Bryan, 

We use Humiseal 1B31 and we do not have these problems.  I'm not sure if you can consider a switch or not.  
A good resource is www.humiseal.com.

Eric Kalgren
BFGoodrich Aerospace
Data Systems Division

>>> Bryan Kerr <[log in to unmask]> 07/07 2:39 PM >>>
Hi all,
Any experiences with Humiseal 1B73. I'm finding it tends to pull away easily from a solder resist surface, particularly on boards with heatsinks, along the edge of the heatsink profile. Thermal cycling makes it much worse. Any similar problems out there ?

Bryan