Coating Composition for Optical Substrates with Enhanced Antifouling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current coating technologies for optical materials and touch panels lack improved surface antifouling properties, specifically in terms of water repellency, oil repellency, and ease of dirt removal.
Innovation Solution
A coating composition comprising polyhedral oligomeric silsesquioxane and an acrylate polymer, applied in a specific proportion to achieve enhanced water and oil repellency, with a sliding angle of 4.0 degrees or less, and a surface arithmetic mean roughness of 2.5 nm or less, while maintaining high transmittance and optical clarity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional coating technologies are used on optical materials, then the coating can be applied, but the surface antifouling property is insufficient and water/oil repellency is poor
Solution Approach 1:
The patent uses a composite coating system combining fluorinated polyol polymer and polyhedral oligomeric silsesquioxane (POSS). This composite material approach creates synergistic effects where the fluorinated polymer provides base hydrophobicity and the POSS units enhance surface energy distribution, achieving superior water and oil repellency that neither component could achieve alone.
Solution Approach 2:
The patent modifies the chemical composition parameters of the coating by incorporating fluorinated groups (-CF3, -CF2-) and silsesquioxane units. These parameter changes in molecular structure and surface chemistry directly improve the surface antifouling properties and reduce liquid adhesion while maintaining optical clarity.
2Object-affected harmful factors
If the coating composition is optimized for water repellency, then sliding angle decreases, but the coating complexity increases
Solution Approach 1:
The patent applies local quality by creating specific microenvironments on the coating surface through POSS units. These units distribute surface energy non-uniformly at the molecular level, creating low-energy zones that facilitate liquid droplet rolling off. The fluorinated polymer matrix provides uniform hydrophobic background while POSS units create localized enhancement zones.
3Illumination intensity
If the coating surface is made smoother to reduce roughness, then transmittance improves, but the antifouling property may be compromised
Solution Approach 1:
The patent resolves this contradiction by operating at the nanoscale dimension. The POSS units create surface features at the molecular level (nanodimension) that provide antifouling functionality without creating visible surface roughness. This nanoscale structuring maintains optical smoothness for high transmittance while providing sufficient surface energy variation for liquid repellency.
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 coating technology provides superior antifouling properties with reduced liquid droplet sliding angles and contact angles, ensuring effective water and oil repellency, ease of dirt removal, and maintaining high transmittance and optical clarity.
Implementation Method 1
the coating contains: (a) a polyhedral oligomeric silsesquioxane; and (b) an acrylate polymer having a structural unit represented by the following general formula (II)
Implementation Method 2
a solvent for dissolving the polyhedral oligomeric silsesquoxane and the acrylate polymer
Implementation Method 3
a coating step of applying the coating composition to the surface of a substrate and removing the solvent
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Provided is a coating technology additionally excellent in, for example, water repellency, oil repellency, and ease of dirt removal. An article having a coating on a substrate, in which the coating contains: (a) a polyhedral oligomeric silsesquioxane; and (b) an acrylate polymer having a structural unit represented by the following general formula (II): where Ra represents a hydrogen atom or a methyl group, Rf represents -CH2-(CF2)q-CF3 or -CH(CF3)2, and q represents an integer of 0 to 8.