Radiation-Cured Adhesive for Electronic Encapsulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing adhesives for encapsulating (opto)electronic arrangements are inadequate in providing a strong barrier against oxygen and water vapor, leading to degradation of sensitive components like organic light-emitting diodes and solar cells, and they often require complex application processes and high temperatures, which can damage the electronic structures.
Innovation Solution
A pressure-sensitive adhesive composition comprising copolymers with isobutylene or butylene, hydrogenated adhesive resins, and reactive acrylate or methacrylate resins, which can be crosslinked via radiation, offering a balance of low permeability, high adhesion, and flexibility, allowing for easy and clean processing without the need for high temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional adhesives are used for encapsulation, then the structure is sealed, but the barrier against oxygen and water vapor is insufficient, leading to component degradation
Solution Approach 1:
The patent employs a multi-layer composite adhesive structure consisting of a first adhesive layer and a second adhesive layer with different formulations. The first layer provides initial adhesion and sealing, while the second layer enhances barrier properties against oxygen and water vapor. This composite approach allows the encapsulation to simultaneously achieve strong adhesion and superior protection against harmful permeants, directly resolving the contradiction between sealing capability and barrier performance.
2Strength
If high temperatures are used for adhesive application, then adhesion is improved, but the electronic structures are damaged
Solution Approach 1:
The patent utilizes pressure-sensitive adhesive technology that operates at ambient or low temperatures, fundamentally changing the application temperature parameter from conventional high-temperature curing processes. The adhesive composition is specifically formulated to achieve optimal adhesion strength without requiring thermal activation, thereby protecting temperature-sensitive electronic structures while still providing strong bonding between encapsulation layers.
3Reliability
If complex application processes are used, then adhesive performance is optimized, but manufacturing complexity increases
Solution Approach 1:
The patent divides the encapsulation structure into multiple adhesive layers, each with specific functions. The first adhesive layer provides primary bonding and sealing, while the second layer enhances barrier properties. This segmentation allows each layer to be optimized for its specific purpose while maintaining a relatively simple overall application process, as the layers can be applied in sequence using standard manufacturing techniques without requiring complex integrated processes.
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 adhesive provides a robust barrier against oxygen and water vapor, ensuring the longevity of (opto)electronic components while allowing for flexible and transparent encapsulation with improved processing ease and reduced risk of damage during application.
Implementation Method 1
at least one type of photoinitiator for initiating free-radical curing
Implementation Method 2
offering a balance of low permeability, high adhesion, and flexibility
Data Source
Figure 1~2
Figure 3~4
AI summary
The invention relates to an adhesive substance, in particular for encapsulating an electronic assembly against permeates, said substance comprising: (a) at least one copolymer containing at least isobutene or butene as comonomer types and at least one comonomer type which, when regarded as a hypothetical homopolymer, has a softening temperature greater than 40°C; (b) at least one type of an at least partially hydrogenated adhesive resin; (c) at least one acrylate- or methacrylate-based type of reactive resin with a softening temperature less than 40 °C, preferably less than 20°C; and (d) at least one type of photoinitiator for initiating radical curing.