The cause of the bubbles
Reason 1: The bubble is brought into the
process of glue mixing and glue filling. The wrong stirring method in the
process of glue mixing is easy to bring the air into the glue liquid. If the
viscosity of electronic potting glue is large, the bubble will be difficult to
eliminate. The improper filling process is also easy to bring air into the glue
liquid.
Reason 2: Bubbles produced in the curing
process; Too fast curing speed, high heat release temperature, glue curing
shrinkage rate, electronic sealing glue in the solvent, plasticizer add too
much are easy to produce bubbles in the curing process.
Reason 3: There is oil on the surface of
the potting compound, and there is a layering phenomenon before use. It should
be fully stirred during use.
The above three situations will affect the
appearance of the potting glue and will affect the smoothness and gloss of the
potting glue surface.
Methods to eliminate air bubbles
1. Potting with a professional electronic
glue filling machine. The professional electronic glue filling machine has both
mixed glue filling and vacuum glue filling device, which is convenient and
fast, suitable for large-scale production, and requires enterprises with
certain strength.
2. Before adjusting the glue, heat the glue
at 25-30°C, and then mix the electronic potting glue in proportion. When mixing
glue, stir clockwise, the speed is uniform, not fast and slow. When pouring
glue, the speed should be uniform, otherwise it is easy to generate air
bubbles.
3. Use low-viscosity electronic potting
glue, because low-viscosity silica gel is easier to discharge air bubbles.
It is recommended to choose high-quality
products, because high-end products have high elasticity, high toughness, high
tensile force, high adhesion and adhesion, etc., and the products after potting
can withstand various In outdoor environmental tests, it can maintain good and
stable performance for 2 years or longer, and the change in the shrinkage rate
of the glue is very small. At the same time, the high-end has special
requirements in terms of performance, that is, it has additional matte, thermal
conductivity, and flame retardant properties.
