Your search resulted in 689 documents. Displaying 25 entries per page.
Options for accelerated boron treatment: A practical review of alternatives
1985 - IRG/WP 3329
Boron wood preservatives are almost exclusively applied by momentary immersion and block diffusion storage. Alternative techniques are described which can be used to accelerate boron treatment. Diffusion coefficients have been derived to define the acceleration of diffusion with increasing temperature. Schedules are described for pressure impregnation of green timber, involving steam conditioning,...
P Vinden, T Fenton, K Nasheri
Vapour boron treatment of wood based panels: Further studies on mechanical properties
1993 - IRG/WP 93-30028
Samples of medium density fibreboard, chipboard and oriented strandboard were treated to two retentions of boric acid by vapour phase methods. The results of short term mechanical tests on this material were discussed by Hashim et al. (1992). The present paper discusses results with long term studies on bending and impact resistance with panel types. Long term tests of impact resistance showed no ...
R Hashim, R J Murphy, D J Dickinson, J Dinwoodie
Restrictions on the use of chlorosilanes as potential wood preservatives
1985 - IRG/WP 3345
The biological protection of wood by chemical modification with different types of chlorosilanes has been investigated. The impregnation of wood has been carried out by means of liquid phase and vapor phase treatments using pure silane and silane-solvent systems. The biological efficacy against wood rotting fungi, molds and staining fungi was determined in a number of screening trials, subsequentl...
M Stevens
Multiple-Phase Pressure (MPP) Process: One-stage CCA treatment and accelerated fixation process. 5. Treatment of Sitka spruce and Scots pine
1999 - IRG/WP 99-40136
The suitability of the MPP Process for CCA treatment and accelerated fixation of species other than Radiata pine was assessed by pilot plant trials on UK-grown Sitka spruce (Picea sitchensis) and Scots pine (Pinus sylvestris). Pressure and vacuum kickbacks of spruce (14 l/m3) and Scots' pine (122 l/m3) were both substantially lower than that generated during treatment of radiata pine (369...
M E Hedley, K Nasheri, G Durbin
Volatile borates in the treatment of wood and wood based panel products against subterranean termites
1995 - IRG/WP 95-30094
Blocks of pine solid wood, oriented strand board and plywood were treated with trimethyl borate by vapour treatment. It was meant to obtain either a full impregnation of the specimens or a shell treatment of the outer three millimetres. The efficacy of the treatments against subterranean termites (Reticulitermes lucifugus) was evaluated using an European Standard method....
L Nunes, D J Dickinson, R J Murphy
Combined effects of the treatment of wood with formaldehyde
1978 - IRG/WP 3117
Treatment of fibrous materials with reagents in a vapor phase is neither new nor unique. Numerous examples exist in literature of vapor phase experiments on cellulose fibers and fabrics, and on wood. For many years the textile research and industry have used vapor phase processes for the treatment of textiles. The chemical modification of cellulose is based on different types of reactions e.g. est...
M Stevens, J Schalck
Vapour boron treatment of wood based panels: Mechanism for effect upon impact resistance
1994 - IRG/WP 94-40036
Samples of medium density fibreboard, chipboard and oriented strandboard (OSB) were treated to two retentions of boric acid by a vapour phase treatment. The results of a range of mechanical tests were reported by Hashim et al. (1992, 1993) in which a small reduction in impact resistance was observed. Several investigations were carried out to study how and where this loss in impact resistance occu...
R Hashim, R J Murphy, D J Dickinson, J Dinwoodie
Treatment of wood-based panel products with volatile borate
1990 - IRG/WP 3616
The paper presents recent developments in the use of volatile borate esters for the preservative treatment of wood based board materials. Several advances on previous reports are discussed. In laboratory studies, treatment times of approximately ten minutes at 20°C on boards at equilibrium moisture content provided full penetration and retentions of 1% wt/wt boric acid. Biological tests have been...
P Turner, R J Murphy, D J Dickinson
Incorporation of phenyl boronic acid treatment with vapor phase formalization
1997 - IRG/WP 97-40083
Phenylboronic acid (PBA) treatment was incorporated with vapor phase formalization (VPF) in order to increase dimensional stability and boron fixation as well as enhancement of biological resistance. Five and ten hours VPF were applied after PBA treatment as 0.34, 0.50, 1.00 and 2.00% concs. aqueous solutions. Anti swelling efficiency (ASE) attended to 71% in specimens impregnated with 0.50% PBA s...
M K Yalinkilic, S Yusuf, T Yoshimura, W-Y Su, K Tsunoda, M Takahashi
The multi-phase pressure (MPP) process. One stage CCA treatment and accelerated fixation process
- Concepts proved by repetitive pilot plant treatments
1997 - IRG/WP 97-40079
Twenty-four charges of radiate pine roundwood or sawn timber were treated using the MPP Process and hot CCA solution. Treated timber met the CCA retention and penetration requirements of the NZ Timber Preservation Council for Hazard Classes H3 to H5. The objectives of the trials were: (1) To "stress" CCA solution by repetitive heating, treating and cooling to determine its stability in the process...
A J Pendlebury, J A Drysdale, K Nasheri, H Pearson, M E Hedley
Effect of vapour boron treatment on mechanical properties of wood based board materials
1992 - IRG/WP 92-3727
The mechanical properties of Medium density fibre board, Chipboard and Oriented strand board were investigated after treatment to two retention levels of boric acid applied as a vapour phase system. A range of mechanical properties were investigated. The vapour boron treatment does not have any significant effect on most of the mechanical properties of the boards. The exception is a reduction in i...
R Hashim, D J Dickinson, R J Murphy, J Dinwoodie
The effect of chemical treatment on the moisture distribution of Pinus radiata D.Don subjected to wick action
1999 - IRG/WP 99-40135
Radiata pine sapwood stakes were treated with a range of chemicals, including an ammoniacal copper quaternary ammonium compound (ACQ), a copper-chrome and arsenic (CCA) solution and a CCA-oil treatment, potassium linoleate copper linoleate, a paraffin wax and a proprietary alkyd resin. The effect of these treatments on the extent of water absorption and moisture movement through the stakes was inv...
J Hann, P Vinden
The multi-phase pressure (MPP) process. One-stage CCA treatment and accelerated fixation process
- The process as a new concept in preservative treatment
1997 - IRG/WP 97-40078
The background to current commercial CCA treatment schedules used in New Zealand and fixation processing is reviewed. The limitations of these conventional practices with respect to treated product quality and CCA solution handling issues are defined. A novel, patented treatment schedule has been developed using a combination of hydraulic and pneumatic pressure phases and hot (~ 75°C) CCA solutio...
K Nasheri, A J Pendlebury, J A Drysdale, H Pearson, M E Hedley
Multiple-Phase Pressure (MPP) Process: One-stage CCA treatment and accelerated fixation process. 4. MPP compared with other processes for achieving acceptable treatment of radiata pine heartwood
1998 - IRG/WP 98-40115
Although radiata pine sapwood is very amenable to preservative treatment, it is often difficult to achieve the required standard for heartwood treatment.
A preliminary investigation showed that to achieve the NZ Timber Preservation Council minimum penetration requirements for radiata pine heartwood using the Multiple-Phase Pressure (MPP) Process, a hydraulic pressure of at least 1250 kPa for 20 m...
K Nasheri, J A Drysdale, G Durbin, M E Hedley
Treatment of wood with boron esters
1995 - IRG/WP 95-30087
The treatment of wood and wood products with boron esters is reviewed. The physical and chemical characteristics of boron esters affecting the treatability of wood are discussed, in particular thermal decomposition and rates of hydrolysis. The uses and methods applying boron esters as wood preservatives include: (i) Solutions of boron esters for remedial and diffusible treatment of wood; (ii) soli...
J Romero, P Vinden, J A Drysdale
Gaseous preservative treatment of wood
1990 - IRG/WP 3631
A recent development in processing wood with a gaseous preservative means that dry, treated wood can be produced in under 30 hours with the benefits of product diversification, faster stock turnover and the ability to respond to short term demand. About 400,000 m³ of wood are treated each year in New Zealand with boron salts to protect from borer infestation. Traditionally this treatment is effec...
R Burton, A J Bergervoet, K Nasheri, P Vinden, D R Page
Redistribution of boric acid in radiata pine during drying after preservative treatment
1993 - IRG/WP 93-40010
Samples of 100 x 50 mm² radiata pine were processed with a variety of options to produce dry, boron-treated wood. Concentrations of boric acid in the central one-ninth and in the whole of the wood cross-sections were determined by chemical analysis and compared. Diffusion treated material was dried by air, conventional kiln (70/60°C), or high temperature kiln (120/70°C). Four different predryin...
A J Bergervoet, D R Page, J A Drysdale
Multiple-Phase Pressure (MPP) Process: One-stage CCA treatment and accelerated fixation process. 3. Effect of process variables on sapwood treatment and CCA fixation.
1998 - IRG/WP 98-40114
The Multiple-Phase Pressure (MPP) Process achieves treatment and fixation as combined process using hot CCA, within a 2-3 hour time-frame. Timber is treated to saturation with hot CCA using an empty cell process. During the pneumatic pressure phase, hot solution is held in the wood in an otherwise liquid-free treatment vessel until fixation is >95% complete.
This report details a factorial des...
H Pearson, K Nasheri, J A Drysdale, G Durbin, M E Hedley
Survey of North American practice in conditioning forest products before preservative treatment
1972 - IRG/WP 308
Seasoning requirements for the wide range of forest products which are treated with preservatives and fire retardants must be capable of dealing with a very complex set of conditions which are summarized under a number of variables including type and hazard of end use, the most effective distribution of preservative, a wide range of cross sectional dimensions, the possibility of seasoning by a ran...
J Rak, T S McKnight
Survey of practical methods for conditioning of forest products before preservative treatment
1971 - IRG/WP 39
The seasoning of forest products is undertaken for a wide range of end uses and is becoming increasingly required for applications and building construction and secondary manufacturing industries. A wide range of applications of new technology and specifically required seasoning schedules is being actively developed for such requirements, but less attention has been given to the means by which woo...
J Rak, T S McKnight
Development of preservative treatment method using sub and super critical carbon dioxide
2007 - IRG/WP 07-40385
Significant efforts have been devoted for developing biocide impregnation method into wood materials using supercritical fluid. Developing better understandings of fluid phase and its effect on treatment results would facilitate a more rational development of supercritical fluid (SCF) impregnation. In this project, the preservative treatabilities under super- and sub-critical fluid conditions we...
Myeung-Won Cho, Sung-Mo Kang, Gyu-Hyeok Kim
Experiences with an industrial system for controlled thermal wood modification in pressurized unsaturated steam
2014 - IRG/WP 14-40678
Thermal wood modification in pressurized reactors has a long history, but these processes are to date industrially scarcely used, because of the relatively complicated process equipment, compared to the more common high-temperature processes in kilns at atmospheric pressure. However, based on our practical experience with the FirmoLin® process, supported by recent scientific findings, it is foun...
W Willems
Proposal for further work on accelerated ageing
1988 - IRG/WP 2314
M-L Edlund
Status of the research and development of a new preservative system (EFPL) for pressure treatment of spruce in Canada
1975 - IRG/WP 348
Our work has been to develop a system which would have the stability of the ACA system and the formulation flexibility of the CCA system enabling properties such as fixation of arsenic, water repellency, appearance and cost to be controlled. Our permeability studies of spruce using a method previously developed indicated that an ammoniacal solution of copper arsenate is an excellent candidate for ...
J Rak, M R Clarke
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 2: Report of treatment and installation in Australia
1978 - IRG/WP 440
The purpose of this test and the procedures to be followed have been fully set out in documents distributed by the International Research Group on Wood Preservation and numbered IRG/WP/414 and IRG/WP/420. The prescriptions set out in these two documents have been closely followed....
J Beesley