Flexible Display Panel Viscoelastic Bonding Layer

Solution Overview

Problem

Flexible displays face challenges in achieving higher mechanical strength, particularly when used as touch panels, as they can be damaged by strong touches, and adding protective films increases thickness and reduces flexibility.

Innovation Solution

A display device configuration that includes a display panel with a first film, a second film, and a bonding layer between them, where the bonding layer has viscoelastic properties and higher stretchability than the films, allowing the display panel to maintain flexibility while enhancing mechanical strength.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a protective film is attached to the display surface to prevent damage, then mechanical strength is improved, but thickness increases and flexibility decreases

Engineering Contradiction:

Improvemechanical strengthVSAvoidthickness

Core Design Contradiction:

StrengthVSLength of moving object

Solution Approach 1:

The protective function is nested within the existing display panel structure by utilizing the bonding layer as a protective element. The bonding layer is positioned between the display element and the outer film, creating a nested protective structure that does not increase overall thickness while providing mechanical protection against damage

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The bonding layer serves as an intermediary element between the display element and the outer film. This intermediate layer absorbs and distributes stress from external touches, protecting the display element while maintaining the thin profile of the overall structure

Inventive Principle:

Principle #24Intermediary (Mediator)

2Strength

If a protective film is attached to the display surface to prevent damage, then mechanical strength is improved, but flexibility decreases

Engineering Contradiction:

Improvemechanical strengthVSAvoidflexibility

Core Design Contradiction:

StrengthVSAdaptability or versatility

Solution Approach 1:

The protective function is nested within the existing display panel structure by utilizing the bonding layer as a protective element. The bonding layer is positioned between the display element and the outer film, creating a nested protective structure that does not increase overall thickness while providing mechanical protection against damage

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The bonding layer serves as an intermediary element between the display element and the outer film. This intermediate layer absorbs and distributes stress from external touches, protecting the display element while maintaining the thin profile of the overall structure

Inventive Principle:

Principle #24Intermediary (Mediator)

3Adaptability or versatility

If the display panel is made thinner to improve flexibility, then flexibility is improved, but mechanical strength decreases

Engineering Contradiction:

ImproveflexibilityVSAvoidmechanical strength

Core Design Contradiction:

Adaptability or versatilityVSStrength

Solution Approach 1:

The display panel employs a composite structure consisting of multiple layers including the display element, bonding layer, and outer film. This composite construction allows the panel to maintain thinness for flexibility while the combined structure provides enhanced mechanical strength through the synergistic properties of different materials

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The bonding layer serves as an intermediary element between the display element and the outer film. This intermediate layer absorbs and distributes stress from external touches, protecting the display element while maintaining the thin profile of the overall structure

Inventive Principle:

Principle #24Intermediary (Mediator)

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 proposed solution enables flexible displays to withstand touches without damage, maintains thinness and flexibility, and improves the reliability of the display device by distributing stress effectively through the viscoelastic bonding layer.

Implementation Method 1

The first bonding layer has viscoelasticity and is higher in stretchability than the first film and the second film

Methodology Applied

Scientific EffectViscoelasticity: Viscoelasticity

Data Source

PatentUS20250204237A1Display device and electronic device

Publication Date: 2025.06.19 SEMICON ENERGY LAB CO LTD

AI summary

A flexible display is prevented from being damaged. A display device having thickness and flexibility both is provided. The display device includes a display panel with a display element. The display panel includes a first film, a second film, and a bonding layer. The bonding layer is positioned between the first film and the second film, and has a function of attaching the first film and the second film to each other. The display element is supported by the first film. The display panel has a bending modulus of elasticity being higher than or equal to 0.01 times a tensile modules of elasticity and lower than one times the tensile modulus of elasticity.