Releasable Adhesive for Recyclable Circuit Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional printed circuit boards are difficult to disassemble and recycle, leading to waste and pollution, as they are typically incinerated or sent to landfills, with existing methods for reuse and recycling being inefficient and impractical.
Innovation Solution
The use of releasable adhesives in electronic circuit assemblies that can be separated under specific conditions, such as heating or exposure to water, allowing for the disassembly and recovery of components for recycling or reuse, with electrically conductive and non-conductive adhesives used to provide structural and electrical connections.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional soldering techniques are used to attach components to substrates, then strong mechanical and electrical connections are achieved, but the assembly becomes difficult to disassemble and recycle
Solution Approach 1:
The adhesive's bonding properties are changed based on environmental parameters - it maintains strong adhesion at normal operating temperatures but releases components when exposed to elevated temperatures or specific solvents, enabling both strong connection and easy disassembly
Solution Approach 2:
The adhesive transitions from a static permanent bond to a dynamic conditional bond, where the bonding strength can be modulated by external conditions such as temperature or chemical exposure, allowing the connection to be strong during operation but reversible during recycling
2Ease of manufacture
If traditional printed circuit boards are disposed of by incineration or landfill, then disposal is simplified, but material waste and pollution increase
Solution Approach 1:
The circuit assembly is designed as separable segments - components can be easily separated from the substrate using the releasable adhesive, allowing each component and material type to be recovered and reused independently rather than being disposed of as a single waste stream
Solution Approach 2:
The invention enables recovery of valuable components and materials from the circuit board by using adhesives that can be selectively released, allowing components to be recovered for reuse while the substrate and adhesive can be recycled, transforming the disposal process into a recovery process
3Ease of operation
If releasable adhesives are used to attach components to substrates, then disassembly and recycling become easy, but connection strength may be reduced
Solution Approach 1:
The adhesive is engineered to exhibit different bonding strengths under different parameter conditions - strong bonding at operating temperatures and weak bonding at release conditions (elevated temperature or solvent exposure), thus achieving both strong connection and easy disassembly
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 approach enables high percentage recovery and recyclability of electronic circuit components, exceeding 90%, by allowing for easy separation of components from the substrate without damaging the circuit, which is not possible with soldered components.
Implementation Method 1
the adhesive is releasable under certain release conditions, to allow for separation of the components and the substrate. The release conditions may require heating to a specific temperature, e.g. above 80° C., 80° C. to 100° C., or above 100° C.
Implementation Method 2
exposure to water or another solvent. These conditions may also be applied in combination, e.g. the adhesive may release on immersion in hot water.
Data Source
AI summary
An electronic circuit assembly comprises a substrate and circuit components attached to the substrate by means of an electrically conductive adhesive, wherein the adhesive is releasable under predetermined release conditions, whereby to enable the circuit components to be removed from the substrate for recovery or re-use.