Removing soot from plaster and silver leaf

Jennifer Dennis <jelemede<-at->gmail<.>com> writes

>I am an objects conservator in private practice.  An artist I know
>recently has had a layer of fine particle, silt-like soot deposited
>on about 20 paintings that include (burnished) Venetian plaster and
>silver leaf (due to work on a chimney).  The soot adheres to
>surfaces and smears if brushed.  I don't have experience with this
>condition.

Removal of soot without contact has been done successfully by using
low temperature atmospheric pressure plasma jets.  It is not very
fast, but in cases as yours where little alternatives are present,
it surely can be a solution.

You can find more information about this technique on the website of
the FP7-European research project 'PANNA'

    <URL:http://cordis.europa.eu/result/rcn/58709_en.html>

or view a Youtube film about it

    <URL:https://www.youtube.com/watch?v=J79rkAqGlSA>

Different partners in this project evaluated the removal of soot on
a number of surfaces with existing commercial plasma torches and
with a new developed torch, designed specifically for the use in
conservation.  This torch works with extreme low temperatures (30-40
deg C) substrate surface temperature) and improved chemical
reactivity compared to commercial available ones.  It is small and
light to use on any surface in ambient air.

We have in our labs torches available which work with a number of
gas mixtures to select the most appropriate cleaning procedure for
each case.  If you need more information or want to have some tests
executed, I would be happy to help.

Patrick Storme
Cultural Heritage Researcher
Faculty of Design Sciences
Conservation Studies
University of Antwerp
Blindestraat 9
B-2000 Antwerpen
Belgium


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                  Conservation DistList Instance 29:30
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