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EP0135322A1
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An optical magnetic recording member
Assignee: Ulvac Inc
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Filing: 1984-07-31
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Granted: —
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Expires: 2004-07-31
Abstract
Abstract There is provided an optical magnetic recording member comprising a perpendicular magnetic film (2), a reflection film (3) backing the perpendicular magnetic film (2), and a substrate (1) supporting these films (2, 3). The perpendicular magnetic film (2) is a mixture-type perpendicular magnetic film comprising a mixture of a ferromagnetic metal Me and a dielectric.
Inventors
- 👤 Kyuzo Nakamura
- 👤 Yoshifumi Ota
- 👤 Tsutomu Asaka
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 15:37
CPC Classifications
G; G11; G11B; G11B11/00; G11B11/10; G11B11/105; G11B11/10582; G11B11/10586; G11B11/10589; H; H01; H01F; H01F10/00; H01F10/08; H01F10/10; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
55 words
An optical magnetic recording member comprising a perpendicular magnetic film (2), a reflection film (3) backing the perpendicular magnetic film (2), and a substrate (1) supporting these films (2, 3), characterised in that the perpendicular magnetic film (2) is a mixture-type perpendicular magnetic film comprising a mixture of a ferromagnetic metal Me and a dielectric.
Claim 2
Dependent Claim
55 words
An optical magnetic recording member comprising a perpendicular magnetic film (2), a reflection film (3) backing the perpendicular magnetic film (2), and a substrate (1) supporting these films (2, 3), characterised in that the perpendicular magnetic film (2) is a mixture-type perpendicular magnetic film comprising a mixture of a ferromagnetic metal Me and a dielectric.
Claim 3
Dependent Claim
26 words
An optical magnetic recording member as claimed in claim 1, wherein the substrate (1) is transparent and is provided on the mixture-type perpendicular magnetic film (2).
Claim 4
Dependent Claim
24 words
An optical magnetic recording member as claimed in claim 1, wherein the substrate (1) is nontransparent and is provided behind the reflection film (3).
Claim 5
Dependent Claim
32 words
An optical magnetic recording member as claimed in claim 2, wherein a transparent thermal insulation material film (4) is interposed between the transparent substrate (1) and the mixture-type perpendicular magnetic film (2).
Claim 6
Dependent Claim
23 words
An optical magnetic recording member as claimed in claim 4, wherein the transparent insulation material film (4) is made of Si0 2 .
Claim 7
Dependent Claim
59 words
An optical magnetic recording member as claimed in any preceding claim, wherein the ferromagnetic metal Me is a ferromagnetic metal such as Fe, Co, Ni or an alloy thereof, and the dielectric is a dielectric substance such as any oxide of Co, Fe, Ni, Al, Cr, Ti, Zr, Si, or a fluoride such as M g F 2 .
Claim 8
Dependent Claim
33 words
An optical magnetic recording member as claimed in any preceding claim, wherein the reflection film (3) is made of a non-magnetic metallic material such as Al, Cu, Ag, Au, Pt, or the like.
Claim 9
Dependent Claim
34 words
An optical magnetic recording member as claimed in any of claims 1 to 6, wherein the reflection film (3) is made of a soft magnetic material such as permalloy, Fe, Co or the like.
Claim 10
Dependent Claim
28 words
An optical magnetic recording member as claimed in any of claims 1 to 6, wherein the reflection film (3) is a metallic perpendicular magnetic film of Co-Cr, Tb-Fe.
Claim 11
Dependent Claim
39 words
An optical magnetic recording member as claimed in any preceding claim, wherein the mixture-type perpendicular magnetic film (2) is of such a film thickness that makes the reflection factor thereof substantially the minimum at a predetermined reproducing laser wavelength.
References Cited (Backward Citations)
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