LOCTITE ECCOBOND EN 3915T

Harmonization Code : 3907300090 | Polyacetals, other polyethers and epoxide resins, in primary forms; polycarbonates, alkyd resins, polyallyl esters and other polyesters, in primary forms

Main features

Thixotropic formulation to prevent flow and ensure clean application
Fast heat cure for improved throughput and manufacturing efficiency
Low CTE and halogen-free for reliability and environmental compliance

Product Description

LOCTITE ECCOBOND EN 3915T is a thixotropic, black, heat-curable epoxy encapsulant specifically formulated for flip chip device applications. Its unique rheology ensures controlled material flow, allowing the encapsulant to remain exactly where it's dispensed. This minimizes liquid migration and prevents undesired spreading or displacement, leading to improved consistency and reliability in device performance.

Designed for manufacturing environments that demand precision and speed, LOCTITE ECCOBOND EN 3915T features a fast cure profile—curing in just 7 minutes at 160 °C. It also offers a low coefficient of thermal expansion (CTE) and a high glass transition temperature (Tg) of 130 °C, providing excellent thermal cycling stability. Furthermore, it is halogen-free, supporting compliance with global environmental standards.

Product Key Features

Specifically designed for flip chip device applications.
Thixotropic formulation - ensures precise application onto substrate.
Low CTE - minimizes stress due to thermal expansion.

Product Family
EN 3915T

1. Select Package Type

30cc Syringe

Catalog Product

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Shortest leadtime

Shipping in 6 - 8 weeks

Contact for Pricing

Packaging

TDS, SDS & Technical documents

Specifications
Additional Information

Technical Specifications

General Properties

Pot Life

Pot Life
Pot life is the amount of time it takes for the viscosity of a material to double (or quadruple for lower viscosity materials) in room temperature after a material is mixed.

It is closely related to work life but it is not application dependent, less precise and more of a general indication of how fast a system is going to cure.

24 hours

Specific Gravity

Specific Gravity
Specific gravity (SG) is the ratio of the density of a substance to the density of a reference substance; equivalently, it is the ratio of the mass of a substance to the mass of a reference substance for the same given volume.

For liquids, the reference substance is almost always water (1), while for gases, it is air (1.18) at room temperature. Specific gravity is unitless.

1.66

Shelf Life Shelf Life Shelf life is the amount of time after manufacturing that a product is guaranteed to retain its properties. It differs vastly per product and it is based on temperature and storage conditions. The properties can be guaranteed for the temperature and time range indicated on the TDS since those are the ones tested to be the best for the product.
Shelf Life @ -40°C	180 days

Physical Properties

Thixotropic index

Thixotropic index
Thixotropic Index is a ratio of a material s viscosity at two different speeds in Ambient temperature, generally different by a factor of ten.

A thixotropic material s viscosity will decrease as agitation or pressure is increased. It indicates the capability of a material to hold its shape. Mayonnaise is a great example of this. It holds its shape very well, but when a shear stress is applied, the material easily spreads.

It helps in choosing a material in accordance to the application, dispense method and viscosity of a material.

3.5

Viscosity

Viscosity
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

22,000 mPa.s

Mechanical Properties

Storage (DMA) Modulus
Storage (DMA) Modulus @ 25°C	9,400 N/mm2

Thermal Properties

Coefficient of Thermal Expansion (CTE) Coefficient of Thermal Expansion (CTE) CTE (Coefficient of thermal expansion) is a material property that is indicative of the extent to which a material expands with a change in temperature. This can be a change in length, area or volume, depending on the material. Knowing the CTE of the layers is helpful in analyzing stresses that might occur when a system consists of an adhesive plus some other solid component.
Coefficient of Thermal Expansion (CTE) , α1 Coefficient of Thermal Expansion (CTE) , α1 CTE α1 (alpha 1) is the slope of the Coefficient of thermal expansion in a temperature range below the Glass transition temperature (Tg). It explains how much a material will expand until it reaches Tg.	24 ppm/°C
Coefficient of Thermal Expansion (CTE), α2 Coefficient of Thermal Expansion (CTE), α2 CTE α2 (alpha 2) is the slope of the Coefficient of thermal expansion in a temperature range above the Glass transition temperature (Tg). It explains the extent to which a material will expand after it passes Tg.	103 ppm/°C

Glass Transition Temperature (Tg)

Glass Transition Temperature (Tg)
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.

130 °C

Additional Information

Cure Schedule

7 minutes @ 160°C

Alternate Cure Schedule

10 minutes @ 150°C, or
20 minutes @ 130°C

Thawing

Typical thaw times are listed as follows: 1.5 hours for 30 cc syringes 2 to 3 hours for 55 cc syringes
Allow container to reach room temperature before use.
After removing from the freezer, set the syringes to stand vertically while thawing.
DO NOT re-freeze. Once thawed to 25°C, the adhesive should not be re-frozen.