Visual effects of selected biocides on easel painting materials

AbstractThis paper reports on the results of experiments to test for visual changes to paint systems after biocidal treatments, using a statistical binary procedure. Four biocides were selected, two of which are fungicides—a quaternary ammoniumorganotin mixture (BioMet 66®)in distilled water and an orthophenylphenol (Lysol®) in a spray— and two of which are fumigants—sulfuryl fluoride (SO2F6), a gas (Vikane®), and nitrogen gas (N2) (as an anoxant). The procedure used to assess the effect of the biocidal treatments was a random field visual scoring regimen by two paintings conservators. The tests were conducted on 30 combinations of linen, rabbitskin glue size, lead white oil ground and oil-based paints. The visual assessment procedure provided information on color change, gloss change, blanching, topography change and precipitation. The results indicated that Vikane adversely affected 10 of 11 pigment systems; Lysol adversely affected six of 11 pigment systems; BioMet 66 had a minor effect on four of 11 p...