EP0095070A2
Expired / Lapsed
EP
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Magnetic recording media
Assignee: Toshiba Corp
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Filing: 1983-05-04
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Granted: —
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Expires: 2003-05-04
Abstract
Abstract Disclosed is a magnetic recording medium, characte-, rized in that 5 to 100 parts by weight of hexagonal ferrite particles having an average particle diameter of 0.01 to 0.2 µm and 100 parts by weight of ferromagnetic particles having a saturation magnetization of 70 to 220 emu/g and an average particle diameter larger than that of the hexagonal ferrite particles are dispersed in a resinous binder.
Inventors
- 👤 Toshihiko Tokyo Shibaura Denki K.K. Oguchi
- 👤 Hirohisa Tokyo Shibaura Denki K.K. Kato
- 👤 Moriyasu Tokyo Shibaura Denki K.K. Wada
- 👤 Toshimitsu Tokyo Shibaura Denki K.K. Asano
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 04:03
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/706; G11B5/70626; G11B5/70642; G11B5/70678; G11B5/714; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/25; Y10T428/256; Y10T428/257; Y10T428/258
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
63 words
A magnetic recording medium, comprising 5 to 100 parts by weight of hexagonal ferrite particles having an average particle diameter of 0.01 to 0.2 pm, and 100 parts by weight of ferromagnetic particles having a saturation magnetization of 70 to 220 emu/g and an average particle diameter larger than that of the hexagonal ferrite particles, which particles are dispersed in a resinous binder.
Claim 2
Dependent Claim
63 words
A magnetic recording medium, comprising 5 to 100 parts by weight of hexagonal ferrite particles having an average particle diameter of 0.01 to 0.2 pm, and 100 parts by weight of ferromagnetic particles having a saturation magnetization of 70 to 220 emu/g and an average particle diameter larger than that of the hexagonal ferrite particles, which particles are dispersed in a resinous binder.
Claim 3
Dependent Claim
70 words
The magnetic recording medium according to Claim 1. wherein said hexagonal ferrite is selected from the group consisting of Ba-ferrite, Sr-ferrite, Ca-ferrite, Pb-ferrite and substituted Ba-ferrite represented by the following formula: (wherein, M means at least one element selected from the group consisting of Co, Ti, Zn, Ni, Mn, In, Cu, Ge and Nb, and m and n stand respectively for intergers of 0 to 0.2 and 5.4 to 6.0).
Claim 4
Dependent Claim
18 words
The magnetic recording medium according to Claim 2, wherein said hexagonal ferrite is Ba-ferrite or the substituted Ba-ferrite.
Claim 5
Dependent Claim
24 words
The mgnetic recording medium according to Claim 1, wherein the average particle diameter of said hexagonal ferrite particles ranges from 0.05 to 0.1 µm.
Claim 6
Dependent Claim
24 words
The magnetic recording medium according to Calim 1, wherein said hexagonal ferrite has coersive force (i H c) of from 600 to 2000 Oe.
Claim 7
Dependent Claim
24 words
The magnetic recording medium according to Calim 1, wherein said hexagonal ferrite has coersive force (i H c) of from 600 to 2000 Oe.
Claim 8
Dependent Claim
22 words
The magnetic recording medium according to Calim 5, wherein said hexagonal ferrite has coersive force (iHc) of from 700 to 1500 Oe.
Claim 9
Dependent Claim
22 words
The magnetic recording medium according to Calim 5, wherein said hexagonal ferrite has coersive force (iHc) of from 700 to 1500 Oe.
Claim 10
Dependent Claim
49 words
The magnetic recording medium according to Claim 1, wherein said ferromagnetic particles are particles of a metal selected from Fe, Ni, Co and Cr; particles of alloys made of two or more of Fe, Ni, Co and Cr; magnetite particles; Y-ferrite particles; Co-modified magnetite particles; or Co-modified Y-ferrite particles.
Claim 11
Dependent Claim
16 words
The magnetic recording medium according to Claim 7, wherein said ferromagnetic particles are particles of Y-ferrite.
Claim 12
Dependent Claim
21 words
The magnetic recording medium according to Claim 7, wherein said ferromagnetic particles have a saturation magnetization of 70 to 220 emu/g.
Claim 13
Dependent Claim
21 words
The magnetic recording medium according to Claim 7, wherein said ferromagnetic particles have a saturation magnetization of 75 to 150 emu/g.
Claim 14
Dependent Claim
27 words
The magnetic recording medium according to Claim 1, wherein the average particle diamerter of said ferromagnetic particles is controlled within the range of 0.05 to 1 µm.
Claim 15
Dependent Claim
24 words
The magnetic recording medium according to Claim 1, wherein the amount of said hexagonal ferrite particles ranges from 10 to 50 parts by weight.
References Cited (Backward Citations)
No citation records indexed.
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