======== Original Message ======== Sender: [log in to unmask] Received: from simon.ipc.org ([168.113.24.64]) by arl-img-4.compuserve.com (8.6.10/5.950515) id LAA26656; Thu, 13 Mar 1997 11:15:38 -0500 Received: from ipc.org by simon.ipc.org via SMTP (940816.SGI.8.6.9/940406.SGI) id KAA29855; Thu, 13 Mar 1997 10:00:40 -0800 Resent-Date: Thu, 13 Mar 1997 10:00:40 -0800 Received: by ipc.org (Smail3.1.28.1 #2) id m0w5ByC-000BCoC; Thu, 13 Mar 97 08:59 CST Resent-Sender: [log in to unmask] Old-Return-Path: <[log in to unmask]> Message-ID: <01BC2F8F.A8BB3080@gateway> From: Ed Cosper <[log in to unmask]> To: "'Darik Leung'" <[log in to unmask]> Cc: "[log in to unmask]" <[log in to unmask]> Subject: RE: Black-oxide layer turned red after pressing Date: Thu, 13 Mar 1997 09:19:30 -0600 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Resent-Message-ID: <"0XKDh2.0.Q0B.rO1Ap"@ipc> Resent-From: [log in to unmask] X-Mailing-List: <[log in to unmask]> archive/latest/11076 X-Loop: [log in to unmask] Precedence: list Resent-Sender: [log in to unmask] Darick, The anomaly we experienced manifested itself in several forms. One of = the strangest was a reddish color on a single trace while all other = traces surrounding it were black. I have heard this referred to a = galvanization in the copper plating area but I'm not sure what causes = this in oxide. By the way, if anyone out there knows the specifics or = mechanics as to what causes this condition, I would like to know. Thanks=20 Ed=20 ---------- From: Darik Leung[SMTP:[log in to unmask]] Sent: Wednesday, March 12, 1997 1:42 PM To: Ed Cosper Subject: Re: Black-oxide layer turned red after pressing Ed Cosper wrote: >=20 > Dear Darik, >=20 > We experienced a similar problem a few years ago, we found that by = putting in a caustic pre-dip and changing it out weekly, we problem went = away. When we would try to extend the bath, it would gradually return. = However, usually we could see a reddish color streaking before we = pressed it. You might have to look close and angle the layer in a light = source. >=20 > Hope this help, >=20 > Ed Cosper > Director, Quality Assurance and Engineering > Graphic Electronics, Inc. >=20 > ---------- Thank you so much for your advice. We will try to investigation this based on your suggestion. Anyway, in your case, did it happened on all board design (not particularly those with thin outer layer), and did the red area confined near the edge of the platen? We did observed such symptoms. Best Regards, *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To subscribe/unsubscribe send a message <to: [log in to unmask]> * * with <subject: subscribe/unsubscribe> and no text in the body. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * *************************************************************************** ======== Fwd by: Anthony (Tony ======== Hi Ed, Give me a call if you would like to get more opinions on the cause of the problem in the oxide process, I believe I can shed some light on the problem. Tony King Elexsys International Inc. Nashua N.H. Phone: 603-886-0066 *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To subscribe/unsubscribe send a message <to: [log in to unmask]> * * with <subject: subscribe/unsubscribe> and no text in the body. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************