Ink with cohesive failure and identification document including same

Abstract

The present invention provides identification documents with security features. For example, a document may include two or more inks that are designed to cohesively fail upon a de-lamination attack. A resulting failure pattern is preferably difficult to predict. The two or more inks are applied to an identification document including a core and laminate layer. At least one of the inks is characterized such that an adhesive strength of the ink to the core and an adhesive strength of the ink to the laminate layer is each greater than the cohesive strength of the ink itself. Thus, the ink rips apart in a somewhat random-like manner upon a de-lamination attack. The ink can be arranged in interwoven or interlocking patterns or in other desired patterns and locations.

1 . An identification document comprising:
 a core including a front surface and a back surface;   an over-laminate including a front surface and a back surface, the back surface of the over-laminate being adjacently positioned with said core front surface; and   ink provided on at least one of the front surface of the core and the back surface of the over-laminate, wherein the ink is characterized as having substantially the same degree of adhesion both to the front surface of the core and to the back surface of the over-laminate, and wherein the adhesion of the ink to the front surface of the core and the adhesion of the ink to the back surface of the over-laminate are each relatively stronger than a cohesive strength of the ink,   wherein the core comprises a synthetic sheet, the over-laminate comprises a polymer, and the core and the over-laminate are bonded at a temperature in the range of 220-240° F.   
     
     
         2 . An identification document comprising:
 a core including a front surface and a back surface;   an over-laminate including a front surface and a back surface, the back surface of the over-laminate being adjacently positioned with said core front surface; and   ink provided on at least one of the front surface of the core and the back surface of the over-laminate, wherein the ink is characterized as having substantially the same degree of adhesion both to the front surface of the core and to the back surface of the over-laminate, and wherein the adhesion of the ink to the front surface of the core and the adhesion of the ink to the back surface of the over-laminate are each relatively stronger than a cohesive strength of the ink,   wherein the ink is configured to arrange a steganographic message.   
     
     
         3 . The identification document of  claim 2 , wherein the steganographic message comprises a digital watermark. 
     
     
         4 . The identification document of  claim 3 , wherein the digital watermark comprises a calibration component. 
     
     
         5 . The identification document of  claim 2 , wherein the ink comprises at least one of an optically variable ink and a pearlescent ink. 
     
     
         6 . The identification document of  claim 5 , wherein the optically variable ink comprises a white pearlescent ink. 
     
     
         7 . The identification document of  claim 2 , wherein the ink comprises at least one of an ultraviolet pigment and an infrared pigment. 
     
     
         8 . An identification document comprising:
 a core including a front surface and a back surface;   an over-laminate including a front surface and a back surface, the back surface of the over-laminate being adjacently positioned with said core front surface; and   ink provided on at least one of the front surface of the core and the back surface of the over-laminate, wherein the ink is characterized as having substantially the same degree of adhesion both to the front surface of the core and to the back surface of the over-laminate, and wherein the adhesion of the ink to the front surface of the core and the adhesion of the ink to the back surface of the over-laminate are each relatively stronger than a cohesive strength of the ink,   wherein the ink is configured to arrange a steganographic message, the core comprises a synthetic sheet, the over-laminate comprises a polymer, and the core and the over-laminate are bonded at a temperature in the range of 220-240° F.   
     
     
         9 . An identification document comprising:
 a core including a front surface and a back surface;   an over-laminate including a front surface and a back surface, the back surface of the being adjacently positioned with said core front surface; and   two inks provided on at least one of the front surface of the core and the back surface of the over-laminate, wherein the two inks are characterized as having substantially the same degree of adhesion both to the front surface of the core and to the back surface of the over-laminate, and wherein the adhesion of the two inks to the front surface of the core and the adhesion of the two inks to the back surface of the over-laminate are each relatively stronger than a cohesive strength of the ink,   wherein a first ink of the two inks is in a first color and a second ink of the two inks is in a second color,   wherein the two inks are applied adjacently,   wherein the two inks cohesively fail upon an de-lamination attack, generating at least one of a color overlap and a color void in a de-lamination attacked document.   
     
     
         10 . An identification document comprising:
 a substrate including a front surface and a back surface;   an over-laminate including a front surface and a back surface, the back surface of the over-laminate being adjacently positioned with said substrate front surface;   a first ink provided on at least one of the front surface of the substrate and the back surface of the over-laminate, wherein the first ink forms a first semantic information; and   an optically variable element provided on at least one of the front surface of the substrate and the back surface of the over-laminate, wherein the optical variable element forms a second semantic information, and wherein the second semantic information comprises the first semantic information but is spatially offset from the first semantic information so as to provide at least one of a shading and a depth-effect for the first semantic information only when the identification document is viewed at a viewing angle associated with the optically variable element, wherein the at least one of a shading and a depth-effect produces a 3-D effect.   
     
     
         11 . A method of making an ink that is designed to cohesively fail, comprising:
 manipulating or selecting a resin used to bind the ink to a substrate material and a laminate material; and   if the ink or the resin is found to cohesively fail, investigating adhesion characteristics of the ink to the substrate material and the laminate material.   
     
     
         12 . A method of making an ink that is designed to cohesively fail, comprising:
 analyzing cohesive failure of ink resins;   mapping relative cohesive strength of the ink resins against adhesive strength of the ink resins to various substrate and laminate materials; and   determining a desired ink resin from such mapping.   
     
     
         13 . A method of making an ink that is designed to cohesively fail, comprising:
 identifying a resin material that has adhesion to a substrate and laminate material; and   using the resin material with color pigments to form the ink.   
     
     
         14 . A method of making a tamper-resistant identification document comprising:
 providing a core including a top surface;   providing a top laminate including a top surface and a bottom surface; and   providing two or more inks between the top surface of the core and the bottom surface of the top laminate, wherein the two or more inks are characterized as having substantially the same degree of adhesion both to the top surface of the core and to the bottom surface of the top laminate, and wherein the adhesion of the two or more inks to the top surface of the core and the adhesion of the two or more inks to the bottom surface of the top laminate are each relatively stronger than a cohesive strength of the ink,   wherein the two or more inks are formed in a pattern, the pattern including at least a plurality of intertwined or interlocking circles or mesh structures, and a first ink of the two or more inks comprises a first color and a second ink of the two or more inks comprises a second, different color,   wherein the two or more inks cohesively delaminate upon an intrusion attempt, resulting in portions of the plurality of intertwined or interlocking circles or mesh structures in the first and second colors adhering to the top surface of the core and portions of the plurality of intertwined or interlocking circles or mesh structures in the first and second colors adhering to the bottom surface of the top laminate, such that tampering is evident.