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Thin layers of copper micro-particles were deposited on the surfaces of Scots pine ( Pinus sylvestris L.) micro-veneers using atmospheric pressure plasma to improve the resistance of the surfaces to weathering. Three different loadings of copper were established. Micro-veneers were exposed to artificial weathering in a QUV weathering tester for 0, 24, 48, 96 and 144 h following the standard EN 927-6 [1] . Mass losses after each exposure showed significant differences between copper coated and untreated micro-veneers. Tensile strength was assessed at zero span (z-strength) and finite span (f-strength) under dry conditions (20 °C, 65% RH). During 48 h, micro-veneers lost their z-strength progressively. In contrast, copper coating at highest loading imparts a photo-protective effect to wood micro-veneers during 144 h exhibiting z-strength retention of 95%. F-strength losses were similar in all copper treated and untreated micro-veneers up to 96 h. However, after 144 h, copper coated micro-veneers at highest loading showed significantly greater strength retention of 56%, while untreated micro-veneers exhibited only 38%. Infrared spectroscopy suggested that copper coating does not stabilize lignin. Inductively Coupled Plasma revealed that micro-veneers coated with the highest loading exhibited the lowest percentage of copper loss. Blue stain resistance of copper coated Scots pine following the guidelines of EN 152 [2] was performed. Additional test with different position of the coated surface was also assessed. Copper coating reduced fungal growth when coated surface is exposed in contact with vermiculite. Spores of Aureobasidium pullulans were not able to germinate on the copper coated surface positioned uppermost.

Scots pine (Pinus sylvestris L.) sapwood specimens were subjected to a two-step treatment combining vacuum-pressure impregnation with short-chain siloxanes followed by copper deposition on the wood surface via atmospheric pressure plasma. The obtained materials were exposed to a blue stain fungus in a laboratory test following EN 152 (2011). Copper treatment alone reduced fungal colonisation, but did not fully prevent it. A two-step treatment was able to impart high resistance to Aureobasidium pullulans. Termite resistance of siloxane-treated and copper-plasma coated wood was also assessed. A laboratory no-choice test according to EN 118 (2013) revealed strong attack by Reticulitermes flavipes, but termite mortality increased compared to untreated wood. In contrast, under choice conditions, R. flavipes exhibited significant avoidance towards the treated specimens.

[EN] A laboratory no-choice test following the standard EN-117 was conducted to evaluate the efficacy of wood modified with different technologies against subterranean termites of the genus Reticulitermes spp. European beech modified with DMDHEU, acetylated radiata pine, and furfurylated Southern yellow pine were used for termite testing. Before the bioassay, half the number of the specimens (including controls) was subjected to an accelerated aging test according to EN-84. The specimens were exposed for 8 wk to the termites. Additionally, mass losses were measured. The results indicated that the feeding pressure was sufficient according to EN-117 for a valid test. Acetylated wood and DMDHEU-modified wood were classified as durable, showing excellent termite resistance. Furfurylated wood was resistant in the case of non-leached specimens; however, the leaching process led to a classification of non-durable. Thus, the new modification technologies open a real possibility of their use in the Mediterranean region as alternative preventive treatments against subterranean termites. (C) 2013 Elsevier Ltd. All rights reserved.

[EN] We investigated the effect of wax-treated and biocide-free wood specimens against three different termite species. A laboratory no-choice test with Reticulitermes banyulensis Clement was carried out in Valencia (Spain) under Mediterranean conditions for eight weeks. Scots pine sapwood (Pinus sylvestris L) fully impregnated with distinct waxes was used. Two field trials were conducted with Coptotermes acinaciformis (Froggatt) and Mastotermes darwiniensis Froggatt in northern Queensland (Australia) with wax-impregnated beech (Fagus sylvatica L) for 16 weeks. All three subterranean termites are of major economic importance in their respective regions. The results indicated that feeding pressure by the termites was sufficient within all trials for a valid test. Wax-impregnated Scots pine sapwood was classified as durable. No termites survived the test. The results showed an aging process under submersion conditions, which lead to a classification of moderately durable. The paraffin treatment showed good termite resistance under both test procedures, and was classified as durable. The Australian field trials showed a decreased mass loss of wax-treated beech, in which an amide wax showed excellent termite resistance. The results indicate a clear dependence of the termite resistance on the type and ratio of wax used and the feeding preferences of the specific termite species. (C) 2010 Elsevier Ltd. All rights reserved., The authors thank Clariant Produkte Deutschland GmbH (Gersthofen) for providing the waxes and financial support for this project.