Reactive Pressure-Sensitive Adhesive Element for Electronics Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing double-sided reactive pressure-sensitive adhesive elements lack pressure-sensitive adhesiveness, making it difficult to position and remove them accurately, and they do not facilitate easy recycling due to strong bond durability, which hinders ecological and economic recycling efforts.
Innovation Solution
A reactive pressure-sensitive adhesive element with a carrier layer comprising a polyolefin foam, featuring UV-curable pressure-sensitive adhesive layers with poly(meth)acrylate and epoxy compounds, allowing for pressure-sensitive adhesiveness, efficient curing, and easy separation after bonding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If reactive adhesive tapes are used to achieve strong bond durability, then bond strength is improved, but ease of removal and recycling deteriorates
Solution Approach 1:
The adhesive element provides dynamically different bonding behaviors: before UV curing it exhibits pressure-sensitive adhesiveness allowing easy positioning and removal, while after curing it forms strong permanent bonds. This temporal dynamic property resolution allows the same adhesive to satisfy both ease of removal during processing and strong bonding during use.
Solution Approach 2:
The adhesive's bonding parameters change fundamentally through UV irradiation. Before curing, the adhesive remains in a soft, repositionable state with low bond strength. Upon UV exposure, the adhesive undergoes polymerization transforming into a crosslinked network with high bond strength and reduced removability, thus resolving the contradiction between ease of removal and bond strength through parameter transformation.
2Reliability
If reactive adhesive tapes are used to achieve strong bond durability, then reliability is improved, but recyclability deteriorates
Solution Approach 1:
The adhesive exhibits periodic functional states: an uncured state suitable for application and removal, and a cured state providing reliable bonding. The UV curing process acts as a periodic trigger that transitions the adhesive between these states, enabling reliable bonding during the product lifecycle while allowing for potential recycling through controlled uncuring or separation processes.
3Ease of operation
If pressure-sensitive adhesive characteristics are added to reactive adhesive tapes, then ease of operation is improved, but device complexity deteriorates
Solution Approach 1:
The invention merges two previously separate adhesive functionalities into a single integrated adhesive composition: pressure-sensitive adhesiveness for easy handling and UV-curable reactive bonding for strong adhesion. This consolidation into one multi-functional adhesive layer simplifies the overall device structure compared to using separate adhesive layers or systems.
Solution Approach 2:
The adhesive composition achieves multi-functionality by simultaneously providing pressure-sensitive adhesiveness for easy positioning and removal, and UV-curable reactive bonding for strong permanent adhesion. This universal adhesive satisfies multiple functional requirements that would traditionally require different adhesive systems, thereby reducing overall system complexity.
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 solution provides a pressure-sensitive adhesive element that is easily removable before curing, achieves strong and durable bonds, and enables efficient separation for recycling, suitable for the electronics industry, particularly for bonding displays in housings.
Implementation Method 1
Appropriate curable adhesives have not yet reached their maximum degree of crosslinking in the state intended for application and can be cured by external influences by initiating the polymerization in the curable adhesive and thereby increasing the degree of crosslinking
Implementation Method 2
pressure-sensitive adhesive ensures the adhesive effect, which is permanently sticky and adhesive under normal ambient conditions
Data Source
AI summary
A reactive pressure-sensitive adhesive element that includes: i) a carrier layer; ii) a first adhesive layer arranged on a first surface of the carrier layer that comprises a first UV-curable pressure-sensitive adhesive; and iii) a second adhesive layer arranged on a second surface of the carrier layer facing away from the first surface, wherein the second adhesive layer comprises a second UV-curable pressure-sensitive adhesive. Each of the first and second UV-curable pressure-sensitive adhesives, based on a mass of the respective pressure-sensitive adhesive, comprises: x) one or more poly (meth) acrylate compounds in a combined mass fraction from 35% to 85%; y) one or more polymerizable epoxy compounds in a combined mass fraction from 10% to 50%; and z) one or more photoinitiators in a combined mass fraction from 0.1% to 5%. Further, the carrier layer comprises a foam carrier, the foam carrier comprising one or more polyolefins.