Aromatic Polyisocyanate Plastic Lens Weather Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Plastic lenses formed with polyisocyanate compounds containing aromatic rings suffer from poor weather resistance, despite efforts to enhance optical characteristics with additives like benzophenone derivatives and phenol compounds.
Innovation Solution
A composition comprising 100 parts of a polyisocyanate compound with an aromatic ring, 0.5 to 5.0 parts of a benzophenone compound with a hydroxyl group on the ortho position, and 0.5 to 5.0 parts of a phenol compound, when polymerized, significantly improves the weather resistance of the plastic lens.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a polyisocyanate compound having an aromatic ring is used to form a plastic lens, then the refractive index is improved, but the weather resistance deteriorates
Solution Approach 1:
The patent changes the chemical parameters by introducing specific stabilizer compounds (benzophenone derivative and phenol compound) into the polyisocyanate composition. These stabilizers are added in controlled amounts (0.01-5 wt% each) to modify the chemical properties of the resin system, enabling it to resist weathering while maintaining its high refractive index characteristics from the aromatic polyisocyanate
Solution Approach 2:
The patent creates a composite material system by combining the aromatic polyisocyanate compound with stabilizer compounds (benzophenone derivative and phenol compound). This composite approach allows the base material to provide high refractive index while the added stabilizers provide weather resistance, resolving the contradiction between optical performance and durability
2Reliability
If stabilizer compounds are added to improve weather resistance, then the weather resistance is improved, but the initial coloration increases
Solution Approach 1:
The patent optimizes the concentration parameters of stabilizer compounds, specifying that the benzophenone derivative and phenol compound should each be present at 0.01-5 wt% of the total composition. This controlled parameter range ensures sufficient weather resistance while minimizing the impact on initial optical clarity and coloration of the lens material
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 resulting plastic lens exhibits excellent weather resistance, making it suitable for applications such as spectacle, camera, projector, and telescope lenses, with improved durability and resistance to discoloration.
Implementation Method 1
a plastic lens having excellent weather resistance, formed by polymerization of a composition containing a polyisocyanate compound having an aromatic ring and a polythiol compound
Data Source
AI summary
A plastic lens having excellent weather resistance, formed by polymerization of a composition containing a polyisocyanate compound having an aromatic ring and a polythiol compound is provided. The plastic lens is formed by polymerization of a composition that contains 100 parts by mass in total of (A) a polyisocyanate compound containing a polyisocyanate compound having an aromatic ring and (B) a polythiol compound, from 0.5 to 5.0 parts by mass of (C) a benzophenone compound having a hydroxyl group on at least the ortho position, and from 0.5 to 5.0 parts by mass of (D) a phenol compound.