18 SMT007 MAGAZINE I AUGUST 2019
resistance to condensation, corrosion, tin-
whisker mitigation, and dielectric re-enforce-
ment. 2K coatings are also hydrophobic, which
gives improved humidity and moisture protec-
tion—including salt mist—making 2K an excel-
lent choice for automotive electronics as well
as other tough outdoor applications.
Some 2K materials can be reworked with
comparative ease despite their greater thick-
ness and enhanced chemical resistance. There
are materials within the range that are for-
mulated to be opaque and coloured to both
improve machine AOI recognition and manual
inspection but can also be used to hide board
designs. 2K coating materials will still give sig-
nificantly improved protection at lower-film
builds compared with traditional materials due
to their improved ability to cover component
leads and other sharp edges.
The solvent-free range of 2K materials signif-
icantly improves the reliability of assemblies in
automotive, aerospace, and industrial applica-
tions whilst simultaneously offering faster cur-
ing characteristics, lower odour, and improved
health and safety characteristics than other
100% solids technology, such as UV-curable
acrylated materials.
SMT007
Phil Kinner is the global business
and technical director of conformal
coatings at Electrolube. Kinner is
also the author of
The Printed
Circuit Assembler's Guide to…
Conformal Coatings for Harsh
Environments.
Visit I-007eBooks.com to download
this and other free, educational titles.
Figure 10: Effortless application of 2K coatings using PVA "VPX-2KS" spray valve.
