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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.

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

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