Ralph: Blisters and delamination are just that. They are areas where the soldermask is separated i.e. not bonded to the surface of the PCB. Although they may not be the best, paragraph 2.9.4 has example pictures It can be caused by a variety of things, contamination on the board surface, wrong solvent, incorrect proportioning or mixing of mask components, too high/too low cure temperature, moisture, high process temperatures, etc. The areas typically are raised and lighter in appearance than the surrounding soldermask due to the air pocket between the mask and board surface. Regards Michael Barmuta Staff Engineer Fluke Corp. Everett WA 425-446-6076 -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Ralph Richart Sent: Monday, March 19, 2007 8:58 AM To: [log in to unmask] Subject: [TN] Soldermask Blisters IPC A-600, section 2.9.4 refers to Blisters/Delamination in Soldermask. I am looking for clarification as to what these actually are? How do they manifest themselves? I can't say I've ever seen one, so I am trying to know what one would look like if I hade seen one. thanks Ralph --------------------------------------------------- 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 message (including any attachments) contains confidential and/or proprietary information intended only for the addressee. Any unauthorized disclosure, copying, distribution or reliance on the contents of this information is strictly prohibited and may constitute a violation of law. If you are not the intended recipient, please notify the sender immediately by responding to this e-mail, and delete the message from your system. If you have any questions about this e-mail please notify the sender immediately. --------------------------------------------------- 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 -----------------------------------------------------