agree with Matthias. cure, you get skin 1st (tack free - oxidation or surface cure), it would be hard for bubble to pop, most likely, the least resistance place to expand - adjacent area that is not form the skin - big bubble - bridge few sj... > 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 > > -- > Matthias Mansfeld Elektronik * Printed Circuit Board Design and > Assembly > Neithardtstr. 3, D-85540 Haar, GERMANY > Phone: +49-89-4620 0937, Fax: +49-89-4620 0938 > Internet: http://www.mansfeld-elektronik.de > OpenPGP: http://www.mansfeld-elektronik.de/gnupgkey/mansfeld.asc > Fingerprint: 6563 057D E6B8 9105 1CE4 18D0 4056 1F54 8B59 40EF >