Resin Composition for Image Display Device Warping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional liquid crystal display devices with a gap between the image display panel and the protective part suffer from light scattering, reduced contrast and brightness, and image defects due to internal stress from resin curing shrinkage and external stress from temperature-induced warping of the protective part.
Innovation Solution
A cured resin with adjusted elongation ratio and adhesive strength is used between the image display part and the protective part, allowing it to follow warping while minimizing internal stress and peeling, and its refractive index is matched to the surrounding panels to reduce light reflection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a resin is used to fill the gap between the liquid crystal display panel and the protective part, then light scattering is reduced and contrast is improved, but internal stress from curing shrinkage causes deformation and image defects
Solution Approach 1:
The patent modifies the chemical composition parameters of the resin, specifically incorporating flexible chain components and adjusting the ratio of rigid to flexible segments. This changes the physical properties of the cured resin to reduce curing shrinkage and internal stress, thereby preventing deformation and image defects while maintaining high contrast performance
Solution Approach 2:
The patent creates a composite resin system combining multiple components including polyisoprene polymer with maleic anhydride adduct, 2-hydroxyethyl methacrylate, hydrogenated terpene resin, butadiene polymer, and specific photopolymerization initiators. This composite formulation achieves both high light transmittance for contrast and controlled shrinkage for image uniformity
2Length of moving object
If the protective part is made thinner to reduce device thickness, then device thickness is reduced, but warping due to temperature fluctuations increases causing image defects
Solution Approach 1:
The resin composition is designed with specific molecular weight parameters and flexibility ratios that enable it to accommodate thermal expansion and contraction of thin protective parts. The flexible chain components allow the resin to follow warping without generating excessive stress, maintaining adhesion and preventing image defects even when the protective part is made thinner
Solution Approach 2:
The patent incorporates stress-absorbing flexible components in advance within the resin formulation, creating a buffer capacity that prevents stress concentration during thermal cycling. This beforehand cushioning allows the resin to absorb warping stresses before they can cause peeling or image defects
3Length of moving object
If a plastic plate is used as the protective part to reduce thickness, then device thickness is reduced, but the cured resin cannot follow warping and peeling occurs
Solution Approach 1:
The patent adjusts the flexibility parameters of the resin by incorporating specific ratios of polyisoprene polymer and butadiene polymer, which provide elastic recovery and followability. This allows the cured resin to dynamically follow the warping of plastic protective parts without losing adhesion, preventing peeling while enabling thin device design
Solution Approach 2:
The resin formulation effectively creates a flexible bonding layer that can deform with the protective part. The molecular structure includes flexible chains that provide the necessary compliance to match the warping behavior of thin plastic protective parts, maintaining continuous adhesion under thermal stress
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 results in a high-brightness, high-contrast display with reduced image defects and improved durability against shocks, maintaining in-plane uniformity and preventing peeling, while enabling a thinner display device.
Implementation Method 1
a cured resin formed by filling a resin composition in a gap between an image display part and a protective part and then curing
Data Source
Figure 1~2
Figure 3~4
AI summary
An image display device has an image display part and a protective part on the image display part. The image display device suppresses image unevenness and cured resin peeling caused by internal stress generated due to curing shrinkage of a cured resin between the protective part and the image display part or external stress applied on the image display part due to warping of the protective part. A cured resin layer is arranged between the image display part and the protective part. The cured resin layer has a light transmittance in the visible region of 90% or more, an elongation ratio of 700% or more at 25°C and 400% or more at 80°C, and an adhesive force with respect to the protective part of 0.4 N/cm or more at 25°C and 0.3 N/cm or more at 80°C.