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
  • Silver glass die attach
  • Excellent adhesion
  • Excellent RGA moisture results

Product Description

LOCTITE ABLESTIK QMI 2569 is a wide temperature processing, no-dry, silver glass die attach adhesive for the attachment of integrated circuits in both solder seal and glass seal hermetic packages. The material can allow the simultaneous processing of die attach and leadframe embedding, while producing a void-free bondline for maximum thermal dissipation. 

LOCTITE ABLESTIK QMI 2569 shows excellent adhesion when processed between 380°C to 440°C for small die (.300” x .300”), and between 390°C to 440°C for large die. Excellent RGA moisture results are acquired through the use of lead borate glass. This paste can only be used in hermetic packages. The QMI 2569 also offers improved processability by allowing in-line drying during the firing process on die as large as .800” x .800”. Either multi-needle or starfish can apply the material.

LOCTITE ABLESTIK QMI2569 can only be used in hermetic packaging applications.

Product Family
2 oz jar

Catalog Product

Unlike other products we offer, the products listed on this page cannot currently be ordered directly from the website.

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 @ -40°C 365 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.
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
35,800 mPa.s
Chemical Properties
Ionic Content
Chloride (Cl-)
Chloride (Cl-)
The amount of Chloride (Cl-) ion extracted from the product in parts per million (ppm)
10 ppm
Potassium (K+)
Potassium (K+)
The amount of Potassium (K+) ion extracted from the product in parts per million (ppm)
20 ppm
Sodium (Na+)
Sodium (Na+)
The amount of Sodium (Na+) ion extracted from the product in parts per million (ppm)
20 ppm
Mechanical Properties
Tensile Modulus
Tensile Modulus
Tensile modulus is a mechanical property that measures the stiffness of an elastic material. It is the slope of stress / strain curve of a material under direct tensile loading.

It can be used to predict the elongation or elastic deformation of an object as long as the stress is less than the tensile strength of the material. Elastic deformation is caused by stretching the bonds between atoms and the deformation can be reversed when the load is removed.

Tensile modulus is affected by temperature and is an important engineering attribute since we generally want to keep elastic deformation as small as possible.
Tensile Modulus @25°C 2,190 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.
16 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.
250 °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.
60 W/m.K

Additional Information

Firing profile
The firing process for Ag-glass (Silver-Glass) involves the vehicle removal and sintering of the silver-glass composite into a dense, fired film. These steps are conveniently accomplished in a multizone belt furnace with an oxidizing atmosphere (clean dry air).
Optimal temperature ramp rates for solvent removal during organic burnout and densification during sintering of the solids can be obtained through proper temperature programming of each zone and belt speed.

Check the Technical datasheet for target ramp rates for temperature ranges between 40 to 280° C and for die sizes between 5x5 to 20x20 mm. For rectangular die, the largest dimension is typically used to determine the range, and recommended ramp rates decrease as die sizes increase. Ramp rates become significantly faster as the devices progress on the belt to sequentially higher temperature zones in the furnace. Small die can be ran on a large die profile. For example, some customers fire 5 mm die with the 15 mm die profile. Ramp rate is not critical for temperature above 280°C.