The name CORESOL stands for a coating technology, which
utilizes a method, whose advantages have already been gained for a long time in
other fields of surface coating: the technology of electrostatic spray coating.
With this technology resists and solder masks can be sprayed
on flat substrates like circuit boards, inner layers, hybrids, wafers and LCDs.
High voltage ink is atomized into fine droplets by a rotary bell at speeds of
40000 RPM/min. The droplets follow the electrostatic field lines from the
atomizing apparatus to the substrate and in this way achieve a homogeneous ink
During this process the substrates to be coated are lead
through underneath the spraying apparatus. In this way an optimal ink
exploitation and layer distribution are achieved as the electrostatic field
lines have the same direction as gravity.
There is no preferred direction for spraying, but in any case
a homogeneous structure is attained because of the equipartitional approach
direction of the ink particles. Owing to the dropletwise structure of the ink
layer air occlusions are prevented. The result in case of conductor traces is
an extroordinarily good coverage even of undercuts. In this way higher
dissolutions for following processings as with comparable techniques are
With the application of the electrostatic method holes in the
substrate remain mostly free of ink.
For electrostatic high rotary coating ink of a viscosity up to
300 sec. (measured with a DIN 4 cup) can be utilized.
Therefore the solids content of ink can be increased, which is
advantageous for the structure of higher layer thicknesses.
The CORESOL machines has been especially designed for the
coating of wafers, LCDs, PCBs and hybrids.