GB1490517A - Magnetisable storage media - Google Patents
Magnetisable storage mediaInfo
- Publication number
- GB1490517A GB1490517A GB4876073A GB4876073A GB1490517A GB 1490517 A GB1490517 A GB 1490517A GB 4876073 A GB4876073 A GB 4876073A GB 4876073 A GB4876073 A GB 4876073A GB 1490517 A GB1490517 A GB 1490517A
- Authority
- GB
- United Kingdom
- Prior art keywords
- magnetisable
- orientation
- medium
- iron
- oct
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/62—Record carriers characterised by the selection of the material
- G11B5/68—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent
- G11B5/70—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer
Landscapes
- Paints Or Removers (AREA)
Abstract
1490517 Magnetisable storage media EMI Ltd 21 Oct 1974 [19 Oct 1973] 48760/73 Heading B2E [Also in Division B6] A method of making a magnetisable storage medium for a security document or device comprises dispersing magnetisable material particles e.g. acicular ferric oxide, chromium oxide, iron, cobalt, iron-cobalt alloy or nickel iron alloy, in a binder e.g. polyvinylchloride, polyvinylacetate, polyvinylacetals, polyester resins, polyamides, polyacrylic resins and rubber, and an additive, coating the mixture on a substrate e.g. paper, card or plastics tape and drying so that the medium has a selected particle proportion less than the maximum containable in the coating layer and less than 35% but with an orientation ratiohigher than at the maximum proportion. The term orientation ratio refers to the ratio of magnetic resonances in the plane of a layer of the medium, in the longitudinal and transverse directions relative to the orientation. The oriented particles may be in the form of a watermark as described or claimed in Speceifications 1331604 or 1486888.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB4876073A GB1490517A (en) | 1974-10-21 | 1974-10-21 | Magnetisable storage media |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB4876073A GB1490517A (en) | 1974-10-21 | 1974-10-21 | Magnetisable storage media |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1490517A true GB1490517A (en) | 1977-11-02 |
Family
ID=10449809
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB4876073A Expired GB1490517A (en) | 1974-10-21 | 1974-10-21 | Magnetisable storage media |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB1490517A (en) |
-
1974
- 1974-10-21 GB GB4876073A patent/GB1490517A/en not_active Expired
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed | ||
PCNP | Patent ceased through non-payment of renewal fee |