A Water-Damaged Painting
Canadian Pacific Conservators,
June 2001 - August 2001
Paintings are constructed with many differing materials and expressive methods. Panels, canvas, paper, ivory, metal and walls often support this creative imagery. Other materials and mediums used for painting may include tempera, oil, acrylic, fresco, encaustic, forms of mixed media. An artistís individual technique and interpretation for using materials will influence not only the aesthetic character of the artwork, it will also affect how the artwork will age and respond to the conditions of display, storage, or accidental duress. Paintings and their composite materials will have their own individual response when subjected to moisture and water damage. Paintings on wood panels or boards may develop cracks, warp, or split. Canvas supports may develop wave-like distortion, or lay slack upon its wood stretcher. Water may seep into the fine cracks of a paint layer and result in weakening or dissolving the underlying layers of the artwork.
Paint layers and mixed media will swell and shrink with potential to crack, or, separate and detach from the support. High humidity encourages fungal infestation and rabbit skin glue used on canvas paintings can provide a feast to support bacterial growth. Generally speaking, materials swell or expand when in contact with water or with the increase of moisture in the environment. Conversely, when the moisture or water decreases, the materials dry and shrink. This expansion and shrinkage of materials may cause more damage when it occurs in repeated cycles. As an artwork ages, its structure will become less resilient to changes, and more sensitive to its environment. Damage to artwork may result from the inadvertent, purposeful or gradual activity of water in variable quantities. Damp rooms, drips, flooding, fires and rain, are some sources for high humidity and water damage. This articleís photographs reveal an amateur remedy for repairing slack canvases by spraying the verso side of a painting with water mist. This ìrepairî can cause distortion and potentially severely damage the artwork. Controlled conservation treatment gently reverted the distortion and the visual imagery of the painting was regained. For more information about water saturation problems, visit Conservation OnLine at aic.stanford.edu
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