Rollable Flexible Display Adhesive Structure for Sliding Durability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The durability of flexible displays in rollable electronic devices is compromised due to adhesive fatigue failure, either from using a high modulus adhesive that reduces fluidity or a low modulus adhesive that decreases durability, during sliding operations.
Innovation Solution
A flexible display with a first adhesive layer having a higher modulus for the visible portion and a second adhesive layer with a lower modulus for the bendable portion, enhancing durability and reducing adhesive fatigue.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a high modulus adhesive is used in the first adhesive portion to enhance durability, then the durability of the flexible display is improved, but the fluidity of the adhesive decreases during sliding operation
Solution Approach 1:
The adhesive layer is divided into two portions with different moduli: the first adhesive portion (corresponding to the first portion of the flexible display) uses a relatively rigid material with higher modulus to enhance durability, while the second adhesive portion (corresponding to the second portion) uses a softer material with lower modulus to maintain fluidity and accommodate slip during sliding operations. This local differentiation resolves the contradiction by optimizing each region's adhesive properties according to its specific functional requirements.
2Ease of operation
If a low modulus adhesive is used in the second adhesive portion to accommodate slip between layers, then the ease of operation is improved, but the strain increases leading to fatigue failure
Solution Approach 1:
The adhesive layer is divided into two portions with different moduli: the first adhesive portion (corresponding to the first portion of the flexible display) uses a relatively rigid material with higher modulus to enhance durability, while the second adhesive portion (corresponding to the second portion) uses a softer material with lower modulus to maintain fluidity and accommodate slip during sliding operations. This local differentiation resolves the contradiction by optimizing each region's adhesive properties according to its specific functional requirements.
3Device complexity
If a single adhesive layer is used, then the device complexity is reduced, but the durability during sliding operations deteriorates
Solution Approach 1:
The adhesive layer is segmented into two distinct portions with different material properties: the first adhesive portion with higher modulus for durability and the second adhesive portion with lower modulus for fluidity. This segmentation allows each portion to perform its specific function optimally, resolving the contradiction between structural simplicity and operational durability.
Data Source
AI summary
An electronic device is provided. The electronic device includes a first housing, a second housing configured to move with respect to the first housing, and a flexible display including a first display portion and a second display portion, wherein at least part of the second portion is drawn into or withdrawn from an internal space of the electronic device in accordance with the second housing moving with respect to the first housing, wherein the flexible display includes a first window layer, a second window layer disposed on the first window layer, and at least two adhesive layers including a first adhesive layer and a second adhesive layer, disposed between the first window layer and the second window layer, the at least two adhesive layers configured to adhesively attach the first window layer to the second window layer, wherein the first adhesive layer includes a first adhesive portion corresponding to the first display portion and a second adhesive portion corresponding to the second display portion, wherein a modulus of the second adhesive portion is lower than a modulus of the first adhesive portion, and a modulus of the second adhesive layer is equal to or lower than the modulus of the first adhesive portion.