Helen Coxon and Julia Fenn
The traditional method of labelling artefacts by sealing an ink identification number between two layers of varnish is not satisfactory for plastic artefacts. Solvents in the inks and the varnish can interact with the artefact, initiating chemical and physical breakdown such as staining, deformation and stress cracking. In some cases the damage is progressive and is caused by solvents which do not appear to have any effect on the plastic either by dissolution, absorption or leaching of additives.
Customized labelling kits can be made for each individual type of plastic, but this requires accurate pre-identification to ensure that the correct one is used. This paper will discuss the various labelling methods used by museums and collectors and our own search for a solution that can safely be used by non-conservators on any plastic, without the need for pre-identification.