Decorative Sheet Ridge Coating for Low Gloss and Smooth Feel
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing decorative sheets lack a balance between low gloss and smooth feel, often compromising on one for the other, and do not adequately address durability and processability.
Innovation Solution
A decorative sheet design featuring a surface protective layer with a specific uneven structure, including ridge-like protrusions and controlled peak heights and roughness, achieved through a coating process using an ionizing radiation curable resin with acrylate as a main component, which provides a low gloss and smooth tactile experience.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a matting agent is added to the surface protective layer to achieve low gloss, then the gloss is reduced, but the smooth feel is compromised
Solution Approach 1:
The invention changes the physical parameters of the surface protective layer by controlling the protruding peak height Rpk to be 0.5 μm or more and the average length RSm of roughness curve elements to be 10 μm or more. This parameter control creates an uneven structure that achieves low gloss without compromising smooth feel, as the controlled roughness patterns scatter light effectively while maintaining tactile smoothness.
Solution Approach 2:
The invention introduces curvature through the ridge portions with controlled protruding peak heights and smooth transitions. The sinusoidal waveform cross-section and controlled Rpk values create curved surface features that provide optical scattering for low gloss while the smooth curvature maintains tactile comfort, resolving the contradiction between matte appearance and smooth touch.
2Reliability
If the surface protective layer is made thicker to improve durability, then scratch resistance improves, but the smooth feel deteriorates
Solution Approach 1:
The invention optimizes the thickness parameter of the surface protective layer to be 2 μm or more and less than 15 μm. Within this thickness range, the layer provides sufficient scratch resistance and durability while maintaining the smooth feel. The controlled uneven structure parameters (Rpk ≥ 0.5 μm, RSm ≥ 10 μm) ensure that even at these thicknesses, the surface maintains tactile smoothness while providing the necessary protective function.
3Illumination intensity
If the protruding peak height is increased to enhance low gloss effect, then the gloss is reduced, but the smooth feel is compromised
Solution Approach 1:
The invention precisely controls the protruding peak height Rpk to be 0.5 μm or more but does not specify an upper limit beyond the context of maintaining smooth feel. This controlled parameter range creates sufficient optical scattering for low gloss effect while preventing excessive surface roughness that would compromise tactile smoothness. The combination with RSm ≥ 10 μm ensures the right balance between optical and tactile properties.
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 solution results in a decorative sheet with low gloss and a smooth feel, enhanced scratch resistance, and improved processability, while maintaining durability and aesthetic appeal.
Implementation Method 1
a coating process using an ionizing radiation curable resin with acrylate as a main component
Implementation Method 2
an absorption spectrum obtained from Fourier infrared spectrometry of the surface protective layer has a ratio I1095/I1725 of 0.65 or more
Data Source
AI summary
The disclosure provides a decorative sheet having a low gloss and imparting a smooth feel. There is provided a decorative sheet including a primary film layer, and a surface protective layer provided to one side of the primary film layer, wherein the surface protective layer has a surface provided with an uneven structure including a plurality of ridge portions each protruding in a ridge-like shape; the uneven structure of the surface protective layer have a protruding peak height Rpk of less than 3.5 μm; and an absorption spectrum obtained from Fourier infrared spectrometry of the surface protective layer has a ratio I1095/I1725 of 0.65 or more, that is a ratio of a maximum value I1095 in the wavenumber range of 1085 to 1105 cm−1 to a maximum value 1725 in the wavenumber range of 1715 to 1735 cm−1.