Security element comprising magnetic materials having the same remanence and a different coercive field intensity
View Patent ↗The invention relates to a security element for protecting documents of value, which has magnetic material. Furthermore, the invention relates to a document of value, a transfer material and method for producing such security elements and documents of value as well as a method and an apparatus for checking such a security element or document of value. According to the invention the security element has at least two magnetic materials, wherein the magnetic materials have different coercive field strengths and are applied onto and/or incorporated in the security element in such a manner that their remanence is equally high.
1. Security element for securing objects of value, wherein the security element comprises:
magnetic materials and at least two different magnetic areas, which have different coercive field strengths,
wherein a first magnetic area has a first magnetic material, the first magnetic material having a first coercive field strength, and a second magnetic area has a second magnetic material, the second magnetic material having a second coercive field strength,
wherein the second coercive field strength is different than the first coercive field strength, and
wherein the remanences of the magnetic areas are essentially equal.
2. Security element according to claim 1 , wherein the different magnetic materials have at least one of different layer thicknesses and different concentrations.
3. Security element according to claim 1 , wherein the magnetic materials are present in certain areas of the security element.
4. Security element according to claim 1 , wherein the security element is a security thread or a planchet.
5. Document of value with a security element, said security element comprising:
magnetic materials and at least two different magnetic areas, which have different coercive field strengths,
wherein a first magnetic area has a first magnetic material, the first magnetic material having a first coercive field strength, and a second magnetic area has a second magnetic material, the second magnetic material having a second coercive field strength,
wherein the second coercive field strength is different than the first coercive field strength, and
wherein the remanences of the magnetic areas are essentially equal.
6. Document of value according to claim 5 , wherein the different magnetic materials have at least one of different layer thicknesses and different concentrations.
7. Document of value according to claim 5 , wherein the magnetic materials are present in certain areas of the security element.
8. Document of value according to claim 5 , wherein the security element is a label.
9. Document of value according to claim 5 , wherein the document of value is a security paper, a security document or a product packaging.
10. Transfer material for producing a security element, comprising:
a carrier material on which at least two different magnetic materials are disposed to form at least two different magnetic areas, said magnetic areas having different coercive field strengths, wherein a first magnetic area has a first magnetic material, the first magnetic material having a first coercive field strength, and a second magnetic area has a second magnetic material, the second magnetic material having a second coercive field strength,
wherein the second coercive field strength is different than the first coercive field strength, and
wherein the remanences of the magnetic areas are essentially equal.
11. Transfer material according to claim 10 , wherein the carrier material is in the form of a hot stamping foil.
12. Method for producing an object of value or security element, comprising the steps:
providing a substrate,
applying at least two magnetic materials onto the substrate as at least two different magnetic areas, said areas having different coercive field strengths,
wherein a first magnetic area has a first magnetic material, the first magnetic material having a first coercive field strength, and a second magnetic area has a second magnetic material, the second magnetic material having a second coercive field strength,
wherein the second coercive field strength is different than the first coercive field strength,
and wherein the remanences of the magnetic areas are essentially equal.
13. Method for checking an object of value with a security element, said security element comprising at least two different magnetic areas which have different coercive field strengths, wherein a first magnetic area has a first magnetic material, the first magnetic material having a first coercive field strength, and a second magnetic area has a second magnetic material, the second magnetic material having a second coercive field strength, wherein the second coercive field strength is different than the first coercive field strength, and wherein the remanences of the magnetic areas are essentially equal, comprising the steps:
magnetizing the magnetic materials in the magnetic areas by means of a first magnetic field, whose field strength is higher than the highest coercive field strength of the magnetic materials,
magnetizing the magnetic materials in the magnetic areas by means of at least one second magnetic field, whose field strength is higher than the lowest coercive field strength and lower than the next higher coercive field strength of the magnetic materials, and
determining the changes of the orientation of the magnetic field emanating from the security element.
14. Method according to claim 13 , wherein the orientation of the second magnetic field is contrary to the orientation of the first magnetic field.
15. Method according to claim 13 , wherein the second magnetic field is an alternating field.
16. Method according to claim 13 , wherein after the checking, the magnetic materials are magnetized by means of a third magnetic field, whose field strength is higher than the highest coercive field strength of the magnetic materials.
17. Apparatus for checking an object of value with a security element, said security element having at least two different magnetic areas which have different coercive field strengths, wherein a first magnetic area has a first magnetic material, the first magnetic material having a first coercive field strength, and a second magnetic area has a second magnetic material, the second magnetic material having a second coercive field strength, wherein the second coercive field strength is different than the first coercive field strength, and wherein the remanences of the magnetic areas are essentially equal, comprising:
a first magnetizing device, whose field strength is higher than the highest coercive field strength of the magnetic materials in the magnetic areas,
at least one second magnetizing device, whose field strength is higher than the lowest coercive field strength, and lower than the next higher coercive field strength of the magnetic materials, and
a magnet sensor with an evaluation device, which is arranged to enable determination of changes of the orientation of the magnetic field emanating from the security element.
18. The apparatus according to claim 17 , wherein the orientation of the magnetic field of the second magnetizing device is contrary to the orientation of the magnetic field of the first magnetizing device.
19. The apparatus according to claim 17 , wherein the second magnetizing device comprises an electromagnet, which is arranged to generate an alternating field.
20. The apparatus according to claim 17 , including a third magnetizing device, whose field strength is higher than the highest coercive field strength of the magnetic materials, disposed downstream from the magnet sensor.