Azo Photosensitive Layer for Non-Destructive Flexible Display Substrate Separation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current methods for separating flexible substrates from carrier substrates in flexible OLED display technology often damage the display device due to high temperatures or chemical corrosion, shortening its lifespan.

Innovation Solution

A method involving the formation of a photosensitive layer with an azo group on a carrier substrate, which changes from a trans to a cis state under ultraviolet light, reducing adhesion and allowing for non-destructive peeling of the flexible substrate without damaging the display device, using mechanical or physical adsorption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If laser stripping or resistance heating stripping is used to remove the carrier substrate, then the flexible substrate can be separated from the carrier substrate, but high temperatures are generated which may damage the display device

Engineering Contradiction:

Improveseparation of flexible substrate from carrier substrateVSAvoiddamage to display device due to high temperature

Core Design Contradiction:

Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The patent replaces thermal separation methods (laser stripping, resistance heating) with a photochemical method. A photosensitive layer containing azo groups is applied to the carrier substrate, and upon UV irradiation, the azo groups undergo trans-cis isomerization that reduces adhesion between the flexible substrate and carrier substrate, enabling separation at room temperature without thermal damage to the display device.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the chemical state of the photosensitive layer by irradiating it with ultraviolet light, causing the azo groups to transition from trans state to cis state. This parameter change in molecular configuration reduces the adhesion strength of the photosensitive layer, allowing the flexible substrate to be peeled off from the carrier substrate without high temperature damage.

Inventive Principle:

Principle #35Parameter changes

2Ease of manufacture

If chemical separation methods are used to separate the flexible substrate from the carrier substrate, then the flexible substrate can be removed, but the display device is corroded which shortens its lifespan

Engineering Contradiction:

Improveseparation of flexible substrate from carrier substrateVSAvoidlifespan of display device due to corrosion

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent replaces chemical separation methods that cause corrosion with a photochemical isomerization method. The azo-containing photosensitive layer undergoes trans-cis isomerization upon UV irradiation, reducing adhesion through molecular configuration change rather than chemical corrosion, thereby preserving the display device and extending its lifespan.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Ease of manufacture

If traditional separation methods are used, then the flexible substrate can be separated from the carrier substrate, but residual glue remains which affects display quality

Engineering Contradiction:

Improveseparation of flexible substrate from carrier substrateVSAvoiddisplay quality affected by residual glue

Core Design Contradiction:

Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent extracts the photosensitive layer's adhesive function into a separate, removable component. The azo-containing photosensitive layer is designed to be completely removable upon UV irradiation, taking the adhesive function with it when peeled off, thereby leaving no residual glue on the flexible substrate that would affect display quality.

Inventive Principle:

Principle #2Taking out (Extraction)

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

This method enables efficient, non-destructive separation of the flexible substrate from the carrier substrate, preventing damage to the display device and ensuring a longer lifespan, while also avoiding residual glue issues and improving peeling efficiency.

Implementation Method 1

a photosensitive layer comprising at least one azo group on a carrier substrate; forming a flexible substrate on the photosensitive layer; irradiating the photosensitive layer with ultraviolet light

Methodology Applied

Scientific EffectPhotoisomerization: Photochromism

Data Source

PatentUS11309528B2Flexible display panel and fabricating method thereof, flexible display apparatus

Publication Date: 2022.04.19 BOE TECHNOLOGY GROUP CO LTD

AI summary

The present disclosure relates to a method of fabricating a flexible display panel. The method of fabricating the flexible display panel may include forming a photosensitive layer comprising at least one azo group on a carrier substrate; forming a flexible substrate on the photosensitive layer; irradiating the photosensitive layer with ultraviolet light; and peeling off the flexible substrate from the carrier substrate.