COMPOSITE BOARD Field of the Invention The present invention relates generally to the art of wood. More particularly, it concerns a new composite board and a process for making the same. Background of the invention: Wood is a common material used in residential, commercial, and industrial constructions as structural panels, cabinets, and door components as well as other functions. Even today, after the development of many new types of materials, wood remains one of the most widely-used structural materials because of its excellent strength and stiffness, pleasing aesthetics, good insulation properties and easy workability. However, in recent years the cost of solid timber wood has increased dramatically as its supply shrinks due to the gradual depletion of old-growth and virgin forests. Accordingly, because of both the cost of high-grade solid wood as well as a heightened emphasis on conserving natural resources, wood-based alternatives to natural solid wood lumber have been developed that make more efficient use of harvested wood and reduce the amount of wood discarded as scrap. Plywood, particle board, laminated veneer lumber (LVL) and oriented strand board ("OSB") are examples of wood-based composite alternatives to natural solid wood lumber that have replaced natural solid wood lumber in many structural applications in the last seventy-five years. Hardboard is a composite product that is made by compressing shredded wood chips together under very high pressure and usually at high temperature with a binder. Sometimes the hardboard is tempered for increased surface hardness, and usually hardboard has a thickness which is in the range of about 6 to 9 millimeters. Hardboard has a high strength and high surface smoothness. Fiberboard is a composite board which is made by compressing fibers, as opposed to discrete chips or particles, together under high temperature and pressure in the presence of a binder. Fiberboard has a somewhat less particulate appearance than
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hardboard, but can be formed with extreme surface hardness and is usually relatively smooth. Particleboard, sometimes also referred to as chipboard, is made from discrete particles or chips of wood as is hardboard. Usually the chips are somewhat coarser than hardboard and are held together by a binder during curing which is at lower temperatures and pressures than hardboard. Particleboard is less dense, has greater surface roughness, and has a greater variation in the hardness of the surface due to the larger chip sizes and lower density of the board. Particleboard, however, often comes is very thick sections and can take a wide variety of forms other than sheets or panels. In the past such engineered board have been specified for various applications, however the majority are either used structurally, or as inexpensive lining, or bases for other surface finishes. They are not generally valued, left exposed, or specified as a finished decorative product. There is still a need for a composite board that combines aesthetic qualities with appropriate strength, workability, durability and versatility characteristics. The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge. Summary of the invention: In a first aspect of the invention, there is provided a composite board comprising wood strips and a binder wherein the wood optionally comprises one or more of virgin wood, recycled wood, Oriented Strand Board (OSB), Wafer Board, Strand Board, Smartply, Sterling Board, Wood Structured Panel, Hard Board, Fibre Board, Particle Board, Laminated Veneer Lumber (LVL ) or any other suitable engineered wood. In a second aspect of the invention, there is provided a composite board comprising wood strips and a binder, the composite board having at least one of the following characteristics: a density greater than 550 units and preferable greater than 660 units; an internal bond greater than 0.3 Mpa and preferable greater than 0.6 Mpa; 2 a modulus of elasticity which is at least 3 times that of particle board and preferable at least 4 times that of particle board; a modulus of rupture which is greater than particle board; a low formaldehyde emission level, and preferably one which meets the Japanese F rating; a high surface soundness and preferable one which is higher that particle board; a high wet bend strength and preferably one which is higher than particle board; and a moisture content which within 10% of particle board. In a third aspect of the invention, there is provided a process for making a composite board, the process comprising the steps of: a) providing elongated pieces of wood each optionally comprising one or more of virgin wood, recycled wood, Oriented Strand Board (OSB), Wafer Board, Strand Board, Smartply, Sterling Board, Wood Structured Panel, Hard Board, Fibre Board, Laminated Veneer Lumber (LVL ) Particle Board. b) detecting an average fiber density of each of the pieces of wood; c) selecting among the pieces of wood those suitable for inclusion in the board according to one or more set criteria; d) planing off edges of the pieces of wood selected in step c); and e) bonding side by side the pieces of wood planed off in step d) by means of their edges to form the composite board. Throughout this specification (including any claims which follow), unless the context requires otherwise, the word 'comprise', and variations such as 'comprises' and 'comprising', will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps. 3 Brief description of the Figures: Figure 1 is an example of a composite board according to the present invention which comprises OSB. Detailed description of exemplary embodiments: It is convenient to describe the invention herein in relation to particularly preferred embodiments. However, the invention is applicable to a wide range of situations and it is to be appreciated that other constructions and arrangements are also considered as falling within the scope of the invention. Various modifications, alterations, variations and or additions to the construction and arrangements described herein are also considered as falling within the ambit and scope of the present invention. The composite board of the invention is an engineered wood product. It has a unique finish and texture and can be used for a broad range of applications. It may comprise any suitable new or recycled wood product. In some preferred embodiments it comprises one or more of virgin wood, Oriented Strand Board (OSB), Wafer Board, Strand Board, Smartply, Sterling Board, Wood Structured Panel, Hard Board, Fibre Board, Laminated Veneer Lumber (LVL ) Particle Board or any other suitable engineered wood. In one preferred embodiment it comprises Oriented Strand Board and / or Laminated Veneer Lumber (LVL ) In some embodiments, the composite board of the invention comprises recycled boards which may for example be classed as post consumer waste. As an illustrator, the typical origin of this OSB is it may have been made from reclaimed boards once used to build large industrial crates, to ship heavy duty machinery. These original boards were made from post industrial shavings of rare and common timbers, from discarded off cuts, at timber processing mills around the world. After the crates were discarded and sent to the salvage yard, they are reclaimed and re-constituted to achieve the current form. In another example, timber logs are processed at mills with off cuts discarded as waste. This Post Industrial timber waste from mills is made into a suitable engineered board, such as OSB. This timber is then made into a consumer product such as crates. After use, this product is disposed as Post Consumer waste. This waste may for example then be re-constituted into a composite board according to the invention and then into another consumer product such as joinery, furniture, wall panelling, flooring, benches 4 plus others. When this second consumer product is disposed as waste, the timber can be still be further processed into particle board or used for varied applications including landscaping, outdoor furniture, buildings etc. It is rare for any timber or other consumer product to be able to be recycled so many times and still provide structural integrity as well as, reducing the need for virgin timber. However, composite boards according to the invention are highly valued as an environmentally preferred timber. The composite board of the invention is also of great interest to architects and designers for commercial Green Star rated building projects. Being a recycled timber, it would rate highly by bodies such as the GBCA (Green Building Council of Australia) under the MATERIALS CATEGORY - MAT -8 category for Green Star - office Design V2. There would also be possible additional points available under the INNOVATION CATEGORY - INN-3. Laminated Veneer Lumber (LVL) may be manufactured from thin veneers that are rotary peeled or sliced, dried and laminated together (staggered joints) under heat and pressure with a structural adhesive (eg. phenolic based) to form a solid member. The grain on each ply is usually oriented in the same direction as the length of the member. LVL can be manufactured from most softwoods and many hardwoods, and are on average 50% stiffer and 2-3 times stronger than the sawn timber from which it is manufactured. LVL may be manufactured as pressed billets ranging in thickness from 9mm to 120mm. Such billets may be ripped into strips between 36mm and 1200mm wide to form lineal wood components. The product may be coated with a clear or coloured water based micro-emulsion water repellent. In some embodiments, the LVL used comprises one or more of a specific gravity in the range 0.40 to 1.00 and optionally 0.50 - 1.00; an auto-ignition temperature of greater than 220 degrees Celsius; comprises wood veneer (>92%), phenol formaldehyde resin (< 8%), water based emulsion with colour pigments (<0.01%), lead free organic (<0.03%). In one embodiment of the invention, depicted in Figure 1 in which a composite board of the invention is manufactured from recycled OSB or optionally LVL, the steps of manufacture comprise: 1. Removing nails and other metal from the timber. 2. Dressing and cleaning with a thicknesser or panel planer. 3. Cutting the board into strips approximately 2 mm wider than the required finished thickness. 5 4. Abutting timber strips, for example horizontally and laying them out to a required thickness, width and length. (To achieve finished lengths longer than the original board, lay up cut lengths in a brick pattern.) 5. Using a docking saw to cut strips to the required length and insert if required to slightly extend past these dimensions. 6. Applying adhesive using for example a glue spreader to all abutting edges. Any suitable adhesive may be used, for example it may be water based (such as PVA) or it may equally be non-water based, for example Phenolic low formaldehyde adhesive. 7. Laying up (for example in clamps or a press, such as a wind mill press, for example by using a bar claim in the horizontal. 8. Using a pipe clamp to reduce the gaps between the timber sections with pressure. 9. Using a wide belt sander to process the board until the desired thickness is achieved. 10. Use an appropriate adhesive to provide structural integrity. For example, a polyvinyl alcohol (PVA) or other water based adhesive for an inside application and a phemolic or low formaldehyde adhesive for water resistant applications. In some embodiments, the process to manufacture a composite board according to the present invention may comprise the following steps: 1. reception of the dry raw material; 2. stock piling the raw material; 3. feeding the raw material to the mill; 4. selection of appropriate pieces of wood based on structural, quality and / or aesthetic qualities; 5. detecting and eliminating any defect present in each piece of wood; 6. profiling the end joints; 7. applying the glue on the profiles made; 8. end jointing the pieces of wood and pressing the joints to form lamellae of wood; 9. hardening of the glue joints; 10. precision planing off of the lamellae; 11. application of glue on the edges of the lamellae; 12. edge bending the lamellae and pressing the lamellae to form a wood board; 6 13. hardening of the edge joints of the board; 14. trimming sides of the board to a desired width; 15. precision planing off of the board; 16. trimming ends of the board with precision; 17. piling and wrapping of the final product; 18. stocking the final product; and or used for varied applications including landscaping, flooring, outdoor furniture buildings etc. 19. shipping the final product to the client. Composite boards according to the present invention may also comprise strands from any suitable wood species including naturally occurring woods such as bamboo, hardwood or softwood species, singularly or mixed, whether such wood is dry (for example having a moisture content of between 2 wt % and 12 wt %) or green (for example having a moisture content of between 30 wt % and 200 wt %). Suitable wood species might for example comprise balsam fir, pine species such as Loblolly pine, Virginia Pine, slash pine, Short leaf pine, and long leaf pines, as well as Aspen or other hardwood species similar to Aspen. In some embodiments, the raw wood starting materials, either virgin or reclaimed, are cut into strands, wafers or flakes of desired size and shape, which are well known to one of ordinary skill in the art. The strands in some embodiments may for example be more than 5 cm long, more than 1cm wide, and less than 7.5 mm thick. While not intended to be limited by theory, it is believed that longer strands, i.e., longer than about 18 cm, improve the final product mechanical strength by permitting better alignment. It is also known that uniform-width strands are preferred for better product quality. Uniform strand geometry allows a manufacturer to optimize the manufacturer's process for a particular strand size selected. For instance, if all the strands were 12 cmx 3 cm, then the orienter could be optimized to align those strands within a single layer. If strands that were 3 cm long and 7.5mm wide were added, some of those could slide thru the orienters sideways. Cross-oriented strands lower the overall mechanical strength/stiffness of the product. In some embodiments, after the strands are cut they may be dried in an oven to a moisture content of about 1 to 20%, preferably between 2 to 18%, more preferably from 7 3 to about 15%, and then coated with one or more polymeric thermosetting binder resins, waxes or other additives. The binder resin and the other various additives that are applied to the wood materials are referred to herein as a coating, even though the binder and additives may be in the form of small particles, such as atomized particles or solid particles, which do not form a continuous coating upon the wood material. Conventionally, the binder, wax and any other additives may be applied to the wood materials by one or more spraying, blending or mixing techniques, a preferred technique is to spray the wax, resin and other additives upon the wood strands as the strands are tumbled in a drum blender. In some embodiments being coated and treated with the desired coating and treatment chemicals, these coated strands are used to form a multi-layered mat. In a conventional process for forming a multi-layered mat, the coated wood materials are spread on a conveyor belt in a series of two or more, preferably three layers. The strands are positioned on the conveyor belt as alternating layers where the "strands" in adjacent layers are oriented generally perpendicular to each other. It is understood by those skilled in the art that the products made from this process could have the strands aligned all in the same direction or randomly without a particular alignment. Various polymeric resins, preferably thermosetting resins, may be employed as binders or adhesives according to the present invention. Thus for example in some embodiments, suitable polymeric binders include isocyanate resin, urea-formaldehyde, phenol formaldehyde, melamine formaldehyde ("MUF") and the co-polymers thereof. Isocyanates are the preferred binders, and preferably the isocyanates are selected from the diphenylmethane-p,p'-diisocyanate group of polymers, which have NCO- functional groups that can react with other organic groups to form polymer groups such as polyurea, -NCON-, and polyurethane, -NCOO-. 4,4-diphenyl-methane diisocyanate ("MDI") is preferred. A suitable commercial pMDI product is Rubinate 1840 available from Huntsman, Salt Lake City, Utah, and Mondur 541 pMDI available from Bayer Corporation, North America, of Pittsburgh, Pa. Suitable commercial MUF binders are the LS 2358 and LS 2250 products from the Dynea corporation, Helsinki, Finland. The binder concentration is preferably in the range of about 1.5 wt % to about 20 wt %, more preferably about 2 wt % to about 10 wt %. A wax additive may be employed to enhance the resistance of the composite board to moisture penetration. Preferred waxes are slack wax or an emulsion wax. The wax loading level is preferably in the range of about 0.5 to about 2.5 wt %. 8 Composite boards according to the invention have a variety of attractive surface designs and textures available. Each design varies depending on the original design and the timber species used in the raw materials (such as OSB as depicted in Figure 1). This unique, highly decorative board can be specified for residential and commercial applications. The timber surface can be left raw, stained, oiled, or waxed as required. The density of the timber in certain embodiments, such as for example those comprising OSB, provides a strong durable surface, allowing this product to be installed in hard wearing areas. Surprisingly, the density of certain embodiments of the invention is comparable to hardwoods. Composite boards according to the invention may also be used as a veneer. Any suitable thickness may be used. In some embodiments, the veneer is between 1 mm and 500mm thick. In some preferred embodiments, it is between 10 mm and 200 mm thick. However, it should be understood that a composite board according to the present invention may have other dimensions than the ones above without departing from the scope of the present invention. Composite boards of the current invention can be used in a wide variety of applications, for example, wall panelling, floors, bench tops, joinery, furniture exposed structural beams or any suitable wood application which may have an aesthetic element to it. In some embodiments, the unique textured, solid timber surface of composite boards of the invention provide useful options to solid timbers and thus further reducing the demand for rare, exotic and threatened virgin timbers. An advantage of composite boards of certain embodiments is that dense exposed timbers can be resurfaced and renewed easily, compared to most engineered boards. Typical engineered wood products cannot be used for exposed internal applications. They require other materials to be laminated to the surface to provide durability and waterproofing. However, composite boards according to the invention comprise a unique highly decorative grain and can be used raw without any further finishing. Composite boards according to the invention may be sliced finely to use as a veneer, or thicker, to provide structural integrity for various applications. 9 EXAMPLES Test methods The test methods (corresponding to Australian and New Zealand Standards - AS/NZS) used in the Examples set out below are each incorporated by reference. Example 1 Figure 1 depicts a composite board according to the present invention which was manufactured and comprised OSB and was then tested by standard methods and compared to particle board. Property Comments Test method Density Approximately 10% AS/NZS 4266:4 more dense than typical The mass of each test piece is measured particleboard, which is and divided by the volume. generally around 600 650 density. Internal bond The internal bond is AS/NZS 4266:6 extremely high, typically A test piece is glued on the flat side particleboard is 0.3 to between 2 metal blocks and then pulled 0.6 Mpa. apart in tension so it fails across the mid section. The stress required to do this is calculated. MOE The MOE is 4-5 times AS/NZS 4266:5 that of particleboard A long piece of panel is restrained on both which would make it a ends and a load is applied to the mid-point very suitable material of the test piece, causing bending. From for load-bearing the data generated the Modulus of applications. Elasticity which is a measure of the stiffness can be calculated. MOR Similar comment to AS/NZS 4266:5 10 Property Comments Test method MOE, very strong in This is the same test as for MOE except bending. that the test piece is loaded until it breaks. From the load the Modulus of Rupture (MOR), also known as bending strength, is calculated. Formaldehyde The formaldehyde AS/NZS 4266:16 emission emission is very low, This test, also known as the desiccator equivalent to the test, requires a number of test pieces to be Japanese F rating - the placed in a sealed glass desiccator for most stringent in the 24hrs. In the base of the desiccators a world. dish containing water absorbs formaldehyde emitted into the air from the test pieces. The concentration of formaldehyde in the water is then measured. Surface The surface soundness AS/NZS 4266:7 Soundness is high. A circular metal pad is glued to surface of the test piece and a load applied until the surface layer of the test piece is pulled out. The stress required to break the surface layer is then calculated. Wet Bend A very high result. AS/NZS 4266:10 Strength Long pieces of panel suitable for bend testing are first immersed in hot water at 70*C for 2 hours. Then they are loaded in bending until they break and the MOR (bending strength) is calculated. Moisture content Similar range to AS/NZS 4266:3 11 Property Comments Test method particleboard. The test pieces (4) are placed in an oven at 105*C for 24hrs and the loss in weight from the moisture being dried out is expressed as a percentage of the dry weight. Example 2 A composite board according to the present invention was manufactured and comprised OSB and was then tested by standard methods and compared to particle board. The results are set out in the following table: Test Method Mean Std Dev Limit Units Pass Edit Thickness AS/NZS 4266:35 38.28 0.14 max. 0.3 mm Pass Edit Moisture AS/NZS 4266:3 9.7 0.7 5 - 13 o Pass Edit Density AS/NZS 4266:4 756.9 45.2 N/A kg/n 3 Edit Thickness Swell AS/NZS 4266:8 1.3 0.5 max. 12 %o Pass Edit Internal Bond AS/NZS 4266:6 2.80 6.71 min. 0.20 PPa Pass Edit MOE AS/NZS 4266:5 9147 633 PAPa Edit MOR AS/NZS 4266:5 60.8 5.37 min. 9 MPa Pass Edit Formaldehyde Emission AS/NZS 4266:16 0.24 0.00 max. 1.5 mg/L EG Pass Edit SLrface Soundness AS/NZS 4266:7 4.24 0.41 min. 0.9 MPa Pass Edit Screwholding Edge AS/NZS 4266:13 N/A N Edit Screwholding Face AS/NZS 4266:13 N/A N Edit WBS A AS/NZS 4266:10 A 33.20 4.66 min. 3.5 PAPa Pass Edit Cyclic Test (V313) - IB AS/NZS 4266:11 min. 0.15 MAPa Edit Cyclic Test (V313) - TSW AS/NZS 4266:11 max. 9 To Example 3 A composite board according to the present invention was manufactured and comprised OSB and was then tested by standard methods and compared to particle board. The results are set out in the following table: 12 Test Method Mean Std Dev Linit Units Pass Edit Thickness AS/NZS 4266:35 38.36 0.09 max. 0.3 mm Pass Edit Moisture AS/NZS 4266:3 10.4 0 6 5 - 13 % Pass Edit Density AS/NZS 4266:4 673.5 28.4 N/A kg/m3 Edit Thickness Swell AS/NZS 4266:8 1.3 0 5 max. 12 % Pass Edit Internal Bond AS/NZS 4266:6 2.36 0.29 min. 0.20 MPa Pass Erit MOE AS/NZS 4266:5 8713 452 MPa Edit NOR AS/NZS 4266: 5 57.7 5.14 minl. 9 MPa Pass Edit Formaldehyde Emission AS/NZS 4266:16 0.25 0.01 max. 1.5 mg/L EO Pass Edit SLIrface SoUndness AS/NZS 4266:7 4.04 0.41 min. 0.9 MPa Pass Edit Screwholding Edge AS/NZS 4266:13 N/A N Edit Screwholding Face AS/NZS 4266:13 N/A N Edit WBS A AS/NZS 4266:10 A 30.90 2.74 min. 3.5 MPa Pass Erit Cyclic Test (V313) - IB AS/NZS 4266:11 mIn. 0.15 MPa Edit Cydic Test (V313) - TSW AS/NZS 4266:11 max. 9 % 13