PD 977
SMT-Adhesive
Low Temperature Fast Curing SMT-Adhesive
Description
PD 977 is a thermosetting single-component, solvent-free
polymer adhesive, developed for the surface mounting of
SMT components on to PCBs and bare substrates.
PD 977 has been optimised for low temperature (< 100°C )
curing properties.
The rheology of this glue is adapted for high-speeddispensing.
It allows for very low Z-Height-returns - the
height above the board that the dispense head will retract to
upon completion of the dispense cycle.
Special advantages
· Very wide processing window, no tendency to string.
· Specially developed for high-speed dispensing.
· Dispensing with very low Z-Height-return possible.
Physical characteristics
Colour: red
Homogeneity: no particles >50 μm
Adhesion: ³ 25 N/mm2 at room
temperature.
Processing
The adhesive is suitable for machine and manual
dispensing.
Stencil printing is possible.
Curing
The standard curing conditions are: 90°C (195°F) / 3’.
Max. curing temperature should not be higher than 125°C
(255°F). The minimum* curing times in tunnel type oven
are shown in the following list.
80°C (175°F) 90°C (195°F)
5 ' 3 ’
Graphic Curing Time; page 2
* Optimal curing conditions depend on the oven.
Cleaning
Before curing:
The uncured adhesive can be removed with alcohol or water
based cleaning materials. Please contact your local
representative for specific recommendations.
The cleaned parts must be completely dry before installing
them in the machine.
After curing:
Because of the known residual thermoplasticity of the cured
adhesive, defective components can be easily replaced by
heating (with hot air) the cured adhesive joint above 100°C.
After removing the component (torsion movement), the hot
air should be focused on the remaining adhesive in order to
remove it with a sharp tool.
Packing
The adhesives PD 977 can be filled in various machinespecified
syringes.
Storage
Storage time:
6 months in a refrigerator, at a storage temperature of 5 -
12°C (40 - 54°F).