1. Home
  2. Products
  3. LED Optics Silicone Rubber
  4. High Refractive Index Silicone (for SMD LED Encapsulation)

High Refractive Index Silicone for SMD LED Encapsulation

Model No.

Product Features
High refractive index
High optical transparency
Low air and water permeability
Excellent resistance to heat, cold and UV
Perfect adhesion to substrates such as metal, PPA, ceramics, etc.

Main Applications
The high refractive index silicone is ideal for encapsulation of SMD LEDs.

Typical Properties
Before curing Physical properties SR2530A SR2530B
Appearance Colorless and transparent Colorless and transparent
Refractive index( 25°C ) 1.54 1.54
Density (g/ cm) 1.15 1.15
Viscosity( 25°C )mPa·s 12000 2500
Mixing ratio 1 2
Viscosity after mixing( 25°C )mPa·s 5000
Operable time( 25°C ) 8 hours
After curing SHORE hardness 50
Refractive index( 25°C ) 1.54
Tensile strength ( Mpa ) 2.8
Elongation (%) 0.6
Light transmittance (450 nm, 1 mm) 0.94
Glass transition temperature( Tg , ℃ ) 12.5
Coefficient of linear expansion( α1 ) 70ppm
Coefficient of linear expansion( α2 ) 220ppm
Shrinkage after curing about 3%

1) Curing condition is recommended to be first cure 100℃ x1 hours + post cure 150℃ x3hours
2) The encapsulation silicone should be stored at room temperature in an indoor dry and ventilated place without direct sunlight. Shelf life of this encapsulation material is 12 month.
3) Viscosity is measured by NDJ-79 rotary viscosimeter.
4) Above table is only for reference use. Contact us detailed molding process.

Related products