| 초록 |
As lighting device, LED packaged on a reflector cup with wires and heat sinks, which is then encased in an encapsulant containing phosphors. Among these components, the encapsulant plays critical roles in providing physical protection, long-term reliability, and light extraction efficiency of LED. For curing of conventional silicone LED encapsulant, a platinum-derived addition curing, hydrosilylation, is used due to its high clarity. However, the LED encapsulant cured by hydrosilylation leads to low adhesion to LED chip as well as low cost compatibility. Herein, we report a platinum-free LED encapsulant using radical curing of sol-gel derived vinyl-phenyl oligosiloxane exhibiting extremely high refractive index (n=1.588). The LED encapsulant shows compatible transparency and thermal resistance to yellowing with platinum-cured LED encapsulant. Furthermore, the LED encapsulant higher adhesion than platinum-cured LED encapsulant. |
