Thermolignum system

Taylor Samantha <samantha.taylor [at] twmuseums__org__uk> writes

>Has anyone had experience of putting a costume/textile or
>mixed-media collection through the thermolignum process?  What
>criteria did you use to determine what was suitable/unsuitable to
>undergo the treatment process? In particular, how were objects that
>involved plastic dealt with?

Tom Strang at CCI has tried heat treatment on a wide range of
objects, including I believe some made of wax (what they were
infested with I couldn't tell you, perhaps they were just test
pieces, or part of a composite object). The criteria for treatment
with heat must be whether the temperature exceeds the melting point
of any of the materials in the object. If some could be subject to
melting eg. plastics, and you cannot determine that the melting
point is above the kill threshold (52 degrees C, I think it is) then
I wouldn't risk it. Freezing to minus 30 degrees C will kill all
stages of any insect's life cycle too, without the risk of damage.
Any embrittlement from low temperatures would be temporary. Perhaps
you should be looking to freeze instead. There is more preparation
i.e. bagging/sealing in polythene to avoid moisture vapour
condensing on the the cold object. It can be a good thing to leave
objects in bags whilst in storage however, if you are unsure that
the building is pest free.

You need also to investigate what has caused the outbreak. Treatment
without dealing with the underlying problem(s) is probably not the
best way forward. My apologies if this is stating the obvious.

Ian Fraser
Furniture Conservator
Temple Newsam House
Leeds Museums and Galleries
Leeds LS15 0AE


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                  Conservation DistList Instance 17:3
                   Distributed: Friday, June 20, 2003
                        Message Id: cdl-17-3-009
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