It is definately recommended that once the paste is brought to room
temperature after refrigeration and a portion is removed, you may put the
remaining portion back into the refrigerator with several requirements:
A)That the relative humidity of the environment was relatively low (<40%) -
this will ensure that no condensation or minimal condensation will occor in
the jar; and B) that the seal on the jar is complete, make sure the lip of
the jar is clean and tighten the lid down as hand tight as possible.

AIM Products manufactures a past which can remain unrefrigerated for 6
months in ambient conditions; I know of many small manufacturers who use
this paste for that reason; it is a very stable formulation and lends itself
to small batch processing.

Feel free to browse their website at www.aimsolder.com

Kevin Hogan
Midwest Tech Services.
========================================

From:
To: MS Outlook::[log in to unmask]

Subject: [TN] Solder paste refrigerated after the container is opened.
Date: 2/23/00 3:28 PM

Hi Techneters,

This questions is mostly geared towards the small manufacturers that does
not use that much paste, but all comments are welcomed.  Most manufactures
recommend you store your paste in a refrigerator and keep the temperature at
32-50°F.  We do this, but since we do not use that much paste, we will open
a jar and apply the required amount of paste on our stencil.  Our biggest
production amount only requires us to apply paste to our stencil maybe twice
or three times a day.  I was told by an outside source that once we open the
jar of paste we can not put it back in the refrigerator.  One reason they
said was we are exposing the paste to the air and once this happens you need
to use the paste ASAP.  That's a problem for us since we do not use that
much to begin with.  Currently, we will open the jar and take what we need
and then put the jar back into the refrigerator, it may be two days before
we need to use the paste again.  How do the small shops handle their paste?


Thanks in advance,

Jim West

##############################################################
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.
If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or
847-509-9700 ext.5365
##############################################################

##############################################################
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.
If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or
847-509-9700 ext.5365
##############################################################