On 6 Oct 2016 at 4:59, Nigel Burtt wrote:

> Are "solvent bubbles" a peculiar problem with this type of conformal
> coating or a generic problem for coatings? 
> 
> Hypothetically if coating penetrates under the body of a low stand-off
> component and a solvent bubble remains trapped under there after the
> cure/dry, could that bubble "pop" under thermal cycling or high stress
> service environment with enough force to fracture the solder joints on
> the part?

Just a guess, but I would be afraid that the solvent (which is 
assumed to be away after curing) remains for "ever" or at least long 
enough to make trouble. Remaining solvent in any traps does, what it 
is supposeed to do: solve stuff, especially if it is well trapped in 
its own bubble and has in the worst case really long time to attack 
stuff.

Regards

Matthias

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