TECHNET Archives

August 2007

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Mike Fenner <[log in to unmask]>
Reply To:
Date:
Wed, 15 Aug 2007 15:05:21 +0100
Content-Type:
text/plain
Parts/Attachments:
text/plain (93 lines)
Just for completeness:
Some water soluble and all water based fluxes (AKA VOC free) will have
surfactants or surfactant like materials, and these can foam. Surfactants
can respond synergistically when mixed.
By Sod's Law  - Murphy's Law in US - you could well have stumbled on such a
synergistic foaming combination..... 



Regards 

Mike


-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of R Sedlak
Sent: Tuesday, August 14, 2007 6:00 PM
To: [log in to unmask]
Subject: Re: [TN] Aqueous batch cleaner foaming

Rob:  See below, where I attempt to answer...

Rob Strecker <[log in to unmask]> wrote:
Does this mean that combining different flux chemistries will not contribute
to foaming?... Probably not..

Is there enough flux left over on the boards from SMT to be a major
contributor to foaming?  ... It would appear you have already answered that
question... fluxes contain surfactant-like  components, and surfactants can
foam  at  low ppm levels. 

Just to clarify, we are on the low sided of our wash temperature, we are not
currently using a defoamer or saponifier, just pure DI water.  
BINGO!  No wonder you are getting foaming!

We have also seen foaming during the first wash load with a fresh water
change out.  How important is it to have our wash tank completely clean of
all previous wash residues before we refill with fresh water?    REAL
IMPORTANT.

Can minimal residues cause major foaming in the next wash?    
You seem to be proving that...

Purchasing a defoamer at this point is not an option, it will be used as a
last resort.  We have a run coming up that we will be separating and washing
SMT boards pre-wave and washing them again post-wave then washing the last
batch after it's been through both processes (worst case) all with fresh
water.  What are some of the risks associated with board wash foaming?
Primarily rinse issues...

If some foaming residue is left on the boards what would they look like and
what problems could they cause, if any?

You are now asking a question beyond my experience..

Rudy Sedlak
RD Chemical Company


       
---------------------------------
Building a website is a piece of cake. 
Yahoo! Small Business gives you all the tools to get online.

---------------------------------------------------
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 email, its content and any files transmitted with it are intended solely for the addressee(s) and may be legally privileged and/or confidential. If you are not the intended recipient please delete and contact the sender by return and delete the material from any computer. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. 

Messages sent via this medium may be subject to delays, non-delivery and unauthorized alteration. This email has been prepared using information believed by the author to be reliable and accurate, but Indium Corporation makes no warranty as to accuracy or completeness. In particular, Indium Corporation does not accept responsibility for changes made to this email after it was sent. Any opinions or recommendations expressed herein are solely those of the author. They may be subject to change without notice.***

---------------------------------------------------
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
-----------------------------------------------------

ATOM RSS1 RSS2