Eddie Most immersion silver chemistries include an anti-tarnish over coating. If however you need some additional protection you might try an aqueous immidazole coating. Immidazole is a compound that can be purchased from most chemical houses and was used successfully as an OSP by AT&T for many years. Best regards Lee J. Lee Parker, Ph.D. JLP Consultants LLC 804 779 3389 ----- Original Message ----- From: "Eddie Rocha" <[log in to unmask]> To: <[log in to unmask]> Sent: Monday, July 17, 2006 5:05 PM Subject: [TN] silver anti-tarnish > I've been asked by a customer to provide silver coated > PCB's with an anti-tarnish coating. This is a first for me. > Is anybody else applying an anti-tarnish to silver coated > PCB's? Is this a typical expectation from PCB assemblers? > Will any anti-tarnish suffice or does silver require a > specific anti-tarnish? > > Thank you in advance, > Eddie Rocha > > --------------------------------------------------- > Technet Mail List provided as a 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 > 847-615-7100 ext.2815 > ----------------------------------------------------- > --------------------------------------------------- Technet Mail List provided as a 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 847-615-7100 ext.2815 -----------------------------------------------------