LOCTITE D125 F

Harmonization Code : 3907.30.00.90 | Polyacetals, other polyethers and epoxide resins, in primary forms; polycarbonates, alkyd resins, polyallyl esters and other polyesters, in primary forms : Epoxide resins : Other

Main features

Low exotherm
High speed dispensing
Low cure temperature

Product Description

LOCTITE D 125 F is a one-component, heat-curable epoxy adhesive specifically formulated for high-speed dispensing in surface mount technology (SMT) assembly. With its low exotherm and minimal water absorption, LOCTITE D 125 F reduces thermal stress on components while ensuring strong adhesion and process reliability.

This yellow adhesive exhibits excellent non-sag and non-stringing characteristics, enabling precise, clean application for chip capacitors, chip resistors, SOTs, SOICs, and PLCCs. It offers high hot strength and fast curing at low temperatures, making it well-suited for demanding, high-throughput electronic manufacturing.

Applications

Surface mount assembly of chip capacitors and resistors
Bonding SOTs, SOICs, PLCCs, and other SMT components
High-speed, precision dispensing processes
Electronics production requiring low cure temperatures and non-sag adhesives

Specifications
Additional Information

Technical Specifications

General Properties

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 @ 5°C	183 days

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.

1.275

Physical Properties

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

1750000 mPa.s

Electrical Properties

Dielectric Constant

Dielectric Constant
Dielectric Constant (k), commonly known as relative permittivity, is a number relating the ability of a material to carry alternating current to the ability of vacuum to carry alternating current.

It determines the ability of an insulator to store electrical energy and is the ratio of electric permeability in vacuum against the electric permeability of a material.

The lower the dielectric constant (κ) and dissipation factor, the less energy is absorbed from an electric field, making it a much better insulator.

It is a dimensionless property that can be affected by various factors such as the thickness uniformity of a material, insufficient contact between the sample and electrodes, water adsorption and contact resistance.

Dielectric Constant @ 1000 kHz

3.5

Volume Resistivity

Volume Resistivity
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.

1e 14 Ohms⋅cm

Mechanical Properties

Hardness Hardness Hardness is a dimensionless quantity. There is no direct relationship between measurements in one scale and their equivalent in another scale or another hardness test.
Durometer (Shore D)	80

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.

58 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.

85 °C

Thermal Conductivity

Thermal Conductivity
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.

0.3 W/m.K

Additional Information

Cure Profiles
IR or Convection Conveyor Oven:

20 min @ 100 °C
7 min @ 110 °C
2.5 min @ 120 °C
1.5 min @ 150 °C

Convection Box Oven:

30 min @ 100 °C
20 min @ 110 °C
10 min @ 120 °C
5 min @ 150 °C

*Note: Ramp-up should not exceed 1 °C per second

Thawing

Remove the adhesive from cold storage.
Allow the material to reach room temperature (25 °C) before use.
Do not re-freeze once thawed.
Once thawed, apply using the recommended methods.

Directions for Use

LOCTITE D125 F can be applied by dispensing, pin transfer, screen or stencil printing.
Equipment set-up and related product information is available from your Henkel Corporation support group.