Friction-sealing containers

In the UK several major manufacturers of friction-sealing food
containers (including Stewart & Addis) have recently changed from
using polyethylene to polypropylene. At the same time they have also
changed to a shape that is less than helpful for curators and
conservators. These food containers have been used for a couple of
decades to provide sensitive museum objects (eg. archaeological
ironwork) with a buffer to external environmental changes,
particularly relative humidity.

At the Norfolk Museums Service Conservation Lab we are currently
seeking and testing appropriate alternatives to the preferred but now
unavailable old polyethylene design.

We would welcome any information about existing products within the
UK that people feel are a good substitute, and in particular what is
currently used in the USA and Canada instead of the "Stewart Boxes"
that have been so popular here for so long.

We intend to test many products, studying, amongst other things: the
suitability of the material in terms of its effectiveness as an
environmental buffer; the expected longevity of the product; the
emission of catalyst residues and additives; its suitability for
U.V sensitive collections; and general ease of use.

Nigel Larkin.
Palaeontological conservator
Norfolk Museums Service
Conservation Lab, Castle Museum, Norwich
Norfolk, NR1 3JU
United Kingdom
+44 1362 860915
Fax: +44 1362 860385

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                  Conservation DistList Instance 11:12
                  Distributed: Thursday, July 24, 1997
                       Message Id: cdl-11-12-006
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