Flexible Display Insulating Layer with Low Modulus Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing flexible image display media with a dielectric film inside the substrate face issues with substrate damage and charge leakage due to particle collisions, leading to degradation, and excessive film thickness causes peeling during bending deformation.
Innovation Solution
An image display medium with a first substrate, a second substrate, and an insulating layer bonded by a first bonding layer with a Young's modulus lower than the substrate, ensuring sufficient insulating properties and flexibility to prevent peeling during bending, along with a coat layer to protect electrodes and reduce residual stress.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the dielectric film thickness is increased to suppress substrate damage and charge leakage from particle collisions, then the insulating property is improved, but the film cannot follow bending deformation, causing peeling to occur
Solution Approach 1:
The dielectric film is divided into multiple thin layers (first dielectric layer, second dielectric layer, third dielectric layer) rather than using a single thick layer. This segmentation allows each thin layer to flexibly follow substrate bending while collectively providing sufficient insulating thickness, preventing peeling during deformation
Solution Approach 2:
The patent uses composite dielectric layers with different materials (inorganic insulating films like SiO2, SiN, SiON combined with organic insulating films) to achieve both high insulating properties and flexibility. The composite structure provides optimal balance between thickness requirements for insulation and flexibility requirements for bending resistance
2Reliability
If the dielectric film thickness is increased to prevent charge leakage, then the insulating property is improved, but the space volume increases, causing particle flocculation to occur easily
Solution Approach 1:
The patent applies different dielectric layers with different properties at different locations and positions. The first dielectric layer near the substrate provides mechanical adhesion and flexibility, while subsequent layers provide insulating properties. This local differentiation allows optimal charge retention without excessive overall thickness that would cause particle flocculation
3Reliability
If a coat layer is added to protect electrodes and reduce residual stress, then the electrode protection is improved, but the device complexity increases
Solution Approach 1:
The coat layer serves multiple functions simultaneously: it protects the transparent electrode from damage, reduces residual stress in the film stack to prevent warpage, and provides a surface for subsequent layer adhesion. This multi-functionality justifies the additional layer by delivering multiple benefits from a single structural addition
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 peeling and maintains insulating properties during bending, suppressing pinhole formation and charge leakage, while ensuring adequate electric field strength and preventing display failures due to excessive adhesive force.
Implementation Method 1
an insulating layer fixed to the at least one of the first substrate and the second substrate by the first bonding layer
Implementation Method 2
To use a composite polymer with inorganic particles dispersed as the coat layer, the residual stress of the coat layer is suppressed, whereby warpage of plastic film can be prevented
Implementation Method 3
the insulating layer has a thickness of 300 nm or more... If the insulating layer has a thickness to secure a sufficient insulating property
Implementation Method 4
the first bonding layer has a Young's modulus smaller than the substrate formed with the insulating layer and the insulating layer... when bending deformation of the image display medium is performed, etc., it becomes impossible to follow the deformation, causing peeling to occur
Data Source
AI summary
An image display medium includes: a first substrate; a second substrate facing the first substrate; a first bonding layer provided inside at least one of the first substrate and the second substrate; and an insulating layer fixed to the at least one of the first substrate and the second substrate by the first bonding layer, wherein the first bonding layer has a Young's modulus smaller than the substrate formed with the insulating layer and the insulating layer.