Your search resulted in 679 documents. Displaying 25 entries per page.
Protection of OSB against termites by incorporation of different actives via glue line treatment
2008 - IRG/WP 08-30453
Different organic actives and zinc borate were incorporated into OSB during the manufacturing process to enhance the resistance against termites. Tests according to EN 117 revealed excellent performance of thiacloprid. Other organic actives such as permethrin might be effective when used in higher amounts. Zinc borate failed the test by far.
S Donath, P Spetmann, T Jaetsch, T Zahlmann
Bifenthrin recovery from glue-line-treated plywood
2007 - IRG/WP 07-20355
Plywood and laminated veneer lumber (LVL) can be protected from termite damage by addition of bifenthrin to the adhesive used in product manufacture. However, conditions associated with this manufacturing process may lead to deterioration or immobilisation of the active ingredient. In order to determine compliance with treatment specifications, it is important that the concentration of a preservative in the manufactured product can be accurately determined. Plywood test panels were prepared from hoop pine (Araucaria cunninghamii) veneers, using four types of adhesive; isocyanate, high alkali phenol formaldehyde (PF), low alkali PF and urea formaldehyde (UF). Bifenthrin was added to each adhesive mix to achieve three concentrations of the active ingredient in the final product. After manufacture, the concentrations of bifenthrin were determined using two sampling techniques. The concentration of bifenthrin recovered from the treated product varied with the type of adhesive used. The implications for compliance monitoring are discussed.
J Norton, L Stephens
Light organic solvent preservative treatment of glue-laminated radiata pine
1986 - IRG/WP 3380
The high permeability of radiata pine (Pinus radiata D. Don) is associated with ray-tissue and in particular the cross-field pits linking ray-tissue to tracheids. This pathway is absent in the tangential grain direction, leading to poor preservative penetration when treatment is restricted to the radial face - for example, timber fabricated into glue-laminated beams.
The performance of glue laminated railway ties after 40 years of service in the main line track
1989 - IRG/WP 2325
Two series of horizontally glue laminated ties made of a softwood body and topped with a hardwood lamination were creosoted and installed in 1947 in a tangent and a curved main line track. The tests are now 40 years old and the excellent condition of the ties of these two series suggest that a service life of 50-60 years can be expected.
J P Hösli, E E Doyle, C P Bird, T Lee
Biocide Treatments for Wood Composites - A Review
2006 - IRG/WP 06-40323
This paper reviews the biocidal treatment of wood composites. Included are in-process and post-process treatments. Various biocides are covered as are methods of application. Novel treatments and technologies are also presented.
J W Kirkpatrick, H M Barnes
Ten year field test with a copper-borate ground line treatment for poles
1993 - IRG/WP 93-30017
A wood preservative paste consisting of borax and copper naphthenate has been tested to determine its efficiency in protecting wood from decay fungi and insects. The paste was applied to polyethylene-backed wraps that were fastened to the below-ground portions of unseasoned southern pine pole stubs. After 4 years of exposure in Mississippi, the untreated control stubs were completely deteriorated. The below-grade portions of the treated stubs remained sound after nearly 6 years of exposure due to movement of copper and diffusion of the borate throughout the cross section. Borate and copper also moved vertically in the stubs and was present in sufficient amounts to protect sections of the stubs as high as 3 feet above grade. After 9 years of exposure, the below-grade portions of the treated stubs had limited areas of decay and no termite damage; the majority of the cross section remained sound. Wood analysis indicated that concentrations of borate in the sound areas were about 1/10 the estimated toxic threshold. A visual examination and push test indicated that the treated stubs continued to be protected at groundline after 10 years of exposure. It is hypothesized that the continued protection of the below-grade portions of the stubs against both decay fungi and subterranean termites is the result of copper-borate complexes that have formed in the wood.
T L Amburgey, M H Freeman
Bending creep test of plywoods under long term exposure to fungal attack
1981 - IRG/WP 2163
Bending creep test and decay test were coupled in order to evaluate the durability of structural plywoods and preservative efficacy. Experimental blocks, 5.0 x 1.2 cm² section x 35.0 cm length, were impregnated with distilled water and inoculated with mycelial fragments of test fungus. Polyethylene bags stretched with metal frame were used as decay chambers. The chambers containing inoculated blocks and water were plugged with porous silicone plugs. Weight was hanged from the center of block. The deflection at the center of span was measured with a gauge sensor connected with a recorder. The deflection due to fungal attack appeared after 800-1200 hrs incubation. Non-treated plywoods failed by 2400 hrs. Treated plywoods containing 1 kg/m³ of TBP (Tribromophenol) did not fail even after 3800 hrs but deflected continuously. When containing 5 kg/m³ of TBP, only a slight deflection was observed. Based on the assumption that decay advanced uniformly in the parallel direction to the span but wavy like as cosine curve in the perpendicular one, creep deflections were calculated and compared with the experimental ones. It may be concluded from these results that the method is promissing for evaluating the durability of structural board materials and preservative efficacy.
Remedial treatments of glulam = diffusion of active ingredients through glue lines from solid wood diffusable preservatives
1996 - IRG/WP 96-30117
Diffusable preservatives are very suitable for use in remedial treatments of laminated beams in which too high moisture content involves the development of wood destroying fungi. The diffusion of active ingredients (boric acid, disodium octoborate, bifluoride) is well observed in solid wood but in a composite wood, the glue lines may appear not only as a barrier for the diffusion but also, may be mechanically affected by the diffused active ingredients. Shear tests were carried out on glulam specimens manufactured with different types of glues: resorcine (RF), ureaformaldehyde (UF), polyurethane (PUR) and polyvinylacetate (PVAc). Diffusion tests were also carried out in accelerated wetted glulam specimens with three diffusable solid preservatives differently exposed in the test samples. Results observed with boron compounds showed that their diffusion does not affect the mechanical resistance of the beams. In another hand, interesting results were obtained concerning the passage of boron and bifluoride through some types of glues. These results will contribute to the optimization of the remedial treatment of glulams.
D Dirol, S Mouras
Remedial ground-line treatment of CCA poles in service. Results of chemical and microbiological analyses 6 months after treatment
1986 - IRG/WP 3388
CCA-treated poles in service with incipient internal soft rot were remedially treated by inserting borate rods, brushing with a boron/glycol solution and injecting boric acid paste, copper/creosote paste or a commercial product (DFCK paste). The spread of active chemicals in the treated zone as well as the change in microflora have been studied with time. After six months chemicals had spread to most parts of the pole in the ground-line zone and the microflora had been changed - in some cases drastically. The test is still in progress. Chemical and microbiological analyses after 12, 28 and 60 months will be published at a later date.
B Henningsson, H Friis-Hansen, A Käärik, M-L Edlund
Effect of alkaline phenolic resin adhesive on the stability of preservatives incorporated into the glue-line of plywood
1991 - IRG/WP 3650
Stability of preservatives was determined by gaschromatographic analysis when they were applied to glue-line treatment of plywoods. Among organophosphorous insecticides, emulsified forms of chlorpyrifos, dichlofention and diazinon were more stable than others. Fenitrothion, pyridafenthion and phoxim were not practically acceptable as emulsifieable forms due to the relatively low recovery rates after an accelerated ageing (heat exposure at 60°C after hot-press). IF-1000, an organoiodine fungicide, seemed to be less stable under the influence of heat, although the fungicide was better than the other tested organoiodine chemical (Sunplas).
S Fushiki, Y Katuzawa
Remedial ground-line treatment of CCA poles in service. A final report after 60 months' testing
1989 - IRG/WP 3534
Remedial treatment of CCA treated utility poles of Pinus sylvestris with incipient decay was carried out in 1983 and the results of chemical and microbiological analyses 6 months after treatment were reported in Document No: IRG/WP/3388 while microbiological studies 12 and 28 months after treatment as well as chemical analyses of poles treated with boron rods or boric acid paste 28 months after treatment were reported in Document No: IRG/WP/3481. 60 months after the treatment a final study was carried out on the remaining two poles left from each treatment. The study included isolations of fungi as well as chemical analyses of poles treated with boron rods, boric acid paste and borate/glycol.
B Henningsson, H Friis-Hansen, A Käärik, M-L Edlund
Test methods for wood preservatives against Lyctus: (1) Testing of treated veneer. (2) Testing of glue-line treated plywood. (Laboratory methods)
1977 - IRG/WP 293
Powder-post beetles destroy large quantities of veneer and plywood. Two test procedures are described which can be used to support application-oriented research into veneer and plywood preservatives. These procedures simulate practical conditions on a laboratory scale. Their characteristic feature is that wood species of special susceptibility are used for the tests; the susceptibility of the specimens is ensured via pre-treatment with Lyctus nutrients.
An appraisal of the vertical distribution of attack of untreated and treated wood by warm water sphaeromatids at some tropical sites - A discussion paper
1986 - IRG/WP 4124
Examples of the vertical distribution of burrows of warm water sphaeromatids relative to tide levels and mud line from sites in India, Papua New Guinea and tropical Australia are discussed in detail. These data show clearly that these animals concentrate their attack of resistant natural wood or resistant treated wood in the tidal zone, particularly around Mean Sea Level. Supportive evidence from Kenya is also presented. Circumstantial evidence indicating the repellancy of creosote to sphaeromatids is discussed together with suggested reasons why Sphaeroma terebrans Bate syn. Sphaeroma destructor Richardson was not detected in small specimen tests conducted in Australia, Papua New Guinea and at Daytona Beach, Florida whereas these borers are well known in piling timbers on tropical to warm temperate eastern Australian coasts, and were detected recently on preservative-treated piling timbers at the latter locations. It is stressed that test specimens of preservative-treated or naturally resistant wood must be exposed within the tidal zone at sites where Sphaeroma terebrans and/possibly Sphaeroma triste Heller are active, i.e. if truly meaningful measures of the resistance of such woods to these borers are to be obtained.
J E Barnacle, L J Cookson, C N McEvoy
Preservation of wood-based panels against fungi and insects and and testing its efficiency
1976 - IRG/WP 270
Wood-based panel products which are made of susceptible wood species may be destroyed by fungi under wet conditions and by termites. The glues do not provide sufficient protection unless very high concentrations are applied. Particle boards and fibre boards are not susceptible to beetle infestation, although some species may attack plywood. Various types of preservatives provide sufficient protection of panel products. These are boron, fluoride, copper, and chromium compounds in the category of water-soluble salts and various organic compounds, including contact insecticides, in the category of nonwater-soluble substances. Their application is influenced by their compatibility with the glue and by the different methods of treatment. For the production of fibreboards oil-borne preservatives are preferred. With regard to particle boards and plywood it is recommended to apply the required preservative loadings prior to the pressing operation, to mix them with the glue or to impregnate the particles or plies and with regard to fibreboards to spray the pressed and cooled down panels with the preservative. The fungus cellar test is the most suitable method for testing the efficiency of a chemical treatment of panel products against fungal attack. With regard to beetle species European standard methods of test are available. There are also laboratory and field methods for evaluating the resistance against termites. Treatment standards are controlled by chemical methods of analysis.
G Becker, M Gersonde
Remedial ground-line treatment of CCA poles in service. A progress report after 28 months' testing
1988 - IRG/WP 3481
Remedial treatments of CCA-treated poles in service with incipient soft rot were carried out with boron rods, boron/glycol solution, boric acid paste, copper/creosote paste and a commercial product (DFCK paste) respectively. The micro-flora before remedial treatment and 6 months after as well as the spread of chemicals in the poles were reported in Document No: IRG/WP/3388. In this progress report the changes in the micro-flora after 12 and 28 months are detailed together with the results of chemical studies on the spread of borates after 28 months. Studies have also been carried out on the sensitivity to borates of some fungi as well as the soft rot capacity in pine wood of some fungi isolated 28 months after treatment. The results concerning the micro-flora after 28 months are encouraging for boron rods, boron acid paste and especially for DFCK-paste. The spread of borates after 28 months was very good. In sapwood the average concentration, as boric acid, exceeded 2 kg/m³ in treated zones in poles treated with boron rods and 1.0 kg/m³ in treated zones in poles treated with boric acid paste.
B Henningsson, H Friis-Hansen, A Käärik, M-L Edlund
The efficacy of preservatives into the glue-line of plywood
1993 - IRG/WP 93-30002
This research is anti-termite/decay preservatives mixed with resin to produce the plywood. Thereafter, anti-decay/termite plywood were produced by the ordinary methods. To produce suitable plywood in the utilization and certified performance, the preservatives should be 0.3 to 0.4 kg/m³ of Chlorpyrifos; 0.88 and 1.10 kg/m³ of mix preservatives of Chlorpyrifos + IF-1000. Laboratories decay test (JWPA-regulation) and laboratories termite test (JWPA-regulation) was used. Termite field test was done in Indonesia.
S Fushiki, T Saito, Y Katuzawa, Y Imamura, S Yusuf, B Subiyanto
Future insecticidal treatments for wood products
1980 - IRG/WP 3140
Protective measures involving chemical treatment of wood use only a narrow range of toxic materials which are divisible into two groups, (i) those that are water-soluble, (ii) those that are soluble only in organic solvents. It is generally true to say that, as far as protection against insects is concerned, the former are stomach poisons while the latter are largely (though not exclusively) contact poisons (i.e., the commonly termed "insecticides"). In both groups, the most frequently used materials are currently under some pressure because of environmental considerations, but economic problems, related to supply of raw materials, also exist. In common with other organisations involved with the preservation of wood products, the N.Z. Forest Research Institute has recently put a lot of emphasis on finding new, or alternative, treating systems and this paper presents the entomological aspects of the work to date.
D J Cross
Glue-line additives for protecting plywood. A review
1978 - IRG/WP 2102
The conclusions of this review are: 1) Insecticidal glue-line additives can be used satisfactorily to protect plywood against insect attack. 2) It is uncertain, in spite of some claims, wether fungicidal glue-line additives can be similarly used to protect plywood against fungi under damp conditiones. There is a need for further work to validate the mycological tests that may be used to investigate this claims. 3) In addition, there is a need to gain experience on the in situ behaviour of glue-line additives and it is proposed that field trials be initiated to determine their ability to protect plywood over a long period.
Effect of borax-boric acid Treatment of simul (Bombax ceiba) Veneers on Glue-Bond Quality of Plywood
2010 - IRG/WP 10-40525
The glue-bond quality of plywood made of treated simul (Bombax ceiba) veneers was investigated. The veneers were treated with cold and hot water solution of borax-boric acid (BB) of different concentrations and treatment durations. The plywoods were made at three different pressures in hot press using urea formaldehyde glue. The glue-bond strength of untreated plywood in dry shear-test was found to be 2.17 and 2.29 N/mm2 made at 1.05 and 1.40 N/mm2 pressure respectively. It was observed that the values of load at failure of treated plywood in dry shear-test gradually decreased with the increasing treatment duration and concentration of solution. Comparison of the bond strength of untreated plywood with the treated ones made with urea formaldehyde glue showed that all the treatment combinations lowered the bond quality. It was also found that 10% BB solution and highest treatment duration (3 for cold water days and 60 minutes for hot water) lowered the bond strength of the plywood which met ‘B-grading’ requirement. However, the values of glue bond strength in all other BB treated plywood met ‘A-grading’ requirement for gluing. It may be due to the highest percentage of chemical deposition within the cell wall structure lowered the bond quality. For all the treatments, low values of shear strength were observed in plywood made of hot water-treated veneer compared to that of cold water.
K Akhter, Md Abul Hashem, S Akhter
Proposal for further work on accelerated ageing
1988 - IRG/WP 2314
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 the treatment of spruce. Studies of the permeability of spruce sapwood microsections to CCA preservative and to an ammoniacal solution of copper arsenate proved that the ammoniacal system penetrates 1.7 to 1.8 times faster than the CCA system, in the radial direction. The permeability in the tangential direction was on the average 3.8 times better. These results were confirmed by pressure treatments of spruce lumber and spruce roundwood with both preservatives.
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.
Field test evaluation of preservatives and treatment methods for fence posts
1985 - IRG/WP 3347
This work presents the field test results after fifteen years exposure of Eucalyptus saligna fence posts treated with six different preservatives and five treatment methods. All the combinations with oil-borne preservatives presented the best results and among the waterborne preservatives, the fence posts treated by immersion method were with the lowest performance in the field test.
G A C Lopez, E S Lepage
Manual of a mini treating plant for waterborne preservative treatment of timber and bamboo
1999 - IRG/WP 99-40130
This contributional article includes machinaries and equipments necessary for a small wood treating plant for the pressure treatment of tim bers with waterborne preservatives along with the cost and design. The preservative treatment limitations, treatment schedules and specifications for different products have been described. The cost of a mini treating plant will be 6,00,000 Tk. (13,000 US$), suitable for preserving timber and bamboo products for indoor and outdoor uses and will out last teak wood. The additional durability of timber and bamboo will create economically and environmentally safe conditions.
A K Lahiry
How to Document the Performance of Super-Critical Treated Wood in above Ground Situations?
2005 - IRG/WP 05-20316
The paper presents practical experiences from the preparation of a new preservative treated wood product for introduction to the market. The product in question is Superwood™, which is treated with organic biocides using CO2 in a supercritical state as a solvent. The question is how to evaluate the performance of a new product such as Superwood™ in order to get an acceptance on the market and fulfil the formal requirements. In the European Union countries, the EN 599-1 is the standard that needs to be complied when approving a new product for the market, but it only focuses on the toxic limit against representative decay fungi according to EN 113. However, decay test, above ground and other forms of field tests are optional, this is not in line with the traditional test philosophy in the Scandinavian countries. The open question is to which extent treatment to the level of the toxic threshold value also ensures a long service life and expected performance of the treated commodity. Superwood™ is evaluated using a strategy, in which basic laboratory tests are done to get the toxic value (according to EN 599-1) and in addition a number of field tests are done including accelerated testing in the tropics. These tests are focussed on the evaluation of the performance criteria such as durability and service life and maintenance requirements. These questions must be answered by the producer without having a full record of performance test for their new products. A short status on the test performed on super-critical treated wood (Superwood™) is presented. Based on a comparison between field test in Scandinavia and in the tropical Malaysia a service life of more than 25 years for a specific supercritical treated product is estimated. It is stated that the existing European standardisation system is insufficient when it comes to service life prediction. A number of important questions need to be addressed by the European standardisation system as soon as possible because the market and the public opinion change quickly due to environmental concern.
N Morsing, A H H Wong, F Imsgard, O Henriksen