Primal B60A

In Conservation DistList Instance: 29:39 Wednesday, February 24,
2016 I wrote

>My colleague Duygu Camurcuoglu and I have recently started testing
>Primal (Rhoplex) B60A for consolidation of cracks and flaking
>surfaces of archaeological ceramics as alternative to Paraloid B72.

Thank you very much for your feedback.  Our current research is
focused specifically on Primal B60A as an alternative (not a
replacement) to Paraloid B72 in cases where there is a risk of
excessive staining and visual change to the objects or where solvent
based consolidants may cause swelling and collapse of friable
surface particles.

We are up to date with both latest and previous studies and the most
current research/evaluations of poly(vinyl acetate) and acrylic
adhesives/emulsions.  However, none of those studies include Primal
B60A, which is a product different to the other variations of Primal
(Rhoplex).

Primal B60A has been used widely and successfully in stone
conservation, as well as in natural history conservation for
consolidation of bones and bone artefacts.

Without listing all effective properties of Primal B60A we could
confirm that our initial testing shows the following:

    Staining to low fired ceramic and unfired clay is reduced to
    minimum or none

    Low-percentage solution in deionised water penetrates very well.
    Less re-applications needed as the product is not water soluble
    after curing and allows building up of the consolidant only in
    the specific area that's needed

    Minimal amount of the product is used which reduces the risk of
    re-activating salts especially for museum objects within
    controlled environment.  The technical information for Primal
    B60A states that the product has excellent stability to salts.

    It is solvent-free, environmental, H&S friendly

We are realising that Primal B60A is yet to be tested in depth and
it is a great opportunity for knowledge exchange between different
conservation fields.  Please let us know if you have any comments on
the specific use of Primal B60A.

Stefka Bargazova
Specialist Conservator, Ceramics and Glass
Department of Conservation and Scientific Research
The British Museum
Great Russell Street
London WC1B 3DG
+44 20 7323 8295


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                  Conservation DistList Instance 29:41
                  Distributed: Sunday, March 13, 2016
                       Message Id: cdl-29-41-001
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