ABLESTIK 77-1S
Harmonization Code : 3919.10.80 | Other self-adhesive plastic rolls not exceeding 20 cm wide.
Main features
- One-Component, Solvent-Free Epoxy for Attaching Surface-Mounted Devices
- Smooth Non-Tailing Non-Sag Consistency
- 91-Day Working Window
Product Description
LOCTITE® ABLESTIK 77-1S is a one-component, solvent-free epoxy adhesive designed for attaching surface-mounted devices to printed circuit boards before wave soldering. The blue material combines electrical insulation and moisture resistance with a soft, smooth consistency formulated to resist tailing and sagging during screening, pin-transfer, or dot-dispensing processes. It provides a typical viscosity of 47,000 mPa·s at 25°C and a 91-day work life at 25°C. Guideline heat-cure schedules range from 3 minutes at 150°C to 10 seconds at 200°C.
Key features
- Controlled adhesive placement: Soft, smooth consistency with no tailing or sagging supports screening, pin transfer, and dot dispensing.
- Electrically insulating: Typical cured volume resistivity is 1.3 × 1012 ohm-cm.
- Fast heat cure: Guideline schedules include 3 minutes at 150°C, 2 minutes at 175°C, or 10 seconds at 200°C.
Applications / Suitable for
- Attaching surface-mounted devices to printed circuit boards before wave soldering
- Screening, pin-transfer, and dot-dispensing processes
- Ceramic capacitor, thick-film resistor, and SOT attachment
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Appearance
Blue
Appearance at room temperature.
Chemistry Type
Epoxy
Thermal Properties
Glass Transition Temperature (Tg)
200 °C
The glass transition temperature for organic adhesives is a temperature region where the polymers change from glassy and brittle to soft and rubbery. Increasing the temperature further continues the softening process as the viscosity drops too. Temperatures between the glass transition temperature and below the decomposition point of the adhesive are the best region for bonding.
The glass-transition temperature Tg of a material characterizes the range of temperatures over which this glass transition occurs.
Thermal Conductivity
0.5 W/m.K
Thermal conductivity describes the ability of a material to conduct heat. It is required by power packages in order to dissipate heat and maintain stable electrical performance.
Thermal conductivity units are [W/(m K)] in the SI system and [Btu/(hr ft °F)] in the Imperial system.
Electrical Properties
Volume Resistivity
1.3×10¹² Ohms⋅cm
Volume resistivity, also called volume resistance, bulk resistance or bulk resistivity is a thickness dependent measurement of the resistivity of a material perpendicular to the plane of the surface.
Physical Properties
Viscosity
47000 mPa.s
Viscosity is a measurement of a fluid’s resistance to flow.
Viscosity is commonly measured in centiPoise (cP). One cP is defined as
the viscosity of water and all other viscosities are derived from this base. MPa is another common unit with a 1:1 conversion to cP.
A product like honey would have a much higher viscosity -around 10,000 cPs-
compared to water. As a result, honey would flow much slower out of a tipped glass than
water would.
The viscosity of a material can be decreased with an increase in temperature in
order to better suit an application
Additional Information
Technical properties
As-supplied / before-processing properties
Typical properties, work-life information, storage conditions, and guideline cure schedules before final processing.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Technology | Epoxy | — | One-component, solvent-free adhesive |
| Appearance | Blue liquid | — | As supplied |
| Viscosity | 47,000 | mPa·s (cP) | Brookfield CP51, 5 rpm at 25°C |
| Specific gravity | 1.5 | — | SDS physical-property value |
| VOC content | 0.2 | g/L | SDS value; method not stated |
| Work life | 91 | days | At 25°C |
| Shelf life | 91 | days | At 5°C |
| Shelf life | 365 | days | At -40°C |
| Recommended cure schedule | 3 | minutes | At 150°C; guideline recommendation |
| Alternative cure schedules | 2 minutes or 10 seconds | — | 2 minutes at 175°C or 10 seconds at 200°C; guideline recommendations |
| Optimal storage | -40 | °C | Store unopened in a dry location; do not refreeze after thawing to 25°C |
Technical properties
After-processing / final-state properties
Typical physical, thermal, electrical, moisture-exposure, and bonded-joint properties of the cured adhesive. Values are reference data and are not product specifications.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Glass-transition temperature | 200 | °C | Method and cure condition not stated |
| Coefficient of thermal expansion — below Tg | 55 | ppm/°C | TMA; cure condition not stated |
| Coefficient of thermal expansion — above Tg | 110 | ppm/°C | TMA; cure condition not stated |
| Thermal conductivity | 0.5 | W/(m·K) | At 121°C; method, specimen geometry, and cure condition not stated |
| Hardness | 94 | Shore D | Cure condition and test method not stated |
| Weight loss at 250°C | 0.33 | % | Test method, exposure duration, and cure condition not stated |
| Volume resistivity | 1.3 × 1012 | ohm-cm | Test method and cure condition not stated |
| Volume resistivity after water immersion | 1.1 × 1011 | ohm-cm | After 24 hours of water immersion; immersion temperature, test method, and cure condition not stated |
| Dielectric constant | 4.6 | — | At 1 kHz |
| Dissipation factor | 0.017 | — | At 1 kHz |
| Device shear strength — ceramic capacitors | 1,000 | grams | Device dimensions, cure condition, test method, and test temperature not stated |
| Device shear strength — thick-film resistors | 2,000 | grams | Device dimensions, cure condition, test method, and test temperature not stated |
| Device shear strength — SOTs | 3,000 | grams | Device dimensions, cure condition, test method, and test temperature not stated |
| Lap shear strength — aluminum to aluminum | 13.79 (≥2,000) | N/mm² (psi) | Tested at 25°C; surface preparation, bondline, cure condition, and test method not stated |
