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EPO-TEK® 305 Spectrally Transparent Flexible Epoxy, Room Temperature Cure (4g)
ET305-4G
Features:
- Transmits light in the UV range
- Semi-flexible/semi-rigid with Tg and Shore D values suitable for low-stress optical applications
- Low-viscosity, water-like consistency for pouring, dip coating, brushing, or micro-dispensing
- Versatile curing: 23°C–80°C(73.4–176°F), compatible with many low-cost plastics
- Pot life: 1 Hour
Applications:
- Optics:
- Index-matching adhesive or coating for scientific and OEM instruments
- LED potting and encapsulation
- LCD glass-glass or glass-PET laminations
- Fiber Optics: Potting or sealing fibers in opto-packages to relieve stress
- PCB / General Electronics: Low-stress potting or COB glob top encapsulant as a clear coating
Physical Properties:
- Consistency: Pourable liquid
- Viscosity (23°C): ≤ 250 cPs
- Glass Transition Temperature, Tg: ≥ 35°C (degree Celsius); ≥ 95°F (degree Fahrenheit)
- Shore D Hardness: 66
- Coefficient of Thermal Expansion (CTE):
- Below Tg: 31 x 10-6 in/in°C
- Above Tg: 148 x 10-6 in/in°C
- Suggested Operating Temperature: < 200 °C (Intermittent); < 392°F
Optical Properties @ 23°C (73.4°F):
- Spectral Transmission:
- > 67% @ 260 nm
- > 95% @ 340 nm
- > 98% @ 400 - 1600 nm
- Refractive Index: 1.4763 @589 nm
See Datasheet for additional properties and application notes
Datasheet
SDS (Part A)
SDS (Part B)
Mixing Instructions
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