SEEPS Hot Melt Composition for Heat-Stable Adhesion and Disassembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hot melt adhesives used in automotive lighting appliances face challenges with deformation at high temperatures and poor disassembly properties, particularly in LED lighting applications, leading to difficulties in maintaining form and ease of removal during repairs.
Innovation Solution
A hot melt composition comprising a styrene-ethylene-ethylene/propylene-styrene block copolymer (SEEPS) and a hydrocarbon-based liquid softening agent with an aniline point of 135°C or more, along with optional components like a styrene-ethylene/propylene block copolymer (SEP), tackifier resin, and polycarbonate component, to enhance adhesion and ease of disassembly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a styrene-based block copolymer is used as a sealing agent, then adhesion to lighting appliance parts is improved, but deformation occurs at high temperatures
Solution Approach 1:
The patent uses a composite material system consisting of styrene-based block copolymer (SEEPS or SEPS) combined with specific hydrocarbon-based liquid softening agents (having aniline point of 120°C or more) and tackifier resins. This composite approach allows the adhesive to simultaneously achieve strong adhesion to lighting appliance parts and maintain form stability at high temperatures, resolving the contradiction between adhesion strength and heat resistance.
2Reliability
If moisture-curable hot melt adhesives are used for sealing, then sealing property is improved, but disassembly becomes difficult
Solution Approach 1:
The patent employs parameter changes by selecting specific hydrocarbon-based liquid softening agents with aniline points of 120°C or more (such as paraffinic oil with aniline point of 135-150°C). This parameter selection allows the adhesive to maintain reliable sealing properties during use while enabling easy disassembly when needed, as the specific oil composition prevents excessive curing and maintains reversibility of the bonding.
3Reliability
If adhesive strength increases with time, then sealing reliability is improved, but disassembly property deteriorates
Solution Approach 1:
The patent uses parameter changes by carefully selecting hydrocarbon-based liquid softening agents with specific aniline points (120°C or more) and combining them with tackifier resins having specific softening points. This parameter optimization ensures that the adhesive maintains consistent sealing reliability over time without excessive strength increase that would prevent disassembly, achieving both long-term reliability and repairability.
Data Source
AI summary
An objective of the present invention is to provide a hot melt composition having a high form maintaining property at a high temperature and being in excellent adhesion to a substrate and in disassembly. The present invention relates to a hot melt composition comprising: (A1) a styrene-ethylene-ethylene/propylene-styrene block copolymer (SEEPS) and (B1) a hydrocarbon-based oil having an aniline point of 135° C. or more.