Patent US5368948A successfully refreshed from Google Patents.
US5368948A
Expired / Lapsed
US
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Magnetic materials for security applications
Assignee: Meto International GmbH
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Filing: 1993-04-09
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Granted: 1994-11-29
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Expires: 2013-04-09
Abstract
Abstract A tag or marker is disclosed which comprises a substrate; an `active` magnetic material which is a soft magnetic material having a high magnetic permeability and a low coercive force; and a deactivating material which is a hard or semi-hard magnetic material having a moderate or high coercive force and a moderate magnetic permeability, whereby the deactivating material, when subjected to a sufficiently high magnetising force, is able to clamp the magnetic properties of the `active` material so as to deactivate the `active` material. The tag or marker is characterised in that the deactivating material is formed by an electrodeposition process, and in that the deactivating layer is nickel.
Inventors
- 👤 Dafydd G. Davies
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 10:24
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/22; G08B13/24; G08B13/2402; G08B13/2405; G08B13/2408; G08B13/2411; G08B13/2414; G08B13/2417; G08B13/2428; G08B13/2437; G08B13/2442; H; H01; H01F; H01F41/00; H01F41/14; H01F41/24; H01F41/26; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12389; Y10T428/12396; Y10T428/12465
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
122 words
A magnetically active tag or marker which comprises a substrate; an `active` magnetic material which is a soft magnetic material having a high magnetic permeability and a low coercive force; and a deactivating material which is a hard or semi-hard magnetic material having a moderate or high coercive force and a moderate magnetic permeability, whereby the deactivating material, when subjected to a sufficiently high magnetizing force, is able to clamp the magnetic properties of the `active` material so as to deactivate the `active` material, characterized in that said deactivating material consists of nickel with a columnar crystal grain structure and substantially isotropic magnetic properties in the plane of said substrate, said deactivating material being formed by electrodeposition, electroforming or electroless chemical deposition.
Claim 2
Dependent Claim
122 words
A magnetically active tag or marker which comprises a substrate; an `active` magnetic material which is a soft magnetic material having a high magnetic permeability and a low coercive force; and a deactivating material which is a hard or semi-hard magnetic material having a moderate or high coercive force and a moderate magnetic permeability, whereby the deactivating material, when subjected to a sufficiently high magnetizing force, is able to clamp the magnetic properties of the `active` material so as to deactivate the `active` material, characterized in that said deactivating material consists of nickel with a columnar crystal grain structure and substantially isotropic magnetic properties in the plane of said substrate, said deactivating material being formed by electrodeposition, electroforming or electroless chemical deposition.
Claim 3
Dependent Claim
49 words
A tag or marker as claimed in claim 1, characterised in that said deactivating material is formed as a discontinuous foil or layer or as a plurality of islands carried by a substrate, by means of an electrodeposition process in which selective deposition is achieved by a masking technique.
Claim 4
Dependent Claim
35 words
A tag or marker as claimed in claim 1, characterized in that said deactivating material is planar and has a columnar grain structure and substantially isotropic magnetic properties in the plane of said deactivating material.
Claim 5
Dependent Claim
27 words
A tag or marker as claimed in 1, characterised in that said columnar grain structure is coated with a thin layer of a planar crystal grain structure.
Claim 6
Dependent Claim
28 words
A tag or marker as claimed in claim 1, characterised in that said deactivating material is subjected to a deformation process after being formed by an electrodeposition method.
Claim 7
Dependent Claim
26 words
A tag or marker as claimed in claim 1, characterised in that said deactivating material has been subjected to a stamping, rolling, pressing or embossing process.
Claim 8
Dependent Claim
23 words
A tag or marker as claimed in claim 1, characterised in that said deactivating material is subjected to mechanical deformation or cold working.
Claim 9
Dependent Claim
28 words
A tag or marker as claimed in claim 1, characterised in that a portion of the area of said deactivating material has been subjected to said deformation process.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-11-28 | 1998-05-30 | 1998-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-11-28 | 2002-05-30 | 2002-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-11-28 | 2006-05-30 | 2006-11-29 | $7700.00 | Window Closed / Lapsed |