Evaluation of the leach resistance and preservative efficacy of novel biocides as surface treatments applied by brush to spruce (Picea abies)
I M Tierney, A Bruce, D C R Sinclair, T Yeates
The comparative leach resistance and preservative efficacy of a number of alternative organic preservatives (available from Zeneca Specialties) and selected commercially available biocides as surface coatings to wood in Hazard Class 3 have been assessed. Two concentrations of test preservatives were applied by brush to Spruce (Picea abies), including formulation and untreated controls. A leaching program was carried out involving the immersion of the treated blocks in water for a scheduled period of time. Blocks were then subjected to biological tests to determine preservative efficacy using the basidiomycetes Coniophora puteana and Gloeophyllum trabeum in a modified EN 113 system; sapstain and mould tests were separately undertaken according to a modified EN 152 test using mixtures of Aureobasidium pullulans and Sclerophoma pithyophila, and Trichoderma harzianum and Trichoderma saturnisporium. Of the four alternative actives tested, one Zeneca development product based on Hexaconazole compared very favourably against the selected commercial biocides tested. An aqueous system based on a Zeneca penetrating aqueous polymer coupled with the Zeneca development active demonstrated favourable performance in relation to an existing solvent based product.
Keywords: ALTERNATIVE PRESERVATIVES; SURFACE COATINGS; LEACHING EFFICACY; BASIDIOMYCETES; SAPSTAINS; MOULDS
Conference: 98-06-14/19 Maastricht, The Low Countries