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Low Refractive Index Silicone for COB LED Encapsulation


Product Features
1. The low refractive index silicone comes with high toughness.
2. It provides excellent resistance to heat, cold and UV.
3. The organic silicone comes with superior adhesion to metal, PPA, ceramic and other substrates.

Main Applications
The low refractive index silicone is mainly used for encapsulation of COB LEDs.


Typical Properties
Before curing Physical properties SR2530A SR2530B
Appearance Colorless and transparent Colorless and transparent
Refractive index(25°C) 1.41 1.41
Density (g/ cm) 1.03 1.03
Viscosity(25°C ) mPa·s 4500 3000
Mixing ratio 100 100
Viscosity after mixing(25°C ) mPa·s 4000
Operable time(25°C) 8h
After curing SHORE hardness 45
Refractive index(25°C) 1.41
Tensile strength ( Mpa ) 6
Elongation (%) 150%
Light transmittance (450 nm, 1 mm) 94%

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

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