公开(公告)号：EP0137949A3

公开(公告)日：1987-08-26

申请号：EP84109547

申请日：1984-08-10

Applicant: KABUSHIKI KAISHA TOSHIBA

Inventor： Ido, Tadashi c/o K.K. Toshiba ,  Kubo, Osamu c/o K.K. Toshiba ,  Fukasawa, Masahiro c/o K.K. Toshiba ,  Maeda, Tatsumi c/o K.K. Toshiba ,  Nomura, Tutomu c/o K.K. Toshiba

IPC: G11B05/714 ,  G11B05/70

CPC classification number: G11B5/714 ,  Y10S428/90 ,  Y10T428/256 ,  Y10T428/257

Abstract: Disclosed is a magnetic recording medium formed of a substrate and a layer of magnetic powder coated on a surface of the substrate, characterized in that the magnetic powder is hexagonal crystals having single domain crystalline magnetic anisotropy, particle sizes of 0.01 to 0.3 µm, particle size/thickness ratios of 2.3 to 15 and the tapping packing rate of said magnetic powder is 15% or more.

Abstract translation: 本发明公开了一种磁性记录介质，其由基底和涂覆在基底表面上的磁性粉末层构成，其特征在于，所述磁性粉末是具有单畴晶体磁各向异性的六方晶体，粒径为0.01-0.3μm，粒径 /厚度比为2.3至15，并且所述磁粉的出料填充率为15％或更高。

公开(公告)号：WO1991014260A1

公开(公告)日：1991-09-19

申请号：PCT/FR1991000194

申请日：1991-03-11

Applicant: SOCIETE ANONYME DES CIMENTS VICAT ,  ESCAFFRE, Pascale ,  DUSSAUD, Joseph ,  MASSART, René ,  CABUIL, Valérie ,  NEVEU, Sophie

Inventor： SOCIETE ANONYME DES CIMENTS VICAT

IPC: G11B05/714

CPC classification number: H01F41/16 ,  G06K19/06187 ,  G11B5/70 ,  G11B5/712 ,  H01F1/44

Abstract: Magnetic composition comprising an emulsion of microdrops of a magnetic liquid consisting of a suspension of magnetic nanoparticles, with said microdrops possibly microencapsulated. Process for manufacturing a magnetic substrate and magnetic substrate obtained from said magnetic composition.

公开(公告)号：WO1990012392A1

公开(公告)日：1990-10-18

申请号：PCT/JP1990000453

申请日：1990-04-04

Applicant: HITACHI MAXELL, LTD. ,  KAWARAI, Seigi ,  YOSHIDA, Kenichiro ,  KATO, Akira

Inventor： HITACHI MAXELL, LTD.

IPC: G11B05/714

CPC classification number: G11B5/735 ,  G11B5/714

Abstract: A magnetic recording medium in which a magnetic coating is applied to one surface of a support member and a back coating layer is applied to the other surface thereof. The magnetic coating contains a metallic magnetic powder having a major axis diameter of smaller than 0.2 mu m, and aninorganic powder having a Mohs' hardness of greater than 5. The back coating layer contains an inorganic powder having a Mohs's hardness of greater than 5, and it has a particle size smaller than the major axis diameter of the metallic magnetic powder. The magnetic recording medium is featured by high-density recording, high output and sufficiently suppressed noise that are required of small and high-picture-quality video tapes. The magnetic recording medium is of the type of a tape such as a magnetic tape having a magnetic layer and a back layer, with a total thickness made up of support member, magnetic coating and back coating layer of smaller than 14 mu m, which is wound.

Abstract translation: 将磁性涂层施加到支撑构件的一个表面和背涂层的磁记录介质施加到其另一表面。 磁性涂层含有长轴直径小于0.2μm的金属磁性粉末和莫氏硬度大于5的无机粉末。背涂层含有莫氏硬度大于5的无机粉末， 并且其粒径小于金属磁性粉末的长轴直径。 磁记录介质具有高密度记录，高输出和足够抑制的小和高画质视频磁带所需的噪声。 磁记录介质是具有磁性层和背层的磁带的类型，其总厚度由小于14μm的支撑构件，磁性涂层和背涂层构成，其总厚度为 伤口。

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：EP0145026A3

公开(公告)日：1986-02-05

申请号：EP84115484

申请日：1984-12-14

Applicant: Saiteku Corporation

Inventor： Takahashi, Yasunori

IPC: G11B05/716 ,  G11B05/66 ,  G11B05/845 ,  G11B05/714

CPC classification number: G11B5/716 ,  G11B5/66 ,  Y10S428/90 ,  Y10T428/256 ,  Y10T428/257

Abstract: A film type multilayer magnetic recording medium comprised of a film applied to a substratum in which coating film needle-shaped magnetic grains are orientated with their longitudinal axes perpendicular to the film surface in a multilayer state and having a film thickness of 1.1 to 2.0 times the average length of the grains, has an excellent property, because the angular ratio (Br Bs) of both horizontal and vertical components respectively are 0.6 or more. As a result, it is possible to attain a high density recording. The film type multilayer magnetic recording medium of the present inventions is manufactured by applying a fluid film forming material, in which neddle-shaped magnetic grains are dispersed to form a coating film having the thickness of 1.1 to 2.0 times the average length of the magnetic grains on a substratum, and then drying or hardening the film forming material in a magnetic field orientated perpendicularly toward the film surface.