From the description TBFFH - that rings an old electronic bell.

The semiconductor market used black - a carbon filled (almost looked
like a spray on )
- foam to provide an ohmic short between transistor and IC 'legs'.  I
have many a sheet of it
with parts on that crumbled.  I suspect the black is appealing to some
for contrast
and the sheets were perhaps cheap.  Harris in Florida and NASA - might have
dumped a number of surplus sheets.  PC part houses used it by the 'yard'.

Martin

[log in to unmask] wrote:
> Fabio and others,
>
> I have just finished unpacking a collection that Tim Pearce and I picked
> up in Florida. The collection was meticulously cataloged. About 80% of the
> collection was fossil material, 20% recent. Some of the specimens were
> stored in open trays with foam in them, some in plastic boxes with foam.
> Most of the foam was black, some was green. I started referring to it as
> the "black foam from hell."
>
> I wish that I had kept some notes while unpacking the collection, however,
> I did not. The collection was built over 30-40 years. Some of the
> specimens may have been exposed to the foam for a long time. Sometimes the
> foam was stable and spongy, most of the time it was crumbly and
> disintegrated in your hand, other times it was a doughy consistency.
> Shells that were exposed to "the black foam from hell" sometimes showed no
> changes (at least to the naked eye), most of the time they did show
> changes. The changes ranged from some discoloration of the shell all the
> way to the surface of the shell being a powdery mess. The reaction seemed
> to be due to contact as the shell surface that was not in contact with the
> foam seemed to be unaffected. The foam seemed to be a polyurethane foam
> (foam rubber) and this product should be banned from any collection.
>
> Polyethylene foam tends to be harder, not as compressible as polyurethane
> foam. For this reason, it may not meet the needs of some collectors. One
> can use polyethylene fiber but it may catch on some frilly or spinous
> shells.
>
> An interesting aspect of polyethylene foam is what agent is used to foam
> or puff-up the material. If nitrogen is used, then the gas in the foam is
> neutral and will cause no problems down the road. It is possible that the
> foaming agent may not be archival. For this reason, I like procuring
> material from suppliers who can provide such information or purchase from
> a firm dealing with archival materials. Some of them are listed at the end
> of my chapter (glad you liked it).
>
> Regards,
> Charlie
> .................................................
> Research Associate - Section of Mollusks
> Carnegie Museum of Natural History
> Pittsburgh, PA, USA
>
> Assistant Professor - Family Medicine
> Fellow-American Academy of Family Practice
> Fellow-Academy of Wilderness Medicine
>
> ----------------------------------------------------------------------
> [log in to unmask] - a forum for informal discussions on molluscs
> To leave this list, click on the following web link:
> http://listserv.uga.edu/cgi-bin/wa?SUBED1=conch-l&A=1
> Type your email address and name in the appropriate box and
> click leave the list.
> ----------------------------------------------------------------------
>
>
>

--
Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
TSRA, Life; NRA LOH & Endowment Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Founder
IHMSA and NRA Metallic Silhouette maker & member.
http://lufkinced.com/

----------------------------------------------------------------------
[log in to unmask] - a forum for informal discussions on molluscs
To leave this list, click on the following web link:
http://listserv.uga.edu/cgi-bin/wa?SUBED1=conch-l&A=1
Type your email address and name in the appropriate box and
click leave the list.
----------------------------------------------------------------------