Joe G Malley@MACDERMID 09/02/98 02:43 PM Kathy, The replacement of a di-functional resin system with a tetra-functional resin system should make the PWB's more reliable. The tetra-functional material will typically have a higher Tg and a lower z-axis expansion value. The lowering of thermal expansion should put less stress on the barrel of the hole and on the interconnects during assembly. I can't comment on the solder mask issues as I have no experieince with one of the masks. Joe Malley ################################################################ TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################