Thank you for all your replies. I have asked the same question to our vendor. I am awaiting their reply. Rudy, regarding the additives, is that something that should be specified in the fab requirements or is that a part of "best practices" used for FAB assembly? thanks, Amol ________________________________________ From: TechNet [[log in to unmask]] On Behalf Of R Sedlak [[log in to unmask]] Sent: Friday, August 06, 2010 12:54 PM To: [log in to unmask] Subject: Re: [TN] RE: Discoloration under the soldermask I going to make a wild guess.... I suspect your "discoloration" may be incomplete etching. This can occur when you get immersion Tin on Copper, during photoresist stripping. There are specific additives which SHOULD be in photoresist strippers to prevent this, but many vendors are unaware of this. Rudy Sedlak RD Chemical Company --- On Fri, 8/6/10, Steve Gregory <[log in to unmask]> wrote: From: Steve Gregory <[log in to unmask]> Subject: [TN] RE: Discoloration under the soldermask To: [log in to unmask] Date: Friday, August 6, 2010, 7:09 AM Hi Amol! I have your pictures posted: http://stevezeva.homestead.com/IMG_8358.JPG http://stevezeva.homestead.com/IMG_8359.JPG http://stevezeva.homestead.com/IMG_8360.JPG Steve -----Original Message----- From: Amol Kane [mailto:[log in to unmask]] Sent: Friday, August 06, 2010 9:35 AM To: Steve Gregory; TechNet E-Mail Forum Subject: Discoloration under the soldermask Steve, would you be so kind to put them up on your site?....the discoloration is underneath the soldermask. do any of you guys/gals know what may cause this to happen?. this is across multiple date codes. I am looking for a possible root cause so that I can decide whether or not to reject these boards and issue a corrective action to the vendor. Thanks! Amol ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 847-615-7100 ext.2815 ----------------------------------------------------- ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 847-615-7100 ext.2815 ----------------------------------------------------- ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 847-615-7100 ext.2815 -----------------------------------------------------