Any ionic method, be it an OmegaMeter or any equivalent instrument or
ion chromatography, can detect only ionic contamination that can be
leached out in the solution used. As we do not know the composition of
your gel, nor the nature of your coating, we cannot answer. If it
contains ionic components and is soluble in an IPA/water mixture, the
answer may be positive, otherwise, and more likely, negative. As a
guess, your gel may contain methylene chloride (dichloromethane) as the
active agent, with thickening/rheological agents, primarily to slow down
evaporation of the solvent and to keep it in contact where you wish to
remove the coating. However, it may also contain basic compounds, such
as sodium hydroxide, to assist the attack. This would render it ionic
but it would also render it very dangerous if any residues were left.

What do you use to clean off the gel?

I would suggest that a variant of the so-called "acetonitrile" test
(visual type), using the purest solvent of a suitable type (the same as
you use for cleaning off the gel, but reagent grade) may be a simple way
of detecting residues of gel.

Brian

> Bogert wrote:
>
> 9/4/2001
> My question is, would an Omegameter 600 ionic tester, or
> equivalent, identify the presence of conductive conformal coating
> removal gel after Type UR conformal coating was re-applied after
> rework to remove coating using the conductive stripper (the stripper
> was manufactured by, and recommended by, the Type UR conformal coating
> manufacturer).  Obviously if the gel was trapped under the re-applied
> conformal coating, the test would not detect its presence.  However,
> if the test was performed prior to re-applying the conformal coating,
> would it yield any results that would be useful?  Also, what impact
> would the alcohol in the test solution have on the Type UR coating.

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