UV LED Curing for Resilient Floor Covering Adhesion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing resilient floor coverings with digitally printed decorative layers using solvent-free UV curable inks face issues with chemical compatibility, leading to rapid delamination when directly laminated between polymer layers, necessitating the use of auxiliary connecting layers.
Innovation Solution
The method involves using UV LED sources with a narrow spectral emission range of 345-420 nm to incompletely cure the UV curable ink, allowing for homogeneous curing and controlled cross-linking, which enables durable adhesion between the decorative layer and the support and wear layers without the need for an auxiliary connecting layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If UV curable ink is completely cured before lamination, then the decorative layer gains sufficient strength and cohesion, but adhesion to polymer layers deteriorates due to chemical incompatibility
Solution Approach 1:
The patent applies partial curing of the UV curable ink instead of complete curing. The ink is cured to a degree that provides sufficient cohesion and handling strength, but stops before full cross-linking occurs. This partial state maintains chemical compatibility with polymer layers for good adhesion, while still providing enough strength for processing. The curing is controlled to achieve this intermediate state where the decorative layer is stable enough to handle but not fully cross-linked, preventing delamination issues.
2Productivity
If traditional UV sources with broad spectrum are used, then curing speed is high, but curing homogeneity deteriorates due to surface over-curing
Solution Approach 1:
The patent uses UV LED sources that emit in the UV-A range (345-420 nm) with a relatively narrow spectral bandwidth. This provides more uniform energy distribution across the ink layer thickness compared to broad-spectrum sources. The UV-A radiation penetrates more evenly through the UV curable ink, achieving homogeneous curing throughout the layer rather than just at the surface. This local quality improvement in spectral distribution ensures consistent cross-linking from surface to substrate.
3Reliability
If auxiliary connecting layers are used to prevent delamination, then adhesion reliability improves, but device complexity and production cost increase
Solution Approach 1:
The patent removes the auxiliary connecting layer from the multilayer structure by controlling the curing degree of the UV curable ink. Instead of adding a separate adhesive layer to ensure compatibility, the solution extracts this intermediate layer and relies on the partially cured ink itself to provide both cohesion and adequate adhesion to polymer layers. This simplification maintains reliability while reducing structural complexity and production costs.
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 approach ensures a resilient floor covering with improved adhesion, flexibility, and print quality, while maintaining sufficient cohesion within the decorative layer, and reduces heat generation, allowing for the use of thin decorative layer support films.
Implementation Method 1
UV curing the printed decorative layer; wherein the UV curing is carried out with UV LED sources having a spectral emission in the range of 345 - 420 nm
Data Source
Figure 1A~1D
Figure 2A~2D
Figure 3A~3D
AI summary
A method for producing a printed resilient floor covering comprises: digitally printing a decorative layer onto the top surface of a support layer or the bottom surface of a wear layer with a UV curable ink; UV curing the printed decorative layer; laminating the support layer and the transparent wear layer together so that the printed decorative layer is sandwiched between the support layer and the transparent wear layer. Alternatively, the method comprises: digitally printing a decorative layer onto a decorative layer support film with a UV curable ink; UV curing the printed decorative layer on the decorative layer support film; laminating a support layer, the decorative layer support film and a transparent wear layer together, so that the decorative layer support film with the printed decorative layer is sandwiched between the support layer and the transparent wear layer. In both embodiments, the UV curing is carried out with UV LED sources having a spectral emission in the range of 345 - 420 nm, so that during lamination, the UV curable ink is still incompletely cured.