Hi,

I have two things to say, one is that all the conformal coatings absorb
moisture over time.  I believe the one that has the lowest absorption rate
is Parylene; by an order of magnitude.

Your end choice should also include other factors like, solvent resistance,
oil, acid..., temperature cycles, serviceability.. etc.  dependent on where
and how the product is used outside.

-Brent





-----Original Message-----
From: Steve Gregory [mailto:[log in to unmask]]
Sent: Thursday, September 04, 2003 3:35 PM
To: [log in to unmask]
Subject: [TN] Silicone conformal coating


Hi All!

I know when you look up properties for Silicone conformal coating, it
usually states that it has good moisture resistance, but is it really that
good?

I've heard that it is somewhat permeable to moisture, that if you were
worried about moisture, and the assembly were going to see the outside
environment, you would be better off with an acrylic, or urethane coating.

Any thoughts?

Thanks!

-Steve Gregory- ---------------------------------------------------
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