AU2006230666B2 - A laminated building material - Google Patents

Description

O-1- N AUSTRALIA c) 0 00 PATENTS ACT 1990 O COMPLETE SPECIFICATION

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on FOR A STANDARD PATENT

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o ORIGINAL Name of Applicant/s: James Hardie International Finance B.V.

Actual Inventor/s: Michael Porfida and Steven Alfred Duselis Address for Service is: SHELSTON IP Margaret Street Telephone No: (02) 9777 1111 SYDNEY NSW 2000 Facsimile No. (02) 9241 4666 CCN: 3710000352 Attorney Code: SW Invention Title: A LAMINATED BUILDING MATERIAL Details of Associated Provisional Application No. 2005905784 dated 19 Oct 2005 The following statement is a full description of this invention, including the best method of performing it known to me/us:- File: 44265AUP00 500999509 1.DOC/5844 -la-

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A LAMINATED BUILDING MATERIAL

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00 FIELD OF THE INVENTION The present invention relates to building materials and methods of IO manufacture of those materials, and in particular to building materials made from

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fibre-reinforced cement.

IO The invention has been developed primarily for use as a structural component in building construction, often used to replace timber products, and will be described hereinafter with reference to this application. However, it will be appreciated that the invention is not limited to this particular field of use.

BACKGROUND OF THE INVENTION The following discussion of the prior art is intended to provide a technical context for the invention and enable the advantages of it to be appreciated in that context. However, any reference to prior art throughout the specification should not be considered as an express or implied admission that such art is widely known or forms part of common general knowledge in the field.

Fibre-reinforced cement products are commonly applied to the external surfaces of building structures, as they have been found to be sufficiently resistant to exposure to a wide range of weather conditions, UV radiation, pollutants and carbon dioxide in the atmosphere. Fibre-reinforced cement products also have been found to be resistant to the stresses induced by significant changes in temperature and humidity in the ambient environment.

Reinforcing fibres used in such products have included cellulose (wood) fibres (see Australian Patent No. 515151), metal fibres, glass fibres and other natural fibres. Typically, the density of such building sheets is from 1.2 to 1.9 3 g/cm 3 the variation in density being achieved primarily by compression and dewatering of the fibre cement slurries used in manufacture, and by varying the -2quantity of fibres used. In contrast, the density of lumber typically ranges from 0.7

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O to 0.9 g/cm 3 for dry hardwoods and from 0.38 to 0.6 g/cm 3 for dry softwoods. O 00 The density of the fibre-reinforced cement products described above means that their characteristics of workability, nailability and handlability are less than I 5 timber and timber-based products of equal dimension. In the building industry, IDworkability refers to how well a material can be cut and/or machined, nailability Cc refers to the ease with which the material can be fastened with nails, and IDhandlability refers to the material's resistance to breakage caused by bending or folding the material. As a consequence, fibre-reinforced cement products beyond a certain thickness in building applications are constrained to a density of no more than around 0.95 g/cm 3 in order to maintain workability, nailability and handlability characteristics comparable with timber-based products.

Furthermore, conventional production techniques such as the Hatschek process impose limitations on the maximum thickness of fibre reinforced cement sheets that can be produced, which can limit their applicability in certain circumstances requiring thicker or stronger panels.

There are also specific difficulties associated with using fibre-reinforced cement products as trim components. In particular, where two adjoining exterior wall surfaces form a corner, it is usual for the fibre-reinforced cement siding sheets to be machined at adjoining ends to form complementary chamfered surfaces. The respective chamfered surfaces are then placed in complementary engagement to form a mitred corner with an aesthetically pleasing appearance. However, this method of installation places the stress concentration line of the corner along the join line of the fibre-reinforced cement sheets, thereby creating an inherent weakness at the join. As a consequence, such joins can be prone to opening up over time, thereby compromising the aesthetic appeal and potentially the weatherproofing and durability of the structure.

-3- 00 oO C OBJECT OF THE INVENTION Ct SIt is an object of the present invention to overcome or ameliorate one or more of the disadvantages of the prior art, or to at least provide a useful alternative.

IDSUMMARY OF THE INVENTION According to one aspect of the invention, there is provided a fully laminated e¢3 N building material including: two or more layers formed from pre-cured nailable low density fibre- Sreinforced cement, the layers having substantially mating surface profiles at their interface with an adjacent layer; and an adhesive layer intermediate said adjacent fibre-reinforced cement layers for bonding said fibre-reinforced cement layers together, the adhesive layer being selected and applied to substantially fill any gaps between the cement layers such that when the laminated material is cut and painted the join line between the layers is hardly visible, the adhesive being further selected and applied to provide a moisture-resistant barrier.

Advantageously, the building material is readily adaptable for use as a tile backer, wall board, wall panel, siding, trim, sheeting, decking, flooring, rail, door, screen, panel, structural member, fencing, roofing, roof decking, cladding sheet or combinations or substrates thereof.

Preferably, the adhesive enhances the resilient properties of the laminated building material.

The adhesive is preferably selected to improve the nailability of the laminated product as compared to an equivalent thickness non-laminated product of the same fibre cement material.

Preferably, the fibre cement layers have a density of no more than 0.95g/cm 3 -4- 00 oO ri In one preferred form the adhesive is a cold cure moisture curable adhesive C that is preferably a polymer adhesive and more preferably a polyurethane based adhesive.

In another form the adhesive layer includes a laminating film.

D 5 In other embodiments, the adhesive includes one or more of: a reactive hot Mc, melt glue; a radiation curable glue and a two-part glue curable by chemical reaction.

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Preferably, the intermediate bonding layer includes a reinforcing element. It is preferred that the reinforcing element is a reinforcement mesh. Preferably, the reinforcing element is embedded into the intermediate bonding layer.

It is preferred that the fibre-reinforced cement layers are made of substantially the same fibre-reinforced cement material, although it will be appreciated that layers of different fibre cement composition, density, porosity, resiliency, hardness or other physical properties may be used. Preferably, the fibrereinforced cement layers are cured.

Preferably, the fibre-reinforced cement layers are pre-formed. Preferably, the fibre-reinforced cement layers are in the form of planar sheets. The fibrereinforced cement layers may be manufactured according to any suitable method of manufacturing fibre-reinforced cement material, including the Hatschek sheet process; Mazza pipe process; Magnani process; injection moulding; extrusion; hand lay-up; moulding; casting; filter pressing; Fourdrinier forming; spattering, multiwire forming; gap blade forming; gap roll/blade forming; bel-roll forming; wellcrete and other processes.

According to a second aspect of the invention there is provided a method of making a fully laminated building material including the steps of: taking two or more layers of nailable low density cured fibre-reinforced cement, the layers having substantially mating surface profiles at their interface with an adjacent layer; 00 applying a selected adhesive layer intermediate said fibre reinforced cement layers capable of filling any gaps therebetween such that when the laminated material is cut and painted the join line between the layers is hardly visible and forming a multi layer laminate; and 5 applying pressure to the laminate to bond the reinforced fibre cement layers Ntogether and form a moisture resistant barrier therebetween.

N Preferably, the adhesive layer includes a cold cure moisture cure adhesive which is applied to at least one of any adjacent intermediate surfaces of the fibrereinforced cement layer by means of a glue roller and pressure is applied by passing the assembled laminate through nip rollers.

In a first alternative, the adhesive layer is an adhesive laminating film and the pressure is applied via a rotary laminator.

In a second alternative, the adhesive layer is a reactive hot melt glue which is heated to induce the glue to melt and bond the fibre reinforced cement boards.

Preferably, the laminated building material is formed as one or more of the following: a tile backer, wall board, wall panel, siding, trim, sheeting, decking, flooring, rail, door, screen, panel, structural member, fencing, roofing, roof decking, cladding sheet and substrates thereof. In a particular embodiment, the laminated building material is formed as a corner trim component for wall and window corners. Other preferred applications of the laminated building material include handrails, screens, baluster rails, gates, garage doors, eave overhangs, shading screens and sunshades over glazing or balcony areas.

BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: 00

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SFig. 1 is a schematic side elevation of a laminated building material according to the invention; Fig. 2 is a schematic side elevation of a comer trim component according to \tn the invention; -6-

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Fig. 3 is a schematic sectional view showing the corner trim component of Figure 2 installed in a building;

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00 Fig. 4 is a schematic view of an assembly line for manufacturing the laminated building material in accordance with the invention; and I 5 Fig. 5 is a schematic view of an alternative assembly line for manufacturing Sthe laminated building material in accordance with the invention.

INi SPREFERRED EMBODIMENT OF THE INVENTION Referring to Figure 1, the invention provides a laminated building material I in the form of a planar sheet including two layers 2 and 3 formed from fibrereinforced cement, one fibre-reinforced cement layer 3 being superimposed on top of the other fibre-reinforced cement layer 2. A bonding layer 4 intermediate the fibre-reinforced cement layers 2 and 3 includes an adhesive for bonding the fibrereinforced cement layers 2 and 3 together.

The fibre-reinforced cement used in layers 2 and 3 has a conventional formulation. One typical formulation includes an hydraulic binder, a filler material, fibre, and additives. In the preferred form the formulation and/or processing is selected to produce a cured layer of reinforced fibre cement that is nailable. In most cases these nailable products have a relatively low density and manufacturing restrictions on thickness apply as discussed above.

The hydraulic binder used in the fibre cement is preferably Portland cement but can also be any hydraulic cementitious binder chosen from a group including, but not limited to: high alumina cement, ground granulated blast furnace slag cement, gypsum hemihydrate, gypsum dihydrate, and gypsum anhydrite, or any mixtures thereof The filler, which can be a reactive or inert material, is preferably ground silica sand but can also be any material chosen from the group including, but not limited to: amorphous silica, diatomaceous earth, rice hull ash, silica fume, Smicrosilica, hollow ceramic spheres, geothermal silica, blast furnace slag, 00 granulated slag, steel slag, fly ash, mineral oxides, mineral hydroxides, clays, magnesite or dolomite, metal oxides and hydroxides, polymeric beads, or any mixtures thereof.

IND The fibre cement additives can be chosen from a group including, but not 0 limited to: silica fume, hollow ceramic spheres, cenospheres, geothermal silica, fire IND retardants, set accelerators, set retarders, thickeners, pigments, colorants, plasticisers, dispersants, foaming agents, flocculating agents, water-proofing agents, organic density modifiers, aluminum powder, kaolin, alumina trihydrate, mica, metakaolin, calcium carbonate, wollastonite, mineral oxides, mineral hydroxides, clays, magnesite or dolomite, metal oxides and hydroxides, pumice, scoria, tuff, shale, slate, perlite, vermiculite, polymeric beads, calcium silicate hydrate and polymeric resin emulsions, or any mixtures thereof. Preferred polymeric resins are products such as, but not limited to, acrylic latexes, styrene-butadiene latexes, or mixtures thereof. These latexes can be emulsions or be in a redispersible powder form. In Portland cement-based materials, the latexes need to be stabilised to withstand the high-alkali environment.

The fibres used in the fibre cement are preferably cellulose wood pulp but can also be natural or synthetic organic or inorganic fibrous material chosen from the group including, but not limited to: ceramic fibre, glass fibre, glass ceramic fibre, natural fibres such as kenaf, hemp, flax and jute, carbon fibre, mineral wool, steel fibre, synthetic polymer fibres such as polyamides, polyesters, polypropylene, polymethylpentene, polyacrylonitrile, polyacrylamide, viscose, nylon, PVC, PVA, and rayon, or any mixtures thereof. The fibres are more preferably fibrillated cellulose fibres, such as described in Australian Patent No. 515151.

The fibre-reinforced cement layers 2 and 3 may be formed into any desired shape or article prior to forming the laminated fibre-reinforced cement sheet 1. The fibre-reinforced cement layers 2 and 3 are from a plastic mixture or an aqueous -0-

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slurry, with or without post pressing, by any one or more of a number of O conventional processes such as the Hatschek sheet process; Mazza pipe process; 00 Magnani process; injection molding; extrusion; hand lay-up; moulding; casting; filter pressing; Fourdrinier forming; spattering; multi-wire forming; gap blade forming; gap roll/blade forming; bel-roll forming; wellcrete and other processes.

IND These processes may also include post-forming processes such as pressing, embossing, trimmimg and others, after the articles to become the fibre-reinforced Icement layers 2 and 3 are formed, but before they are cured. The processing steps and parameters used to achieve the final product using a Hatschek process are similar to those described in Australian Patent No. 515151. Thus, after the processing described above, the formed article is in a plastic state, enabling it to retain its shape and be capable of moulding. The step of curing the fibre-reinforced cement articles is subsequently performed, prior to forming the laminated fibrereinforced cement sheet 1.

In the illustrated preferred embodiment, the fibre cement layers are in sheet form and produced by the Hatschek process. The adhesive forming the intermediate bonding layer 4 is a moisture curing, cold curing glue. The adhesive is preferably moisture-durable and is selected and applied so as to be able fill any gaps between the two fibre-reinforced cement layers 2 and 3 so that when the laminated fibre-reinforced cement sheet 1 is cut and painted, the join line 5 is hardly visible.

Alternative adhesives includes reactive hot melt glues, polymer glues, laminating films, non-cementitious binders and other suitable adhesives.

Samples of the laminated sheet 1 were made having a thickness of 38 mm using nailable, relatively low density fibre-reinforced cement sheets produced by the Hatschek process having a thickness of 19mm and bonded together by a moisture curable polyurethane adhesive. A preferred form of the moisture curable polyurethane adhesive is sold by the company Bostik Findley under the product name "Ultraset SF". In the referenced embodiment, the adhesive is applied at a rate of about 385g per square metre on each face. This results in an adhesive thickness

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Sof approximately 3mm, which is a quantity sufficient to accommodate the material

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O roughness and fill the gaps to provide a continuous moisture resistant bond layer.

oO 00 _It has been unexpectedly discovered that the intermediate bonding layer 4 in these sample sheets formed a moisture-resistant barrier independently of any I 5 additives in the fibre-reinforced cement layers 2 and 3.

Cc In addition, samples of the laminated sheet 1 were found, surprisingly, to IDdemonstrate improved workability and handlability characteristics, in comparison to conventional fibre-reinforced cement sheets of equivalent thickness. In this regard, and without limiting the efficacy of the invention to any particular theoretical 0to postulation, it is believed that the cured glue enhances resistance of the laminated sheet 1 to deformation caused by bending or folding, and thus improves the handlability characteristics of the laminated sheet 1. Samples of the laminated sheet 1 were also discovered, surprisingly, to have improved nailability characteristics over equivalent conventional fibre-reinforced cement sheets of the same thickness (38 mm). Thus, the laminated sheet 1 can be produced in greater thicknesses, whilst providing improved properties of handlability, nailability and workability, with respect to known fibre-reinforced cement products of comparable thickness.

Consequently, the laminated sheet 1 is more versatile in its use in a variety of building applications than existing fibre-reinforced cement products. For example, the laminated building material is suitable for being formed as one or more of the following: a tile backer, wall board, wall panel, siding, trim, sheeting, decking, flooring, rail, door, screen, panel, structural member, fencing, roofing, roof decking, cladding sheet and substrates thereof. Other suitable applications of the laminated building material in particular include handrails, screens, baluster rails (balusters and baluster cross-members) screening rails, sliding panels, gates, garage doors, eave overhangs, shading screens and sunshades over glazing or balcony areas.

Figures 2 and 3 show one particular building application of the laminated fibre-reinforced cement sheet 1, where corresponding features have been given the same reference numerals. The laminated fibre-reinforced cement sheet 1 has been

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machined to form a corner trim component 6. As best shown in Figure 2 by dotted O lines, the section X of the laminated sheet 1 has been machined away below the oo intermediate bonding layer 4 to form a comer panel. The glue or join line 5 of the trim component 6 is defined by the bonding layer 4. Consequently, the trim component 6 has greater resistance to stress, since the join line 5 is has been displaced from the stress concentration line 7. Although a 900 corner is illustrated, Sit will be appreciated that other desired angles and shapes may be readily formed, by appropriate machining processes.

C, Referring to Figure 3, the comer trim component 6 is shown installed in a building structure. Two walls 8 are fixed to a post 9 of a frame by suitable fasteners in the form of nails 10. The corner trim component 6 is then fitted to the walls 8 and is secured by a nail 11 longer than the nails 10, extending through the fibrereinforced cement layer 2 of the corner trim component 6, to penetrate one wall 8 and the post 9.

Samples of the corner trim component 6 were unexpectedly found to have improved nailability characteristics and the nail 11 easily penetrated the fibrereinforced cement layer 2, wall 8 and post 9 for quick installation. In contrast, an equivalent fibre-reinforced cement sheet of the same thickness was significantly more difficult to install.

In addition, the comer trim component 6 unexpectedly provided advantages over the prior art in its strength and aesthetic appeal. As discussed previously, it was necessary in the prior art to machine the ends of the fibre-reinforced cement sheets to form complementary chamfered surfaces to create a mitred corner. This resulted in the join line coinciding with the stress concentration line 7, thereby inherently weakening the join. In contrast, the trim component 6 has its join line displaced from the stress concentration line 7. Furthermore, the join line 5 is not visible after it has been painted.

Referring to Figure 4, an assembly line 12 for manufacturing the laminated building sheet 1 is shown. The assembly line 12 includes an infeed roller conveyor -11-

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S13, a glue spreader 14, an intermediate roller conveyer 15, a pair of nip rollers 16 O and an outfeed roller conveyer 17.

00 0The infeed roller conveyer 13 feeds a first raw pre-formed fibre-reinforced cement board into the glue spreader 14, which then applies the moisture cold curing IND 5 glue to the first fibre-reinforced cement board. In the preferred form a heavily IND grooved roller is used which enables application of the desired thickness of adhesive up to around 3mm for the sheets used in the sample. Preferably, the Iglue spreader is set to run as fast as possible to help the glue stay on the roller using Scentrifugal force. Typical speed in the sample set up is about 36m/min. The first fibre-reinforced cement board then proceeds to the intermediate roller conveyor where a second pre-formed fibre-reinforced cement board is superimposed on top of the glued surface of the first fibre-reinforced cement board. The first and second fibre-reinforced cement boards are adjacent each other so that the glue forms a bonding layer intermediate the first and second fibre-reinforced cement boards. The first and second fibre-reinforced cement boards are then drawn between the nip rollers 16, which apply pressure to the outer surfaces of the fibre-reinforced cement boards to promote bonding of the fibre-reinforced cement boards at the glued surfaces.

In the preferred form, the nip pressure is around 180 pounds per lineal inch (around 3.24 kg per lineal millimetre) and the nip roller speed is slower than the glue spreader to maximise time under pressure. Typical speed is about 12m/min.

After exiting the nip rollers 16, the now laminated fibre-reinforced cement sheet proceeds along the outfeed roller conveyor 17 for stacking or further processing.

Overnight curing of the laminate in a stack formation has been found beneficial to producing a uniform glue line.

Referring to Figure. 5, an automated assembly line is shown, where corresponding features have been given the same reference numerals. The automated process assembly line 18 has the same elements as the assembly line 12 shown in Figure 4. However, the infeed conveyer 13, intermediate roller conveyer -12- 15 and the outfeed roller conveyer 17 are motorised and their respective speeds C) synchronised with each other and with the glue spreader 14 and the nip rollers 16.

00 0The automated assembly line 18 also incorporates two sets of vacuum lifters 19 respectively associated with the infeed roller conveyor 13 and the intermediate ID s roller conveyor 15. The vacuum lifters 19 can be manually operated or form part of IDan automated system, controlled by a computer. A scissor lift 20 is additionally provided adjacent the outfeed roller conveyer 17 for stacking the laminated sheets

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Manufacture of the laminated sheet 1 using this apparatus is performed in a manner similar to that described above in relation to Figure 4. In the automated assembly line 18, the associated vacuum lifters 19 respectively loads the first fibrereinforced cement board onto the infeed roller conveyor 13 and locates the second fibre-reinforced cement board into position on the first fibre-reinforced cement board. In addition, the scissor lift 20 receives the laminated fibre-reinforced cement sheet 1 from the outfeed roller conveyor 17, and indexes down so as to allow the laminated fibre-reinforced cement sheets to be stacked for easy transport by a fork lift or pallet jack.

Where the adhesive is a laminating film, the nip rollers 16 are replaced by a rotary laminator. Similarly, where the adhesive is a reactive hot melt glue, the nip rollers 15 are replaced by a suitable heating or autoclaving machine to induce the glue to melt and bond the fibre-reinforced cement boards.

Additional embodiments employ fibre-reinforced cement sheets that are cured and sealed pre- or post-autoclave in order to strengthen the boards and promote water resistant properties.

In other embodiments, the intermediate bonding layer includes a reinforcement mesh to improve its strength and resistance. This is useful where the sheet is used for fencing, privacy screens, corridor walls and rails or balustrades in decking handrails, flooring or decking. Other embodiments of the laminated -13-

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building material adopt shapes other than a planar sheet, such as cylindrical, circular, pyramidal, prismatic and other irregular shapes.

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_Other embodiments include the additional step of applying the adhesive to the second fibre-reinforced cement board prior to locating the second fibrereinforced cement board adjacent the first fibre-reinforced cement board. In one Ipreferred embodiment, a reinforcement mesh is embedded in the intermediate bonding layer after applying the adhesive to the first fibre-reinforced cement board.

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C In the preferred form, the cured fibre cement layers are laminated by coating one layer on the back and the adjacent layer on the front face. This allows the finished product to look no different to a standard non-laminated sheet. This has two benefits. Firstly, the uncured fibre-reinforced cement sheets conform to one another when they are made and stacked, so assembling them in the same orientation gives a better mating of the surfaces. Secondly, if the finished product is then sealed on five sides excluding the back rough surface, correct installation is easier as the unsealed surface is easier to distinguish.

It is also envisaged in a further embodiment that the two felt surfaces of the fibre-reinforced cement boards are glued together to produce a roller smooth surface on the outer surfaces of the assembled sheet, resulting in a more uniform laminated product. However, where it is preferred to minimise the amount of adhesive used in the manufacturing process, the respective surfaces of the fibrereinforced cement boards to be glued may be pre-sanded to remove any variations in thickness. Alternatively, the laminated product may be sanded after gluing if the thickness variation is too great. Although the invention has been described primarily in terms of two laminates, it will be appreciated that three or more laminates, with respective intermediate bonding layers, may also be used to provide the desired thickness, strength, durability, insulation and other properties.

It will be appreciated that the invention, at least in its preferred embodiments, provide a laminated building materials having unexpected advantages in terms of improved strength, moisture-resistance, workability, -14- Cr nailabillity and handlability characteristics, compared with fibre-reinforced cement products of equivalent dimensions. This permits versatile application of the 00 laminated building material in thicknesses beyond existing fibre-reinforced cement products. In these and other respects, the invention represents a practical and commercially significant improvement over the prior art.

0Furthermore, the preferred use of cold curing moisture curing polyurethane adhesive has a number of advantages over most of the alternatives and is I particularly suited to this application. For example these adhesives are a one Scomponent system so there is no need to meter or mix additives. The moisture in the fibre cement sheets is enough to drive the cure action and once cured, any additional moisture contact does not degrade the adhesive bond. In terms of ease of manufacture, these adhesives do not release any volatile organic compounds during cure or any noxious odours. They tolerate wide temperature and moisture variations and have a long working time which means operator can run a full eight hour shift without the need to clean the glue roller due to adhesive going off.

Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.

Claims (19)

1. A fully laminated building material including: two or more layers formed from pre-cured nailable low density fibre- reinforced cement, the layers having substantially mating surface profiles at their IND 5 interface with an adjacent layer; and INO an adhesive layer intermediate said adjacent fibre-reinforced cement layers 0 Cc for bonding said fibre-reinforced cement layers together, the adhesive layer being INO selected and applied to substantially fill any gaps between the cement layers such that when the laminated material is cut and painted the join line between the layers is hardly visible, the adhesive being further selected and applied to provide a moisture-resistant barrier.

2. A fully laminated building material according to claim 1 wherein the adhesive is selected to enhance the resilient properties of the laminated building material.

3. A fully laminated building material according to claim 1 or claim 2 wherein two layers are laminated to achieve a planar material having a thickness of about 38 mm.

4. A fully laminated building material according to any one of the preceding claims wherein the adhesive layer acts to improve the nailability of the laminated material as compared to a non-laminated product of the same fibre cement and equivalent thickness. A fully laminated building material according to any one of the preceding claims wherein the adhesive layer includes a cold curable moisture curable adhesive.

6. A fully laminated building material according to claim 5 wherein the adhesive is a cold curable moisture curable polymer adhesive.

7. A fully laminated building material according to claim 5 wherein the adhesive is a cold curable moisture curable polyurethane based adhesive.

8. A fully laminated building material according to any one of claims 1 to 4 wherein the adhesive layer is in the form of an adhesive laminating film. -16- 00

9. A fully laminated building material according to any one of claims 1 to 4 a wherein the adhesive layer is in the form of a reactive hot melt glue. A fully laminated building material according to any one of the preceding Sclaims wherein the density of the fibre cement is no more than approximately 0.95 3 g/cm. I11. A fully laminated building material according to any one of the preceding Sclaims wherein the primary reinforcing fibre is cellulose wood pulp fibre.

12. A fully laminated building material according to any one of the preceding Sclaims wherein the additives in the fibre cement sheets is chosen from the group including: silica fume, hollow ceramic spheres, cenospheres, geothermal silica, fire retardants, set accelerators, set retarders, thickeners, pigments, colorants, plasticisers, dispersants, foaming agents, flocculating agents, water-proofing agents, organic density modifiers, aluminum powder, kaolin, alumina trihydrate, mica, metakaolin, calcium carbonate, wollastonite, mineral oxides, mineral hydroxides, clays, magnesite or dolomite, metal oxides and hydroxides, pumice, scoria, tuff, shale, slate, perlite, vermiculite, polymeric beads, calcium silicate hydrate and polymeric resin emulsions, or any mixtures thereof.

13. A fully laminated building material according to any one of the preceding claims wherein the adhesive layer includes a reinforcing element.

14. A fully laminated building material according to claim 13 wherein the reinforcing element is a reinforcing mesh. A trim component manufactured from a fully laminated building material according to any one of the preceding claims.

16. A corner trim component machined from a fully laminated building material in accordance with any one of claims 1 to 14 wherein the internal corner is formed at a location spaced from the lamination line.

17. A method of making a fully laminated building material including the steps of: 17- 00 O taking two or more layers of nailable low density cured fibre-reinforced acement, the layers having substantially mating surface profiles at their interface with an adjacent layer; applying a selected adhesive layer intermediate said fibre reinforced cement layers capable of filling any gaps therebetween such that when the laminated material is cut and painted the join line between the layers is hardly visible and forming a multi layer laminate; and applying pressure to the laminate to bond the reinforced fibre cement layers together and form a moisture resistant barrier therebetween.

18. A method according to claim 17 wherein the adhesive layer includes a cold cure moisture cure adhesive which is applied to at least one of any adjacent intermediate surfaces of the fibre-reinforced cement layer by means of a glue roller and pressure is applied by passing the assembled laminate through nip rollers.

19. A method according to claim 17 wherein the adhesive layer is an adhesive laminating film and the pressure is applied via a rotary laminator. A method according to claim 17 where the adhesive layer is a reactive hot melt glue which is heated to induce the glue to melt and bond the fibre reinforced cement boards.

21. A fully laminated building material substantially as herein described with reference to any one of the embodiments of the invention illustrated in the accompanying drawings and/or examples.

22. A trim component substantially as herein described with reference to any one of the embodiments of the invention illustrated in the accompanying drawings and/or examples.

23. A method of making a fully laminated building material substantially as herein described with reference to any one of the embodiments of the invention illustrated in the accompanying drawings and/or examples.

24. A method of making a trim component substantially as herein described with reference to any one of the embodiments of the invention illustrated in the accompanying drawings and/or examples.