Optically variable security threads and stripes

Patent metadata

Field	Value
Publication number	US-9844969-B2
Application number	US-201214418483-A
Country	US
Kind code	B2
Filing date	Aug 1, 2012
Priority date	Aug 1, 2012
Publication date	Dec 19, 2017
Grant date	Dec 19, 2017

Abstract

In the field of protection of value documents and value commercial goods, the present disclosure relates to the field of security threads or stripes to be incorporated into or onto security documents, and security documents having security threads or stripes. The security threads or stripes include i) first optically variable layer imparting a first different color impression at different viewing angles, ii) second optically variable layer imparting a second different color impression at different viewing angles, iii) first color constant layer having a color matching color impression of the first or second optically variable layer at a first viewing angle, iv) second color constant layer having a color matching color impression of the first or second optically variable layer at a second viewing angle, and v) a substrate. The layers are jointly visible from one side of the security thread or stripe.

First claim

The invention claimed is:

1. A security thread or stripe comprising:
i) a first optically variable layer imparting a first differing color impression at different viewing angles and being made of an optically variable composition comprising a plurality of optically variable pigments;
ii) a second optically variable layer imparting a second differing color impression at different viewing angles and being made of an optically variable composition comprising a plurality of optically variable pigments,
iii) a first color constant layer having a color matching the color impression of the first or second optically variable layer at a first viewing angle;
iv) a second color constant layer having a color matching the color impression of the first or second optically variable layer at a second viewing angle; and
v) a substrate,
wherein the first differing color impression is different from the second differing color impression,
wherein the first optically variable layer and the second optically variable layer either comprise one or more gaps in the form of indicia, or comprise indicia made of the optically variable compositions,
wherein the first optically variable layer is disposed on top of the first color constant layer and/or the second color constant layer, and the second optically variable layer is disposed on top of the first color constant layer and/or the second color constant layer,
wherein the first color constant layer is adjacent to the second color constant layer,
wherein the first optically variable layer, the second optically variable layer, the first color constant layer and the second color constant layer are jointly visible from one side of the security thread or stripe,
wherein, when viewed from the top, the first and second color constant color layers are within different optically variable layers, or the first and second optically variable layers are within different color constant layers, and
wherein the first and second color constant layers are visible at the same angle.

2. The security thread or stripe according to claim 1 , wherein the first optically variable layer is not adjacent to the second optically variable layer.

3. The security thread or stripe according to claim 1 , wherein the first optically variable layer is adjacent to the second optically variable layer.

4. The security thread or stripe according to claim 1 , wherein the first viewing angle under which the first color constant layer has a color matching the color impression of the first or second optically variable layer is the same angle as the second viewing angle under which the second color constant layer has a color matching the color impression of the first or second optically variable layer.

5. The security thread or stripe according to claim 1 , wherein the first viewing angle under which the first color constant layer has a color matching the color impression of the first or second optically variable layer is different from the second viewing angle under which the second color constant layer has a color matching the color impression of the first or second optically variable layer.

6. The security thread or stripe according to claim 1 , wherein at least a part of the plurality of optically variable pigments consists of thin film interference pigments, magnetic thin film interference pigments, interference coated pigments, cholesteric liquid crystal pigments and mixtures thereof.

7. The security thread or stripe according to claim 6 , wherein the thin film interference pigments comprise a Fabry-Perot absorber/dielectric/reflector/dielectric/absorber multilayer structure.

8. The security thread or stripe according to claim 7 , wherein the reflector layer comprises a metal, metal alloy or combinations thereof; and/or
the dielectric layers independently comprise magnesium fluoride (MgF 2 ), silicium dioxide (SiO 2 ), or mixtures thereof; and/or
the absorber layers independently comprise chromium, nickel, a metal alloy, or mixtures thereof.

9. The security thread or stripe according to claim 7 , wherein the Fabry-Perot absorber/dielectric/reflector/dielectric/absorber multilayer structure is a multilayer structure consisting of Cr/MgF 2 /Al/MgF 2 /Cr.

10. The security thread or stripe according to claim 6 , wherein the magnetic thin film magnetic interference pigments comprise a 5-layer Fabry-Perot absorber/dielectric/reflector/dielectric/absorber multilayer structure wherein the reflector and/or the absorber is a magnetic layer.

11. The security thread or stripe according to claim 10 , wherein the magnetic thin film magnetic interference pigments comprise a 7-layer Fabry-Perot absorber/dielectric/reflector/magnetic/reflector/dielectric/absorber multilayer structure.

12. The security thread or stripe according to claim 11 , wherein the 7-layer Fabry-Perot absorber/dielectric/reflector/magnetic/reflector/dielectric/absorber layer is a multilayer structure of Cr/MgF 2 /Al/Ni/Al/MgF 2 /Cr.

13. The security thread or stripe according to claim 10 , wherein the reflector layers independently comprise metals, metal alloys, or combinations thereof; and/or
the dielectric layers independently comprise magnesium fluoride (MgF 2 ), silicium dioxide (SiO 2 ), or mixtures thereof; and/or
the absorber layers comprise chromium, nickel, a metal alloy, or mixtures thereof; and/or
the magnetic layer comprises nickel (Ni), iron (Fe), cobalt (Co), or mixtures thereof.

14. The security thread or stripe according to claim 1 , wherein the second color constant layer is disposed in one or more covering areas on top of the first color constant layer.

15. The security thread or stripe according to claim 1 , wherein the first color constant layer is longitudinally adjacent to the second color constant layer.

16. The security thread or stripe according to claim 1 , wherein the first color constant layer and the second color constant layer are alternately arranged in a transverse direction.

17. The security thread or stripe according to claim 1 , further comprising a substrate comprising a plastic, polymer, composite material, metal, metalized material, or mixtures thereof.

18. The security thread or stripe according to claim 1 further comprising one or more protective layers.

19. The security thread or stripe according to claim 1 , further comprising one or more additional layers comprising an adhesive layer, a lacquer, a machine readable layer, a hiding layer, or combinations thereof.

20. The security thread or stripe according to claim 19 , wherein the machine readable layer comprises a machine readable material comprising a magnetic material, luminescent material, electrically conductive material, infrared-absorbing material, or mixtures thereof.

21. The security thread or stripe according to claim 1 , wherein the first and the second optically variable layer consists of radiation curable compositions, thermal drying compositions or any combination thereof.

22. The security thread or stripe according to claim 1 , wherein the indicia comprise symbols, alphanumeric symbols, motifs, geometric patterns, letters, words, numbers, logos, drawings, or combinations thereof.

23. The security thread or stripe according to claim 1 having a width between about 0.5 mm and about 30 mm.

24. A process for making the security thread or stripe recited in claim 1 , the process comprising:
a) applying the first color constant layer onto the substrate,
b) applying the second color

Assignees

• Ritter Gebhard
• Demange Raynald
• Degott Pierre
• Ye Zhongdong
• Wu Yuanqi
• Sun Fangyi
• Wang Weiru
• Li Xiang
• Sicpa Holding Sa
• Zhongchao Special Security Technology Co Ltd
• China Banknote Sicpa Security Ink Co Ltd
• China Banknote Printing & Minting Corp

Inventors

• Ritter Gebhard
• Demange Raynald
• Degott Pierre
• Ye Zhongdong
• Wu Yuanqi
• Sun Fangyi
• Wang Weiru
• Li Xiang

Classifications

• B42D25/355

  Security threads · CPC title

• G09F3/0292

  tamper indicating labels · CPC title

• B41M3/148 Primary

  Transitory images, i.e. images only visible from certain viewing angles · CPC title

• B42D25/45

  Associating two or more layers · CPC title

• G09F19/14

  displaying different signs depending upon the view-point of the observer · CPC title