ECCOBOND 3707F
Harmonization Code : 3506.91.90.99 | Prepared glues and other prepared adhesives, not elsewhere specified or included; products suitable for use as glues or adhesives, put up for retail sale as glues or adhesives, not exceeding a net weight of 1 kg ; Adhesives based on polymers of headings 3901 to 3913 or on rubber; Other ; Other
Main features
- UV Cure with Heat Backup
- No-Flow WLCSP/BGA Encapsulation
- UV-Fluorescent Inspection
Product Description
LOCTITE ECCOBOND EN 3707F is a one-part, light-yellow no-flow epoxy encapsulant for local protection of WLCSP and BGA devices on circuit boards. The material uses UV cure with a secondary heat-cure initiator for shadowed areas and fluoresces under UV light for visual inspection. Typical viscosity is 3,480 mPa s at 25 deg C, with a 3-day pot life and 180-day shelf life at 2 to 8 deg C. Recommended UV processing uses UVA or UVB at 100 mW/cm^2 for more than 30 seconds. Heat-cure alternatives include 30 minutes at 80 deg C, 5 minutes at 100 deg C, or 1 to 2 minutes at 130 deg C. The cured epoxy has a typical Tg of 36.8 deg C by TMA.
Key features
- UV Cure with Secondary Heat Cure: Thermal cure addresses shadowed areas not directly exposed to UV.
- 3480 cP Viscosity at 25 deg C: Typical uncured rheology applies to the one-component no-flow epoxy.
- 36.8 deg C Glass Transition Temperature: Typical CTE is 50.3 ppm/deg C below Tg and 162.2 ppm/deg C above Tg.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Physical Properties
Thermal Properties
Additional Information
As-supplied / before-processing properties
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Viscosity | 3,480 | mPa s | Brookfield CP51, 25 deg C, 20 rpm; typical |
| Pot life | 3 | days | 25 deg C; typical |
| Shelf life | 180 | days | 2 to 8 deg C; typical |
| UV light intensity | 100 | mW/cm^2 | UVA or UVB; recommended |
| UV exposure time | >30 | s | At 100 mW/cm^2; recommended |
| Heat cure schedule | 30 min / 5 min / 1 to 2 min | - | At 80 / 100 / 130 deg C respectively; guideline |
After-processing / final-state properties
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| CTE below Tg | 50.3 | ppm/deg C | TMA; typical |
| CTE above Tg | 162.2 | ppm/deg C | TMA; typical |
| Glass transition temperature | 36.8 | deg C | TMA; typical |
| Storage modulus | 4,400 | N/mm^2 | DMA at 25 deg C; typical |
