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EPO-TEK® 302-3M Optically Opaque Black Epoxy, Room Temperature Cure (2.5g)
ET302-3MBLK2.5G
EPO-TEK® 302-3M Black General Bonding & Fiber Optic Epoxy, Room Temperature Cure, 2-Part Epoxy, 2.5 Gram Packet
The EPO-TEK® 302-3M Optically Opaque Black Epoxy is a two-component room temperature curing epoxy used for optical, fiber optic, and semiconductor applications. The system offers excellent joining, sealing, potting, and coating. Recommended Cure: 65°C(149°F) for 3 Hours. Available in a 2.5-gram packet.
See Datasheet for additional properties and application notes
Features:
- Low-viscosity, black epoxy ideal for potting and light-blocking in optoelectronics
- Excellent resistance to water, chemicals, and solvents, including 10% nitric acid, acetone, hexane, and dichloromethane
- Pot Life: 1 hour
- Suitable for joining and encapsulating glass, quartz, stainless steel, Kovar, and ceramic components
Applications:
- Fiber Optic & Optical:
- Potting and encapsulation; light blocking and optics sealing applications
- Passive fiber sealing in opto-packages
- Adhesive for V-groove, fiber arrays or lens arrays
- Bonding optical fibers into ferrules (glass or plastic fibers; glass, quartz, stainless steel, kovar, or ceramic ferrules)
- Semiconductor:
- Underfill for flip chips or SMDs on PCB
- COB glob-top processes using DAM/FILL method
- Resistant to 85/85 moisture soaks, temperature cycling, and thermal shock
Physical Properties:
- Consistency: Pourable liquid
- Viscosity (23°C): 800-1,600 cPs
- Glass Transition Temperature (Tg): ≥ 55°C (degree Celsius); ≥ 131°F (degree Fahrenheit)
- Shore D Hardness: 80
- Coefficient of Thermal Expansion (CTE):
- Below Tg: 56 × 10⁻⁶ in/in °C
- Above Tg: 193 × 10⁻⁶ in/in °C
- Suggested Operating Temperature: < 250 °C (Intermittent); < 482°F
- Particle Size: < 20µm (micron)
Optical Properties @ 23°C (73.4°F):
- Spectral Transmission:
- < 10% @ 900 nm
- < 20% @ 1,320 nm
- < 45% @ 2,500 nm
See Datasheet for additional properties and application notes
Datasheet
SDS (Part A)
SDS (Part B)
Mixing Instructions
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