rejected [why??}, and resending message below -----Original Message----- From: Alderete, Michael Sent: Wednesday, May 19, 1999 11:24 AM To: 'IPCtechnet' Subject: Polyimide, temperature for discoloration and /or pyrolosis [charring] Help. Anyone know what temperature polyimide [in PWB]: a. starts to discolor b. pyrolizes, or chars? Had similar problem at the last company- 3 phase power, 115V AC, runs into rig-flex backplanes on F/A-18 targeting pod. Water [salt water or wash down fluids] was getting into vented elec boxes, and shorting out the 3 phase power. Fire and black stuff all over inside of box resulted. Know very little about current design and circumstances, but our guys think it's a short induced problem. PI material darkens; don't think they see charring in this instance. Thanks in advance Michael ################################################################ 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 ################################################################