WO2024130336A1

WO2024130336A1 - A non-woven biopolymer board

Info

Publication number: WO2024130336A1
Application number: PCT/AU2023/051362
Authority: WO
Inventors: Tony Sutton
Original assignee: Woven Image Pty Limited
Priority date: 2022-12-22
Filing date: 2023-12-22
Publication date: 2024-06-27

Abstract

The present invention is, in a first aspect, a substantially rigid and homogenous board substantially formed of a mix of fibres in a non-woven state, wherein the fibre mix comprises from about 50% to about 70% by weight animal wool fibres, and from about 30% to about 50% by weight polylactic acid (PLA) fibres, the animal wool fibres have a thickness substantially between 15-45 um, the PLA fibres have a denier measurement substantially between 1-8 denier, at least a portion of the PLA fibres are substantially achromatic, at least one portion of the non-woven fibres are coloured, and the fibres of the fibre mix are dispersed such that the board exhibits a marie-effect colour. Also provided is a method of producing the same.

Description

A NON-WOVEN BI OPOLYMER BOARD

PRI ORI TY CLAI M

[0001 ] The present application claims priority from AU 2022903960, filed in Australia on 22 December 2022. The contents of the priority application are hereby incorporated herein by reference.

TECHNI CAL Fl ELD

[0002] The present invention relates generally to the field of boards, panels, tiles and acoustic elements for use in commercial or residential spaces.

BACKGROUN D

[0003] Room dividers, wall panels, partitioning, workstation panels, ceiling tiles, and acoustic ceiling blades are increasingly being fabricated from non-woven recycled Polyethylene terephthalate (PET), for example the EchoPanel® product lines, or by sim ilar means using virgin PET. Aside from their functional use, such boards are aesthetically pleasing and increase the amenity of the room including by reducing sound reverberation. Such boards are also finding use in improving suitability of various spaces for neurodivergent people, particularly people at risk of sensory overstimulation by assisting in m itigating, softening and otherwise ameliorating the sensory impact of sounds, colours and/or textures within the space.

[0004] However, the use of PET boards is not without significant problems. I ncreasingly there is a desire for such products to be made from sustainable and low energy intensity materials, to exhibit a reduced carbon em ission footprint, and to satisfy incrementally more onerous fire safety standards.

[0005] Recycled PET and other synthetic-based products sourced through recycling are not particularly sustainable, despite the use of recycled synthetics being less energy intensive in manufacture than the use of virgin synthetics. I ndeed, the process is relatively energy intensive regardless of the recycling methodology adopted, and PET cannot be infinitely recycled through mechanical processes due to degradation of the plastic’s molecular properties - in effect, PET of older ‘generations’ (/.e. have been through more recycling cycles) are notably weaker and more brittle than newer or younger PET plastics. Chem ical means of recycling PET plastics, which lim it the degradation process and thus extend the plastic’s usable life, are in development, but these developments are still early and not yet cost-effective at commercial scale. Additionally, access to com mercial textile recycling ( whether mechanical or chemical) is lim ited - and the raw material is ultimately derived from fossil fuels and therefore is non-renewable.

[0006] Furthermore, the use of PET and other synthetics in the fitment of buildings is increasingly being restricted by evolving fire safety standards and testing regimes. I ndeed, in the present day many synthetic products are incapable of meeting certain countries’ building codes for fire safety, because PET and other thermoplastic materials are too combustible, or are combustible at too low a temperature, to pass the more stringent testing applied. The aforementioned increasing generational age of recycled PET also appears to be correlated to a reduced fire safety, with products manufactured from PET of older generations perform ing worse than ‘virgin’ (never recycled) PET or even younger PET. The alternative to synthetic PET plastics is the use of biopolymers. PLA polymers are one type of biopolymer that may provide a potential source. PLA polymer is particularly desirable as it is able to be derived from renewable resources such as sugar beet, sugarcane and other plant-based sources.

[0007] However, the mechanical properties of PLA polymers fall between polystyrene and PET (albeit without suffering generation-linked mechanical degradation) , the glass transition temperature is between 60-65 °C, and PLA polymers have a melting temperature in the range of 130-180 °C. Additionally, while PLA fibres are less flam mable than PET fibres, they are still more flam mable than is desirable. Overall, while PLA fibres provide the desirable benefit of sustainability, they are not ideal for use as the sole or primary material in constructing boards intended for use as fitments in commercial spaces.

[0008] Animal wool has been recognised as another target fibre source for nonwoven boards. Wool is a rapidly renewable resource that contains naturally sequestered atmospheric carbon; about 50% by weight of clean wool fibre is pure biogenic carbon. Converted into carbon equivalents (CO2-e) , 1 kg of clean wool equates to about 1 .8kg of CO2-e when stored in a durable usable form .

[0009] Wool is also self-extinguishing, and is considered to be inherently fire resistant, thereby making it ideal for constructing panels that m ust adhere to rigorous fire safety standards. Wool is naturally high in nitrogen (~ 15- 16% w/w) , high in sulphur (~ 3-4% w/w) , low in hydrogen (~ 6 7% w/w) , and high in moisture regain (~ 8-16% w/w) which means that it does not support combustion until 570- 600°C, which can be contrasted with PET which will support combustion from 485- 560°C. A wool-rich product with lower thermoplastic content will be better positioned to achieve higher performance ratings in fire classifications particularly in ceiling applications where the fire codes are most stringent.

[0010] Wool is also considered to potentially improve ambient air quality. Research has shown that com mon volatile organic compounds (VOCs) and other air pollutants and odours can be absorbed, neutralised and chem ically bonded by various varieties of sheep’s wool at varying levels, improving the quality of indoor environments.

[001 1 ] The skilled person will appreciate that animal wool comprises m icroscopic scales on an outer surface of each fibre, which provide - under the right conditions - the ability for the fibres to bind together, enabling production of yarn and other soft materials from the wool. However, the natural binding ability of wool does not provide sufficient rigidity to enable production of a board suitable for use in room dividers, wall panels, partitioning, workstation panels, ceiling tiles, acoustic ceiling blades and other com mercial or residential fitments. Therefore, use of animal wools as a primary material would also require the use of adhesives, reagents or other bonding agents in order to be manufactured into a fibre board fit for purpose. Use of adhesives is undesirable, as sustainable adhesives that are fit for purpose are difficult to source, while other adhesives can be toxic, expensive, difficult to work with or otherwise pose issues such as degradation.

[0012] It is therefore considered that a combination of PLA polymer fibres and animal wool fibres may provide a means of producing a sustainable board that is both fire-safe and does not require any further adhesives. [0013] A significant problem with non-woven boards is that plain colours are hard to seam lessly mate together without the join that is disposed between two boards being visible. Such visible joins are quite com mercially undesirable.

[0014] One prior art solution to this problem that has been realised by the present inventors, is to provide a marie-effect colourway that camouflages the joins but whereby the m ultiple colours read as a single colour to the human eye. I n particular the standard PET-based EchoPanel® is a combination of substantially-achromatic black and white fibres (approximately 20% black fibre and 80% white fibre by weight) that provides a seam less join and that reads as a m id-grey.

[0015] However, when attempting to blend fibres to create such chromatic colourways, the introduction of a dark yarn into a chromatic colour (i.e. other than white) to create a marled effect m ust be performed with a very small portion of the dark fibre, otherwise the colourway assumes an off shade of grey. Furthermore, the use of more than 3-5% of dark fibre tends to create a clumpy and uneven appearance. However, such a small percentage means that the dark fibres nevertheless do not blend well enough before the web is formed.

[0016] The present invention arose out of a desire to overcome or at least ameliorate some of the deficiencies of the prior art, in particular in relation to woollen-based products.

DI SCLOSURE OF THE I NVENTI ON

[0017] I n a first aspect, the present invention comprises a substantially rigid and homogenous board substantially formed of a m ix of fibres in a non-woven state, wherein the fibre m ix comprises from about 50% to about 70% by weight animal wool fibres, and from about 30% to about 50% by weight polylactic acid (PLA) fibres, the animal wool fibres have a thickness substantially between 15-45 pm , the PLA fibres have a denier measurement substantially between 1 -8 D, at least a portion of the PLA fibres are substantially achromatic, at least one portion of the non-woven fibres are coloured, and the fibres of the fibre m ix are dispersed such that the board exhibits a marie-effect colour, the marie-effect colour being a combination of colours of at least the substantially achromatic PLA fibre portion and the or each coloured non-woven fibre portion.

[0018] I n an embodiment, the substantially achromatic PLA fibre portion are substantially black or substantially white. I n an embodiment, the substantially achromatic PLA fibre portion comprise less than about 10% by total weight of the fibre m ix. I n an embodiment, the substantially achromatic PLA fibre portion comprise from about 3% to about 5% by total weight of the fibre m ix. I n an embodiment, the substantially achromatic PLA fibre portion comprises PLA fibres having a thickness of about 2 D.

[0019] I n an embodiment, the or each coloured fibre portion are a further portion of the PLA fibres, a portion of the animal wool fibres, or a combination thereof. I n an embodiment, there are at least two coloured fibre portions that are different colours. I n an embodiment, the coloured fibre portion is coloured either naturally, artificially, or a combination thereof.

[0020] I n an embodiment, the thickness of the animal wool fibres is substantially between 20-35 pm . I n an embodiment, the thickness of the animal wool fibres is substantially between 27-32 pm .

[0021 ] I n an embodiment, at least a portion of the PLA fibres are low melt PLA fibres. I n a further embodiment, the low melt PLA fibres are bicomponent low melt PLA fibres.

[0022] I n an embodiment, the fibres of the fibre m ix have a staple length of 30- 80 m m .

[0023] I n an embodiment, a portion of the fibres of the fibre m ix are not coloured, such that the marie-effect colour is a combination of colours of at least the substantially achromatic PLA fibre portion, the or each coloured fibre portion, and the non-coloured fibre portion.

[0024] I n an embodiment, the fibre board has a thickness between 5- 15 m m . [0025] A second aspect of the invention lies in a method of producing a fibre board, comprising, in any suitable order, the operations of:

• Opening and blending animal wool fibres and polylactic acid (PLA) fibres into a fibre m ix having a marie-effect colour;

• carding the fibre m ix into a fibre web;

• cross-lapping the fibre web;

• at least one of needle-punching and air-texturing the fibre web; and

• compressing the fibre web between heated rollers.

[0026] I n an embodiment, the operation of opening and blending the animal wool fibres and PLA fibres is repeated at least once.

[0027] I n an embodiment, the heated rollers compress the fibre web with a pressure of at least 600 kPa. I n an embodiment, the heated rollers have a roller clearance that is 1 m m or less. I n an embodiment, the fibre web is compressed between the heated rollers at a feed rate between 0.5-3 m/m in. I n an embodiment, the heated rollers are heated to a temperature between 150- 180°C. I n an embodiment, the heated rollers are heated to a temperature between 160- 170°C.

[0028] I n an embodiment, the fibre web is needle-punched, the operation of needle-punching is conducted at least twice, a first needle-punching being conducted on one side of the fibre web, and a second needle-punching being conducted on a second, opposing side of the fibre web.

[0029] I n an embodiment, the method further comprises the operation of heating the fibre web prior to compressing the fibre web between heated rollers. I n an embodiment, the fibre web is heated within an oven having a temperature between 140- 170°C. I n an embodiment, the oven temperature is between 150- 160°C. I n an embodiment, the fibre web is heated for 80- 1 10 seconds.

[0030] I n an embodiment, the method further comprises, after the operation of compressing the fibre web between heated rollers, the operation of compressing the fibre web between cooling rollers. I n an embodiment, the cooling rollers compress the fibre web with a pressure of at least 600 kPa. I n an embodiment, the cooling rollers have a roller clearance that is 1 m m or less. I n an embodiment, the fibre web is compressed between the cooling rollers at a feed rate between 0.5-3 m/m in.

[0031 ] I n an embodiment, the method further comprises at least one of:

• thermoform ing the fibre board into a desired shape; or

• embossing, impressing or otherwise form ing a surface feature into a surface of the fibre board; or

• both thermoforming and embossing, impressing or otherwise form ing the surface feature into the surface of the fibre board.

[0032] I n an embodiment, the shaping operation is conducted at an operating pressure substantially between 5-8 MPa. I n an embodiment, a temperature adjustment operation is conducted prior to the shaping operation.

[0033] Further or alternative embodiments of the invention may be disclosed herein, or may otherwise become apparent to the person skilled in the art through the disclosure herein. These and other embodiments are considered to fall within the scope and object of the invention.

DEFI NI TI ONS

[0034] As used herein, the term “marie effect” refers to a visual effect wherein an aggregate textile exhibits a particular colour (the “marie-effect colour”) that is achieved by physical dispersion of the aggregate textile’s individual component fibres, each having separate colours, throughout the aggregate textile. While each component fibre retains its own colour, the aggregate textile when viewed as a whole has the appearance of a particular colour which is a combination of the colours of the individual component fibres. The skilled person will appreciate that the marie effect is a visual effect that is readily exhibited on the macro scale, i.e. when the aggregate is viewed at a distance such that individual components of the aggregate are not easily discernible. On the micro scale, i.e., if exam ined closely enough that individual components can be readily and easily discerned from one another, it would become more apparent that the individual components of the aggregate textile are different colours. DESCRI PTI ON OF Fl GURES

[0035] Embodiments of the present invention will now be described in relation to figures, wherein:

Figure 1 depicts an embodiment of a fibre board of the present invention;

Figures 2 & 3 depict embodiments of the fibre board having been shaped;

Figure 4 depicts an embodiment of a method of producing a fibre board of the present invention; and

Figures 5-8 depict various further, non-exclusive embodiments of the method comprising additional operations and/or sub-operations.

[0036] While not every feature may be depicted in every figure listed above, the mere lack of depiction of two or more particular technical features in the same figure is not to be interpreted as indicating that said particular technical features are m utually exclusive to one another or that an embodiment comprising some or all of these technical features falls outside of the scope of the invention. The person skilled in the art will appreciate that elements may be, for example, excluded from figures to ensure that the elements that are depicted therein are not occluded, obscured or otherwise rendered unclear.

DETAI LED DESCRI PTI ON OF PREFERRED EMBODI MENTS

[0037] I n a first aspect the present invention may lie in a substantially rigid board that is substantially formed of at least two different types of fibres (Referred to hereafter as the ‘fibre mix’) , wherein the fibres are not woven together to form the board. There is an effectively uniform compositional ratio of the at least two different types of fibres within and across the board. I n an embodiment, the fibre m ix may comprise from about 50% to about 70% by weight animal wool fibres, and from about 30% to about 50% by weight polylactic acid (PLA) fibres. I n an embodiment, the animal wool fibres may be carbonised animal wool fibres.

[0038] Without lim iting the scope of the invention through theory, it is considered that a combination of PLA fibres and animal wool fibres may provide a synergistic effect wherein each fibre counteracts the drawbacks of the other. By utilising a fibre m ix that is predom inantly animal wool fibre, the flam mability of the resulting board can be severely improved from a safety standpoint. The PLA fibres, having both a low glass transition temperature and melting point, can be used to bind the fibres within the fibre m ix together by applying heat and compression, then allowing the fibre m ix to cool, thereby avoiding the need for adhesives, reagents or other binding means.

[0039] Prelim inary research also suggests that a panel manufactured with wool fibre blended with PLA fibre may result in a product with a lower carbon footprint than a 100% synthetic alternative. For example, the upfront carbon footprint of 1 kg of 12mm EchoPanel® is 3.5kg CO2-e. I n contrast, and drawing upon product stage Global Warm ing Potential (GWP) data from the assessment of 100% New Zealand grown wool formed into non-woven insulation batt such as Havelock Wool I nsulation, and the product stage GWP of Poly Lactic Acid (PLA) polymer, the upfront carbon footprint of 1 kg of Havelock Wool I nsulation is 2.6kg CO2-e, while the upfront carbon footprint of PLA polymer as reported by TotalEnergies Corbion is 0.5kg CO2-e. It is therefore anticipated that significant reductions in carbon footprint may be able to be achieved by manufacturing products that are ordinarily manufactured from PET from wool and/or PLA fibre instead.

[0040] I n an embodiment, the board is of sufficient rigidity to be utilised in the construction or formation of elements such as room dividers, wall panelling, partitions, privacy or modesty screens, workstation panels, ceiling tiles, and acoustic panelling or acoustic blades. The person skilled in the art will appreciate that this is a qualitative property.

[0041 ] I n an embodiment, the board has a thickness that is substantially between 5 m m to 15 mm . I n a further embodiment, the board may have a thickness that is substantially between about 5 m m to about 10 mm . I n a further embodiment, the board may have a thickness that is substantially between about 6 m m to about 9 m m . I n an alternate further embodiment, the board may have a thickness that is substantially between about 10 mm to about 15 mm . I n a further embodiment, the board may have a thickness that is substantially between about 10 m m to about 12 mm .

[0042] I n an embodiment, the PLA fibres may provide binding or bonding between the fibres of the fibre m ix. I n a further embodiment, at least a portion of the PLA fibres may be at least partially melted and allowed to re- solidify during at least one operation of the board’s formation in order to promote bonding between fibres of the fibre m ix. I n a further embodiment, at least a portion of the PLA fibres may be low-melt PLA fibres for ease of partial melting. I n a further embodiment, the low- melt PLA fibres may be bicomponent low- melt PLA fibres. I n one example embodiment thereof, the bicomponent low-melt PLA fibres comprise an outer sheath formed of low-melt PLA, while the inner ‘core’ is any suitable PLA.

[0043] I n an embodiment, at least a portion of the PLA fibres are substantially achromatic. The skilled person will appreciate that while the substantially achromatic PLA fibre portion is achromatic (i.e. being having no or a substantially reduced hue) , this portion is not necessarily clear or translucent. The substantially achromatic PLA fibre portion may have any particular shade ranging from black through grey to white, and so may provide a means of controlling or adjusting the ‘lightness’ of the fibre m ix and the resulting board without meaningfully altering its hue. I n a further embodiment, the substantially achromatic PLA fibre portion may be substantially black or substantially white.

[0044] I n an embodiment, the substantially achromatic PLA fibre portion may comprise less than about 10% by total weight of the fibre m ix. I n a further embodiment, the substantially achromatic PLA fibre portion may comprise from about 3% to about 5% by total weight of the fibre m ix.

[0045] At least one portion of the fibre m ix may be coloured. The coloured fibre portion or portions may be a further portion of the PLA fibres, a portion of the animal wool fibres, or a combination thereof. The coloured fibre portion may be coloured using any conventional means known in the art that is compatible with animal wool fibre and/or PLA fibre and with a formation process that utilises heating. I n an embodiment, the coloured fibre portion is coloured either naturally, artificially, or a combination thereof. I n one embodiment, the coloured fibre portion comprises at least a portion of the animal wool fibres. I n a further embodiment, there may be at least two coloured fibre portions that are different colours. I n a further embodiment, at least a portion of the fibre m ix may not be coloured. [0046] I n an embodiment, the substantially achromatic PLA fibre portion, the or each coloured fibre portion, and the non-coloured fibre portion (if any) are blended together so as to be each dispersed throughout the board.

[0047] Without lim iting the scope or object of the invention through theory and with reference to Figure 1 , it is envisaged that blending together each fibre portion may enable a “marie effect” to be achieved across the fibre m ix, such that the formed board 100 may have or exhibit a “marie-effect colour” when viewed on a ‘macro’ scale. I nset 1 A depicts a m icro-scale/close-up view of an example embodiment of the board 100, wherein the substantially achromatic PLA fibre portion 102 forms the darkest regions, the coloured fibre portions 104 form m idtone regions, while the non-coloured fibre portion 106 form the lightest region. The marie-effect colour of the board 100 may be a combination of the colours of at least the substantially achromatic PLA fibre portion 102, the or each coloured fibre portion 104, and the non-coloured fibre portion 106 (if present) . It is envisaged that coloured fibre portions affect the ‘hue’ of the marie-effect colour, while the substantially achromatic PLA fibre portion provides for control of the ‘lightness’ of the marie-effect colour without meaningfully effecting the ‘hue’. The non-coloured fibre portion 106 (if present) may affect either or both the ‘hue’ and the ‘lightness’ of the marie-effect colour, depending on its characteristics. The person skilled in the art will appreciate that this differentiation is most easily discernible at the ‘m icro’ scale (i.e. upon close examination). The person skilled in the art will further appreciate that Figure 1 and I nset 1 A are examples only and are not intended in any way to lim it the scope or object of the invention.

[0048] It is envisaged that providing the board with marie-effect colouration may enable m ultiple boards to be mated together while occluding, obscuring or otherwise camouflaging the seam between two adjacent boards. With reference to I nset 1 A, it is envisaged that said camouflaging may be provided by the mottling that gives rise to the marie effect in the fibre board, in a manner sim ilar to how traditional camouflage ‘breaks up’ the silhouette of the camouflaged entity when viewed against or alongside sim ilar colours.

[0049] I n an embodiment, the animal wool fibres may have a thickness substantially between 15-45 pm , while the PLA fibres have a Denier measurement substantially between 1 -8 D. It has been found that the use of finer fibres enables the various fibre portions to be blended together more evenly, and the resulting boards were typically more rigid and thus suitable for their intended purpose. However, as the skilled person may appreciate, the use of finer fibres increases production costs. It has been found that animal wool fibres having a thickness substantially between 15-45 pm and PLA fibres having a Denier measurement substantially between 1 -8 D provided a substantially even dispersion of the different fibre portions and resulted in a board of suitable rigidity.

[0050] I n an embodiment, the thickness of the animal wool fibres may be substantially between 20-35 pm . I n a further embodiment, the thickness of the animal wool fibres may be substantially between 27-32 pm .

[0051 ] I n an embodiment, the PLA fibres may have a Denier measurement substantially between 2-6 D. I n a further embodiment, the substantially- achromatic PLA fibre portion 102 of the PLA fibres in particular may have a denier measurement substantially between 2-4 D.

[0052] I n an embodiment, the fibres of the fibre m ix may have a staple length ( The average length of the longer half of the fibres) of 30-80 mm . It has been found that a m inim um fibre staple length of approx. 30 m m is required in order to ensure that the fibres achieve adequate cohesion within the m ix and thus properly bond together to form the board. A further increase in fibre staple length reduces ‘fibre fall out’ (loss of fibres that occurs during each production stage, most prominent during the blending/opening and carding stages) and thus reduces wastage.

[0053] However, staple length also affects the difficulty in blending the fibres - shorter fibres are dispersed throughout the fibre m ix more easily, while longer fibres more readily ‘tangle’ and so tend to resist the blending process. The effect of staple length on blending difficulty becomes particularly prom inent above approx. 80 m m . I ncreased staple length also increases production costs, as fibres with a longer staple length produce yarns of higher quality.

[0054] I n an embodiment, the PLA fibres of the fibre m ix have a shorter staple length than the anim al wool fibres. I n an example embodiment, the PLA fibres may have a staple length substantially between 50-60 mm , while the animal wool fibres may have a staple length substantially between 55-75 m m .

[0055] I n an embodiment, the substantially- achromatic portion of the PLA fibres may have a shorter staple length than the remainder of the PLA fibres. This may promote improved dispersion of the substantially-achromatic PLA fibres in particular. Without lim iting the scope of the invention through theory, it is considered advantageous in certain situations (depending upon dyes, target colour, etc.) to particularly promote dispersion of the substantially-achromatic PLA fibres. As the substantially-achromatic PLA fibre portion typically makes up only a small proportion of the overall fibre m ix and is achromatic, any 'clumping’ thereof is more noticeable to the casual observer and therefore more readily disrupts the desired marie effect.

[0056] I n an embodiment and with reference to Figure 2, the fibre board 100 may have a surface feature or pattern 108 embossed, impressed or otherwise formed into a surface thereof. I n an embodiment and with reference to Figure 3, the fibre board 100 may be shaped into a particular shape 1 10. I n a further embodiment (not depicted) , the fibre board 100 may both be formed into a particular shape 1 10 and have a surface feature or pattern 108 formed into its surface.

[0057] I n a particular example embodiment, the fibre board 100 may comprise approx. 70% by total weight animal wool fibre and approx. 30% by total weight low melt bicomponent PLA fibre. The animal wool fibre may have a thickness substantially between 27-32 m icron and an average length substantially between 55-70m m , while the PLA fibres may have a thickness substantially between 2-4 D and an average length substantially between 50 - 60m m . The coloured portion of the fibre m ix is substantially comprised of animal wool fibre. The substantially- achromatic portion comprises substantially-white PLA fibres.

[0058] A further aspect of the invention may lie in a method of producing a substantially rigid board that is substantially formed of at least two different types of fibre within a fibre m ix. I n an embodiment, the board may be a board of an embodiment of the previous aspect of the invention. I n a preferred embodiment, the method does not require the addition of an adhesive or further reagent in order to promote bonding or binding between the fibres of the fibre m ix and/or to promote formation thereof into a substantially-rigid board. I n an embodiment and with reference to Figure 4, the method may comprise, in any suitable order, the operations of:

(201 ) opening and blending animal wool fibres and polylactic acid (PLA) fibres into a fibre m ix having a marie-effect colour;

(202) carding the fibre m ix into a fibre web having the marie-effect colour;

(203) cross-lapping the fibre web;

(204) at least one of needle-punching and air-texturing the fibre web; and

(205) compressing the fibre web between heated rollers to form them into the board having the marie-effect colour.

[0059] I n an embodiment, the opening and blending operation 201 may be repeated at least once. This may improve dispersion and mixing of the various portions of the fibre mix, in particular where a colouration means increases the ‘dumpiness’ of the coloured fibre portion.

[0060] I n an embodiment, the compressing operation 205 may be conducted using heated rollers that apply a pressure of at least 600 kPa. I n an embodiment, the heated rollers may have a roller clearance that is 1 mm or less. I n an embodiment, the heated rollers may be heated to a temperature substantially between 150-180°C. I n a further embodiment, the heated rollers may be heated to a temperature substantially between 160-170°C. I n an embodiment, the fibre web may be compressed between the heated rollers at a feed rate that is substantially between 0.5-3 m/min. I n a further embodiment, the feed rate may be substantially between 1 -2 m/m in.

[0061 ] I n an embodiment and with reference to Figure 5, the punching/ texturing operation 204 may comprise needle-punching. I n such an embodiment, the operation 204 may comprise a first needle-punching sub-operation 204a conducted on one side of the fibre web followed by a second needle-punching suboperation 204b being conducted on a second, opposing side of the fibre web. This may be in addition to or instead of an air-texturing sub-operation (not depicted) . I n an embodiment wherein the air-texturing sub-operation is also performed, said sub-operation may be before, between, or after the first and second needlepunching sub-operations.

[0062] I n an embodiment and with reference to Figure 6, the method may further comprise a heating operation 205a, wherein the fibre web is heated prior to being compressed between heated rollers. I n an embodiment, the fibre web is heated for substantially between 80 to 1 10 seconds. I n an embodiment, the heating operation 205a) is executed within an oven having a temperature substantially between 140- 170 °C. I n a further embodiment, the oven temperature may be substantially between 150- 160°C. I n an embodiment, the compressing operation 205 conducted using heated rollers may enable fibres within the fibre web to at least partially melt. Said at- least-partially molten fibre, upon resolidifying, may attach, adhere or otherwise bind to other fibres proximal thereto within the fibre web. This may increase the fibre web’s rigidity and cohesion and thereby form it into a rigid board without the use of adhesives or other reagents.

[0063] I n some embodiments, it may be necessary to maintain compression of the heated and compressed fibre web during at least a portion of the cooling and solidifying process so as to promote binding between at- least-partially molten fibres and other fibres nearby. I n such an embodiment and with reference to Figure 7, the compressing operation 205 may be a heated compressing operation 205 which produces a heated fibre web. The method may further comprise a cooling compressing operation 206 comprising compressing the heated fibre web between cooling rollers. The cooling compressing operation 206) may serve to draw heat out of the heated fibre web, allowing any melted or partially-melted fibres to resolidify and bind with other fibres, while inhibiting the fibre web from decompressing or expanding.

[0064] I n an embodiment, the cooling compressing operation 206 may be conducted using cooling rollers that apply a pressure of at least 600 kPa. I n an embodiment, the cooling rollers may have a roller clearance that is 1 m m or less. I n an embodiment, the fibre web may be compressed between the cooling rollers at a feed rate that is substantially between 0.5-3 m/m in. I n a further embodiment, the feed rate may be substantially between 1 -2 m/m in. I n an embodiment, the cooling rollers may be rollers designed, arranged, configured or otherwise adapted to draw heat out of the heated web being fed therethrough. I n a further embodiment, the cooling rollers may be air- or water-cooled. I n an alternate further embodiment, the cooling rollers may be cooled by a refrigerant or other means known in the art of reducing temperature to below ambient.

[0065] It may be desirable to either form a pattern or other surface feature onto a surface of the produced fibre board, or to form the fibre board into a particular shape. I n such a scenario and with reference to Figure 8, an embodiment of the method may further comprise a shaping operation 207, wherein the board is thermoformed into a desired shape, a surface feature is embossed, impressed or otherwise formed into a surface of the board, or both.

[0066] I n an embodiment, the shaping operation is conducted at an operating pressure substantially between 5-8 MPa. I n a further embodiment, the operating pressure may be substantially between 6-7.5 MPa. I n an embodiment, the shaping operation is conducted using a shaping tool. I n a further embodiment, the shaping tool is unheated. I n an embodiment, the shaping tool may be a m ulti-part tool that compresses and shapes the fibre board between two or more parts. The shaping tool may be a mould having at least a male component and a complementary female component.

[0067] Some fibre m ixes require that a shaping operation be conducted while the fibre board is at an elevated temperature, even if the shaping tool is unheated. I n an embodiment, the shaping operation may be conducted while the fibre board is at a temperature substantially between 150- 170°C. I n a further embodiment, the shaping operation may be conducted while the fibre board is at a temperature of approximately 160°C. I n an embodiment, the method may comprise feeding the fibre board which is output from the heated rollers employed in the compressing operation 205 directly into the shaping operation 207.

[0068] I n some embodiments, the fibre board may require temperature adjustment prior to being shaped. I n such an embodiment the shaping operation 207 may be preceded by a temperature-adjustment operation 207a which may comprise heating or cooling the fibre board to an appropriate temperature for shaping. The employment of a temperature-adjustment operation 207a may be necessary if - as a non-lim iting example - the fibre board is output from the heated rollers following compressing operation 205 at a temperature that is either unsuitable for, or not conducive to, shaping. The employment of a temperatureadjustment operation 207a may also be necessary if - as a further non-lim iting example - a cooling compression operation 206 is also employed.

[0069] I n an embodiment, the board is allowed to at least partially cool during the shaping operation to enable the board to ‘set’ having the applied shape.

[0070] While the invention has been described with reference to preferred embodiments above, it will be appreciated by those skilled in the art that it is not lim ited to those embodiments, but may be embodied in many other forms, variations and modifications other than those specifically described. The invention includes all such variation and modifications. The invention also includes all of the steps, features, components and/or devices referred to or indicated in the specification, individually or collectively and any and all combinations or any two or more of the steps or features.

[0071 ] I n this specification, unless otherwise explicitly identified, the various embodiments of the invention are not to be regarded as being exclusive of one another.

[0072] I n this specification, unless the context clearly indicates otherwise, the word “comprising” is not intended to have the exclusive meaning of the word such as “consisting only of”, but rather has the non-exclusive meaning, in the sense of “including at least”. The same applies, with corresponding gram matical changes, to other forms of the word such as “comprise”, etc.

[0073] I n this specification, unless the context clearly indicates otherwise, the word “substantially” in connection with a technical feature, property thereof, or other term , is intended to impart the meaning of “in substance” thereto, in that said technical feature, property thereof, or other term is achieved to sufficient degree and/or with sufficient precision to achieve the scope, object or purpose of the invention or particular embodiment, and so said technical feature, property thereof, or other term so qualified is to be interpreted to include m inor variances that fall outside of the literal definition thereof, yet would be understood by the person skilled in the art to have negligible effect on the working of the invention. The same applies, with corresponding grammatical changes, to other forms of the word.

[0074] Other definitions for selected terms used herein may be found within the detailed description of the invention and apply throughout. Unless otherwise defined, all other scientific and technical terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which the invention belongs.

[0075] Any prom ises made in the present document should be understood to relate to some embodiments of the invention, and are not intended to be prom ises made about the invention in all embodiments. Where there are prom ises that are deemed to apply to all embodiments of the invention, the applicant/patentee reserves the right to later delete them from the description and they do not rely on these prom ises for the acceptance or subsequent grant of a patent in any country.

Claims

CLAI MS

1 . A substantially rigid and homogenous board substantially formed of a m ix of fibres in a non-woven state, wherein: the fibre m ix comprises from about 50% to about 70% by weight animal wool fibres, and from about 30% to about 50% by weight polylactic acid (PLA) fibres; the animal wool fibres have a thickness substantially between 15-45 pm ; the PLA fibres have a denier measurement substantially between 1 - 8 D; at least a portion of the PLA fibres are substantially achromatic; at least one portion of the non-woven fibres are coloured; and the fibres of the fibre m ix are dispersed such that the board exhibits a marie-effect colour, the marie-effect colour being a combination of colours of at least the substantially achromatic PLA fibre portion and the or each coloured non-woven fibre portion.

2. The board of claim 1 , wherein the substantially achromatic PLA fibre portion are substantially black or substantially white.

3. The board of claim 1 or claim 2, wherein the substantially achromatic PLA fibre portion comprise less than about 10% by total weight of the fibre m ix.

4. The board of claim 3, wherein the substantially achromatic PLA fibre portion comprise from about 3% to about 5% by total weight of the fibre m ix.

5. The board of any one of the above claims, wherein the substantially achromatic PLA fibre portion comprises PLA fibres having a thickness of about 2 D.

6. The board of any one of the above claims, wherein the or each coloured fibre portion are: a further portion of the PLA fibres; a portion of the animal wool fibres; or a combination thereof.

7. The board of claim 6, wherein there are at least two coloured fibre portions that are different colours.

8. The board of any one of the above claims, wherein the thickness of the animal wool fibres is substantially between 20-35 pm .

9. The board of claim 8, wherein the thickness of the animal wool fibres is substantially between 27-32 pm .

10. The board of any one of the above claims, wherein at least a portion of the PLA fibres are low melt PLA fibres.

1 1 . The board of claim 10, wherein the low melt PLA fibres are bicomponent low melt PLA fibres.

12. The board of any one of the above claims, wherein the fibres of the fibre m ix have a staple length of 30-80 mm .

13. The board of any one of the above claims, wherein a portion of the fibres of the fibre m ix are not coloured; such that the marie-effect colour is a combination of colours of at least the substantially achromatic PLA fibre portion, the or each coloured fibre portion, and the non-coloured fibre portion.

14. The board of any one of the above claims, having a thickness between 5- 15 m m .

15. A method of producing the board of any one of claims 1 -14, comprising, in any suitable order, the operations of: opening and blending animal wool fibres and polylactic acid (PLA) fibres into a fibre m ix having a marie-effect colour; carding the fibre m ix into a fibre web; cross-lapping the fibre web; at least one of needle-punching and air-texturing the fibre web; and compressing the fibre web between heated rollers.

16. The method of claim 15, wherein the operation of opening and blending the animal wool fibres and PLA fibres is repeated at least once.

17. The method of claim 15 or 16, wherein the heated rollers compress the fibre web with a pressure of at least 600 kPa.

18. The method of any one of claims 15- 17, wherein the heated rollers have a roller clearance that is 1 mm or less.

19. The method of any one of claims 15-18, wherein the fibre web is compressed between the heated rollers at a feed rate between 0.5-3 m/m in.

20. The method of any one of claims 15- 19, wherein the heated rollers are heated to a temperature between 150-180°C.

21 . The method of claim 20, wherein the heated rollers are heated to a temperature between 160-170°C.

22. The method of any one of claims 15-21 , wherein the fibre web is needle- punched; and the operation of needle-punching is conducted at least twice; a first needle-punching being conducted on one side of the fibre web; and a second needle-punching being conducted on a second, opposing side of the fibre web.

23. The method of any one of claims 15-22, further comprising the operation of heating the fibre web prior to compressing the fibre web between heated rollers.

24. The method of claim 23, wherein the fibre web is heated within an oven having a temperature between 140- 170°C.

25. The method of claim 24, wherein the oven temperature is between 150- 160°C.

26. The method of any one of claims 23-25, wherein the fibre web is heated for 80- 1 10 seconds.

27. The method of any one of claims 15-26, further comprising, after the operation of compressing the fibre web between heated rollers, the operation of compressing the fibre web between cooling rollers.

28. The method of claim 27, wherein the cooling rollers compress the fibre web with a pressure of at least 600 kPa.

29. The method of claim 27 or 28, wherein the cooling rollers have a roller clearance that is 1 m m or less.

30. The method of any one of claims 27-29, wherein the fibre web is compressed between the cooling rollers at a feed rate between 0.5-3 m/m in.

31 . The method of any one of claims 15-30, further comprising a shaping operation of:

(a) thermoform ing the fibre board into a desired shape; or

(b) embossing, impressing or otherwise form ing a surface feature into a surface of the fibre board; or

(c) both thermoform ing and embossing, impressing or otherwise form ing the surface feature into the surface of the fibre board.

32. The method of claim 31 , wherein the shaping operation is conducted at an operating pressure substantially between 5-8 MPa.

33. The method of claim 31 or 32, further comprising conducting a temperature adjustment operation prior to the shaping operation.