Silicone-Epoxy Resin Composition for LED Encapsulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional encapsulating resins for semiconductor devices, such as LEDs, suffer from deterioration in mechanical strength, color irregularity, and yellowing under prolonged use and high temperatures, especially when exposed to high-energy light, leading to reliability issues.
Innovation Solution
A heat-curable silicone resin-epoxy resin composition combining a heat-curable silicone resin, a triazine derivative epoxy resin, an acid anhydride, and an inorganic filler, with a specific mass ratio and reaction conditions, to produce a cured product with enhanced heat resistance, light resistance, and minimal yellowing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional PPA resin is used for encapsulating high-energy light-emitting semiconductor devices, then good initial mechanical strength and encapsulation performance are achieved, but marked deterioration occurs upon prolonged use resulting in color irregularity, peeling, and reduction in mechanical strength
Solution Approach 1:
The patent employs a composite resin system combining PPA resin with polyimide resin and epoxy resin. This composite formulation leverages the high strength and heat resistance of PPA while incorporating polyimide's superior light resistance and epoxy's adhesion properties, thereby preventing the deterioration, peeling, and color irregularity observed in conventional PPA alone
2Reliability
If PPA resin is used as encapsulating material for high-brightness LEDs, then good initial encapsulation is achieved, but discoloration occurs upon prolonged illumination
Solution Approach 1:
The patent combines PPA resin with polyimide resin which has superior resistance to UV and visible light. This composite structure protects the encapsulated LED from discoloration during prolonged illumination while maintaining the mechanical advantages of PPA, directly addressing the light resistance issue
3Reliability
If epoxy resin and curing agent are mixed uniformly at molecular level to create B-stage epoxy resin composition, then good curability is achieved, but yellowing occurs particularly when left to stand for long periods at high temperature
Solution Approach 1:
The patent controls the degree of curing reaction by adjusting the mixing ratio of epoxy resin to curing agent and the pre-reaction conditions to achieve B-stage curing. This partial curing state improves heat resistance while minimizing the yellowing that occurs with complete curing at high temperatures over long periods
Solution Approach 2:
The patent combines epoxy resin with PPA resin and polyimide resin in a composite formulation. This composite approach leverages the heat resistance of epoxy while the other resins provide stability that prevents yellowing during prolonged high-temperature storage
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 composition achieves improved strength, retention of heat and light resistance over time, and minimal yellowing, making it suitable for high-brightness LEDs and solar cells, with excellent adhesion and durability.
Implementation Method 1
heat-curable silicone resin-epoxy resin composition comprising: (A) a heat-curable silicone resin, (B) a triazine derivative epoxy resin
Implementation Method 2
the composition achieves improved strength, retention of heat and light resistance over time, and minimal yellowing
Data Source
AI summary
A heat-curable silicone resin-epoxy resin composition that is ideal as a premolded package for a high-brightness LED or solar cell. The composition contains (A) a heat-curable silicone resin, (B) a combination of a triazine derivative epoxy resin and an acid anhydride, or a prepolymer obtained by reaction of them, (C) an inorganic filler, and (D) a curing accelerator. The composition exhibits excellent curability, and yields a uniform cured product that displays excellent retention of heat resistance and light resistance over long periods of time, and suffers minimal yellowing.