Particles containing iron carbide
    3.
    发明授权
    Particles containing iron carbide 失效
    含有碳化铁的颗粒

    公开(公告)号:US5437805A

    公开(公告)日:1995-08-01

    申请号:US134873

    申请日:1993-10-12

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

    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。

    Particles containing iron carbide
    7.
    发明授权
    Particles containing iron carbide 失效
    含有碳化铁的颗粒

    公开(公告)号:US4900464A

    公开(公告)日:1990-02-13

    申请号:US944163

    申请日:1986-12-22

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

    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.

    Process for producing magnetizable particles
    8.
    发明授权
    Process for producing magnetizable particles 失效
    生产可磁化颗粒的方法

    公开(公告)号:US4457955A

    公开(公告)日:1984-07-03

    申请号:US454325

    申请日:1982-12-29

    摘要: A process for producing cobalt-modified iron oxide particles, which comprises the steps of:(1) adding to magnetic iron oxide particles(a) a cobalt compound,(b) an iron component which is either (b.sub.1) a ferric compound at an atomic ratio to the cobalt compound in the range of 0.68 to 2 or (b.sub.2) a combination of a ferrous compound and a ferric compound, and(c) an alkali at a concentration enough to cause the cobalt and iron to precipitate as hydroxides; and(2) heating the mixture at a temperature of at least 50.degree. C. and not higher than the reflux temperature thereof in a non-oxidizing atmosphere.

    摘要翻译: 一种生产钴改性氧化铁颗粒的方法,包括以下步骤:(1)向磁性氧化铁颗粒(a)中加入钴化合物,(b)铁组分,其中(b1) 与钴化合物的原子比在0.68〜2的范围内,或(b2)亚铁化合物与三价铁化合物的组合,(c)以足以引起钴和铁作为氢氧化物析出的浓度的碱; 和(2)在非氧化性气氛中,在至少50℃,不高于其回流温度的温度下加热混合物。

    Method for Multi-Stage Expansion and Stretching of Film and Filter
    9.
    发明申请
    Method for Multi-Stage Expansion and Stretching of Film and Filter 审中-公开
    膜和过滤器的多级膨胀和拉伸方法

    公开(公告)号:US20140367325A1

    公开(公告)日:2014-12-18

    申请号:US12483341

    申请日:2009-06-12

    IPC分类号: B01D29/07 B29C55/02

    摘要: This invention relates to a multi-stage stretching operation for production of expanded stretched porous polytetrafluoroethylene (ePTFE) fibrous materials with minimal node size and minimized filament sizes. A plurality of stretching or expansions may be implemented on the film including combinations of MDO and TDO stretches including at least two longitudinal stretches and at least one transverse stretch. Subsequent stretches occur at rates generally less than a prior similar longitudinal or transverse type of expansion.

    摘要翻译: 本发明涉及用于生产具有最小节点尺寸和最小化的丝尺寸的膨胀的拉伸多孔聚四氟乙烯(ePTFE)纤维材料的多级拉伸操作。 多个拉伸或膨胀可以在膜上实施,包括MDO和TDO拉伸的组合,其包括至少两个纵向延伸和至少一个横向拉伸。 随后的延伸以通常小于先前类似的纵向或横向类型的膨胀的速率发生。

    Method for preparing filtering material
    10.
    发明授权
    Method for preparing filtering material 有权
    过滤材料的制备方法

    公开(公告)号:US07387700B2

    公开(公告)日:2008-06-17

    申请号:US10473803

    申请日:2002-04-03

    IPC分类号: B32B37/00 B29C65/00

    摘要: A method of manufacturing a filter medium that has a PF value that exceeds 32, the PF value calculated from the pressure loss and the collection efficiency of the filter medium according to the following formula: PF=[−log(permeability (%)/100)/(pressure loss (Pa)]×1000[Formula 1] in which permeability (%)=100−collection efficiency (%). In this method, 380 ml or more of a liquid lubricant at 20° C. is added per 1 kg of a PTFE fine powder, this compound is processed into a tape shape and elongated to obtain a PTFE porous film, and an air permeable support member is heat laminated to at least one surface of the PTFE porous film.

    摘要翻译: 制造PF值超过32的过滤介质的方法,根据压力损失计算的PF值和过滤介质的收集效率根据下式:&lt;&lt; in-line-formula description =“In- PF = [ - log(磁导率(%)/ 100)/(压力损失(Pa)] x1000 [公式1] <?in-line-formula description =“In-line Formulas (%)= 100收集效率(%)的“end =”尾“→>在该方法中,每1kg PTFE细粉末加入20℃下的380ml以上液体润滑剂 ,将该化合物加工成带状并拉长以获得PTFE多孔膜,并且将透气性支撑构件热层压到PTFE多孔膜的至少一个表面上。