So it would not be advisible to rinse the panels with water immediately after they exit from the etcher? ______________________________ Reply Separator _________________________________ Subject: Re: [TN] Ammonia Etchant - Replenisher Author: "TechNet Mail Forum." <[log in to unmask]>, at corp Date: 1/21/98 9:52 PM At 09:30 22/01/98 PST, you wrote: > Hi all, > > Our ammonia etcher is followed by a replenisher rinse consists of 4 > cascade rinse chambers. As I understand, all ammonia etchers are > followed by some cinfiguration of replenisher rinse, and when I ask > what is the purpose of it, I was told that the rep. rinse is to > 1) Decrease the copper content in the subsequent rinse water > 2) Increase the copper content in the etchant that enter the etcher > 3) Give a finishing touch to the etched panels > > I understand point#1, but not #2 and 3. Why would one want to increase > the copper concentration in incoming etchant? Won't that defeat the > purpose of feeding "fresh" etchant? And how does rinsing in cold, > fresh etchant give a finishing touch to the etched panels? > > Regards, > > Yee T.G. > Hadco Corp. Your point 2 Is not clear to me either . Regarding point 3 : from my own experience this is quality of rinsing . Alkaline etching solutions creates sediments while diluted with water , there are also monovalent copper chlorides , which are insoluble in water . All this is easy removed by fresh etchant . This is important point for someone , who is still running reflow of tin-lead . As well these residues are contributing to copper content in solder stripper . Regards ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ############################################################## ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ##############################################################