In-Place Tack-Free Gasket for Electronic Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gasket technologies for electronic devices face challenges in assembly due to their tacky nature, which can damage components and complicate the assembly process, and often require high temperatures that are not tolerated by electronic device components, leading to ineffective sealing and repair difficulties.
Innovation Solution
A flexible, tack-free gasket is formed in situ on a substrate using a radiation polymerizable composition comprising urethane acrylate monomers, diluents, photoinitiators, wax, thixotropic agents, and adhesion promoters, which cures through actinic radiation, allowing for easy assembly and repair without adhering to adjacent surfaces.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a preformed gasket is used to seal between housing layers, then sealing effectiveness is improved, but assembly difficulty increases due to tight clearances and risk of gasket flattening
Solution Approach 1:
The gasket composition is applied to the housing layer surface before final assembly, allowing the gasket to be pre-positioned in the correct location. This preliminary action ensures proper gasket placement without the difficulty of maneuvering preformed gaskets through tight clearances during assembly.
Solution Approach 2:
The composition is applied in a liquid or paste form that can flow into tight clearances and conform to the housing layer surface, then cures in-place to form the sealed gasket. This fluid state during application eliminates the mechanical handling difficulties of solid preformed gaskets.
2Strength
If co-molding is used to connect gasket to panel, then connection strength is improved, but temperature tolerance worsens as electronic components cannot tolerate high molding temperatures
Solution Approach 1:
The mechanical co-molding process requiring high temperatures is replaced with a chemical curing process. The composition cures at room or elevated temperatures through chemical reaction (such as UV curing or two-part mixing) to form a strong bond between the gasket and panel without exposing electronic components to damaging high temperatures.
Solution Approach 2:
The curing temperature parameter is changed from high-temperature mechanical molding to lower-temperature chemical curing. This parameter change allows the gasket to achieve strong adhesion to the panel while maintaining compatibility with heat-sensitive electronic components.
3Reliability
If a gasket is formed with strong adhesion to prevent debris entry, then sealing reliability is improved, but repairability worsens as components cannot be easily detached
Solution Approach 1:
The gasket's adhesion properties are made dynamic through the curing process. Initially, the composition remains uncured and non-adhesive, allowing easy component placement and adjustment. After assembly, the composition cures to provide strong adhesion for sealing. For repairs, the cured gasket can be re-softened or the housing can be heated to reverse the curing and restore non-adhesive properties, enabling component removal.
Solution Approach 2:
The adhesion characteristic changes periodically through the curing process. The gasket transitions from non-adhesive (during assembly) to adhesive (during service) and can return to non-adhesive (during repair). This periodic change in adhesion state enables both strong sealing during use and easy disassembly for repairs.
4Stability of the object's composition
If high temperature curing is used to cure gasket material, then cure completeness is improved, but component damage risk increases for heat-sensitive electronic devices
Solution Approach 1:
Thermal curing is replaced with alternative curing mechanisms such as UV light curing, electron beam curing, or two-part chemical curing. These methods achieve complete curing of the gasket material without requiring high temperatures, thereby protecting heat-sensitive electronic components from thermal damage.
Solution Approach 2:
The curing method parameter is changed from thermal curing to non-thermal curing mechanisms. This parameter change maintains complete cure of the gasket composition while eliminating the harmful high temperatures that would damage electronic components.
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 flexible, tack-free gasket with Shore A hardness ranging from A20 to A80, enabling easy assembly and repair of electronic devices by preventing debris entry and allowing for non-adhesive detachment of components, thus enhancing the durability and maintainability of electronic devices.
Implementation Method 1
exposing the liquid composition to sufficient actinic radiation to thereby cure the liquid composition into a flexible, substantially tack free gasket
Implementation Method 2
from 2 wt% to 10 wt. % of a thixotropic agent
Data Source
Figure 1
AI summary
A method of preparing a flexible, substantially tack free gasket by forming a liquid composition which is a radiation polymerizable admixture of a free radical polymerizable urethane (meth)acrylate monomer, free radical polymerizable urethane (meth)acrylate oligomer, or combinations thereof; a free radical polymerizable diluent; a free radical polymerization photoinitiator; a wax; a thixotropic agent; and optionally an adhesion promoter and a colorant. The composition is distributed onto a substrate and then exposed to actinic radiation to cure the liquid composition into a flexible, substantially tack free gasket having a Shore A hardness of from about A20 to about A80.