Patterned Pressure-Sensitive Adhesive for Polarizer Light Leakage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional polarizer adhesives face challenges with dimensional stability under high temperature and humidity due to differences in molecular structures, leading to birefringence and light leakage, and existing solutions either reduce cuttability or durability.
Innovation Solution
A pressure-sensitive adhesive with patterned hard and soft areas, where the soft areas have a lower storage modulus than the hard areas, formed within a single plane to maintain adhesion and inhibit dimensional changes, using a composition including acryl resin, multi-functional acrylate, and photo initiator, and controlled curing to achieve optimal storage modulus ratios.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the adhesive is designed to cause high creep and easy deformation under external stress to provide stress relaxation characteristic, then light leakage is reduced, but cuttability or workability of the adhesive is significantly reduced
Solution Approach 1:
The adhesive layer is designed with non-uniform thickness, having a first thickness in a first region and a second thickness in a second region. This local variation in thickness allows different regions to exhibit different mechanical properties, enabling the adhesive to provide stress relaxation while maintaining adequate cuttability and workability during manufacturing.
2Reliability
If the storage modulus of the adhesive is increased to minimize light leakage, then hardness is improved, but initial adhesion is greatly reduced and durability is reduced at high temperature or humidity
Solution Approach 1:
The adhesive layer has non-uniform thickness that creates local variations in mechanical properties. Regions with different thicknesses provide different degrees of stress relaxation and adhesion, allowing the system to maintain both light leakage prevention and adequate initial adhesion without requiring excessively high storage modulus throughout the entire adhesive layer.
3Device complexity
If the adhesive layer has uniform storage modulus, then manufacturing is simplified, but dimensional stability under high temperature and humidity is insufficient due to stress concentration
Solution Approach 1:
The adhesive layer is designed with non-uniform thickness, creating regions with different mechanical properties. This local variation allows the adhesive to distribute and relax stresses more effectively under high temperature and humidity conditions, improving dimensional stability while maintaining a relatively simple single-layer structure.
4Productivity
If the adhesive is made softer to improve cuttability and workability, then manufacturing efficiency is improved, but light leakage increases due to insufficient hardness
Solution Approach 1:
The adhesive layer has non-uniform thickness with different regions providing different functional characteristics. Softer regions with greater thickness improve cuttability and workability for high manufacturing efficiency, while other regions provide sufficient hardness to prevent light leakage, thus resolving the contradiction between productivity and light leakage prevention.
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 solution effectively prevents light leakage and maintains durability and adhesion under high-temperature and high-humidity conditions, while ensuring excellent productivity and light transmission uniformity.
Implementation Method 1
using a composition including acryl resin, multi-functional acrylate, and photo initiator, and controlled curing
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Provided are a pressure-sensitive adhesive having excellent durability and reliability under high-temperature or high-humidity conditions, adhesion strength, workability, removability, and the ability to inhibit light leakage; a method for preparing the pressure-sensitive adhesive; a polarizer including the pressure-sensitive adhesive; and a liquid crystal display incorporating the polarizer.