Cover Insulating Layer Trenches for Air Bubble Discharge in Display Bonding

Solution Overview

Problem

The outer cover insulating layer in display devices prevents air bubbles generated by the anisotropic conductive film from being discharged, leading to unstable connecting processes and potential ripping of signal lines.

Innovation Solution

Incorporating a trench in the outer cover insulating layer that extends longitudinally and penetrates vertically, allowing air bubbles to be discharged outside the display panel, and ensuring the trench's bottom surface is lower than the anisotropic conductive film, thereby preventing signal line damage and stabilizing the connection process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the outer cover insulating layer is located in the edge area to cover the signal lines, then the signal lines are protected from being ripped, but air bubbles generated by the anisotropic conductive film cannot be discharged to the outside

Engineering Contradiction:

Improvesignal line protectionVSAvoidconnecting process stability

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The outer cover insulating layer is segmented by forming trenches that divide it into multiple regions. These trenches create pathways through the insulating layer, allowing air bubbles to escape while the remaining portions of the insulating layer continue to protect the signal lines. This segmentation resolves the contradiction by simultaneously enabling bubble discharge and maintaining signal line protection.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The outer cover insulating layer is designed with non-uniform structure: areas without trenches maintain full coverage to protect signal lines, while trench regions provide localized openings for air bubble discharge. This local quality variation allows different functions (protection and discharge) to coexist within the same insulating layer structure.

Inventive Principle:

Principle #3Local quality

2Strength

If the outer cover insulating layer completely covers the signal lines in the edge area, then the signal lines are protected from damage, but the connecting process becomes unstable due to trapped air bubbles

Engineering Contradiction:

Improvesignal line protectionVSAvoidconnecting process stability

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The outer cover insulating layer is segmented by forming trenches that divide it into multiple regions. These trenches create pathways through the insulating layer, allowing air bubbles to escape while the remaining portions of the insulating layer continue to protect the signal lines. This segmentation resolves the contradiction by simultaneously enabling bubble discharge and maintaining signal line protection.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The trenches act as intermediary structures that facilitate air bubble discharge without completely removing the protective function of the insulating layer. The trenches provide a controlled pathway for bubbles to escape, serving as a mediator between the protective insulating layer and the bonding process requirements.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Device complexity

If the outer cover insulating layer is formed without trenches, then the structure is simple and signal lines are fully covered, but air bubbles cannot be discharged leading to manufacturing defects

Engineering Contradiction:

Improveinsulating layer structureVSAvoidbonding area quality

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The outer cover insulating layer is segmented by forming trenches that divide it into multiple regions. These trenches create pathways through the insulating layer, allowing air bubbles to escape while the remaining portions of the insulating layer continue to protect the signal lines. This segmentation resolves the contradiction by simultaneously enabling bubble discharge and maintaining signal line protection.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The outer cover insulating layer is designed with a porous structure containing trenches that allow air bubbles to pass through. This porous design enables the insulating layer to perform its protective function while simultaneously providing escape routes for air bubbles, improving bonding area quality without requiring complete removal of the insulating layer.

Inventive Principle:

Principle #31Porous materials

Data Source

PatentUS9997588B2Display device having signal line extending to non-display area

Publication Date: 2018.06.12 LG DISPLAY CO LTD

AI summary

A display device according to an embodiment includes a display panel and a circuit board connected to the display panel. The circuit board is connected to a bonding area of the display panel by an anisotropic conductive film. The display panel includes a cover insulating layer exposing the bonding area. The cover insulating layer includes at least one trench crossing an edge area, which is located outside the bonding area.