EPO-TEK® 302-3M Optically Opaque Black Epoxy, Room Temperature Cure (2.5g)

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 for 3 Hours. Available in a 2.5-gram packet.

Features of 302-3MBLK:

• 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. Fibers of glass or plastic. Ferrules of glass, quartz, stainless steel, Kovar, or ceramic)
• 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:

• Color (before cure): 
  • Part A: Black
  • Part B: Clear/Yellow Tint
• Consistency: Pourable liquid
• Viscosity (23°C): 800-1,600 cPs
• Glass Transition Temperature (Tg): ≥ 55°C
• 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)

Electrical and Thermal Properties:

• Volume Resistivity @ 23°C: ≥ 5 x 10¹² Ohm-cm
• Dielectric Constant (1KHz): 3.41
• Dissipation Factor (1KHz): 0.011 

Optical Properties @ 23°C:

• Spectral Transmission:
  • < 10% @ 900 nm
  • < 20% @ 1,320 nm
  • < 45% @ 2,500 nm

See Datasheet for additional properties and application notes