EP0125478A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Magnetic record disk with internal servo track
Assignee: International Business Machines Corp
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Filing: 1984-04-09
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Granted: —
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Expires: 2004-04-09
Abstract
Abstract A servo track in the form of a patterned thin metallic film (15; 25) is disposed between a magnetic record medium (14; 24) and a dielectric substrate (12; 22). The dielectric substrate (12; 22) can be in the form of a coating on a metallic substrate (11; 21). Where the magnetic record medium is composed of magnetic particles bound in a matrix, the matrix and the dielectric substrate are preferably composed of the same material. An additional layer (26,) of dielectric material may be disposed between the metallic servo track film (25) and the magnetic record medium (24).
Inventors
- 👤 Sol Krongelb
- 👤 Lubomyr Taras Romankiw
- 👤 Robert Alan Scranton
- 👤 David Allen Thompson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 17:24
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/58; G11B5/596; G11B5/012; G11B5/74; G11B5/82
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
54 words
A magnetic record disk comprising a magnetic record medium (14; 24) supported on a dielectric substrate (12; 22), the magnetic record medium having a flat surface, the record disk being characterised by a patterned metallic servo track film (15; 25) disposed between the magnetic record medium (14; 24) and the dielectric substrate (12; 22).
Claim 2
Dependent Claim
54 words
A magnetic record disk comprising a magnetic record medium (14; 24) supported on a dielectric substrate (12; 22), the magnetic record medium having a flat surface, the record disk being characterised by a patterned metallic servo track film (15; 25) disposed between the magnetic record medium (14; 24) and the dielectric substrate (12; 22).
Claim 3
Dependent Claim
25 words
A record disk as claimed in claim 1, in which the patterned metallic servo track film (15; 25) is from 0.005 to 0.1 microns thick.
Claim 4
Dependent Claim
21 words
A record disk as claimed in claim 2, in which the patterned metallic servo track film (15;25) is 0.01 microns thick.
Claim 5
Dependent Claim
48 words
A record disk as claimed in any preceding claim, in which the magnetic record medium (14; 24) is composed of magnetic particles bound in a matrix material and the dielectric substrate (12; 22) is composed of a material having physical characteristics similar to those of the matrix material.
Claim 6
Dependent Claim
23 words
A record disk as claimed in claim 4, in which the dielectric substrate is composed of the same material as the matrix material.
Claim 7
Dependent Claim
37 words
A record disk as claimed in claim 5, in which the magnetic record medium (14; 24) is composed of magnetic particles bound in an epoxy-phenolic matrix and the dielectric substrate (12; 22) is composed of epoxy-phenolic material.
Claim 8
Dependent Claim
37 words
A record disk as claimed in claim 5, in which the magnetic record medium (14; 24) is composed of magnetic particles bound in a matrix of polyurethane and the dielectric substrate (12; 22) is composed of polyurethane.
Claim 9
Dependent Claim
37 words
A record disk as claimed in any of claims 1 to 3, in which the dielectric substrate (12; 22) is composed of polyimide and the magnetic record medium (14; 24) is composed of sputtered magnetic iron oxide.
Claim 10
Dependent Claim
32 words
A record disk as claimed in any preceding claim, including an additional layer -(26) of dielectric material disposed between the patterned metallic servo track film (25) and the magnetic record medium (24).
Claim 11
Dependent Claim
31 words
A record disk as claimed in any preceding claim, in which the dielectric substrate (12; 22) takes the form of a coating and is supported on a metallic substrate (11; 21).
Claim 12
Dependent Claim
13 words
A record disk as claimed in any preceding claim, which is substantially rigid.
References Cited (Backward Citations)
No citation records indexed.
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