Issue link: https://iconnect007.uberflip.com/i/1022231
76 SMT007 MAGAZINE I SEPTEMBER 2018 In my previous column, I touched upon the environmental impact of conformal coatings and how the industry is striving to find new formulations—principally water-based, sol- vent-free materials—that have minimal envi- ronmental impact. In this column, I will return to the Q&A formula that my colleagues have adopted in past issues and attempt to answer trending queries from our customer base on coating properties, selections, and applica- tions. In addition, I hope to shed more light on coating problems posed by electronics miniaturisation, which is certainly exercising the minds of designers and production engi- neers from a growing cohort of customers in the consumer electronics sector. Without fur- ther ado, here are five of the best questions that frequently arise when we enter prelimi- nary consultations with our clients. In an ideal world, what combination of properties would a coating exhibit? The performance requirements of conformal coatings continue to become ever-challeng- ing as electronic assemblies are subjected to increasingly hostile operating environments. The perfect conformal coating would retain high elasticity at both high and low temper- ature extremes and maintain its properties at high temperatures with no out-gassing. It would also provide an excellent barrier to moisture in humid environments and where there is a risk of liquid water splash. It would be highly resistant to solvents and corrosive gases but be easy to remove when repairs or modifications need to be carried out. Ultimate- ly, the perfect coating would be intelligent, self-applying, and free of charge—but that's a whole different ball game! Conformal Coatings: An Evolving Science Sensible Design by Phil Kinner, ELECTROLUBE