AU2021105684A4

AU2021105684A4 - Method of forming a treated timber laminate

Info

Publication number: AU2021105684A4
Application number: AU2021105684A
Authority: AU
Inventors: Mark Woodhouse
Original assignee: Woodhouse Timber Co
Current assignee: Woodhouse Timber Co
Priority date: 2021-08-17
Filing date: 2021-08-17
Publication date: 2021-10-14
Anticipated expiration: 2029-08-17

Abstract

The present invention resides in a method of forming a treated laminated timber 5 including the steps of: treating a laminate timber or components thereof with an organic solvent preservative, wherein the organic solvent preservative comprises one or more fungicides and one or more insecticides, to thereby form a treated laminated timber. The treated laminated timber alleviates some of the issues associated with prior art laminated timber. 10

Description

TITLE

Method of forming a treated timber laminate

FIELD OF THE INVENTION

[0001] The present invention relates to the field of construction. More particularly, the present invention relates to a treated timber laminate. Even more particularly, the present invention relates to method of forming a treated laminated timber.

BACKGROUND TO THE INVENTION

[0002] Any reference to background art herein is not to be construed as an admission that such art constitutes common general knowledge in Australia or elsewhere.

[0003] Insects, such as termites, can be extremely destructive to wood based materials and can compromise the structural integrity of a house or structure. Subterranean termites can work their way into the structure. Correcting these issues can be extremely expensive and disruptive.

[0004] There has been a significant reduction in logging within Australia's native forests. Consumer demand for appearance-grade hardwood joinery products - typically sourced from native forests - has grown exponentially as these materials have become an increasingly desirable feature of architectural design. As such, the cost of hardwood products has increased and the availability of hardwood products has decreased.

[0005] It will be appreciated that hardwood is becoming more and more expensive, and so replacement sources of wood would be advantageous to address the above issue. Furthermore, it would be advantageous to alleviate the problem of termites.

[0006] A presently available softwood product is thermally modified softwood products In this regard, softwood pine products are placed in a kiln and heated to 2300C. The thermally modified softwood products are only resistant to fungal decay and rot, and are still susceptible to subterranean termite attack. This thermal treatment degrades hemicellulose and eliminates resins, tannins and other extractives. The resultant product is resistant to rot and decay.

[0007] However, thermal modification typically causes the substrate to change in colour from a pale white or yellow to dark brown. This is undesirable because it limits the colours that can be applied over the modified product. As a result, many of these modified products are usually black, dark grey or brown due to this issue.

[0008] It would be advantageous to address one or more of the above issues or to provide the consumer with a useful or commercial alternative.

SUMMARY OF THE INVENTION

[0009] In one aspect, although it need not be the only or indeed the broadest aspect, the invention resides in a method of forming a treated laminated timber including the steps of:

treating a laminate timber or components thereof with an organic solvent preservative, wherein the organic solvent preservative comprises one or more fungicides and one or more insecticides,

to thereby form a treated laminated timber.

[0010] In one embodiment, the organic solvent preservative is a light organic solvent preservative.

[0011] In embodiments, the one or more fungicide is or are an azole. In certain embodiments, the azole is a triazole. In a preferred embodiment, the one or more fungicide is tebuconazole and/or propiconazole.

[0012] In one embodiment, the insecticide is permethrin, cypermethrin, deltamethrin, bifenthrin or a combination thereof.

[0013] In embodiments, the method further includes the step of applying a top coat. In one embodiment, the top coat is a primer. In one embodiment, the primer is waterproof. In an embodiment, the top coat is a waterproof primer. In another embodiment, the top coat is a water-based primer. In one embodiment, the top coat is an oil-based coating. In an embodiment, the oil-based coating is substantially clear. In one embodiment, the oil-based coating is tinted or pigmented. In some embodiments, the top coat is clear Intergrain Universal Timber Oil.

[0014] In one embodiment, the method may further include the step of applying an overcoat. The overcoat is applied on the top coat. In one embodiment, the overcoat is clear. In another embodiment, the overcoat is pigmented. The overcoat is selected based on the desired colour and appearance of the resultant treated laminate timber.

[0015] In some embodiments, the method does not include thermal treatment. In an embodiment, the thermal treatment includes treating the laminate timber to a temperature of between about 1000C and about 2500C, between about 1500C and about 2500C, between about 2000C and about 2500C, between about 2200C and about 2400C, about 2300C, or greater than about 2000C.

[0016] In some embodiments, the method further includes the step of forming a laminate timber. In one embodiment, the step of forming the laminate timber includes the step of gluing discrete pieces of timber together. In one embodiment, the discrete pieces of timber are elongate pieces of timber. In a preferred embodiment, the treatment step is completed on the laminated timber.

[0017] In a second aspect, the invention resides in a treated laminated timber formed by the method of any one of the preceding claims.

[0018] In one embodiment, the invention resides in a cladding board(s), screening and trim(s), a lining board(s), handrail component(s), door jamb(s), decking, fencing, flooring, moulding, panelling, benchtop and dowel comprising the laminated timber produced by the method of the first aspect.

[0019] The various features and embodiments of the present invention referred to in the individual sections above and in the description which follows apply, as appropriate, to other sections, mutatis mutandis. Consequently, features specified in one section may be combined with features specified in other sections as appropriate.

[0020] Further features and advantages of the present invention will become apparent from the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] To assist in understanding the invention and to enable a person skilled in the art to put the invention into practical effect, preferred embodiments of the invention will be described by way of example only with reference to the accompanying drawings, in which:

FIG 1 shows a flow diagram of forming the timber laminate;

FIG 2 shows the testing results of the timber laminate;

FIG 3 shows further testing results of the timber laminate; and

FIG 4 shows the testing results of the timber laminate.

DETAILED DESCRIPTION OF THE INVENTION

[0022] Embodiments of the present invention reside primarily in a method of forming a treated timber laminate. Accordingly, the method steps have been illustrated in concise schematic form in the drawings, showing only those specific details that are necessary for understanding the embodiments of the present invention so as to not obscure the disclosure with excessive detail that will be readily apparent to those of ordinary skill in the art having the benefit of the present description.

[0023] In this specification, adjectives such as first and second, left and right, and the like may be used solely to distinguish one element or action from another element or action without necessarily requiring or implying any actual such relationship or order.

[0024] Words such as "comprises" or "includes" are intended to define a non exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed, including elements that are inherent to such a process, method, article, or apparatus.

[0025] As used herein, the term 'about' means the amount is nominally the number following the term 'about' but the actual amount may vary from this precise number to an unimportant degree.

[0026] The present invention is predicated on the finding that the treated timber laminate produced by the present method is termite resistant. The present invention also does not require thermal modification and thus does not affect the aesthetics of the treated timber laminate. This advantageously allows for other many colours to be applied over the modified products. As such, a much larger range of pigments can be applied over the top coat to achieve the desired colour/appearance.

[0027] In one aspect, although it need not be the only or indeed the broadest aspect, the invention resides in a method of forming a treated laminated timber including the steps of:

to thereby form a treated laminated timber.

[0028] In one embodiment, the one or more fungicide is an azole. In some embodiments, the azole is a triazole. In a preferred embodiment, the azole is selected from tebuconazole and/or propiconazole. Further non-limiting examples of the fungicide include copper naphthenate, tributyl tin naphthenate and tributyl tin oxide. It will be appreciated that the above list is only an example of the fungicide and that other fungicides readily known to the person skilled in the art can be utilized with the present invention.

[0029] In one embodiment, the insecticide is a termiticide. A non-limiting example of the insecticide is permethrin, cypermethrin, deltamethrin, bifenthrin or a combination thereof. It will be appreciated that the list of insecticides are only some examples of the insecticide and that other insecticides readily known to the person skilled in the art can be utilized with the present invention.

[0030] In one embodiment, the organic solvent preservative is a light organic solvent preservative. In one embodiment, the laminated timber is treated with the organic solvent preservative. In an alternative embodiment, the discrete components of the laminate timber are treated with the organic solvent preservative prior to lamination.

[0031] In a preferred embodiment, the organic solvent preservative comprises propiconazole, tebuconazole and permethrin in a solvent. In one embodiment, the solvent is suitably water. In one embodiment, the solvent is solvent based (that is organic solvent based). In an embodiment, the solvent is methylene chloride and/or kerosene.

[0032] The organic solvent preservative suitably comprises a ratio of propiconazole : tebuconazole : permethrin of about 1:1:0.66. The organic solvent preservative suitably comprises propiconazole in an amount of between about 2 g/L and about 10 g/L, between about 3 g/L and about 7.5 g/L, between about 5 g/L and about 7.5 g/L, or about 7.5 g/L of the preservative. The organic solvent preservative suitably comprises tebuconazole in an amount of between about 2 g/L and about 10 g/L, between about 3 g/L and about 7.5 g/L, between about 5 g/L and about 7.5 g/L, or about 7.5 g/L of the preservative. The organic solvent preservative suitably comprises permethrin in an amount of between about 1 g/L and about 10 g/L, between about 2 g/L and about 7 g/L, between about 3 g/L and about 5 g/L, or about 5 g/L of the preservative.

[0033] In one embodiment, the organic solvent preservative suitably comprises propiconazole in an amount of between about 3 g/L and about 7.5 g/L, tebuconazole in an amount of between about 3 g/L and about 7.5 g/L, and permethrin in an amount of between about 2 g/L and about 5 g/L of the preservative. In a preferred embodiment, the organic solvent preservative suitably comprises propiconazole in an amount of about 7.5 g/L, tebuconazole in an amount of about 7.5 g/L, and permethrin in an amount of about 5 g/L of the preservative; the solvent making up the remainder of the preservative.

[0034] In one embodiment, the organic solvent preservative may further comprise preservative. In one embodiment, the preservative includes chrome copper arsenic, alkaline copper quaternary and/or copper azole. In one embodiment, the chrome copper arsenic comprises chrome in an amount of between about 38% and about 45%, copper in an amount of between 23% and about 25%, and arsenic in an amount of between about 30% to about 37% thereof. In one embodiment, the alkaline copper quaternary comprises copper in an amount of between about 56% and about 67%, and didecyldimethylammonium chloride or bicarbonate in an amount of between about 33% and about 44% thereof. In embodiments, the copper azole comprises copper in an amount of about 95% to about 97%, or between about 95.82% and about 96.58%; and azole (Tebuconazole and/or Propiconazole) in an amount of between about 3% and about 5%, or between about 3.42% and about 4.18%. It will be appreciated by the person skilled in the art that the above list is not exhaustive and merely represents some of the examples of preservatives that can be utilized with the present invention.

[0035] In one embodiment, the treatment step with the organic solvent preservative is loaded with the timber laminate under vacuum. The treatment step then further includes releasing the vacuum. This forces the organic solvent preservative and components thereof into the wood under atmospheric pressure. This allows the organic solvent preservative and components thereof to more effectively penetrate the timber laminate. In one embodiment, the treatment is pressurized treatment.

[0036] The method may further include the step of evaporating the residual solvent. This may simply include allowing the treated timber laminate to sit at atmospheric pressure. The active ingredients of the organic solvent preservative is impregnated into the timber laminate and protect the timber laminate from rot, fungal decay and insect attack.

[0037] In one embodiment, the method further includes the step of forming a laminate timber. In this regard, the step of forming the laminate timber includes the step of gluing discrete pieces of timber together. In one embodiment, the discrete pieces of timber are elongate pieces of timber. In a preferred embodiment, the treatment step is completed on the laminated timber.

[0038] In one embodiment, the discrete pieces of timber are treated or conditioned at a temperature at no greater than about 1000C, between about 300C and about 1000C, between about 500C and about 900C, between about 700C and about 900C, between about 750C and about 850C, or about 800C.

[0039] In a preferred embodiment, the method of forming the discrete pieces of timber includes sawing. In this regard, the step of sawing includes the grain of the timber running longitudinally along each individual piece of timber. The inventors postulate that this approach in sawing better approximates the grain patterns found in hardwood products. This allows for a more aesthetically pleasing product. This orientation produces a more aesthetically pleasing appearance. In one embodiment, the timber laminate does not comprise finger joints. The combination of the sawing and lack of finger joints leads to a particular appearance that approximates hardwood.

[0040] The present invention may further include the step of applying a top coat. In one embodiment, the top coat is a primer. In one embodiment, the primer is waterproof. In an embodiment, the top coat is a waterproof primer. The primer not only prevents the underlying treated laminated timber from absorbing solvents and/or moisture. The primer also assists in improving the waterproofing of the finish. The primer also conditions the surface such that it is compatible with a variety of finishes, such as a much larger range of pigments can be applied thereover to achieve the desired colour and appearance. The primer also allows the timber laminate to achieve a good finish with less labour.

[0041] In an embodiment, the top coat is a water-based coating. In one embodiment, the top coat is an oil-based coating. In an embodiment, the oil based coating is substantially clear. In one embodiment, the oil-based coating is tinted or pigmented. In some embodiments, the top coat is clear Intergrain Universal Timber Oil.

[0042] In one embodiment, the method may further include the step of applying an overcoat. The overcoat is applied on the top coat. In one embodiment, the overcoat is clear. In another embodiment, the overcoat is pigmented. The overcoat is selected based on the desired colour and appearance of the resultant treated laminate timber.

[0043] In one embodiment, the timber utilized in the timer laminate is softwood. In one embodiment, the timber utilized in the timber laminate is pine. In one embodiment, the pine is New Zealand Radiata pine. It will be appreciated that the above only represents some of the timbers or lumber that can be utilized in the present timber laminate, and that other timbers not expressly listed herein can be utilized with the present invention.

[0044] In one embodiment, the method does not include the step of thermal treatment. Thermal treatment includes treating the laminate timber to a temperature of between about 1000C and about 2500C, between about 1500C and about 2500C, between about 2000C and about 2500C, between about 2200C and about 2400C, greater than about 1700C, or about 2300C.

[0045] In one embodiment, the present laminate timber is resistant to subterraneantermites.

[0046] In one embodiment, the present invention meets the minimum requirements for softwood products as outlined in the follow Australian standards:

AS 1604.5:2005 - Specification for preservative treatment - Part 5: Glue laminated timber products;

AS 4785.1-2002 - Timber - Softwood - Sawn and milled products Part 1: Product specification; and

AS 5067:2003 - Timber - Non-structural glued laminated Performance and production requirements.

AS 1604.1:2021 - Preservative-treated wood based products - Part 1: Products and treatment

[0047] The treated timber is suitable for installation into a variety of interior and exterior building applications. The priming system and neutral pale colouring provides for the application of numerous translucent stain finishes and ensures that the consumer can substitute the present invention for native hardwoods.

[0048] In one aspect, the invention resides in a treated timber laminate produced by the method of the first aspect.

[0049] In one embodiment, the timber laminate can be utilized in at least cladding boards, screening and trim, lining boards, handrail components, door jambs, decking, fencing, flooring, moulding, panelling, benchtop and dowel. In one embodiment, the invention resides in a cladding board(s), screening and trim(s), a lining board(s), handrail component(s), door jamb(s), decking, fencing, flooring, moulding, panelling, benchtop and dowel comprising the laminated timber produced by the method of the first aspect.

Example Manufacturing process

[0050] The present invention can be provided by following the steps below, and shown in FIG 1:

1. providing a feedstock;

2. docking and sawing the feedstock;

3. kiln drying the feedstock;

4. laminating the feedstock;

5. profiling;

6. placing the timber laminate with an organic solvent preservative in a sealed vessel under pressure;

7. releasing the pressure in the sealed vessel; and

8. priming.

[0051] The feedstock in relation to this example manufacturing process is Radiata pine (Pinus radiata). The Radiata pine is sourced from FSC-certified plantations and sawmills in New Zealand.

[0052] Automated docking lines remove resin pockets and other visual defects from the boards. Generally, the defects in the boards are minimal because the feedstock is selected from pruned trees and logs that have had their lower branches removed during growth so that there are minimal or no knots.

[0053] The boards are then placed into a kiln and conditioned at about 800C. The boards are dried until they have an average moisture content of about 12% to about 15%. This ensures a dimensionally stable feed stock that are easily machined, profiled and will readily accept glues, preservative treatment and finishes.

[0054] The boards are then face glued with a single-component polyurethane adhesive to form blocks of laminated Radiata pine. These blocks do not contain finger-joints or any other material imperfections that might degrade the visual appearance of the final product.

[0055] The laminated timber is then broken down and run through planers to form finished profiles.

[0056] The profiled laminated timber is then loaded into a sealed treatment vessel. The organic solvent material is then loaded into the vessel during alternate cycles of vacuum pressure and releasing to atmospheric pressure. It is postulated that this forces the components of the organic solvent material into the cells of the wood. The treated laminate timber is then removed from the vessel and place in a storage area where the residual solvents are allowed to evaporate.

[0057] The profiled and treated timber laminate are then fed through a painting machine that applies a primer (such as clear Intergrain Universal Timber Oil) to each surface. The primer may be applied to each surface of the treated timber laminate at a rate of 11 000 lineal metres per hour. The resultant primed treated laminate timber is then wet-stacked.

Testing

[0058] The timber from the process was tested to ensure that there was sufficient penetration of the components of the organic solvent preservative therethrough. In this regard, criteria for treatment penetration typically requires the preservatives to be distributed throughout the penetration zone of the wood substrate. In relation to Radiata pine, the treatment typically must penetrate at least 80% of the total cross section of the product. Furthermore, the propiconazole and tebuconazole in the pine typically must be 0.06% m/m and the permethrin in the pine typically must be 0.02% m/m

[0059] Shown in FIGs 2-4 are the results of the test on the present treated timber laminate (other testing of products have been redacted). The present treated laminate are labelled sample '4 4' in FIG 2, sample '3 5' in FIG 3, and sample '1 AA721' in FIG 4. As shown, the penetration spot test was passed, and there was sufficient retention of the active ingredients.

[0060] The above description of various embodiments of the present invention is provided for purposes of description to one of ordinary skill in the related art. It is not intended to be exhaustive or to limit the invention to a single disclosed embodiment. As mentioned above, numerous alternatives and variations to the present invention will be apparent to those skilled in the art of the above teaching. Accordingly, while some alternative embodiments have been discussed specifically, other embodiments will be apparent or relatively easily developed by those of ordinary skill in the art. Accordingly, this invention is intended to embrace all alternatives, modifications and variations of the present invention that have been discussed herein, and other embodiments that fall within the spirit and scope of the above described invention.

Claims

1. A method of forming a treated laminated timber including the steps of:

to thereby form a treated laminated timber.

2. The method of claim 1, wherein the one of more fungicide is tebuconazole and/or propiconazole and wherein the insecticide is permethrin.

3. The method of claims or claim 2 further includes the step of applying a waterproof primer.

4. The method of any one of the preceding claims, wherein the method does not include thermal treatment of greater than about 2000C.

5. A treated laminated timber formed by the method of any one of the preceding claims.

FIGURES 1/4

FIG 1