Steve,
Take a board that hasn't been processed (if you have one)
and subject it to the same cleaning cycle that you are
currently using. My guess is that the mask will not flake off.
Are these boards being wave soldered? My feeling is that
the soldering operation is loosening the mask and the
cleaning operation just removes it. This is often the case
when the boards are chemically cleaned prior to the
application of solder mask. We are using a secondary
operation in order to plug the via holes, many other Fab
houses do the same.
Ron Hayashi

##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in
the body:
To subscribe:   SUBSCRIBE TECHNET <your full name>
To unsubscribe:   SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or
847-509-9700 ext.5365
##############################################################