EP0089609A2
Expired / Lapsed
EP
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Magnetic recording medium and method of manufacturing a magnetic recording medium
Assignee: Panasonic Holdings Corp
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Filing: 1983-03-15
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Granted: —
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Expires: 2003-03-15
Abstract
Abstract In manufacturing a magnetic recording medium by vapour-depositing a magnetic metal film (10) containing Co-Cr with 70 - 90 weight % Co as host material on a high polymer substrate (1), with or without intermediate layer(s) (8,9) inbetween, by making the high polymer substrate run around a cylindrical can (2), conditions are selected such that linear expansion coefficient of the substrate is 1.0 x 10 -5 -2.9 x 10 -5 /°C and temperature of the can surface is 150° - 300°C; thereby normal or inverse curling of the resultant recording medium is substantially eliminated.
Inventors
- 👤 Ryuji Sugita
- 👤 Kenji Kanai
- 👤 Seishi Sasaki
- 👤 Ken Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 19:22
CPC Classifications
H; H01; H01F; H01F41/00; H01F41/14; H01F41/20; G; G11; G11B; G11B5/00; G11B5/84; G11B5/851
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
72 words
Magnetic recording medium, comprising a magnetic film (10) vapour-deposited on a high polymer substrate (1), with or without intermediate layer(s) (8,9) inbetween, characterized in that said magnetic film (10) contains Co-Cr as host material, the constituent of Co lying in the range of 70 - 90 weight %, and that the linear expansion coefficient of said substrate lies in the range of 1.0 x 10 -5 - 2.9 x 10 -5 /°C.
Claim 2
Dependent Claim
72 words
Magnetic recording medium, comprising a magnetic film (10) vapour-deposited on a high polymer substrate (1), with or without intermediate layer(s) (8,9) inbetween, characterized in that said magnetic film (10) contains Co-Cr as host material, the constituent of Co lying in the range of 70 - 90 weight %, and that the linear expansion coefficient of said substrate lies in the range of 1.0 x 10 -5 - 2.9 x 10 -5 /°C.
Claim 3
Dependent Claim
32 words
Magnetic recording medium according to claim 1, wherein said magnetic film (10) is a vertical magnetization film, characterized in that as an intermediate layer (9) there is provided a vapour-deposited Ti film.
Claim 4
Dependent Claim
26 words
Magnetic recording medium according to claim 2, characterized in that there is provided a permalloy film (8) between said substrate (1) and said Ti film (9).
Claim 5
Dependent Claim
27 words
Magnetic recording medium according to claim 2, characterized in that there is provided a permalloy film (8) between said Ti film (9) and said magnetic film (10).
Claim 6
Dependent Claim
109 words
Method of manufacturing a magnetic recording medium by vapour- depositing a magnetic film on a high polymer substrate, with or withouth intermediate layer(s) inbetween, wherein said vapour-deposition is made with said high polymer substrate running around a cylindrical can, characterized in that said magnetic film contains Co-Cr as host material, wherein the constituent of Co lies in the range of 70 - 90 weight %, that the linear expansion coefficient of said substrate is selected in the range of 1.0 x 10" - 2.9 x 10 -5 /°C, and that the temperature of the outer surface of said cylindrical can is selected in the range of 150 - 300°C.
Claim 7
Dependent Claim
109 words
Method of manufacturing a magnetic recording medium by vapour- depositing a magnetic film on a high polymer substrate, with or withouth intermediate layer(s) inbetween, wherein said vapour-deposition is made with said high polymer substrate running around a cylindrical can, characterized in that said magnetic film contains Co-Cr as host material, wherein the constituent of Co lies in the range of 70 - 90 weight %, that the linear expansion coefficient of said substrate is selected in the range of 1.0 x 10" - 2.9 x 10 -5 /°C, and that the temperature of the outer surface of said cylindrical can is selected in the range of 150 - 300°C.
Claim 8
Dependent Claim
56 words
Method according to claim 5, characterized in that said intermediate layer is a Ti film being vapour-deposited making said high polymer substrates run around said cylindrical can which is heated to a temperature in a range of 10 - 120°C, and said magnetic film is a vertical magnetization film having Co and Cr as host materials.
Claim 9
Dependent Claim
52 words
Method according to claim 6, characterized in that the method further comprises the step that prior to the vapour-deposition of said Ti film, a permalloy film is vapour-deposited by making said high polymer substrate run around said cylindrical can which is heated to a temperature in the range of 120 - 260°C.
Claim 10
Dependent Claim
51 words
Method according to claim 6, characterized in that the method further comprises the step that after the vapour-deposition of said Ti film, a permalloy film is vapour-deposited by making said high polymer substrate run around said cylindrical can which is heated to a temperature in the range of 120 - 260°C.
References Cited (Backward Citations)
No citation records indexed.
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