Low-Temperature Curable Epoxy Adhesive for Heat-Sensitive Substrates
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional thermosetting adhesive materials are ineffective for bonding elements with low thermal resistance materials, as they deform or decompose at elevated temperatures, necessitating a curable composition that exhibits adhesiveness without high-temperature heating.
Innovation Solution
A curable composition containing an epoxy resin with a specific structural unit, applied to adherends with low heat-resistance materials, is heated between 80°C and 100°C and exposed to cure, forming a bonding layer with a water contact angle of 40° to 50°, ensuring adhesiveness without thermal degradation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional thermosetting adhesive materials are used for bonding, then strong bonding strength is achieved, but the adherends undergo thermal deformation and decomposition at elevated temperatures
Solution Approach 1:
The patent changes the curing temperature parameter from conventional high temperatures (200°C or higher) to a lower temperature range (80°C to 100°C). This is achieved by using an epoxy resin with a specific structural unit (formula g1-1) that enables curing at lower temperatures while still achieving favorable adhesiveness, thus preventing thermal deformation and decomposition of heat-sensitive adherends
Solution Approach 2:
The patent uses a composite curable composition containing both the specific epoxy resin (with structural unit g1-1) and a photopolymerization initiator. This composite material system enables dual-curing capability where the epoxy resin provides low-temperature curing and the photopolymerization initiator enables UV exposure curing, combining the advantages of both curing methods to achieve strong bonding without high-temperature damage
2Object-affected harmful factors
If low curing temperature is used to protect heat-sensitive materials, then thermal damage is prevented, but adhesiveness is reduced
Solution Approach 1:
The patent modifies the chemical structure of the epoxy resin by introducing a specific structural unit (formula g1-1) with particular molecular characteristics (mass average molecular weight of 1,000 to 50,000). This structural modification enables the resin to achieve adequate adhesiveness at lower curing temperatures (80°C to 100°C) without requiring high-temperature processing, thus resolving the contradiction between low temperature and adhesiveness
Solution Approach 2:
The patent introduces a photopolymerization initiator as an intermediary that enables UV exposure curing of the coating film. This intermediary substance allows the curable composition to cure effectively at low temperatures through photopolymerization, compensating for the reduced thermal energy available for curing and maintaining adhesiveness without causing thermal damage to the adherends
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 curable composition effectively bonds adherends with low heat-resistance materials, preventing thermal deformation and decomposition, while maintaining optical properties and achieving high adhesiveness and transparency.
Implementation Method 1
heating the coating film at 80° C. or higher and 100° C. or lower, and subsequently exposing the coating film, thereby curing the coating film
Implementation Method 2
subsequently exposing the coating film, thereby curing the coating film
Data Source
AI summary
Provided are a curable composition that exhibits favorable adhesiveness without heating at elevated temperatures, and a method for producing a joined structure using the curable composition. As a curable composition for use in forming one or more bonding layers bonding the two or more adherends, in which at least one of the two or more adherends includes a low heat-resistance material, a curable composition that contains an epoxy resin including a structural unit of a specific structure including an epoxy group, and yields a cured product exhibiting a water contact angle of 40° or more and 50° or less by heating at 80° C. or higher and 100° C. or lower and an exposure is used.