Datasheet

Page 4
To ensure penetration of the coating beneath the components and in confined spaces, spray the assembly from
all directions to give an even coating. After spraying, the boards should be placed in an air-circulating drying
cabinet following the curing schedule highlighted on page 4/5.
Dip Coating
Ensure that the coating material in the container has been agitated thoroughly and has been allowed to stand
for at least 2 hours for all the air bubbles to disperse.
Conformal Coating Thinners (DCT) should be used to keep the DCA coating at a suitable viscosity for dipping
(180 – 250mPa s @ 20°C). DCT is added periodically as the solvent evaporates. The viscosity should be
checked using a viscosity meter or "flow cup". The board assemblies should be immersed in the DCA dipping
tank in the vertical position, or at an angle as close to the vertical as possible. Connectors should not be
immersed in the liquid unless they are very carefully masked. Electrolube Peelable Coating Masks (PCM/PCS)
are ideal for this application.
Leave submerged for approximately 10 seconds until the air bubbles have dispersed. The board or boards
should then be withdrawn slowly (1 to 2s/mm) so that an even film covers the surface. After withdrawing, the
boards should be left to drain over the tank or drip tray until the majority of residual coating has left the surface.
After the draining operation is complete, the boards should be placed in an air-circulating drying cabinet
following the curing schedule (shown below).
Brushing
Ensure that the coating material has been agitated thoroughly and has been allowed to settle for at least 2
hours. The coating should be kept at ambient temperature.
When the brushing operation is complete, the boards should be placed in an air-circulating drying cabinet
following the curing schedule (shown below).
Drying Times and Curing Conditions
The properties gained from DCA are dependent on the curing schedule employed. It is essential that the
coating be allowed a minimum of two hours drying time at ambient temperature prior to any heat curing. This is
necessary to allow the solvent system to evaporate.
Ambient Ambient curing is via solvent evaporation only. Eliminating the heat curing step will reduce
solvent resistance. Other properties, such as resistance to humid and corrosive environments,
may also reduce but still meet the requirements of many industry standards. Coated boards
should be left at room temperature for the solvent to evaporate; extraction is required in the
curing area.