Synperonic N

As previously mentioned on the DistList, Synperonic A7 is one of the
replacements recommended by Uniqema (ICI) as a replacement for
Synperonic N in washing textiles. This is based purely on the fact
that its HLB number is very similar to that of Synperonic N and as
mentioned by Mark Vine, it has been used in the industrial sector
for many years prior as a fabric washing product. But it has not, as
far as we are aware, been tested as a product for conservation.
Uniqema are also recommending Synperonic 91/6 for use on hard
surfaces--ceramics, stone, etc. but, again, no testing has yet been
performed. As to the number of Conservators using A7, at the recent
UKIC Textile AGM only one conservator had changed from Synperonic N
and had indeed changed to Synperonic A7. Whether this lack of change
is due to a decline in washing or conservators just using up their
stocks was not made clear.

The other recent comments by Flavia Perugini are also worthy of
comment, and she is correct in her thoughts that Synperonic N and
Triton X100 are the same molecule with a different trade name so we
cannot use this either - unless it can be used and not dumped into
the water system. We have already considered the suggestion of the
use of Triton XL-80N (NOT 80XN) as a replacement and have listed it
for testing.  For the chemists amongst you it is an alcohol
alkoxylate, namely alkoxypolyethyleneoxypolypropy ethanol. Its
critical micelle concentration is less than Synperonic N. It also
comes with a recommendation from Winterthur Museum and Richard
Wolber. The only factor going against it is that it is significantly
more expensive than its competitors and availability in Europe is
not yet clear.

The other surfactants we are testing are Dehypon (fatty
alcohol--nonionic), Saponin (nonionic), Orvus Paste (anionic),
Hostapon T (anionic), Nekanil LN (nonionic) and Irgasol NA
(nonionic).

Some of you may also have heard of the use of Pluronics (EO-PO block
copolymers) and their suggestion as a replacement which we were
considering. Unfortunately although these do appear to clean quite
well (work done at the Boston Museum of Fine Art), they have been
banned under EU regulation as they do not biodegrade within the
specified time limits, even though the precursor and degradation
products are considered environmentally friendly.

We are currently devising a practical washing method which will be
representative of washing performed by a textile conservator and as
soon as this has been established we will begin testing.

I hope this is useful and helps to clarify the picture a little.

John Fields,
Conservation Scientist
Conservation Research Dept.
The British Museum
London WC1B 3DG
+44 171 3238174
Fax: +44 171 3238636


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                  Conservation DistList Instance 13:51
                 Distributed: Saturday, April 15, 2000
                       Message Id: cdl-13-51-001
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