Hard Coat Layer Composition for Scratch and Crack Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hard coat layer compositions for plastic bases, while providing good scratch resistance, often compromise on crack resistance, and achieving both properties at a high level is challenging due to their trade-off relationship.
Innovation Solution
A hard coat layer-forming composition combining metal oxide particles, an organic silicon compound with a small alkylene group, another organic silicon compound with a larger alkylene group, and a glycoluril crosslinking agent, optimized in terms of molecular content and particle size, to form a hard coat layer with enhanced scratch and crack resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a conventional hard coat layer composition containing metal oxide particles and γ-glycidoxypropyltrimethoxysilane is used, then scratch resistance is improved, but crack resistance deteriorates
Solution Approach 1:
The patent uses a composite material system combining metal oxide particles with a dual-component organic silicon compound system (γ-glycidoxypropyltrimethoxysilane and glycidoxypropylmethyldimethoxysilane) to achieve both scratch resistance and crack resistance. The composite formulation allows the hard coat layer to simultaneously gain hardness from metal oxide particles and flexibility/crack resistance from the combined organic silicon compounds.
Solution Approach 2:
The patent changes the chemical composition parameters by introducing a specific ratio of γ-glycidoxypropyltrimethoxysilane (Formula 1) to glycidoxypropylmethyldimethoxysilane (Formula 2), where the latter component with its additional methyl group provides modified crosslinking characteristics that improve crack resistance while maintaining scratch resistance through controlled hydrolysis and condensation reactions.
2Strength
If the hard coat layer is made harder to improve scratch resistance, then crack resistance decreases due to reduced flexibility
Solution Approach 1:
The patent applies local quality by creating different functional zones within the hard coat layer through the dual-component organic silicon compound system. The γ-glycidoxypropyltrimethoxysilane provides hard, scratch-resistant regions while the glycidoxypropylmethyldimethoxysilane creates more flexible, crack-resistant regions, resulting in a heterogeneous structure that simultaneously achieves both properties.
Solution Approach 2:
By combining metal oxide particles (providing hardness) with a dual-component organic silicon compound system (providing flexibility and crack resistance), the patent creates a composite hard coat layer where the metal oxide phase provides scratch resistance while the organic silicon matrix provides flexibility and crack resistance, resolving the contradiction between hardness and flexibility.
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 effectively improves both scratch and crack resistance of the hard coat layer, achieving superior performance by balancing these properties, as demonstrated in the optical members formed using this composition.
Implementation Method 1
a component X that is at least one selected from the group consisting of an organic silicon compound represented by Formula (1), a hydrolysate thereof and a hydrolyzed condensate thereof
Implementation Method 2
a component X that is at least one selected from the group consisting of an organic silicon compound represented by Formula (1), a hydrolysate thereof and a hydrolyzed condensate thereof
Implementation Method 3
a glycoluril crosslinking agent represented by Formula (3), a hydrolysate thereof and a hydrolyzed condensate thereof
Data Source
AI summary
The present invention provides a hard-coat-layer-forming composition whereby a hard coat layer having excellent scratch resistance and cracking resistance can be formed, and an optical member. The hard-coat-layer-forming composition is a composition used to form a hard coat layer on a plastic substrate, and includes: metal oxide particles; at least one type of component X selected from the group consisting of an organic silicon compound represented by a predetermined formula, a hydrolysate thereof, and a hydrolytic condensate thereof; and at least one type of component Y selected from the group consisting of an organic silicon compound represented by a predetermined formula, a hydrolysate thereof, and a hydrolytic condensate thereof, and a glycoluril crosslinking agent, a hydrolysate thereof, and a hydrolytic condensate thereof.