In a previous incarnation, we found that the cardboard had serious 
     effects on solderability when it was stored for over 3 months.


______________________________ Reply Separator _________________________________
Subject: RE: Cardboard boxes
Author:  [log in to unmask] at internet
Date:    7/26/96 1:47 PM


I know of no published articles on the extent of free sulfur in cardboard 
manufacturing.

In our product, we are extremely sensitive to free sulfur and the corrosive 
effects it has on the silver electrodes of our piezoelectric ceramics.   We 
have successfully shipped and stored these ceramic elements in cardboard 
boxes for years without problems.  We have done extensive testing of any 
product that comes in contact with this ceramic from production processes, 
soldering, assembly etc.  We have discovered that free sulfur in cardboard 
was the least likely component of contamination.

The bottom line is, when in doubt, test!  The test is accurate and 
inexpensive.  Tape a small piece of pure silver foil to the material in 
question, and age at 150 F for 48 hours.  Examine the silver foil for signs 
of discoloration.  Be carful, as many types of tape have free sulfur.

Darrell Bonzo
EDO Corporation/Acoustic Division
 ----------
From: 'mail@ih <[log in to unmask]>'
To: dabonz; jasatt; 'mail@ih <[log in to unmask]>'
Subject: Cardboard boxes
Date: Friday, July 26, 1996 9:12AM


I have heard for years that packaging electronic components(terminals,
connectors, etc.) in cardboard boxes is bad.  The problem being that the
sulfur in the cardboard will eventually contaminate the solderable surfaces,
 resulting in solderability problems.  The solution is to package in a
non-permeable sealed bag(plastic) inside the box.  I have never been able
to find any documentation to prove or dis-prove this issue.  If anyone
knows of a published aricle, please contact me with the info.

Thanks

[log in to unmask]

***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To unsubscribe from this list at any time, send a message to:           *
* [log in to unmask] with <subject: unsubscribe> and no text.        *
***************************************************************************

***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To unsubscribe from this list at any time, send a message to:           *
* [log in to unmask] with <subject: unsubscribe> and no text.        *
***************************************************************************


***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To unsubscribe from this list at any time, send a message to:           *
* [log in to unmask] with <subject: unsubscribe> and no text.        *
***************************************************************************