Security Element Laminate With Cohesive-Failure Delamination Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing laminates with security elements enclosed between two layers suffer from differential adhesive forces at boundary surfaces, making them vulnerable to manipulation and forgery through targeted delamination or peeling.
Innovation Solution
A laminate design featuring a security element with a detachment layer, a replication layer, a reflective layer, and an adhesive layer that can be split by a tensile force, ensuring cohesive failure rather than adhesive failure, thereby enhancing protection against manipulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the security element is enclosed between two layers joined in a material-bonding manner, then the adhesive force is high and the security element is protected from damage, but different boundary surfaces with different adhesive forces form at the boundary surfaces of the security element, making the laminate vulnerable to targeted delamination or peeling
Solution Approach 1:
The adhesive layer is divided into multiple sub-layers (first adhesive sub-layer, second adhesive sub-layer, third adhesive sub-layer) with different adhesive forces. The first adhesive sub-layer has a first adhesive force, the second adhesive sub-layer has a second adhesive force, and the third adhesive sub-layer has a third adhesive force. This segmentation ensures that no single boundary surface has uniformly high adhesive force, preventing targeted delamination while maintaining overall structural integrity.
Solution Approach 2:
Different regions of the adhesive layer are assigned different adhesive forces. The first adhesive sub-layer is arranged at a first boundary surface with a first adhesive force, the second adhesive sub-layer is arranged at a second boundary surface with a second adhesive force, and the third adhesive sub-layer is arranged at a third boundary surface with a third adhesive force. This local differentiation ensures that boundary surfaces have varying adhesive characteristics, making manipulation attempts more difficult while preserving the protective function.
2Reliability
If the adhesive layer is made strong to prevent delamination, then the security element is better protected, but the laminate becomes more vulnerable to detection of manipulation attempts
Solution Approach 1:
The adhesive layer is segmented into multiple sub-layers with different adhesive forces, creating a non-uniform adhesive structure. This segmentation means that if manipulation occurs, the delamination will occur at specific boundaries where the adhesive force is lowest, making the manipulation detectable through visual inspection or measurement of adhesive strength at different locations.
Solution Approach 2:
The adhesive layer has locally differentiated adhesive forces at different boundary surfaces. This local quality variation creates predictable failure points that can be detected. If an attempt is made to manipulate the laminate, the delamination will occur at the weakest adhesive boundaries, providing a detectable pattern that indicates manipulation rather than uniform strength throughout.
3Force
If the adhesive layer is designed to fail cohesively under tensile force, then the peel force is increased and manipulation is complicated, but the adhesive layer structure becomes more complex
Solution Approach 1:
The adhesive layer is divided into multiple sub-layers (first, second, and third adhesive sub-layers) with different adhesive forces. This segmentation creates multiple potential failure planes within the adhesive layer. When tensile force is applied, the cohesive failure occurs within the adhesive layer structure, requiring higher peel force to separate the layers completely. The segmented structure provides multiple resistance points that increase the overall peel force.
Solution Approach 2:
The adhesive layer is designed as a composite structure with multiple sub-layers having different material properties and adhesive forces. This composite adhesive layer combines the benefits of multiple materials to achieve high peel force resistance while maintaining the necessary flexibility and adhesion characteristics. The composite structure provides inherent complexity that increases the force required for manipulation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The laminate design significantly complicates undetectable detachment or reuse of the security element, making manipulation attempts more difficult and increasing the peel force required for separation, thus improving forgery resistance.
Implementation Method 1
the adhesive layer adheres to the record layer and the detachment layer adheres to the cover layer or the adhesive layer adheres to the cover layer and the detachment layer adheres to the record layer
Implementation Method 2
the adhesive layer of the security element can be split up by a tensile force exerted on the security element by the record layer and the cover layer. The adhesive layer of the laminate according to the invention and of the laminate that can be obtained by the method according to the invention can in particular be split up by means of a cohesive failure
Data Source
AI summary
A laminate (1) including a security element (20), which is laminated in between a record layer (11) and a cover layer (12), wherein an adhesive layer (25) adheres to the record layer (11) and a detachment layer (21) adheres to the cover layer (12) or the adhesive layer (25) adheres to the cover layer (12) and the detachment layer (21) adheres to the record layer (11) and the laminate (1) is designed such that the adhesive layer (25) of the security element (20) can be split up by a tensile force exerted on the security element (20) by the record layer (11) and the cover layer (12), as well as to a method for producing a laminate (1).