Lisa: 1. Why not apply the a UV curable nomenclature ink to directly the tin final finish after processing. Cure it with a conveyorized UV oven and eliminate the high temp/time bake. 2. If you can not use a UV ink there are two component epoxy based nomenclature inks that will cure at room temperature or slightly elevated temperatures. 3. I don't know what you are using for an ink or what your surface prep process is but there are inks available, again two component epoxies that should bond well to copper if prepped right. I could recommend a supplier off line. 4. Do you really need to put it directly onto the metal? Can a continuos web of soldermask be placed underneath it to aid the adhesion? Michael Barmuta Staff Engineer Fluke Corp. Everett WA 425-356-6076 -----Original Message----- From: Lisa Angle [mailto:[log in to unmask]] Sent: Friday, January 05, 2001 11:56 AM To: [log in to unmask] Subject: Re: [TN] Nomenclature with Immersion Tin/Silver I agree with you on the point of putting nomenclature and mask on before the tin process. I have seen temperature's detrimental affects on tin intermetallics and therefore the solderbaility of the deposit, and do not want to go down this path of disaster. However, I am still faced with the issue of nomenclature peel off of metal surfaces after the immersion tin process. At first glance, the problem seemed to be undercut of the copper surface under the nomenclature. However, I ran some tests where I increased my nomenclature font to very large mil thickness and still experienced the problem, that is what has lead me down the chemical bond attack theory. Have you successfully applied nomenclature to metal surfaces and immersion tinned the boards and seen no peel? Does anyone put nomenclature on metal surfaces and immersion tin them with success? I have no problem with the nomenclature on mask areas. These spots do not experience any type of peeling. Thanks in advance. Lisa Don Vischulis <[log in to unmask]>@IPC.ORG> on 01/05/2001 02:37:48 PM Please respond to [log in to unmask] Sent by: TechNet <[log in to unmask]> To: [log in to unmask] cc: Subject: Re: [TN] Nomenclature with Immersion Tin/Silver Tony and Lisa: I suggest that you speak to your chemistry supplier about this. Immersion silver finishes contain an organic additive to preserve solderability. I don't know enough about the tin finishes to be certain, but I believe that they use similar organics. Elevated temperatures (used to cure mask and nomenclature) degrade the final finish resulting in diminished shelf life and possibly reduced solderability. IMO the best practice is to apply mask and nomenclature before the final finish. The fewer thermal excursions that the finish is exposed to, the longer the shelf life of the board. Don Vischulis >Lisa, >Being in the pcb manufacturing, we have installed immersion tin as a final >finish surface. >As I suspect, with any immersion process such as tin, silver, gold, >soldermask and nomenclature >adhesion sometimes become bigger problems than the actual process itself. We >experienced >the same problems. Through many agonizing weeks of evaluation we have come >up with using >a predip prior to the application of LPI or legend, which consists of a >diluted version of >an oxide replacement bath. This chemistry contains adhesion promoters for >which gave us the >the ability to withstand IPC tape test. > > >Tony Steinke >Circuit Technologies Inc. >----- Original Message ----- >From: Lisa Angle <[log in to unmask]> >To: <[log in to unmask]> >Sent: Thursday, December 21, 2000 3:45 PM >Subject: [TN] Nomenclature with Immersion Tin/Silver > > >> All, >> I was wondering how you go about putting nomenclature on copper surfaces >> and subsequently processing thru immersion tin or immersion silver without >> experiencing nomenclature peel? I have of course thought of the >> alternative which is to process the boards thru immersion processes and >> subsequently nomenclature them, however, our current inks require a long >> cure time and very high temperature which artificially ages the finishes. >> Thanks. >> Lisa Angle >> Alternative Surface Finish Engineer >> Teradyne >> >> -------------------------------------------------------------------------- >------- >> Technet Mail List provided as a free service by IPC using LISTSERV 1.8d >> 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 delivery of Technet send the following message: SET >Technet NOMAIL >> Search previous postings at: www.ipc.org > On-Line Resources & Databases > >E-mail Archives >> Please visit IPC web site (http://www.ipc.org/html/forum.htm) 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 1.8d >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 delivery of Technet send the following message: SET Technet NOMAIL >Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives >Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional >information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 > ---------------------------------------------------------------------------- ----- > > ***************************************** Get your N/Connect Internet account today. Call today toll free 1-888-644-0728. http://www.nconnect.net, or email [log in to unmask] ---------------------------------------------------------------------------- ----- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d 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 delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) 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 1.8d 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 delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) 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 1.8d 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 delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------