Curable Composition Viscosity Refractive Index Trade-off
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing curable compositions for optical lenses face challenges in achieving a high refractive index while maintaining low viscosity, particularly with the addition of high refractive index particles like zirconia, which increases viscosity and complicates handling and dispersion stability.
Innovation Solution
A curable composition comprising an alicyclic epoxy compound and a cationically polymerizable compound with a binaphthyl group, along with a monofunctional cationically polymerizable aromatic compound, which reduces viscosity while maintaining a high refractive index, making it suitable for optical lens applications.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of stationary object
If high refractive index particles (zirconia) are added to improve the refractive index, then the refractive index increases, but the viscosity increases and handling becomes difficult
Solution Approach 1:
The patent changes the chemical composition parameters by selecting specific alicyclic epoxy compounds with particular molecular structures and functionalities that inherently provide low viscosity. By adjusting the ratio of component (A) alicyclic epoxy compound to component (B) polymerization catalyst within specific ranges, the composition achieves optimal balance between low viscosity and high refractive index without requiring particle additives.
Solution Approach 2:
The patent creates a composite curable composition system combining specific alicyclic epoxy compounds (component A) with polymerization catalysts (component B). This composite approach uses molecular-level composition design rather than particle blending, achieving high refractive index through the inherent optical properties of the alicyclic epoxy compound structure while maintaining low viscosity through careful selection of molecular weight and functional groups.
2Duration of action of stationary object
If high refractive index particles (zirconia) are added to improve the refractive index, then the refractive index increases, but the process becomes complicated requiring fine particle preparation and dispersion stability control
Solution Approach 1:
The patent extracts and eliminates the need for high refractive index particles (zirconia) from the composition system. Instead of using particulate fillers that require complex preparation and dispersion processes, the invention achieves high refractive index through the molecular structure of the alicyclic epoxy compound itself, thereby removing the associated process complexity entirely.
Solution Approach 2:
The patent changes from a particle-filled system to a molecular-composition system by selecting alicyclic epoxy compounds with specific structural parameters (cyclic structure, functional groups, molecular weight) that inherently provide high refractive index. This parameter change transforms the approach from additive-based to composition-based refractive index enhancement, simplifying the entire process.
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 achieves a refractive index of 1.58 or greater at 589 nm and 1.55 or greater at 940 nm, with a viscosity of 30 Pa·s or less, enhancing liquid feeding properties and coatability, and is suitable for both optical lenses and near-infrared applications.
Implementation Method 1
a curable composition containing an alicyclic epoxy compound (A) and a cationically polymerizable compound (B) having a binaphthyl group
Data Source
AI summary
[Problem]To provide a curable composition capable of achieving reduction in viscosity while having a high refractive index when formed into a cured product.[Solution]Disclosed is a curable composition containing an alicyclic epoxy compound (A) and a cationically polymerizable compound (B) having a binaphthyl group.The curable composition preferably contains a monofunctional cationically polymerizable aromatic compound (C), preferably has a viscosity of 30 Pa·s or less at 25° C., and preferably has a refractive index of 1.58 or greater at a wavelength 589 nm when cured.[Selected Drawing] None