10 REMOVAL OF FACINGS, PRESSURE-SENSITIVE ADHESIVE, AND VARNISH

To remove the facings, the Rhoplex N-580 was gelled by the application of a 1:1 mixture of 2-propanol and Stoddard solvent. The facing tissues were then carefully pulled away. Residues of the remaining contact adhesive were removed with cotton swabs charged with a 2:1 mixture of 2-propanol and acetone. This procedure caused the unavoidable partial removal of the varnish layer. The remaining discolored varnish layers were removed with a 2:1 mixture of 2-propanol and acetone. In this case, the removal of the yellowed and blanched varnish layer was a desirable part of the treatment. In other instances where the retention of the varnish is desirable, the selection of Rhoplex N-580 as a facing adhesive should be considered carefully given the solvents needed to remove it.