Photochromic Coating Composition for High Color Density Spectacle Lenses
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing photochromic coatings for optical articles, such as spectacle lenses, struggle to achieve high color density when developing color upon light irradiation.
Innovation Solution
A coating composition for optical articles containing a photochromic compound and two or more (meth)acrylates, specifically a non-cyclic difunctional methacrylate with a molecular weight of 500 or more and a non-cyclic tri- or higher functional (meth)acrylate, which together form a photochromic layer capable of high color density development.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If conventional photochromic coatings are used, then the coating can be applied to optical articles, but the color density upon light irradiation is insufficient
Solution Approach 1:
The patent changes the molecular weight parameter of the difunctional methacrylate (using 500 or more) and the functionality parameter of the (meth)acrylate components to achieve high color density while maintaining reliable photochromic performance. This parameter optimization allows the photochromic compound to develop color at high density upon light irradiation.
Solution Approach 2:
The patent uses a composite coating composition containing a photochromic compound combined with specific (meth)acrylates (non-cyclic difunctional methacrylate with molecular weight 500 or more and non-cyclic tri- or higher functional (meth)acrylate). This composite material approach enables both high color density and excellent photochromic performance to be achieved simultaneously.
2Illumination intensity
If the photochromic layer is optimized for high color density, then color development improves, but the molecular structure complexity increases
Solution Approach 1:
The patent optimizes specific parameters of the (meth)acrylate components (molecular weight of 500 or more for difunctional methacrylate, and tri- or higher functionality) to achieve high color density without excessive molecular structure complexity. The parameter ranges are carefully selected to balance performance and complexity.
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 composition enables the formation of a photochromic layer that develops color at a high density upon light irradiation, while maintaining excellent photoresponsiveness.
Implementation Method 1
A photochromic compound is a compound having a property (photochromic properties) of developing color under irradiation with light in a wavelength range having photoresponsiveness and fading under non irradiation.
Data Source
AI summary
A coating composition for an optical article containing a photochromic compound and two or more (meth)acrylates, the two or more (meth)acrylates containing a non-cyclic difunctional methacrylate having a molecular weight of 500 or more and a non-cyclic tri- or higher functional (meth)acrylate.