Two-Step Magnetic Coating for Anti-Counterfeiting Security
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for creating security printed images with optical illusivity lack complexity and are easily counterfeitable, as they primarily produce static patterns that do not change effectively with angle or light direction, failing to provide the desired level of optical illusivity and security.
Innovation Solution
A two-step method involving the application of a first magnetic coating to a substrate, followed by alignment using a magnetic or electric field, and subsequent application of a second coating with different magnetic field orientation, allowing for the creation of complex images with relative movement and color changes when viewed from different angles or tilted.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single coating with magnetic particles is applied to create a security image, then the manufacturing process is simple, but the optical illusivity and security level are insufficient
Solution Approach 1:
The security image is divided into multiple coating layers, each containing magnetic particles that can be independently aligned by magnetic fields. This segmentation allows each layer to contribute different optical effects, thereby enhancing overall security while maintaining manageable manufacturing complexity through modular processing
Solution Approach 2:
Multiple coating layers are applied sequentially, with each subsequent layer nested over the previous ones. The magnetic particles in each layer are aligned by applied magnetic fields during or after application, creating complex three-dimensional optical structures that enhance security through layered complexity
2Reliability
If magnetic particles are aligned in a single coating layer, then the alignment process is straightforward, but the optical illusivity effect is limited
Solution Approach 1:
The invention extends the alignment process from two-dimensional planar alignment in a single layer to three-dimensional alignment across multiple layers. Magnetic particles are aligned not only within each layer but also in relation to other layers through sequential magnetic field application, creating complex spatial arrangements that enhance optical illusivity
Solution Approach 2:
The alignment process is made dynamic by applying magnetic fields at different stages of coating application and curing. Magnetic particles can be aligned in the liquid state before curing, and additional layers can be aligned after previous layers have set, allowing for dynamic control of particle orientation to create enhanced optical effects
3Illumination intensity
If conventional pigments are used in the coating, then the manufacturing cost is low, but the reflectance and color brightness are reduced
Solution Approach 1:
The invention changes the fundamental parameter of pigment type from conventional ground pigments to magnetic flake particles. These flake particles have inherent optical properties that provide higher reflectance and color brightness. The magnetic properties of these particles enable alignment control, adding functionality while the flakes themselves can be produced through established metallurgical processes
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
This method produces optically illusive images with enhanced security features, as the two distinct features appear to move synergistically, making them more difficult to counterfeit and providing a higher degree of optical illusivity.
Implementation Method 1
exposing the coated surface to a magnetic or electric field so as to align at least some of the flaked material
Implementation Method 2
dielectric material may be alignable in an electric field
Implementation Method 3
substrates painted or printed with color-shifting flaked pigments show change of color when viewed at different angles
Data Source
Figure 1~2d
Figure 3a~4d
Figure 5a~6b
AI summary
A two-step method of making of a security printed image is disclosed and includes coating of the surface of a substrate with a predetermined image shape with an ink containing flaked magnetic pigment in a predetermined concentration, exposing a wet printed image to a magnetic field to align magnetic particles in a predetermined manner, allowing the ink to cure, and coating the substrate with a second printed image on the top of the first image. The second printed image with the same or different image shape is printed with another ink containing clear or dyed ink vehicle mixed with flaked magnetic pigment in a low concentration, exposed to the magnetic field of the same or different configuration as the first printed image and cured until the ink is dry.