Early phenol-formaldehyde and urea-formaldehyde plastics

James Tapley <jthandbook [at] aol__com> writes

>I have acquired a badly damaged (cracks, losses) art deco Reliure
>Jotau industrial molded "Bakelite" bookbinding. While these bindings
>are always referred to as made of Bakelite I believe, based on the
>unpainted but rather colorful plastic, that they are perhaps made of
>a urea-formaldehyde  plastic. Can anyone suggest a relatively simple
>and non-destructive test for distinguishing between urea- and
>phenol-formaldehyde plastics? ...

An easy way to check the difference is to place a hot needle
somewhere discreet on the piece.  If a white halo is seen around the
needle point on the plastic then you will have Urea-formaldehyde. It
should also give a fishy smell.  Phenol Formaldehyde will have a
medical smell. Even by rubbing a warm hand on it you can often smell
it.

An extremely knowledgeable person who may be able to help you
further is Thea Van Oosten.  She is a senior researcher at the
Netherlands Institute for Cultural Heritage and specialises in
plastic recognition.

Suzanne Kitto
Senior Conservator
Conservation Dept.
Royal Armouries
Armouries Drive
Leeds LS10 1LT


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                  Conservation DistList Instance 18:36
                 Distributed: Sunday, January 30, 2005
                       Message Id: cdl-18-36-020
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