Your search resulted in 563 documents. Displaying 25 entries per page.
Contradiction between uptake of preservative in practical situation and laboratory testing
1992 - IRG/WP 92-2392
By brush treatment water- and solvent-based products were applied on boards of Scots pine and Norway spruce to achieve an uptake of 100 and 200 g/ml. In addition the scope of work to achieve the required uptake of preservative was determined under practical conditions for both product groups. EN 113 (RAL-GZ 830) tests were carried out to test the biological efficacy of products. After 18 months ex...
R Gründlinger, O Janotta, M Melzer
Application of roller-pressing method to the novel liquid impregnation treatment of green timber
2001 - IRG/WP 01-40198
A transverse compression technique enabled us to impregnate liquid into green timber through replacement of the free water in the timber with a treatment liquid without any critical physical damage to the timber by the roller-pressing method. The roller-pressing is supposed to remove free water the cell cavities and to concurrently introduce the treatment solution into green timber in the treatmen...
M Inoue, K Adachi, K Tsunoda, Y Imamura, S Kawai
Selective chromate elimination from the storage-drainage-water of a wood impregnation plant
1980 - IRG/WP 3153
With the Enviro-Chrom-Ex process it is possible to eliminate ecologically and economically hexavalent chromium (chromate) from water selectively. The process which is based on the principle of selective ion exchange works with different chromate concentrations and under the presence of other ions, irrespective of the water hardness. The values of water-offtake reach 0.1 mg CrVI at maximum, causing...
O Wälchli, R Ott, R Hugener, E Graf, B Lieberherr
The non-uniform uptake of chromium and copper during the impregnation of wood using the example of a CCB-salt
1998 - IRG/WP 98-20137
The correct impregnation of wood requires among other things a regular control of the concentration of the treating solution as this and/or its stoichometric composition can change as a result of the impregna-tion process and the treated wood. The preferential uptake of individual wood preservative components by the wood is of particular importance in this connection.
Dipping and vacuum impregnat...
P Jüngel, E Melcher, R-D Peek
A novel solvent penetration assessment technique for wood preservativation treatments using waterborne systems
1990 - IRG/WP 2346
Solvent and hence solute (a.i.) penetration during any wood preservation treatment cycle and the flow pathways taken by the solvent in the wood are crucial elements in determining the adequacy of any treatment. Inadequate solvent penetration into specimens or an inappropriate tissue throughflow pattern during impregnation will markedly affect the distribution pattern achieved by many non-diffusibl...
A J Pendlebury, J Coetzee, E Sorfa, A Botha
Treatment of poplar plywood with solvent and water-borne preservatives
1989 - IRG/WP 3538
Poplar as a light hardwood is appropriate for plywood production. Owing to its low natural durability it is generally recommended to preserve it in all conditions where risks of fungal attack may be present. A research project has been carried out on preservative treatments of plywood commodities. Parameters studied were various treatment cycles, three types of plywood, and a number of solvent and...
J Van Acker, M Stevens
Acceleration of boric acid uptake into the subterranean termite, Coptotermes formosanus Shiraki using steamed larch wood
2000 - IRG/WP 00-10353
Laboratory tests were done to measure the efficacy of addition of steamed larch (Larix leptolepis (Sieb. et Zucc.) Gord.) heartwood extracts for the uptake of boric acid against the termite, Coptotermes formosanus Shiraki. Paper discs were treated with the water-soluble fraction obtained from hot-water extracts of steamed larch wood (S-Water) with or without 0.01-2.0% boric acid, followed by expos...
W Ohmura, S Doi, S Ohara
Water repellency of wood treated with alkylammonium compounds and chromated copper arsenate
2000 - IRG/WP 00-30231
The comparative water sorption properties of southern pine treated with CCA and several alkylammonium compounds was evaluated for freshly treated wood and for wood after exposure in a fungus cellar. It was found that CCA imparts considerable water repellency to wood which is reduced somewhat after exposure to wet soil. With the exception of a long chain (C20 -C22) compound, the alkylammonium compo...
D D Nicholas, A Kabir, A D Williams, A F Preston
Interactions between water-borne preservatives and emulsion additives that influence the water repellency of wood
1991 - IRG/WP 2374
Incorporation of non-polar additives into water-borne treatments through of emulsion technology can greatly improve the physical characteristics of wood in service. Of specific interest with these emulsions is their effectiveness in reducing the rate of wood swelling. We have observed that the presence or absence of preservatives can often significantly influence the resultant effectiveness of the...
A R Zahora
Influences of the hydro-thermal treatment on physical properties of beech wood (Fagus orientalis)
2005 - IRG/WP 05-40303
Influences of the hydro-thermal treatment on physical properties of beech wood were studied. Wood specimens (2×2×2cm) were treated in two steps. At first step, samples were treated at 160,180 & 200ºC for 4, 5 & 6 hours. At second step, treated samples were cured based on their first step treatment temperatures (160,180 & 200ºC) for 16 hours. The treated samples were soaked in water...
B Mohebby, I Sanaei
Accelerated diffusion treatment of sawn Sitka spruce grown in the UK
1986 - IRG/WP 3395
The treatment of 'green' sapwood and heartwood of Sitka spruce by diffusion methods was investigated. Steam/dip treatment processes gave increased solution uptakes and depths of penetration of copper in comparison with a simple dip treatment. Further investigation is required to reduce diffusion gradients with copper based formulations and to improve the penetration of '...
R J Murphy, D J Dickinson
Improvement in dimensional stability against water of the main Spanish timbers impregnated with water repellent organic protectors
1988 - IRG/WP 3468
The study reported the increase of dimensional stability against water of the main Spanish timbers, both broadleaved and coniferous, after impregnation in the autoclave with organic protector, with contains 33.3% water repellent waxes and resins. The proposed Spanish standard, U.N.E. n° 56541 is used, where dimensional stability of the impregnated wood is expressed as a% of that of the non-impreg...
J A Rodríguez Barreal
New principles for the protection of wood: Impregnation with waterborne resins
1995 - IRG/WP 95-40047
The environmental impact of classical wood preservatives as well as the use of tropical wood species with high natural durability is regarded increasingly critically in the public. Therefore other partially new principles for the protection of wood, like chemical modification, or treatment with resins were examined especially in USA, Japan and in Europe with promising results predominantly in the ...
A O Rapp, R-D Peek
CCFZ, a new type of water-borne wood preservative for vacuum pressure impregnation
1991 - IRG/WP 3643
By combination of CCF-Salt types with zinchexafluorosilicate a remarkable improvement of efficacy is achieved. In the same time the ecotoxicoligical data become more save. As well as the efficacy against wood-destroying organisms (Basidiomycetes, Soft rot and Long horn beetle) the basic data to evaluate the ecotoxicological behaviour of a CCFZ-Salt are described and compared with the properties of...
W Metzner, D Seepe, H-W Wegen
Microdistribution of water-borne preservatives in blue gum treated by full-cell process
1990 - IRG/WP 3617
The present work deals with the study of the microdistribution of copper, chrome and arsenic elements in Eucalyptus globulus Labill. sapwood, treated with a CCA water-borne preservative by full-cell process, with the help of scanning electron microscopy together with energy dispersion X-ray analysis technique. The work shows that the retention of CCA elements is high in vessels and vasicentric par...
D De Sousa Castro Reimão, J M Palacios
A substantively bonded water repellent treatment based on chromium carboxylates
1985 - IRG/WP 3344
Chromium carboxylates soluble in toluene have been synthesised and applied to Scots pine (Pinus sylvestris) sapwood. Without any further treatment, the compounds may be readily leached from wood surfaces with toluene. After a period of heating however, they become fixed to the cell wall, substantial amounts being resistant to leaching even under reflux conditions for several hours. Treatment of wo...
J K Wright, W B Banks, W J Eilbeck
The potential of high pressure pulsation processes to treat white spruce lumber with water-borne preservatives
1988 - IRG/WP 3471
Laboratory work using end sealed 4x8x46 cm³ white spruce samples has been done to explore the suitability of three variants of a 2.1 MPa pulsation process for the impregnation of white spruce with CCA. The results showed that the process improved significantly the penetration of the preservatives and reduced significantly cell collapse, when compared with the results of treatment using a 2.1 MPa ...
J P Hösli, J N R Ruddick
Factors affecting the resistance of fibre building boards to fungal attack
1975 - IRG/WP 252
Fungal decay is initiated at lower moisture contents in standard and tempered hardboards (18%) than in pine sapwood (26%). In contrast, in a saturated atmosphere, the equilibrium moisture contents of standard hardboard (14%) and of tempered hardboard (12.5%) are much lower than the moisture content permitting decay initiation whilst the equilibrium moisture content of pine sapwood (25.1%) approach...
C Grant, J G Savory
Hydrophobic characteristics of pyrolysis oil
2008 - IRG/WP 08-30458
Hydrophobic behavior of pyrolysis oils obtained by pyrolysis of Scots pine wood (Pinus sylvestris L.) by using extruder type pyrolyzer at 450, 550 and 600 ºC was the objective of the study. Sapwood specimens (15×25×50 mm along the grain) were impregnated with the obtained pyrolysis oils by full- and empty cell treatment.
The results indicated that wood impregnated with the studied pyrolysis o...
A Temiz, M Hakki Alma, N Terziev
The effect of gamma radiation on selected wood properties
2008 - IRG/WP 08-40394
As an easy, fast, and effective sterilisation method, gamma irradiation changes molecular structures not only in pest’s living cells, but also in wooden cell walls. Radiation-induced depolymerisation causes significant changes in some properties of wood crucial for restoration and for laboratory testing of wood-preservative effectiveness. The influence of gamma radiation concerning total amount ...
R Despot, M Hasan, A O Rapp, C Brischke, C R Welzbacher
Preliminary investigation of biological resistance, water absorption and swelling of thermally compressed pine wood panels
2008 - IRG/WP 08-40396
Wood can be modified by compressive, thermal and chemical treatments. Compression of wood under thermal conditions is resulted in densification of wood. This study evaluated decay and termite resistance of thermally compressed pine wood panels at either 5 or 7 MPa and at either 120 or 150?C for one hour. The process caused increases in density and decreases in thickness of the panels; however, lab...
Ö Ünsal, S N Kartal, Z Candan, R Arango, C A Clausen, F Green III
Evaluation of Water Repellency of Treated Wood Using Several Alternative Methods
2009 - IRG/WP 09-20419
In this study, the results of water repellency testing using a digital swellometer method for water-borne organic-preservative systems with water repellent additives are reported. The findings suggest that the traditional method of using matched untreated controls as a reference developed from historic solvent-based treatments for determination anti-swelling efficacy (ASE) may underestimate the a...
L Jin, A F Preston
Comparative Study of Heat Treatment of Beech Wood in Hot Water and Steam Medium
2010 - IRG/WP 10-40536
Heat treatment of wood is an effective method to improve the dimensional stability and durability against biodegradation. Heat treatments of beech wood in 2 different mediums (hot water and steam) in 180ºC were compared in physical, mechanical and anatomical properties. Mass loss in hydrothermally treated wood was higher than hygrothermally treated samples. Mechanical properties (MOR, MOE and CS)...
A Talaei, K Yaghoobi, A N Karimi
Influence of wood swelling agents on penetration and copper leaching of copper-ethanolamine based wood preservatives
2011 - IRG/WP 11-30556
Copper ethanolamine based preservatives are currently the most important solutions for impregnation of wood in ground contact in Europe. One of the issues related to those and similar water based solutions is insufficient penetration to refractory wood species like Norway spruce. In order to elucidate this issue, commercial copper ethanolamine based solution was supplemented with five different wo...
M Humar, N Thaler, B Lesar
Evaluation of an optimized industrial process aiming to improve the natural durability and mechanical behavior of bamboo for outdoor use
2011 - IRG/WP 11-40554
Mao Bamboo (Phyllostachys pubescens) is characterized by high contents of sugar and starch and by high hygroscopicity, which makes it susceptible to biodegradation, and specifically to fungal decay. Still, many bamboo based products regularly enter the European wood construction market, competing with traditional solid wood products used for outdoor decking and cladding. The performance of a heat ...
F Simon, M Kutnik, I Le Bayon, G Moisset, V Gatimel