I'm not familiar with the molecular chemistry of polyimides, but your hypothesis does not seem very likely. At least with epoxies and polycarbomates, and I assume similarly with other resins, the brominated flame-retardency compounds are not added particles but form an integral chemical part of the resin structure, cross-linked into it. Brian Prasad Godavarti wrote: > Dear Friends: > > we have an interseting situation: we ordered printed wiring boards that wre > made from an Isola p96 laminate and the coupons microsections are showing > what appears to be voids. I understand that these could be brominated > particles that are added to the polyimide resin to make it fire-retardant. > How would we verify this? does anyone else have any stories to share on > what they have seen? I am told this is a finding that may be true only for > Isola's P96 product that hit the market late last year or early this year? > need any words of wisdom we can get. > > --------------------------------------------------- > Technet Mail List provided as a free service by IPC using LISTSERV 1.8e > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet > To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) > To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest > Search the archives of previous posts at: http://listserv.ipc.org/archives > Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 > ----------------------------------------------------- > > --------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------