In the conservation of wooden artifacts, it is often necessary to repair broken wooden elements which serve a structural or load-bearing function. Such repairs must have high strength, yet be reversible in the future. Where the break in question is recent and the mating surfaces are clean and undisrupted, animal hide glue is widely accepted to be a suitable adhesive, though in practice, reversal of intact hide
glue bonds can be problematic. In cases where the mating surfaces are dirty, damaged, or a gap filling adhesive is needed, animal hide glue may have greatly reduced strength and an alternative adhesive may be required. Bulked epoxy resins have found wide use in such instances, and some have the additional advantage that after setting they can be carved, sawn, sanded, and finished, allowing them to be used simultaneously as both adhesive and fill material. One commercially available product of this sort which is widely used by furniture conservators is Araldite 1253, a carvable paste epoxy, bulked with titanium dioxide, amorphous silica, iron oxide, and phenolic resin (Ciba, 2001). The primary disadvantage of using epoxies in conservation is that, once cured, they can be extremely difficult to reverse.
Barrier coatings are widely used in conservation to add a measure of reversibility to an otherwise irreversible adhesive bond.
Pages : 12
Size: 509 kb
Author :Lisa Ellis and Arlen Heginbotham
An Evaluation of Four Barrier Coating and Epoxy Combinations in the Structural Repair of Wooden Objects