EMBOSSING LACQUER FOR MICRO-OPTICAL SECURITY ELEMENTS

• US 20100109317A1
• Filed: 02/13/2008
• Published: 05/06/2010
• Est. Priority Date: 02/14/2007
• Status: Active Grant

• Current Assignee: Giesecke & Devrient (Giesecke & Devrient GmbH)
• Original Assignee: Giesecke & Devrient GmbH
• Inventors: Dichtl, Marius, Hoffmüller, Winfried
• Granted Patent: US 8,557,369 B2
• Time in Patent Office: Days
• US Class Current: 283/91
• CPC Class Codes: B41M 3/14 Security printing securities B42D25/29
• CPC Class Codes: B42D 2035/20 Optical effects
• CPC Class Codes: B42D 2035/44 Miniaturised markings
• CPC Class Codes: B42D 25/29 Securities; Bank notes
• CPC Class Codes: B42D 25/324 Reliefs
• CPC Class Codes: B42D 25/41 using electromagnetic radiation B42D25/435 takes precedence
• CPC Class Codes: C08L 2312/00 Crosslinking
• CPC Class Codes: C09D 11/101 Inks specially adapted for printing processes involving curing by wave energy or particle radiation, e.g. with UV-curing following the printing
• CPC Class Codes: C09D 133/14 of esters containing halogen, nitrogen, sulfur or oxygen atoms in addition to the carboxy oxygen
• CPC Class Codes: C09D 133/16 Homopolymers or copolymers of esters containing halogen atoms
• CPC Class Codes: C09D 5/28 for wrinkle, crackle, orange-peel, or similar decorative effects
• CPC Class Codes: G02B 3/0012 characterised by the manufacturing method
• CPC Class Codes: Y10T 428/24355 Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]

Abstract

The present invention relates to a highly refractive embossing lacquer for producing micro-optic arrangements which contains at least one binding agent which has at least one radiation-curing compound system consisting of one or more organic compounds. The highly refractive embossing lacquer is characterized in that at least a portion of the organic compounds of the radiation-curing compound system consists of molecules with at least one polarizable element, so that a polymeric material with a refractive index of greater than 1.5 is formed upon radiation curing. The invention also relates to a security element which is produced with at least one micro-optic authenticity feature. Micro-optic authenticity features according to the present invention permit the production of security elements that are so thin that they can be easily incorporated into value documents.

Claims

1-37. -37. (canceled)

38. A security element for marking the authenticity of objects of value with at least one micro-optic authenticity feature, the micro-optic authenticity feature comprising a first micro-optic arrangement with a multiplicity of focusing elements which are present in a first grid, and a second micro-optic arrangement with a multiplicity of microstructures which are present in a second grid, the first and second arrangements being disposed such that the microstructures of the second arrangement are observable as magnified upon viewing through the focusing elements of the first arrangement, wherein the first and/or second micro-optic arrangements are produced from a highly refractive embossing lacquer which contains at least one binding agent which has at least one radiation-curing compound system comprising one or more organic compounds, at least a portion of said organic compounds of the radiation-curing compound system comprising molecules with at least one polarizable element, so that a polymeric material with a refractive index of greater than 1.5 is formed upon radiation curing of the compound system.

39. The security element according to claim 38, wherein the polarizing element comprises at least one element which is selected from the group consisting of S, Cl, Br, I and mixtures thereof.

40. The security element according to claim 38, wherein the radiation-curing compound system is a UV-curing compound system.

41. The security element according to claim 38, wherein the embossing lacquer contains a polymerization initiator.

42. The security element according to claim 38, wherein the radiation-curing compound system comprises a compound system curable by electron beams.

43. The security element according to claim 38, wherein the radiation-curing compound system is polyreactable radically or cationically.

44. The security element according to claim 38, wherein the compounds of the radiation-curing compound system are used as monomers and/or prepolymers.

45. The security element according to claim 38, wherein a polymeric material with a refractive index of greater than 1.6, preferably greater than 1.7, is formed upon said curing.

46. The security element according to claim 38, wherein the compounds of the radiation-curing compound system are self-crosslinking compounds.

47. The security element according to claim 46, wherein the self-crosslinking compounds of the radiation-curing compound system comprise molecules of the same or a different chemical identity.

48. The security element according to claim 46, wherein self-crosslinking compounds of the compound system comprise at least one acrylate.

49. The security element according to claim 46, wherein self-crosslinking compounds of the compound system comprise at least one epoxide.

50. The security element according to claim 46, wherein self-crosslinking compounds of the compound system comprise at least one episulfide.

51. The security element according to claim 38, wherein the radiation-curing compound system comprises a first compound and a second compound which can be reacted with the first compound so as to crosslink.

52. The security element according to claim 51, wherein the first compound of the radiation-curing compound system and/or the second compound of the radiation-curing compound system comprise molecules of the same chemical identity or a different chemical identity.

53. The security element according to claim 51, wherein the second compound comprises a thiol and/or a polythiol.

54. The security element according to claim 51, wherein the first compound comprises an isocyanate.

55. The security element according to claim 51, wherein the first compound is or contains an olefinically unsaturated compound.

56. The security element according to claim 51, wherein the first compound comprises an epoxide.

57. The security element according to claim 51, wherein the first compound comprises an episulfide.

58. The security element according to claim 38, wherein all compounds of the radiation-curing compound system comprise molecules with at least one polarizable element.

59. The security element according to claim 38, wherein at least a portion of the compounds of the radiation-curing compound system comprise molecules with at least two polarizable elements.

60. The security element according to claim 38, wherein the embossing lacquer contains refractive index enhancing nanoparticles.

61. The security element according to claim 60, wherein the nanoparticles are nanopigments.

62. The security element according to claim 60, wherein the nanoparticles are polymerized into the embossing lacquer.

63. The security element according to claim 38, wherein the embossing lacquer contains reactive dyes.

64. The security element according to claim 38, wherein the embossing lacquer also contains further components customary in embossing lacquers.

65. The security element according to claim 38, including at least one further authenticity feature which is checkable by machine and/or visually.

66. The security element according to claim 38, wherein the first and second grids of the micro-optic authenticity feature have a fixed geometrical relation.

67. The security element according to claim 38, wherein the microstructures of the second arrangement of the micro-optic authenticity feature are present in the form of microcharacters or micropatterns.

68. The security element according to claim 38, wherein the microstructures and/or the focusing elements are configured to be colored.

69. The security element according to claim 68, wherein the microstructures comprise microstructure elements of different color.

70. The security element according to claim 38, wherein the security element has a total thickness of 20 to 50 μ

m.

71. The security element according to claim 38, wherein the security element is configured as a transfer element or a security thread.

72. A method for producing a security element according to claim 38, wherein the microstructures and/or the focusing elements are applied by techniques of semiconductor technology, or by micro-contact printing (μ

CP) or microgravure printing.

73. Use of a security element according to claim 38 for marking the authenticity of a product.

74. A data carrier, such as a value document, comprising a security element according to claim 38.