There is an inherent difference between LPI and dry film soldermask, in that dry film mask is three-dimensional. LPI mask floods the board, whereas dry film leaves triangulated pockets along the edge of surface features. It is these pockets where solution entrapment occurs. This is why the cleanliness numbers aren't as good with dry film mask. Tom Coyle Field Services Engineer HADCO Corporation *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************