Adhesive Member for Flexible Displays with Temperature-Resilient Tg
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Flexible display devices require adhesive members with high adhesion and folding reliability to maintain performance across various temperatures and usage conditions, but existing solutions fail to provide consistent stability and durability.
Innovation Solution
An adhesive member formed from a resin composition comprising (meth)acrylate monomers, urethane (meth)acrylate oligomers, and photoinitiators, with specific properties such as a glass transition temperature range of -70°C to -30°C, high 180° peel force, and controlled stress relaxation ratios, applied using inkjet printing for uniformity and adhesion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional adhesive resins are used in flexible display devices, then the adhesive member can be formed, but the adhesion reliability and folding reliability are insufficient across various temperatures
Solution Approach 1:
The patent applies parameter changes by carefully controlling the glass transition temperature (Tg) of the adhesive resin within a specific range of -70°C to -30°C. This parameter optimization enables the adhesive to maintain appropriate viscosity and adhesion properties across a wide temperature range, achieving both high adhesion reliability and folding reliability in flexible display devices
Solution Approach 2:
The patent uses composite materials by formulating an adhesive resin composition containing multiple components: (meth)acrylate monomers, urethane (meth)acrylate oligomers, and photoinitiators. This composite formulation synergistically achieves the target Tg range, high peel force, and excellent deformation recovery properties across varying temperatures
2Strength
If the adhesive resin has high peel force, then adhesion strength is improved, but the deformation recovery rate may be compromised
Solution Approach 1:
The patent optimizes the chemical composition parameters of the adhesive resin to achieve a balance between peel force and deformation recovery. By adjusting the molecular weight and structure of urethane (meth)acrylate oligomers and selecting appropriate (meth)acrylate monomers, the adhesive achieves both high strength (≥800 gf/25mm at 25°C) and excellent elasticity (75-100% recovery)
Solution Approach 2:
The patent applies local quality by designing the adhesive resin with specific functional groups and molecular structures in different regions of the polymer chain. The urethane (meth)acrylate oligomers provide strong bonding sites for high peel force, while the flexible backbone structures provide elasticity for deformation recovery, achieving both properties simultaneously
3Temperature
If the glass transition temperature is lowered to improve low-temperature flexibility, then the adhesive remains flexible at low temperatures, but the high-temperature stability may be reduced
Solution Approach 1:
The patent precisely controls the glass transition temperature parameter within the range of -70°C to -30°C through optimization of the resin composition. This Tg range ensures the adhesive remains above its Tg at low temperatures (maintaining flexibility and deformation recovery) while not being too close to operating temperatures (maintaining stability at high temperatures)
Solution Approach 2:
The patent applies beforehand cushioning by selecting photoinitiators and additives that prevent degradation and maintain composition stability over time and across temperature cycles. This pre-cushioning approach ensures the adhesive maintains its programmed Tg and mechanical properties throughout the device's operational lifetime
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 adhesive member exhibits high adhesion reliability and folding reliability across low-temperature and high-temperature environments, maintaining durability and preventing lift-off or peeling, thus enhancing the overall performance of flexible display devices.
Implementation Method 1
a polymer derived from a resin composition including at least one (meth)acrylate monomer, at least one urethane (meth)acrylate oligomer, and at least one photoinitiator
Data Source
AI summary
An adhesive member includes a polymer derived from a resin composition. The resin composition includes at least one (meth)acrylate monomer, at least one urethane (meth)acrylate oligomer, and at least one photoinitiator. The adhesive member has a glass transition temperature in a range of about −70° C. to about −30° C., a 180° peel force of about 800 gf/25 mm or greater at a temperature of 25° C., and a deformation recovery rate in a range of about 75% to about 100% at temperatures of −20° C. and 60° C. The deformation recovery rate satisfies the following equation: X2=[1−(X1/25)]×100%, where X1 denotes a shear strain measured 600 seconds after removing a shear stress applied in a way such that the adhesive member has a shear strain of 25% at the temperatures of −20° C. and 60° C., and X2 denotes the deformation recovery rate.