I wish I could remember all I forgot on this subject. I do remember wishing I could count on normal copper oxidation to do the job other processes should. In my polyimide days, cuprous (is this the red stuff) was used over cupric (is this the black stuff) to promote inner laminar bond during relamination. Has double treat (brass plating copper foil?) fulfilled its promise? I guess I'm asking more questions than providing answers. I'm just suprised the question persists. Another frustration I have is when did the customer specify a process? What happened to concurrent engineering. The master drawing and specification used to call out only what was acceptable - not how to make it happen. Earl Moon ################################################################ 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 ################################################################