号：US08535634B2

公开(公告)日：2013-09-17

申请号：US12151239

申请日：2008-05-05

Applicant: Suryanarayan G. Sankar ,  Satoru Simizu ,  Brian J. Zande ,  Richard T. Obermyer

Inventor： Suryanarayan G. Sankar ,  Satoru Simizu ,  Brian J. Zande ,  Richard T. Obermyer

IPC: B32B5/16

CPC classification number: C01B21/0622 ,  C01P2006/42 ,  C22C38/001 ,  G11B5/70626 ,  H01F1/065

Abstract: A method of making iron nitride powder is provided. The method comprises the steps of: a) providing an iron-based starting material; b) reducing the starting material by heating the starting material in a fluidized bed reactor in the presence of a reducing agent; c) nitriding the material obtained from step (b) by contacting the material with a nitrogen source. Also provided is the iron nitride powder made by the above method.

Abstract translation: 提供了制造氮化铁粉末的方法。 该方法包括以下步骤：a）提供铁基原料; b）通过在还原剂的存在下在流化床反应器中加热原料来还原原料; c）通过使材料与氮源接触来氮化从步骤（b）获得的材料。 还提供了通过上述方法制备的氮化铁粉末。

公开(公告)号：US20120045664A1

公开(公告)日：2012-02-23

申请号：US13211051

申请日：2011-08-16

Applicant: Kenji TANAKA ,  Masao Fujita ,  Sadamu Kuse

Inventor： Kenji TANAKA ,  Masao Fujita ,  Sadamu Kuse

IPC: G11B5/70 ,  G11B5/714 ,  G11B5/71

CPC classification number: G11B5/71 ,  G11B5/70615 ,  G11B5/70626 ,  G11B5/714 ,  G11B5/738 ,  G11B5/78

Abstract: A magnetic recording medium of the present invention is a magnetic recording medium including a non-magnetic substrate; a non-magnetic layer that is formed on one of principal surfaces of the non-magnetic substrate and contains a non-magnetic powder, a binder, and a lubricant; and a magnetic layer that is formed on a principal surface of the non-magnetic layer opposite to the non-magnetic substrate and contains a magnetic powder and a binder. The magnetic powder has an average particle size between 10 inn and 35 nm inclusive. The lubricant is migratable to the magnetic layer and forms a lubricant layer on a surface of the magnetic layer when a pressure is applied to the magnetic layer. When spacing of the surface of the magnetic layer before and after washing the lubricant with n-hexane is measured with a TSA (Tape Spacing Analyzer), the value of the spacing after washing is 3 to 10 nm, and the value of the spacing before washing is 1 to 5 nm smaller than the value of the spacing after washing.

Abstract translation: 本发明的磁记录介质是包括非磁性基片的磁记录介质; 非磁性层，其形成在所述非磁性基板的一个主表面上并且包含非磁性粉末，粘合剂和润滑剂; 以及形成在与非磁性基板相对的非磁性层的主表面上并且包含磁性粉末和粘合剂的磁性层。 该磁性粉末的平均粒径为10至35纳米（含）。 当向磁性层施加压力时，润滑剂可移动到磁性层并在磁性层的表面上形成润滑剂层。 当使用TSA（胶带间隔分析仪）测量用正己烷洗涤润滑剂之前和之后的磁性层表面的间隔时，洗涤后的间隔值为3至10nm，并且之前的间隔值 洗涤比洗涤后的间隔值小1〜5nm。

公开(公告)号：US20090252991A1

公开(公告)日：2009-10-08

申请号：US12308112

申请日：2007-06-08

Applicant: Yuzo Ishikawa ,  Kenji Masada

Inventor： Yuzo Ishikawa ,  Kenji Masada

IPC: G11B5/62 ,  C23C8/10

CPC classification number: G11B5/70626 ,  B82Y30/00 ,  C01B21/0622 ,  C01P2004/64 ,  C01P2004/80 ,  C01P2006/42 ,  G11B5/712 ,  G11B5/714 ,  H01F1/065 ,  H01F1/09

Abstract: Provided is an iron nitride-based magnetic powder that comprises magnetic particles having a mean particle size of at most 20 nm. The magnetic particle has a core of a main phase of Fe16N2 and has, on the outer side of the core, an oxide phase derived from a metal Fe phase formed by reduction of iron nitride. In relation to the weatherability index Δσs and the saturation magnetization as thereof, the magnetic powder satisfies Δσs≦0.8×σs−30. In this, Δσs=(σs−σs1)/σs×100. σs1 means the saturation magnetization of the magnetic powder kept in an atmosphere of 60° C. and 90% RH for 1 week. The powder can be obtained by exposing powder particles having a main phase of Fe16N2 to a reducing gas to partly reduce the region of the surface of the particles into a metal Fe phase (gradual reduction) followed by exposing them to an oxidizing gas to oxidize a part of the surface of the metal Fe phase into an oxide phase (gradual oxidation).

Abstract translation: 提供一种含有平均粒径为20nm以下的磁性粒子的氮化铁系磁性粉末。 磁性颗粒具有Fe16N2的主相的芯，并且在芯的外侧具有衍生自通过还原氮化铁形成的金属Fe相的氧化物相。 关于耐候性指数Deltasigmas和饱和磁化强度，磁粉满足Deltasigmas <= 0.8xsigmas-30。 在这里，Deltasigmas =（sigmas-sigmas1）/ sigmasx100。 sigmas1表示磁粉的饱和磁化强度保持在60℃和90％RH的气氛中1周。 可以通过将具有Fe16N2主相的粉末颗粒暴露于还原气体来部分地将颗粒表面的区域还原为金属Fe相（逐渐还原），然后将其暴露于氧化气体以氧化 部分表面的金属Fe相变成氧化相（逐渐氧化）。

公开(公告)号：US20060068232A1

公开(公告)日：2006-03-30

申请号：US10948259

申请日：2004-09-24

Applicant: Hisanobu Mikamo ,  Seigi Kawarai ,  Sadamu Kuse

Inventor： Hisanobu Mikamo ,  Seigi Kawarai ,  Sadamu Kuse

IPC: G11B5/708

CPC classification number: G11B5/70626 ,  G11B5/714 ,  G11B5/716

Abstract: A magnetic tape comprising a non-magnetic substrate and at least one magnetic layer formed on one surface of the non-magnetic substrate, characterized in that magnetic particles contained in an uppermost magnetic layer of the magnetic layer are substantially granular particles with a particle size of 30 nm or less, and that the ratio of a coercive force HcM in the machine direction to a coercive force HcT in the transverse direction, i.e., [HcM/HcT], is at least 2.2. This magnetic tape has a capacity capable of corresponding to mass storage of 1 TB or more, and achieves a high ratio of reproducing output to noises (C/N), particularly for signals within a short wavelength range, thus showing excellent high-density recording performance.

Abstract translation: 一种磁带，其包含非磁性基底和形成在所述非磁性基底的一个表面上的至少一个磁性层，其特征在于，所述磁性层的最上层的磁性层中所含的磁性粒子是粒径为 30nm以下，并且矫顽力Hc在机械方向上的相对于横向的矫顽力Hc T 的比例，即[Hc _{M>至少为2.2。 该磁带具有能够对应于1TB以上的大容量存储容量的能力，并且实现了对于噪声（C / N）的再现输出的高比率，特别是对于短波长范围内的信号，因此显示出优异的高密度记录 性能。}

公开(公告)号：US5443666A

公开(公告)日：1995-08-22

申请号：US117169

申请日：1993-09-17

Applicant: Ikuo Kiatamura ,  Takuya Arase ,  Fumihiro Kamiya ,  Shigeo Daimon

Inventor： Ikuo Kiatamura ,  Takuya Arase ,  Fumihiro Kamiya ,  Shigeo Daimon

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

CPC classification number: 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

Abstract: 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.

Abstract translation: 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：US5437805A

公开(公告)日：1995-08-01

申请号：US134873

申请日：1993-10-12

Applicant: Takuya Arase ,  Yoshiyuki Shibuya ,  Shigeo Daimon

Inventor： Takuya Arase ,  Yoshiyuki Shibuya ,  Shigeo Daimon

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

CPC classification number: 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

Abstract: 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.

Abstract translation: 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：US5271857A

公开(公告)日：1993-12-21

申请号：US828625

申请日：1992-01-31

Applicant: Tadashi Ino ,  Nobuhiro Shinka ,  Shigeo Daimon

Inventor： Tadashi Ino ,  Nobuhiro Shinka ,  Shigeo Daimon

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

CPC classification number: G11B5/84 ,  G11B5/70615 ,  G11B5/70626

Abstract: 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：US4931198A

公开(公告)日：1990-06-05

申请号：US408955

申请日：1989-09-18

Applicant: Takuya Arase ,  Katsushi Tokunaga ,  Shigeo Daimon

Inventor： Takuya Arase ,  Katsushi Tokunaga ,  Shigeo Daimon

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

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

Abstract: 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：US4547393A

公开(公告)日：1985-10-15

申请号：US618803

申请日：1984-06-08

Applicant: Takamitsu Asai ,  Tatsuji Kitamoto ,  Goro Akashi

Inventor： Takamitsu Asai ,  Tatsuji Kitamoto ,  Goro Akashi

IPC: G11B5/706 ,  G11B5/708 ,  G11B5/845 ,  G11B5/84

CPC classification number: G11B5/845 ,  G11B5/70626 ,  G11B5/7085

Abstract: The present invention relates to an improved method for preparing a magnetic recording method having excellent magnetic orientation comprising the steps of (1) dispersing ferromagnetic fine particles which are plate-shaped and which have an axis of magnetization perpendicular to the plates of the particles in a binder and (2) coating a magnetic coating layer on a non-magnetic support wherein the method comprises, after coating the magnetic coating layer and before drying it, subjecting the surface of the magnetic layer to a magnetic field from the direction perpendicular to the support to produce a magnetic orientation while contacting the surface of the magnetic layer with a flexible smoothening sheet.

Abstract translation: 本发明涉及一种制备具有优异磁性取向性的磁记录方法的改进方法，包括以下步骤：（1）将板状的铁磁细颗粒分散在其中，并将磁性轴垂直于颗粒的平板 粘合剂和（2）在非磁性载体上涂覆磁性涂层，其中所述方法包括在涂覆磁性涂层之后并在其干燥之前，使磁性层的表面从垂直于载体的方向受到磁场 以在磁性层的表面与柔性平滑片接触的同时产生磁性取向。