公开(公告)号：EP0135774A3

公开(公告)日：1987-04-08

申请号：EP84109720

申请日：1984-08-16

Applicant: Hitachi Maxell Ltd. ,  SAKAI CHEMICAL INDUSTRY CO., LTD.,

Inventor： Andoh, Haruo ,  Matsumoto, Seiji

IPC: G11B05/714 ,  G11B05/704 ,  G11B05/712

CPC classification number: G11B5/714 ,  G11B5/70652 ,  G11B5/712 ,  Y10S428/90 ,  Y10T428/256

Abstract: A magnetic recording medium comprising a nonmagnetic support and a magnetic layer provided thereon, said magnetic layer comprising a magnetic recording element and a binder, characterized in that said magnetic recording element mainly comprises acicular gamme-Fe 2 O 3 , particles having a porosity of not more than 5% by volume in average, a specific surface area of 24 to 30 m'/g and the intensity at the face (210) to that at the face (311) in the X ray diffraction being not more than 5%, said magnetic recording medium being much improved in electromagnetic conversion characteristics such as sensitivity and noise.

公开(公告)号：WO1991001548A1

公开(公告)日：1991-02-07

申请号：PCT/JP1990000908

申请日：1990-07-13

Applicant: TDK CORPORATION ,  TAMAI, Kiminori ,  KUROSE, Shigeo ,  OKUYAMA, Kiyotaka

Inventor： TDK CORPORATION

IPC: G11B05/712

CPC classification number: G11B5/714 ,  G11B5/70615 ,  G11B5/712 ,  Y10S428/90 ,  Y10T428/2991

Abstract: A magnetic recording medium having a magnetic layer formed from a mixture of a magnetic metal powder mainly comprising iron with a binder, wherein said metal powder is one prepared by depositing on the surface of iron oxide powder which may be hydrous either zirconium, aluminum and silicon compounds or zirconium, aluminum and silicon compounds or zirconium, aluminum and cobalt compounds, followed by reducing in a reductive atmosphere. This medium has an excellent surface smoothness, a small coefficient of friction, and an excellent durability in travelling.

公开(公告)号：WO1995001637A1

公开(公告)日：1995-01-12

申请号：PCT/JP1994001030

申请日：1994-06-27

Applicant: TDK CORPORATION

Inventor： TDK CORPORATION ,  HANDA, Takashi ,  TAMAI, Kiminori

IPC: G11B05/712

CPC classification number: G11B5/7013 ,  G11B5/712 ,  Y10S428/90 ,  Y10T428/256 ,  Y10T428/2982 ,  Y10T428/2991

Abstract: A magnetic recording medium comprising a non-magnetic support and, formed thereon, a magnetic layer containing a binder and a magnetic powder having the surface mainly comprising carbon and/or iron carbide. The magnetic layer contains an organic dye compound having at least one polar group selected from hydroxyl, carboxyl, sulfo and salts thereof, and the binder contains an amino group and/or an ammonium salt group. This medium is improved in the dispersion of a magnetic coating and also in surface properties, magnetic characteristics, and electromagnetic transduction performance.

Abstract translation: 一种磁记录介质，包括非磁性载体，并在其上形成含有粘合剂的磁性层和具有主要包含碳和/或碳化铁的表面的磁性粉末。 磁性层含有具有至少一个选自羟基，羧基，磺基及其盐的极性基团的有机染料化合物，并且粘合剂含有氨基和/或铵盐基团。 该介质在磁性涂层的分散性以及表面性能，磁特性和电磁传导性能方面得到改善。

公开(公告)号：WO1995002242A1

公开(公告)日：1995-01-19

申请号：PCT/US1994005537

申请日：1994-05-17

Applicant: MINNESOTA MINING AND MANUFACTURING COMPANY

Inventor： MINNESOTA MINING AND MANUFACTURING COMPANY ,  BLAGEV, Albena, V.

IPC: G11B05/712

CPC classification number: G11B5/70673

Abstract: A doped magnetic iron oxide particle suitable for use in magnetic recording media, and methods of preparing the doped magnetic iron oxide particle, are disclosed. The doped magnetic iron oxide particle has the general formula: CoxFe 1-xFe2 O4, wherein O

Abstract translation: 公开了适用于磁记录介质的掺杂的磁性氧化铁颗粒以及制备掺杂的磁性氧化铁颗粒的方法。 掺杂的磁性氧化铁颗粒具有以下通式：Co x Fe 2+ 1-x Fe 2 O 3，其中O

公开(公告)号：EP0214644A3

公开(公告)日：1988-10-05

申请号：EP86112409

申请日：1986-09-08

Applicant: Olin Corporation

Inventor： Crane, Jacob ,  Muench, George J. ,  Saleh, Yousef ,  Lin, Lifun

IPC: B22F09/16 ,  H01F01/06 ,  G11B05/712 ,  C22C01/04

CPC classification number: C22C1/04 ,  B22F1/004 ,  B22F9/16 ,  B22F2998/10 ,  G11B5/70605 ,  G11B5/712 ,  C21D8/00 ,  C25F1/00

Abstract: The present invention relates to a method for producing magnetic particles for use in recording media. The method comprises providing an alloy capable of forming a magnetic precipitate, aging the alloy to form a magnetic precipitate comprising a plurality of magnetic particles dispersed throughout a surrounding matrix; and dissolving the matrix to leave the magnetic particles. Magnetic particles produced by the present method are characterized by a size in the range of about 100A to about 2000A, a single magnetic domain, an aspect ratio up to about 10:1, a relatively smooth surface, and a substantially uniform composition throughout.

公开(公告)号：EP0165076A3

公开(公告)日：1987-10-07

申请号：EP85304321

申请日：1985-06-17

Applicant: Hitachi Maxell Ltd.

Inventor： Kuse, Sadamu ,  Kawarai, Seigi

IPC: G11B05/708 ,  G11B05/712

CPC classification number: G11B5/708 ,  Y10S428/90 ,  Y10T428/25 ,  Y10T428/2982 ,  Y10T428/2991 ,  Y10T428/30

Abstract: A magnetic recording medium having an excellent electromagnetic property with a low frictional magnetic layer surface which comprises a base material and a magnetic layer provided thereon, said magnetic layer comprising magnetic powder, a resinous binder and graphitized carbon black powder, optionally with non-graphitized carbon black powder.

Abstract translation: 一种磁记录介质，其具有优良的电磁特性和低摩擦磁性层表面，所述低摩擦磁性层表面包括基材和设置在其上的磁性层，所述磁性层包含磁性粉末，树脂粘合剂和石墨化炭黑粉末，任选地具有非石墨化碳 黑火药。

公开(公告)号：WO1998022942A1

公开(公告)日：1998-05-28

申请号：PCT/GB1997003152

申请日：1997-11-17

Applicant: MAYES, Eric, Leigh ,  TYLER, Malvin, Nicolas

IPC: G11B05/712

CPC classification number: B82Y25/00 ,  C07K14/47 ,  G11B5/712 ,  G11B5/714 ,  G11B5/855 ,  H01F1/0054 ,  H01F1/0063 ,  Y10T428/25 ,  Y10T428/256 ,  Y10T428/26 ,  Y10T428/2991

Abstract: Theres is disclosed a magnetic recording medium which includes a magnetizable layer thereon, wherein said magnetizable layer comprises a plurality of ferri- or ferromagnetic particles each having a largest dimension no greater than 100nm, and each of which particles represents a separate ferromagnetic domain.

Abstract translation: Theres公开了一种在其上包括可磁化层的磁记录介质，其中所述可磁化层包括多个铁或铁磁颗粒，每个具有不大于100nm的最大尺寸，并且其中每个颗粒表示单独的铁磁畴。

公开(公告)号：WO1998019300A1

公开(公告)日：1998-05-07

申请号：PCT/US1997016004

申请日：1997-09-10

Applicant: AMPEX CORPORATION

Inventor： AMPEX CORPORATION ,  DAVIES, David, H. ,  COUGHLIN, Thomas, M. ,  GOOCH, Beverley, R.

IPC: G11B05/712

CPC classification number: G11B5/712 ,  G11B5/716 ,  Y10S428/90 ,  Y10T428/12465 ,  Y10T428/24942 ,  Y10T428/2495 ,  Y10T428/265 ,  Y10T428/2991

Abstract: The flexible, particulate magnetic storage medium includes a substrate and a magnetic storage layer of hard magnetic particles held within a binder. The flexible, particulate magnetic storage medium also includes a soft magnetic keeper layer. The soft magnetic keeper layer may be established by coating the individual hard magnetic particles of the magnetic storage layer with a layer of soft magnetic material to establish a "keeper layer" around each particle. A break layer of non-magnetic material may be provided between the hard and soft layers. The individual particles are coated by methods such as in situ precipitation. The soft magnetic layer may also be established by providing a separate layer of soft magnetic material within a binder of cross-linkable resins. The resulting flexible, particulate magnetic storage medium is a laminate principally comprising a substrate, a first layer of hard magnetic particles within a binder, and a second layer of soft magnetic particles also within a binder. The laminate medium may be produced through extrusion of binder particle mixes through multi aperture slot die extensions. The flexible, particulate magnetic media may be used in tape or flexible disc formats.

Abstract translation: 柔性颗粒磁性存储介质包括基材和保持在粘合剂内的硬磁性颗粒的磁存储层。 柔性颗粒磁存储介质还包括软磁保持层。 可以通过用磁性材料层涂覆磁存储层的各个硬磁性颗粒以在每个颗粒周围建立“保持层”来建立软磁性层。 可以在硬层和软层之间提供非磁性材料的断裂层。 通过诸如原位沉淀的方法涂覆各个颗粒。 也可以通过在可交联树脂的粘合剂内提供单独的软磁性材料层来建立软磁性层。 所得到的柔性颗粒状磁性存储介质是主要包括基底，粘合剂内的第一层硬磁性颗粒和粘合剂内的软磁性颗粒的第二层的层压体。 层压介质可以通过粘合剂颗粒混合物通过多孔隙槽模延伸而挤出来生产。 灵活的微粒磁性介质可以以磁带或软盘形式使用。

公开(公告)号：WO1992008227A1

公开(公告)日：1992-05-14

申请号：PCT/US1991008051

申请日：1991-11-05

Applicant: EASTMAN KODAK COMPANY

Inventor： EASTMAN KODAK COMPANY ,  JAMES, Robert, O. ,  BERTUCCI, Sidney, Joseph ,  OLTEAN, George, Leslie

IPC: G11B05/712

CPC classification number: G11B5/70657 ,  G11B5/712 ,  Y10T428/257 ,  Y10T428/2991 ,  Y10T428/2993 ,  Y10T428/2998 ,  Y10T428/31507 ,  Y10T428/3154 ,  Y10T428/31544 ,  Y10T428/31591 ,  Y10T428/31598 ,  Y10T428/31609 ,  Y10T428/31786 ,  Y10T428/31797 ,  Y10T428/31891 ,  Y10T428/31971

Abstract: Magnetic particles are cobalt surface treated gamma iron oxide (Fe2O3) having a specific area of at least 30 m2/g and a powder coercivity greater than about 450 Oe, the particles being coated with from about 10 to about 50 % by weight of a material having a refractive index less than about the refractive index of a binder for the particles.

公开(公告)号：WO1989012887A1

公开(公告)日：1989-12-28

申请号：PCT/EP1989000684

申请日：1989-06-17

Applicant: KODAK-PATHE ,  EASTMAN KODAK COMPANY ,  LE DU, Gilles ,  MARI, Pierre-André, Marie, Vincent

Inventor： KODAK-PATHE ,  EASTMAN KODAK COMPANY

IPC: G11B05/712

CPC classification number: B22F1/02 ,  G11B5/712 ,  H01F1/061

Abstract: This invention concerns a process of treating particles which are unstable in air and the particles obtained which exhibit good corrosion resistance. The method consists in treating the metal particles by a current of gas containing silane and hydrogen in a fluidised bed. The particles may subsequently be subjected to a current of oxygen, preferably in the same fluidised bed, to obtain a coating of silica around the particles. The method is especially useful in obtaining particles of iron for magnetic recording materials which are suitable for dispersion and are corrosion-resistant.