GB2516859A

GB2516859A - Fibres

Info

Publication number: GB2516859A
Application number: GB1313800.3A
Authority: GB
Inventors: Andrew Starkey; Carl Antony Rushton; Kirill Horoshenkov; Anton Vladimirovich Krynkin
Original assignee: John Cotton Group Ltd
Current assignee: John Cotton Group Ltd
Priority date: 2013-08-01
Filing date: 2013-08-01
Publication date: 2015-02-11
Also published as: GB201313800D0; WO2015015214A1

Abstract

The sound attenuation material comprises a first proportion of fibres 10 and a second proportion of fibres 20. Each fibre in the first proportion of fibres 10 has substantially the same linear mass density as the other fibres in the first proportion of fibres 10. The linear mass density of the first fibres 10 = 0.1-25 (4-5) dtex. Each fibre in the second proportion of fibres 20 has substantially the same linear mass density as the other fibres in the second proportion of fibres 20. The linear mass density of the second fibres 20 is preferably = 5-30 (12-18) dtex and at least 2 dtex greater than the linear mass density of the first fibres 10. The fibrous layers 10, 20 are preferably nonwoven material comprising hollow, composite, polyethylene, polyester, polyurethane, cotton or wool fibres. The acoustic absorbing material is preferably sealed within a woven fabric. Such materials and products are used in or for bedding materials or other soft furnishings.

Description

Fibres The present invention relates to fibrous material, particularly fibrous material for acoustically treating a room or environment, for example, by reducing the level of noise in the room or environment or otherwise altering at least one property of one or more sound waves in the room or environment.

Unwanted, or undesirably high levels of, noise is an everyday problem in a wide variety of environments. The noise may be generated externally from the environment and transmitted thereto and/or may be generated in the environment itself. Typically the person or persons disturbed by the noise is not responsible for generating it and may not be able to prevent the noise being generated and may have little or no control over the level of the noise. One environment where noise can be particularly disturbing is the bedroom, where loud or persistent noise can prevent a person from being able to sleep and/or may be sufficiently disturbing to wake a person who has managed to fall asleep.

Whilst noise generated outside the bedroom, such as noise from other rooms in the house, noise from neighbouring houses, traffic noise and other external noise, etc., may be sufficient to disturb the person trying to sleep, a more local source of noise is often more troublesome due to its intensity, proximity and disruptive nature -the noise of another person in the bedroom who is asleep and snoring. Whilst the person being disturbed by the snoring could alleviate the problem by waking up the snorer, it is often the case that the snorer simply begins snoring again as soon as they fall back to sleep, leading to a restless, frustrating and unpleasant night for the person kept awake by the noise as well as disrupting the sleep of the snorer if they are repeatedly awoken. The bedroom scenario is just one example of the many different environments in which the presence of noise, or of high levels of noise, can be disturbing and undesirable.

It is therefore desirable to provide means for reducing the level of noise in an environment, for example near a sleeper and a snorer. In accordance with the present invention! from a first broad aspect, there is provided a material comprising a first proportion of fibres, each fibre in the first proportion of fibres having substantially the same linear mass density as the other fibres in the first proportion of fibres, the linear mass density of the first fibres being in the range of 0.1 to 25 dtex; and a second proportion of fibres, each fibre in the second proportion of fibres having substantially the same linear mass density as the other fibres in the second proportion of fibres, the linear mass density of the second fibres preferably being at least 2 dtex greater than the linear mass density of the first fibres and being in the range of 5 to 30 dtex, wherein the material is configured to attenuate sound waves in the vicinity of the material.

Thus there is provided a material that has a least two sets of fibres each of a particular configuration so that when combined, the material is capable of reducing the sound pressure in a wave emitted by a source which is placed in the vicinity of the material. Without intending to be bound by theory, it is believed that this is achieved because the material has a porous structure that is tuned to attain a particular value of the acoustic surface admittance which enables (i) the absorption of the energy in the incident sound wave which passes through the material to be maximised; (U) the destructive interference effect which takes place between the incident sound wave and the sound wave reflected from the material to be maximised; and (Ui) the shape of the material surface to be tuned to maximise the above two effects in the desired frequency range. The combination of the fibres of which the material is composed can be tuned to maximise the sound attenuation in the frequency range in which the amplitude in the sound pressure emitted by the source is particularly high and appears disturbing to the sleeper. Thus two acoustic phenomena which are observed when a fibrous material is present in this environment (visco-thermal absorption and destructive interference effects) can be maximised by tuning the fibrous material micro-structure, the thickness of the fibrous layer and its shape. Near field attenuation of sound (i.e. attenuation of sound at the source of the sound) can be achieved using the material of the present invention, which is particularly advantageous in scenarios where a person in a room such as a bedroom would be disturbed by a noise generated elsewhere in the room, particularly from another person who is asleep and snoring. Attenuating sounds near the sound source (e.g. where the snorer is snoring) reduces the level of noise detected by another person near to the source and may prevent the other person from being disturbed.

Without intending to be bound by any particular theory, it is believed that combining a first proportion of fibres (whore the fibres all have substantially the same linear mass density) and a second proportion of fibres (where the fibres all have substantially the same linear mass density, the linear mass density preferably being at least 2 dtox greater than that of the first proportion of fibres) provides a material that is not only soft, compliant and (where used in, e.g., soft furnishings, bedding or the like) comfortable, but also provides much higher attenuation in the sound wave propagating in the vicinity of this material compared with other typical materials. If only fibres of the first proportion of fibres were used, the linear mass density of the fibres should provide a soft, compliant and comfortable material but the sound attenuating properties would be insufficient to significantly reduce the amplitude of a disturbing sound wave. If only fibres of the second proportion of fibres were used, the linear mass density of the fibres should provide a material that has good sound attenuating properties but would be uncomfortable, less compliant and not soft. However by combining at least two proportions of such fibres having different linear mass densities (the difference preferably being at least 2 dtex) it has been found that a synergistic effect of good sound attenuation and softness, compliance and comfort is provided.

Each fibre in the first proportion of fibres has substantially the same linear mass density as the other fibres in the first proportion of fibres. Namely the first proportion of fibres consists of individual fibres where each of the individual fibres has the chosen linear mass density. For example, if the linear mass density of the first proportion of fibres is, say, 5 dtex, then each individual fibre in the first proportion of fibres will have a linear mass density of 5 dtex.

Each fibre in the second proportion of fibres has substantially the same linear mass density as the other fibres in the second proportion of fibres. Namely the second proportion of fibres consists of individual fibres where each of the individual fibres has the chosen linear mass density. For example, if the linear mass density of the second proportion of fibres is, say, 15 dtex, then each individual fibre in the second proportion of fibres will have a linear mass density of 15 dtex.

Within the meaning of the present invention, statements that a fibre has a particular linear mass density means that the fibre is manufactured to have the desired linear mass density within manufacturing tolerances, i.e. within about +1-20 percent of the stated linear mass density. Measurement of the linear mass density is in accordance with usual practices within the industry, for example using either a video microscope or a projection microscope, to measure the fibre thickness in microns and calculating the dtex based on the thickness. Such methods are accurate and readily replicatable with a calibrated microscope, e.g. calibrated with a stage graticule.

The linear mass density of the first proportion of fibres is lower than the linear mass density of the second proportion of fibres, so that the first proportion of fibres provides softness and the second proportion of fibres provides resilience and sound attenuation. The linear mass density of the second proportion of fibres is preferably at least 2 dtex greater than the linear mass density of the first proportion of fibres. The linear mass density of the second proportion of fibres may be at least 2.5 dtex greater than the linear mass density of the first proportion of fibres, and may be at least 5 dtex greater and may be at least 7.5 dtex greater and may be at least 10 dtex greater than the linear mass density of the first fibres. The difference in linear mass density between the first and second proportion of fibres can be selected based on certain criteria such as the application of the material, the level of sound required to be attenuated, the frequency of sound required to be attenuated, the size and/or shape or other configuration of the material, etc. The linear mass density of the first proportion of fibres is in the range of 0.1 to 25 dtex, and may be in the range of 1 to 10 dtex, and may be in the range of 2 to 8 dtex, and may be in the range of 3 to 7 dtex, and may be in the range of 4 to S dtex. The linear mass density of the second proportion of fibres is in the range of 5 to 30 dtex, and may be in the range of 5 to 25 dtex, and may be in the range of 10 to 20 dtex, and may be in the range of 12 to 18 dtex, and may be in the range of 14 to 16 dtex. Such ranges provide fibres with a variety of advantageous softness, compliance, resilience and sound attenuating properties, depending on the application, material dimension and the like.

The sound attenuating properties of the material may depend on the diameter, proportion and/or the linear mass density of the fibres in the first and second proportion of fibres. The material may be configured to attenuate sound waves passing into the material so as to reduce the sound pressure level of the sound wave which is affected by the presence of the material (i.e. the sound wave a part of which energy has been absorbed by the material and another part has been reduced because of the destructive interference between the incident wave and the wave reflected by the material) by at least I dB compared with the sound pressure level of the incident sound wave (i.e. the sound wave before it is affected by the material). The material may be configured to attenuate sound waves passing into the material so as to reduce the sound pressure level of the outgoing sound wave by at least 2 dB compared with the sound pressure level of the incident sound wave, and may attenuate the sound waves by at least 4 dB and may attenuate the sound waves by at least 6 dB and may attenuate the sound waves by at least 8 dB compared with the sound pressure level of the incident sound wave. By attenuating sound by these amounts advantageous materials are provided that have many applications, for example in bedding materials and/or other soft furnishings for rooms such as the bedroom in which external and/or internal noise can be detrimental to a person attempting to sleep, particularly noise such as another person's snoring. A reduction of 2 to 8 dB or more of the noise generated by a typical snorer is a significant reduction and may be the difference between the disturbed person being able to sleep/remain asleep or not.

The material may be configured to attenuate sound waves having a frequency in the range of 100 to 1600 Hz, and may be configured to attenuate sound waves having a frequency in in the range of 300 to 1200 Hz, and may be configured to attenuate sound waves having a frequency in the range of 500 to 1000 Hz. Sound waves having frequencies in the ranges can be generated by a variety of means and, for example, a snoring person may generate noise having such frequencies, for example in the range of 500 to 1000 Hz in some cases. Therefore attenuating such frequencies is advantageous, particularly for use in attenuating noise such as snoring.

The fibres in the first and second proportion of fibres can be any suitable fibres.

The first fibres may comprise synthetic fibres, and may be polyester fibres or polyethylene fibres or polyurethane fibres or the like. Alternatively the first fibres may comprise natural fibres, and may comprise cotton fibres or wool fibres or the like.

Alternatively the first fibres may comprise some synthetic fibres and some natural fibres, i.e. a mixture of fibre types. The second fibres may comprise synthetic fibres, and may comprise polyester fibres or polyethylene fibres or polyurethane fibres or the like.

Alternatively the second fibres may comprise natural fibres, and may comprise cotton fibres or wool fibres or the like. Alternatively the second fibres may comprise some synthetic fibres and some natural fibres, i.e. a mixture of fibre types. Either or both of the first and second fibres may comprise bicomponent fibres. Either or both of the first and second fibres may comprise hollow fibres. Any of the above fibres may be suitable for use for the material of the present invention depending on the properties required for the material.

The material comprises a first proportion of first fibres and a second proportion of second fibres. The material may consist of only the first and second proportions of fibres, namely the first proportion of fibres combined with the second proportion of fibres may form substantially 100% of the material. Alternatively the first proportion of fibres combined with the second proportion of fibres forms less than 100% of the material, with the remainder of the material comprising at least one of synthetic fibres, natural fibres, feathers and down. The remainder of the material may comprise at least one of goose down, duck down, goose feathers and duck feathers. As an example, it may be desirable to include other such fibres or the like to enhance a particular property of the material such as softness for, e.g., bedding by adding, e.g., feathers or down, etc. The proportion of first fibres does not need to be the same as the proportion of second fibres. Namely there could be more of the first or second fibres than of the second or first fibres respectively. Alternatively the proportion of first fibres may be substantially the same as the proportion of second fibres, i.e. the proportion of first fibres may comprise about 50% of the material and the proportion of second fibres may comprise about 50% of the material. However the proportion of first fibres may comprise anywhere in the range of about 5 to 95% of the material, preferably about 20 to 80% of the material, preferably about 35 to 65% of the material, and the second fibres may comprise anywhere in the range from about 5 to 95% of the material, preferably about 20 to 80% of the material, preferably about 35 to 65% of the material.

The material can be of any suitable configuration and may Gomprise a graded porous structure which is tuned to provide both the comfort and high sound attenuation.

For example the first fibres could be randomly or regularly and/or loosely mixed with the second fibres or the first fibres could be arranged in a pattern relative to the second fibres. The material can incorporate larger voids in the form of meso-pores. For example.

the first fibres could be arranged in an agglomerate with or without voids or in agglomerates with an agglomerate or agglomerates of the second fibres interposed between the agglomerate(s) of first fibres, or vice versa. Such an arrangement in, for example, a pillow could have the first fibres generally in the centre of the pillow for comfort and the second fibres generally at either end of the pillow, where there is less compression from the head of person using the pillow, for sound attenuation.

The first fibres may be formed into a nonwoven fabric. The second fibres may be formed into a nonwoven fabric. This is advantageous because the fabric may be easier to handle and/or to form into a product when it is in the form of a nonwoven compared with, e.g., a loose mass of fibres. The nonwoven fabric(s) may be formed by carding, which provides a fabric that is easy to handle and has desired properties. The nonwoven fabric may be a vertically lapped nonwoven. This is advantageous because the fabric can be made to desired dimensions, is easy to handle, is high loft and the vertical orientation of the fibres provides a relatively uniform product that is resilient and has great recovery from compression. Such vertically lapped nonwovens can be manufactured from a wide range of natural, synthetic, recycled and blended fibres at various web weights and product densities. Not only are such materials desirable for the properties discussed previously (including softness, comfort and sound attenuation) but also can be configured to provide support and are useful for orthopaedic applications, e.g. support pillows, mattress toppers, mattresses and the like for reducing or eliminating discomfort for a sleeper.

The first fibres andlor the second fibres may be formed into a plurality of ball fibres.

The material may comprise at least one of a random, an ordered and a regular mixture of the first ball fibres and the second ball fibres. Ball fibres are advantageous because they can provide softness and comfort but are also resilient and useful in applications such as soft furnishings, particularly bedding materials.

As discussed above, the fibres can be loose fibres or can be formed into a fabric or the like. The first fibres may be are formed into a first web or batt and/or the second fibres may be formed into a seGond web or batt. Having the fibres formed into a web or batt aids handling and provides integrity to the structure. The first web or batt may be separately provided from the second web or batt and a layered structure may be formed by overlaying one of the first and second web or batt on the other of the first and second web or batt. This enables a structured, layered product to be provided, which is advantageous for some applications and provides a material with and ordered arrangement of the first fibres relative to the second fibres. With a material in which the first web or batt is overlaid onto the second web or batt, the layered structure may be rolled about an axis that is substantially parallel with a first axis of the plane of the layered structure to form a generally cylindrical rolled structure, wherein the first fibres form the inner surface of the rolled structure and the second fibres form the outer surface of the rolled structure. Namely the two stacked layers are rolled up to form a "Swiss roll" type layered arrangement preferably with pore stratification. This can be particularly advantageous in some applications because the structure can be readily configured to provide the synergistic softness, comfort and sound attenuation as required and is easily adjusted by, for example, changing the thicknesses of one or both layers, or the tightness of the rolling, or the density of the fibres in one or both layers, etc. Whilst a Swiss roll is usually generally cylindrical, the cross section of the structure may be generally circular, or may be elliptical (for example if the material is relatively soft or compliant or the roll is not tightly wound, etc., it may take an elliptical shape.

Alternatively the cross-section may be rectangular, formed for example more by folding of the layers than rolling. The configuration can be adapted to the intended use of the finished product.

The material is not restricted to being restricted just two layers and one or more further layers could be added prior to rolling the structure. Thus the material may comprise at least one further proportion of fibres formed into a third web or batt, the third web or batt being overlaid onto the layered structure such that when the layered structure is rolled about the axis, the third web or batt forms either the inner surface or the outer surface of the rolled structure. The third web or batt may comprise the same fibres as the first fibres or the same fibres and the second fibres or may comprise different fibres from either the first or second fibres. Therefore some structures may comprise alternate layers of first and second fibres (having a plurality of one or both of these layers) or may comprise alternating layers of first, second and third fibres (having a plurality of one, two or three of these layers) or may comprise more than three layers in any combination, etc. Thus there is provided a highly configurable material having a variety of different properties that can be selected for the desired end product.

Prior to rolling a structure as discussed above, a block of fibres or foam material may be laid onto the structure such that when the structure is rolled about the axis, the block forms a central portion of the rolled structure. It is possible that the block could be formed of the first fibres in which case the structure may comprise just a single layer of the second fibres and thus the material is formed as a composite structure with the first fibres forming a central core of a composite structure and the second fibres forming an outer core of a composite structure being rolled or wrapped around the block of first fibres with or without a void in the centre. This arrangement is more like a "sausage roll" than a "Swiss roll" and may be useful, for example, when forming a supportive structure such as an orthopaedic pillow, because the block can provide the necessary support as well as the softness. The block may be formed as a vertical lapped nonwoven.

Alternatively, the block may comprise the first or the second or different fibres (for example formed as a vertically lapped nonwoven or the like) or may be a foam material or other suitable block. In this arrangement, the Swiss roll is formed from two (or more) layers (of at least one layer of first fibres and one layer of second fibres) rolled around a block or a void at the core. Without intending to be bound by any particular theory, it is believed that arrangements with the softer (i.e. lower linear mass density) fibres inside the coarser (i.e. higher linear mass density) fibres is particularly advantageous because the more resilient outer fibres allow the sound to pass into the central portion of the material where the softer fibres have a greater air resistance and trap' the sound. The inner fibres attenuate the sound by not only absorbing some of the sound energy (and converting it to heat) but also scattering the sound wave and altering the sound pressure.

Thus the synergy that is believed to occur when such fibres are combined may be enhanced further by arrangements having the softer fibres inside the central portion of the material.

The material of the above embodiments has many different uses. Soft furnishings, particularly bedding and related products, have been discussed above and in such applications (and indeed in other applications) it is often desirable to provide a product incorporating the material of the embodiments encased in an outer casing for ease of handling and for product durability, etc. Therefore from a further broad aspect, in aGcordance with the present invention, there is provided a tilled product comprising a casing, the casing preferably comprising a woven fabric, and the material as claimed in any one of the preceding claims, wherein the material is sealed inside the casing so as to form the filled product. For example, in the case of a pillow made from the material of the embodiments of the present invention, it is desirable for the pillow fibres to be encased in a covering or pillow tick. Other arrangements are possible and, for example, the product may comprises at least one of the following: a pillow, a duvet, a mattress, a mattress topper, a lined curtain, a valance, a pelmet, a headboard padding or cover, a wall hanging, carpet underlay, insulation, or the like. Any one of these or indeed other products may benefit from the material being encased in an outer casing. In the case of a mattress, particularly a mattress for a cot or other bedding on which a baby or child might sleep, the outer casing can be important because the baby might not be able or advised to be sleeping with a pillow and thus the comfort of the mattress can be enhanced with the cover. Furthermore the sound attenuating properties of the cot mattress can reduce the level of noise at source if the baby sleeping on the mattress wakes and begins to cry, but the mattress can be configured such that the sound is only attenuated to a level that is acceptable and less distressing to the person caring for the baby but that can still be heard so that the carer is able to determine if the baby needs -10-attention.

As the sound attenuating properties of the material at least in part depend on the sound wave passing into the material as well as reflecting from the material, the casing should be configured so as not to prevent or hinder this from happening to any detrimental level. Therefore the casing may comprises an open woven fabric, and may comprise woven fibres selected from cotton, nylon, wool, rayon, polyester, etc. For example, the tick may comprise polyester and cotton, with for example 52/48% polyesterlcotton content. Woven fabrics are advantageous because the relatively open pores of the weave allows the sound waves to be attenuated to pass into the material and thus the fibres can be effective at absorbing the sound. Without intending to be bound be any particular theory, it is believed that very tightly woven fabrics or other fabrics that have only very small or no pores may hinder the performance of the fibres in attenuating sound to some degree, perhaps because the sound wave may at least partially reflect or scatter from the outer casing rather than passing sufficiently into the material and to the fibres to be very effective.

As discussed above, advantageously there is provided a material with fibres configured for many properties, for example comfort, softness and sound attenuation, which can be formed into a product such as those discussed above. From a further broad aspect, in accordance with the present invention, there is provided a method of forming a filled product for attenuating a sound wave, the method comprising determining a linear mass density for a first proportion of first fibres within the range of 0.1 to 25 dtex, determining a linear mass density for a second proportion of second fibres within the range of 5 to 30 dtex, determining the first proportion of first fibres, the second proportion of second fibres and the proportion of other material in the product where the first proportion plus the second proportion does not equal substantially 100%.

Thus there is provided a method of configuring a filled product to a particular requirement based on a number of factors such as desired sound attenuating properties and desired softness, comfort, support and the like. This may be particularly advantageous when applied to, e.g., soft furnishings and in particular bedding because a person wishing to obtain a, e.g., pillow for a particular noise attenuation requirement (for example a particular level and/or frequency of noise such as snoring) can determine the properties required for the fibres and a custorriised product may be provided.

As discussed above, bedding products and other soft furnishings, particularly those for use in a bedroom, are particularly advantageous for providing a peaceful environment in which to rest or sleep. Other products are also advantageous and indeed other soft furnishings or materials used outside the bedroom for personal and/or industrial use, such as heat and/or sound insulation, cushioning or padding for seats, etc., are also advantageous when provided in accordance with the present invention. It has been found that a particularly advantageous embodiment of the present invention is provided having certain fibres and therefore, from a further broad aspect, there is provided a material comprising a first proportion of fibres, each fibre in the first proportion of fibres having substantially the same linear mass density as the other fibres in the first proportion of fibres, the linear mass density of the first fibres being in the range of 4 to 5 dtex, and a second proportion of fibres, each fibre in the second proportion of fibres having substantially the same linear mass density as the other fibres in the second proportion of fibres, the linear mass density of the second fibres being in the range of 12 to 18 dtex, wherein the material is configured to attenuate sound waves passing through the material so as to reduce the sound intensity level of an outgoing sound wave, the outgoing sound wave having travelled through the material, by at least 5 dB compared with the sound intensity level of an incoming sound wave, the incoming sound wave being the sound wave before it passes into the material.

Embodiments of the present invention will now be described, by way of example only and with reference to the accompanying drawings, in which: Figure 1 schematically illustrates a material comprising at least two layers of fibres in accordance with embodiments of the present invention; Figure 2 schematically illustrates the material of figure 1, formed into a "Swiss roll" rolled structure; Figure 3 schematically illustrates another material in accordance with embodiments of the present invention comprising at least two layers of fibres and a block overlaying the fibre layers; Figure 4 schematically illustrates the material of figure 3, formed into a "Swiss roll" rolled structure with the block or void forming the central core; Figure 5 schematically illustrates another structure in accordance with embodiments of the present invention comprising a central core of fibres or void and an outer layer of fibres, formed into a "sausage roll" structure; -12-Figure 6 illustrates the sound level spectrum of a typical snore; Figure 7 illustrates the sound attenuating properties of several different fibre types and of a material in accordance with embodiments of the present invention; and Figure 8 illustrates the ieduction of snoring obtained for the fibre types and material of figure 7.

A material 2 in accordance with embodiments of the present invention is illustrated schematically in figure 1. A first proportion of first fibres 10 is provided in this embodiment as a nonwoven layer formed by carding, but any other suitable methods of forming fibres into a layer could instead be used. A second proportion of second fibres 20 is also provided as a carded nonwoven layer. In this embodiment, the first fibres 10 form about 50% of the material and the second fibres form about 50% of the material.

Whilst not visible in the figures, in this embodiment the first fibres 10 each have a linear mass density of about 4.4 dtex and the second fibres each have a linear mass density of about 16.7 dtex (15 denier). The layer of first fibres 10 is laid on top of the layer of second fibres 20 to form a layered structure.

The material 2 is rolled into a "Swiss roll" structure as shown in figure 2. To form the rolled structure, the two layers 10, 20 are rolled together by turning the layer of first fibres 10 back on itself and the second layer of fibres 20 with it to form a structure in which the inner core is hollow and its surface is formed by the first fibres 10 and the outer surface is formed by the second fibres 20. The rolled structure is suitable for use as a pillow, for example and the rolled structure may therefore be inserted into a pillow tick or other casing and sealed therein to form the finished pillow. The pillow is particularly advantageous for use in a bedroom or the like where it is desirable to attenuate noise, such as the noise of a person snoring. The snorer could be the person using the pillow and thus the noise is attenuated at the source (near field attenuation) or another person in the bedroom who would otherwise be disturbed by the snorer could use the pillow, with the sound being attenuated at a distance from the noise source. Ideally, both the snorer and the other person would use such pillows thus increasing the attenuation of the noise.

Figure 3 illustrates an alternative embodiment of the present invention in which layers of fibres 10 and 20 are the same as those illustrated in figures 1 and 2. However an additional layer of fibres is provided as a block 30, which, in this embodiment, is a nonwoven web of fibres formed by vertical lapping. The vertically lapped layer 30 is -13-relatively firm compared with the other layers 10, 20 and provides support and is particularly suited for orthopaedic use, for example. A "Swiss roll" structure is formed from the material 2 as shown in figure 4, with the block 30 forming the core of the roll and the other layers 10, 20 surrounding the block 30, with the outermost surface of the roll being formed by the layer of second fibres 20. In other alternative embodiments (not shown) the block 30 comprises the first proportion of fibres and only one layer of fibres is required, comprising the second proportion of fibres, with the layer of fibres being wrapped around the block to form the material structure.

Figure 5 illustrates another alternative embodiment of the present invention in which a "sausage roll" structure is formed from the material 2. A central core of first fibres 10 is formed and these fibres 10 may form a structure by intertwining or tangling of the fibres, or by being bonded, or the like, or the fibres 10 could be loose and not formed into a structure (for example the fibres 10 could be blown into a casing). A type of fibre that lends itself particularly well to this embodiment is ball fibres, which can be formed and blown into a casing. The casing, as shown in this embodiment, can be formed at least partially by the second proportion of fibres 20. The sausage roll structure could be sealed into an outer casing such as a pillow tick for example.

As discussed above, materials in accordance with embodiments of the present invention advantageously provide soft, compliant and comfortable products that are able to effectively attenuate sound. An example of such a product is a pillow for attenuating noise in the bedroom, particularly noise from a snoring person that might otherwise disturb another person attempting to sleep. Figure 6 shows the sound level spectrum of a typical snore and it can be seen that the noise level is greatest between about 500 and 1000 Hz, reaching a sound pressure level (SPL) of more than 35 dB at these frequencies. Such noise levels could easily disturb another person present in the room where the snorer is sleeping and in fact many people snore at levels higher than the illustration. Therefore the applicant has determined that configuring existing materials in the vicinity of the snorer to significantly reduce the SPL of the snore would be highly advantageous but it is not known what material properties would achieve a sufficient reduction in noise level whilst not interfering with the primary purpose of the product (for example comfort, softness and support in the case of a pillow or a mattress or a mattress topper; warmth, softness and appropriate weight for a duvet; insulation and light reduction for curtains, etc. -14-Figure 8 shows a selection of different fibres and the impact of those fibres on the SPL of the snore of figure 6 when the fibres are made into a pillow (by filling a pillow tick of a 48% cotton, 52% polyester woven fabric). It can be seen that the coarser fibres, i.e. those with a greater linear mass density, have a better tuned surface impedance in the target frequency range of about 500 to 1000 Hz and are therefore expected to be better sound attenuating fibres than those with lower linear mass densities. However, fibres with higher linear mass densities are not suitable for forming many of the products discussed above because they are too coarse and stiff and would not provide the level of softness and comfort required. It has surprisingly been found that by combining fibres of different linear mass densities, it is possible to achieve the desired level of sound attenuation without sacrificing comfort and softness and in fact, without intending to be bound by any particular theory, a synergistic effect may be achieved by such combinations, particularly in certain configurations because the coarser fibres have a lower air resistance and enable sound waves to penetrate into the inventive material where the finer, softer fibres in the centre have a higher air resistance and trap' the sound waves therein, increasing the sound absorption. In addition to this attenuation, the coarser fibres also absorb relatively higher amounts of sound energy that the finer fibres, increasing further the attenuating properties of the material. This is shown in figure 7 in which a material comprising a combination of 50% of fibres having a linear mass density of 4.4 dtex with 50% of fibres having a linear mass density of 15 denier (16.7 dtex) has surface impedance characteristics approaching those of a material comprising only fibres having a linear mass density of 15 or 22 denier (16.7 dtex or 24.4 dtex), and significantly better than those of a material comprising only fibres having a linear mass density of 7 denier (7.8 dtex). It should be noted that typical fibres or feathers from which, e.g., bedding would normally be formed such as grey duck down (GD), white duck down (WD), a complete mixture of fibres in the range of 4 to 15 denier (4.4 to 16.7 dtex) (M) or 5.3 denier (5.9 dtex) fibres have very different sound attenuating properties and are not expected to perform as well as the coarser fibres. Figure 8 illustrates that this is the case. The figure shows the impact of each of the different fibres on the snore of figure 6, when the fibres are formed into a pillow with the tick discussed above. It can clearly be seen that the more traditional pillow materials such as down or fibre mixtures or softer fibres have very little impact on the sound intensity level (SIL) of the snore. Itis only with the coarser fibres, such as the 15 denier (16.7 dtex) dtex or22 -15-denier (24.4 dtex fibres) (which are unsuitable for use in forming a pillow) that a significant reduction in SIL is observed. However, it can be seen that the 4 denier/15 denier (4.4/16.7 dtex) mixture discussed above performs almost as well in reducing the SIL as the 15 denier (16.7 dtex) fibres alone yet the material comprises soft fibres and is suitable for use as a pillow or other bedding material. Namely, little sound attenuating ability is sacrificed whilst still providing a comfortable and soft material that out performs traditional bedding materials and even significantly outperforms a mixture of fibres in the range of 4 to 15 denier (4.4 to 16.7 dtex). Indeed, the SIL is 7 dB lower for the material in accordance with the present invention compared with the mixture of multiple fibres, which (as the decibel is measured on a logarithmic scale) equates to more than a 50% decrease in noise when using the product of the present invention. The data illustrated in figure 7 is given below in table 1.

Whilst the above examples refer to bedding materials such as pillows or duvets, etc., the invention is equally applicable to other products which are typically found in the vicinity of the source of sound or the receiver. For example the product may comprise a liner for a curtain, a headboard padding or cover, a wall hanging, insulation (wall, ceiling or the like) carpet or flooring underlay, etc. A particularly advantageous use of the material is in forming a mattress for a cot or the like, where a pillow would not be used.

Each use of the material can be tailored to the frequency and/or noise level that is desired to be reduced and thus there is provided an advantageous material and method for forming a material that has significant noise attenuating properties yet can still be configured for other desired properties such as comfort, softness, resilience, support, warmth, etc.

Table I

Frequency Surface Impedance by Fibre type (Pa s m1) _________ (Hz) 1.2D 3D 4D 5.3D 7D 15D 1183.591 850.4436 915.6828 883.4086 831.8652 796.3477 1080.151 792.2189 866.7072 831.0206 775.0825 727.3467 1001.176 756.8631 832.5111 789.2952 724.9919 667.5231 920.3113 725.2654 783.566 742.9717 673.417 613.1717 805.352 679.4639 755.6559 717.2926 645.7281 569.5784 738.5866 651.7885 734.4049 694.3062 620.9624 530.7311 686.5349 633.2547 718.9189 676.1247 600.7635 497.4111 645.9378 613.3049 701.0958 659.2604 581.6204 467.0591 621.4851 589.6178 675.2751 643.2066 565.3933 438.5134 -16- 619.4309 567.5147 644.032 630.4311 553.8771 415.3402 210 658.0741 532.9264 598.4872 614.2601 544.4702 393.2058 220 727.3764 479.9569 558.7428 592.1185 536.8382 373.5352 230 807.8145 440.1801 529.1687 555.9262 530.9473 356.7983 240 874.0052 430.5512 509.6705 517.567 525.4296 341.4947 250 909.4071 433.5409 495.3374 481.6454 520.0871 327.4716 260 915.5098 449.7275 499.8749 478.2821 514.6491 317.7563 270 903.9214 461.6864 512.3768 488.7904 504.1368 307.4106 280 891.8794 473.3655 545.8489 498.8214 488.7396 299.6169 290 878.7472 490.689 595.6538 513.649 480.0894 294.2292 300 860.4941 509.2752 626.1473 524.4793 463.3793 289.444 310 842.4364 527.7205 640.3889 535.1012 432.9469 284.9946 320 825.2681 540.8896 648.0377 544.4483 424.7759 278.6509 330 808.3703 547.5507 650.4598 560.7234 447.5883 264.3533 340 790.3599 550.4597 651.8677 588.3876 466.5559 254.4172 350 776.2218 552.922 653.0736 613.7268 493.3322 259.1213 360 763.0624 555.0214 653.5183 623.2459 522.152 266.3948 370 750.1856 560.0297 654.218 625.0426 543.3565 272.8003 380 737.1313 562.3295 650.764 620.8003 552.8545 278.5628 390 730.5029 567.7071 651.1816 620.3753 563.6094 287.7129 400 721.9959 571.5076 648.9247 620.3713 573.9907 299.4087 410 713.1954 576.6007 646.6499 622.7785 581.8737 313.2855 420 704.3164 582.1528 644.3996 626.3871 586.5043 324.987 430 695.3828 587.4616 642.492 631.1973 591.2573 339.4828 440 687.1436 591.2817 640.0531 636.1873 596.1608 355.3579 450 679.4271 593.4709 637.0309 639.4917 600.2892 369.8949 460 672.2467 595.6262 634.3526 639.8894 604.4021 384.5706 470 665.6375 597.8182 631.7329 639.3325 607.9386 400.236 480 658.6623 600.016 628.2592 637.9556 611.6037 415.2004 490 651.0425 603.1016 624.2914 635.7008 614.9672 431.864 500 643.2121 605.8427 620.2744 633.5255 616.925 448.8116 510 634.8859 608.0858 615.8848 631.0189 618.4626 466.5173 520 627.237 609.4807 612.1118 629.1716 620.7862 485.6627 530 620.2835 609.1759 608.6592 626.4361 622.9818 504.4482 540 613.3658 608.356 605.0572 623.0673 626.3173 525.6425 550 607.4628 607.1702 601.7918 619.6504 629.6902 545.9251 560 602.7246 606.0879 599.0921 616.2786 633.526 567.3868 570 598.3832 604.0241 596.1577 612.6063 636.1106 589.0214 580 593.7754 601.3549 593.0691 608.4561 637.7297 612.4372 590 589.5458 598.6891 588.8941 604.1322 637.506 635.3609 600 584.8558 596.3162 584.256 599.7954 636.1644 657.1602 610 581.2817 593.9099 579.2414 595.3752 632.7394 680.9799 620 577.712 591.2778 574.3838 591.191 628.2392 704.127 -17- 630 574.0648 587.3463 569.3074 586.534 623.1369 725.6414 640 571.0495 583.9594 565.4384 582.8263 618.2762 749.2813 650 567.9709 579.6174 561.9986 578.9375 613.2493 766.9541 660 564.1292 574.027 557.5695 573.483 607.3131 784.9468 670 559.3312 567.3412 552.0237 568.0636 600.5921 799.1477 680 555.9697 561.9685 547.3708 563.2908 594.4425 814.3861 690 553.5291 557.7144 543.1007 559.2458 588.2698 827.0595 700 551.8493 553.8286 539.5832 555.9638 582.2755 838.6074 710 549.4978 548.8203 535.1618 552.0647 574.5607 845.62 720 546.8331 543.5805 530.7943 547.8594 567.142 850.3103 730 544.3068 538.8637 526.6205 543.2095 560.054 850.9945 740 541.5343 533.4197 522.1239 538.2448 552.3839 848.8102 750 539.7561 528.9145 518.6453 533.8634 546.3257 844.6789 760 537.0618 523.5454 513.9105 529.0247 539.5807 835.7538 770 535.4881 519.7086 510.9377 524.2736 533.9304 825.3436 780 533.0635 515.2706 507.5906 519.1493 527.5671 812.701 790 530.9933 510.4846 503.8988 513.6163 520.5051 796.1246 800 529.1814 505.9182 500.9874 508.7558 513.3103 777.6518 810 527.6245 501.4864 498.2672 504.9808 507.1729 758.9186 820 525.9611 498.2351 496.5302 501.1192 501.1264 741.3956 830 524.3298 493.258 493.3832 496.9145 493.8258 716.4402 840 523.0179 490.1179 491.7223 494.3735 488.6745 697.2637 850 521.3751 485.7626 489.1053 491.4656 482.027 675.0247 860 520.0528 482.5797 487.6982 488.9828 477.1666 654.7369 870 518.8494 479.634 486.0429 486.9513 471.8567 634.2856 880 516.8682 475.6039 483.2748 483.6776 466.061 611.1528 890 515.4767 472.3562 481.8376 481.432 460.9555 590.0425 900 514.474 470.4557 481.4068 480.3877 457.3647 571.5774 910 513.1335 467.8948 480.3383 478.521 453.01 552.1986 920 511.723 465.7174 479.6628 477.016 449.1643 533.1321 930 510.4032 463.431 478.7251 475.6629 445.2691 514.6313 940 509.1806 461.4311 478.0743 474.6607 442.7988 495.8537 950 508.1316 459.9637 477.5409 474.6173 440.8046 480.1352 960 506.6442 458.2439 477.1352 473.9463 438.5655 463.3459 970 505.4348 456.8607 476.648 473.3954 436.7789 447.9043 980 504.6063 456.3844 476.8538 473.5949 436.1182 434.3138 990 503.6845 456.1045 477.001 474.1686 435.4378 422.0638 1000 501.9156 455.0304 476.5952 473.8533 434.2863 408.1234 1010 500.2788 454.079 476.0073 473.4132 433.3 395.86 1020 498.9676 453.7383 475.9574 473.317 432.8413 384.3621 1030 498.3094 454.3353 476.683 474.1272 433.2585 374.8679 1040 496.6879 453.9837 476.1655 473.9042 432.6577 364.377 1050 495.7034 454.8759 476.9968 475.0125 433.5705 356.9028 -18- 1060 495.0752 456.077 477.702 476.084 434.8045 350.1176 1070 494.2867 457.0371 478.2093 476.74 435.6259 342.9799 1080 493.4503 458.0116 479.0634 477.9067 437.2877 337.9338 1090 492.6889 459.6917 480.2661 479.5161 439.2186 333.6791 1100 491.3995 460.0748 480.2308 479.9297 440.2604 329.5647 1110 487.6753 458.6949 477.9233 478.3202 439.6404 324.2865 1120 484.6006 457.5894 476.2791 477.2434 439.5743 320.9322 1130 483.0208 458.3083 476.1172 477.3985 440.9978 318.5645 1140 484.3078 462.3983 479.2284 480.9576 446.1012 320.4984 1150 484.8949 465.2051 480.8706 483.4223 450.105 322.6533 1160 483.8264 466.3414 481.1315 483.9505 452.5445 323.8762 1170 482.4931 467.556 481.2422 484.6232 454.8544 325.9689 1180 482.1658 469.5461 481.7069 485.7541 458.0812 329.2331 1190 480.741 470.6372 481.719 486.3365 460.492 333.4245 1200 480.2362 472.2098 482.247 487.4818 463.6532 338.139 1210 478.9633 473.3033 481.7638 487.7731 465.8334 343.8577 1220 478.7167 475.137 482.4924 488.6175 468.4549 350.2635 1230 477.6994 476.2288 482.3591 489.5013 470.8813 356.7385 1240 476.3956 477.4939 481.6439 489.5832 472.8678 364.878 1250 475.7406 478.4541 481.8788 490.0833 475.158 372.8542 1260 474.7633 479.7305 481.8133 490.1981 477.4854 381.8049 1270 473.848 480.2723 480.9564 489.9276 478.8683 390.8572 1280 472.8236 480.8817 480.1853 489.7317 480.9655 401.0958 1290 472.4922 481.9125 480.0404 490.1686 483.2844 412.3839 1300 470.7676 481.949 479.0395 488.8374 484.1974 422.6136 1310 470.1094 482.4268 478.3712 488.4947 484.6366 433.9138 1320 469.924 483.3436 477.8144 488.2515 485.738 445.9751 1330 470.0899 484.291 477.6051 488.4648 486.9939 458.7088 1340 470.1033 484.5975 476.812 488.3939 487.8101 471.5223 1350 469.4882 484.4696 476.2271 487.4299 488.3901 484.9656 1360 468.976 484.5411 475.2562 486.5819 488.6263 498.523 1370 468.7184 484.4209 474.3682 486.0568 488.6836 512.1079 1380 468.2504 483.9429 473.6369 485.3784 488.7794 526.3387 1390 468.1335 483.9416 472.3706 484.3628 488.2863 540.0899 1400 468.0142 482.9813 471.9997 483.3088 487.4904 553.8915 1410 466.8995 482.0902 470.6258 481.7724 486.2476 566.5863 1420 466.5216 481.59 469.5311 481.1345 485.1798 580.9732 1430 466.531 481.1078 469.2358 480.5318 484.6591 593.7897 1440 466.4679 479.6379 468.5451 478.9118 482.9006 605.284 1450 466.0739 479.1341 468.1141 478.4231 481.7314 616.0259 1460 465.5275 477.2334 466.9469 476.9818 479.4764 627.6217 1470 465.475 476.0634 466.4246 476.04 478.3395 638.096 1480 465.3148 474.7437 465.0917 474.821 475.7333 649.0126 -19- 1490 464.893 473.1321 463.6034 473.9495 473.7809 659.7145 1500 465.3832 471.7091 462.428 473.1853 471.9186 668.1813 1510 465.5477 470.8176 460.5404 471.8137 470.0658 675.1821 1520 465.7189 468.7708 458.9512 469.8114 467.7214 680.3581 1530 465.7028 467.6414 457.4316 468.0848 464.567 680.8393 1540 466.9077 466.0231 456.9607 467.497 463.0234 681.0331 1550 467.2871 464.4649 456.143 466.6337 460.8119 680.2307 1560 467.2409 463.1641 454.7622 465.6524 458.9407 677.3785 1570 468.7928 462.5857 455.1233 465.5251 457.6504 674.1614 1580 470.6503 461.6387 455.3569 466.5734 455.4254 670.8505 1590 473.1141 461.2436 455.9105 467.0915 455.0637 667.2418 Frequency Surface Impedance by Fibre type (Pa s m1) _________ (Hz) 22D 80D GD M WD 4D15D 785.7303 884.2208 782.9977 1477.708 687.1237 785.7353 718.4778 804.7495 707.3784 1389.018 642.1156 720.2484 657.2947 732.4657 681.5748 1333.058 654.2222 659.3 603.1733 666.4752 736.6137 1275.908 732.6414 610.7538 561.0269 613.5271 865.6086 1173.787 852.7415 571.522 524.2072 567.1039 972.4744 1116.782 943.4159 536.3333 491.8705 523.2616 1088.406 1062.949 1028.642 507.6563 462.3124 483.7531 1165.109 996.1116 1080.462 483.2742 434.1168 447.1617 1189.514 924.5998 1093.384 460.464 411.4903 416.0766 1193.458 863.1624 1095.398 442.9591 210 390.707 385.3226 1159.423 793.7032 1075.685 426.9565 220 372.5823 357.8447 1120.597 723.3563 1052.693 413.9044 230 357.3968 332.667 1074.123 657.6625 1033.104 403.6202 240 343.4236 308.6134 1033.073 611.1325 1011.123 395.0769 250 330.4452 284.79 989.404 600.7332 987.8503 388.1868 260 320.0221 266.2716 963.1207 639.8239 977.0614 384.0788 270 304.6539 245.8355 931.7692 683.871 957.4951 380.6035 280 286.5084 227.8719 911.2884 727.784 941.3455 378.6406 290 273.1191 211.8934 894.2521 771.7812 924.3347 378.1011 300 266.9112 197.2706 880.9462 814.2416 907.1638 377.5875 310 266.3902 182.2966 866.213 852.0315 886.6703 377.3374 320 268.4054 168.4793 855.025 871.6944 865.8877 374.8309 330 272.7222 155.8054 846.1505 867.103 844.6321 362.9171 340 278.9698 145.579 833.7882 848.9665 822.5124 331.043 350 286.1371 139.0995 825.6141 820.7645 803.3458 310.6285 360 293.6452 135.3913 814.028 788.9873 784.5992 326.8274 370 302.6212 134.2916 803.8721 757.7443 767.4952 363.3794 380 309.3639 133.7144 792.4227 726.9256 748.4117 389.6855 -20 - 390 319.5636 136.4737 783.2151 707.8955 736.0379 411.754 400 331.2942 141.2171 772.5741 689.7197 722.1171 430.1331 410 344.6353 148.6165 764.0341 675.1258 710.3712 446.7385 420 356.5452 156.9468 756.6661 664.2225 700.4526 460.5769 430 369.9538 167.677 748.9196 653.877 690.4234 474.8242 440 384.0868 179.6792 742.2127 644.3222 681.4558 489.3906 450 398.4806 192.6831 735.7097 635.1456 672.8806 503.3135 460 413.7323 206.8203 730.2486 625.9121 665.3347 519.1483 470 430.3161 222.8966 725.587 616.4058 658.262 535.6442 480 446.2321 237.9709 720.1061 607.6378 651.2771 550.8548 490 464.0681 255.5874 716.0159 599.8003 645.1998 566.0151 500 482.0921 273.8 711.3782 594.2649 639.3785 580.3322 510 500.9509 293.1604 706.3986 590.0819 633.4756 595.0002 520 520.5402 313.6901 702.3282 586.8492 628.4478 609.4786 530 539.4349 334.0457 698.4555 583.0387 623.7213 623.9915 540 560.6654 358.1133 692.9418 578.0375 618.2194 639.2614 550 581.205 381.4632 687.8735 572.9871 613.2316 653.6016 560 602.1384 405.9277 684.6538 568.2594 609.3403 666.734 570 622.1426 431.703 680.089 563.6408 604.9822 678.0273 580 643.6879 461.25 675.7361 558.6355 600.9388 689.4199 590 664.7304 491.6036 670.5613 554.7106 596.2114 699.5002 600 684.6138 522.6036 666.2056 551.3164 592.2155 707.3417 610 704.8901 558.09 662.4967 548.6356 588.8729 715.6196 620 723.8235 595.348 658.1709 547.2564 585.2053 721.9479 630 740.8241 634.0476 653.1 546.3928 580.6616 726.2746 640 758.731 679.9207 648.7898 547.5599 577.1425 730.4152 650 771.1506 720.8579 644.5588 549.0359 573.4924 728.7675 660 782.5734 771.9432 638.8894 549.3161 568.7928 727.6597 670 789.6869 821.5167 632.1585 548.312 563.0934 724.2924 680 797.6056 878.4459 627.0167 547.6398 559.2881 724.6121 690 802.8078 940.6756 624.165 547.6482 556.1845 719.9794 700 807.5806 1009.607 621.1143 547.8105 554.1095 715.9187 710 808.1018 1082.606 616.844 546.8283 550.6808 708.5741 720 806.6044 1164.153 613.2116 545.5419 547.9858 700.9366 730 803.0147 1243.2 609.0709 545.083 545.0739 691.2488 740 796.6917 1330.306 605.3167 544.0782 541.8859 680.12 750 788.408 1407.362 602.3557 543.8113 539.7734 670.8337 760 773.973 1476.088 598.0534 542.2344 535.8388 659.7009 770 759.9807 1532.627 595.4176 542.7092 534.0124 649.5947 780 744.6859 1573.01 590.717 542.1188 530.8061 638.7533 790 726.509 1583.209 587.045 540.6823 527.7953 625.9142 800 707.7712 1571.967 582.9663 540.1137 525.0913 612.7657 810 689.3687 1529.643 580.1823 538.2834 522.6981 600.3369 -21 - 820 672.0579 1475.271 576.2166 536.5541 520.251 586.9888 830 647.8146 1385.277 573.9668 533.6143 517.9593 571.0105 840 629.7877 1319.451 570.5071 532.1404 515.6245 557.9086 850 608.5477 1242.718 566.8149 529.6926 513.3865 544.0009 860 590.551 1154.612 564.355 527.1473 511.0938 531.852 870 571.9331 1081.447 561.6194 525.0952 509.3358 520.1708 880 551.1861 1006.123 558.0775 521.6549 507.0742 507.8068 890 533.1578 930.816 555.5688 518.491 505.3883 497.0844 900 517.5769 877.0105 552.8371 516.7771 503.5023 487.3913 910 500.8604 818.2595 549.825 513.9555 501.7051 477.0482 920 484.6736 764.2629 547.3728 511.3457 499.9733 467.0661 930 469.2442 716.5803 544.3047 508.5809 498.2117 458.5774 940 454.4955 665.2208 542.2389 506.2496 496.7419 449.4132 950 441.7604 628.0989 539.734 504.5144 495.3264 442.2142 960 428.7267 587.5582 537.0867 502.5863 493.5789 435.0415 970 416.349 551.7773 534.8463 500.9669 492.3093 428.5287 980 405.9534 520.6362 532.6066 499.9518 491.1974 422.9983 990 396.6161 491.5046 530.962 499.2083 490.278 418.5604 1000 386.2406 460.7121 528.2472 497.321 488.6469 413.1158 1010 377.1116 433.0987 526.1103 495.7306 487.4506 408.7959 1020 368.7011 407.0611 523.5231 494.0844 485.8627 405.7045 1030 362.1378 385.2826 521.2155 493.2924 484.7415 403.0477 1040 354.7558 361.3409 518.3944 491.2745 483.1151 400.5221 1050 350.0193 340.745 516.8057 490.0745 482.2461 399.5934 1060 346.0636 321.6502 515.0886 489.1357 481.5099 398.4909 1070 342.0134 302.1402 512.9824 487.663 480.4057 398.2104 1080 339.8399 283.8675 511.4174 486.6854 479.5814 398.5272 1090 338.4944 270.1178 509.7893 485.6541 479.0308 399.6172 1100 336.6973 255.5185 507.4876 483.8649 478.001 400.6855 1110 334.1735 239.1027 503.81 480.2259 474.901 401.8094 1120 333.0487 226.7833 499.7695 476.8851 471.862 404.4081 1130 333.3033 211.3484 497.1829 474.6883 470.5162 406.6898 1140 337.8702 202.901 497.4459 475.674 471.6161 410.1685 1150 342.3298 194.8688 497.5959 475.7937 472.5677 414.2101 1160 345.6215 187.2682 495.7612 474.6564 471.2452 419.0582 1170 350.0475 180.297 493.6079 472.5231 470.4246 422.9126 1180 355.2928 176.8266 492.7668 471.9755 470.2239 428.3376 1190 361.5295 173.5243 490.3702 469.7724 468.9452 433.842 1200 367.9041 171.9102 489.4604 469.3974 468.9565 438.777 1210 375.2185 173.1228 487.8631 467.4636 467.8773 444.8856 1220 383.2136 175.6353 486.3922 466.5515 467.6828 451.0103 1230 391.1815 178.1739 485.6087 465.2773 467.1963 457.1967 1240 400.4533 184.2678 482.8837 463.4763 465.6709 464.2227 -22 - 1250 409.37 190.4813 482.2902 462.6484 465.7047 470.2042 1260 419.3135 198.4302 480.769 461.3143 464.7613 477.0185 1270 429.6384 207.1719 478.7269 459.8294 463.7064 483.0052 1280 440.5428 217.9935 477.7551 458.5245 463.7696 490.2164 1290 452.3123 229.6322 476.9518 457.3716 463.054 496.8929 1300 462.5463 241.6547 474.731 455.251 461.9481 504.2994 1310 474.2797 255.2026 473.5015 454.2558 461.2472 509.2862 1320 486.7448 270.0607 471.9255 453.1664 460.4435 515.5668 1330 498.949 285.3112 472.0134 453.4483 461.0307 522.2032 1340 511.1193 301.5453 470.9065 452.7182 460.5227 528.2424 1350 523.3698 319.1207 470.1506 451.4835 460.228 533.4755 1360 535.8719 337.7855 468.5022 450.6618 459.9117 538.5627 1370 547.6658 356.7651 468.1471 449.5122 459.8415 543.2867 1380 559.3279 378.0007 467.2437 448.6969 459.3436 548.1401 1390 570.7876 399.4063 466.3863 447.6027 458.7533 552.0204 1400 581.7431 422.2322 465.616 446.9621 458.8359 555.1241 1410 591.8103 446.9957 464.5228 445.6199 458.3131 557.3936 1420 602.2241 473.9505 463.8499 444.7562 457.7916 559.2335 1430 611.7246 501.2884 463.0296 443.8594 457.6776 561.4692 1440 618.9569 531.446 462.2687 442.8933 456.9208 562.7057 1450 626.2819 562.1251 462.0008 442.0031 457.4341 562.8469 1460 632.7302 595.1272 461.4189 441.0616 457.1757 562.2395 1470 638.2412 631.5181 461.4604 439.871 457.2857 561.6761 1480 642.2071 668.1788 460.8995 439.248 456.8626 560.6904 1490 645.8432 706.1454 461.5551 438.208 457.726 558.5233 1500 648.9736 750.2387 461.7311 437.9542 459.3107 557.1258 1510 649.3231 794.9308 462.111 437.5743 459.1864 554.8173 1520 647.8451 843.2214 462.1394 436.6944 458.9136 551.8905 1530 643.6738 886.8923 461.6841 436.3527 458.6251 548.603 1540 638.021 934.9954 461.1996 436.0929 457.9825 544.1815 1550 632.4343 982.383 461.0918 436.2412 457.4798 540.4421 1560 625.5469 1025.939 459.8617 435.7872 457.1047 536.969 1570 618.9696 1070.568 460.072 436.0304 457.1086 532.6362 1580 611.7659 1109.218 461.2905 436.1039 458.3275 528.9834 1590 605.2048 1145.279 462.1239 436.9734 459.0705 525.0945

Claims

-23 -Claims 1. A material comprising: a first proportion of fibres, each fibre in the first proportion of fibres having substantially the same linear mass density as the other fibres in the first proportion of fibres, the linear mass density of the first fibres being in the range of 0.1 to 25 dtex; and a second proportion of fibres, each fibre in the second proportion of fibres having substantially the same linear mass density as the other fibres in the second proportion of fibres, the linear mass density of the second fibres preferably being at least 2 dtex greater than the linear mass density of the first fibres and being in the range of 5 to 30 dtex; wherein the material is configured to attenuate sound waves in the vicinity of the material.
2. The material as claimed in claim 1, wherein at least one of: the material pore structure; the material surface geometry; and the material acoustic admittance is configured to maximise the attenuation of sound waves, preferably sound waves emitted from a nearby source.
3. The material as claimed in claim 1 or 2, wherein the linear mass density of the second fibres is at least 2.5 dtex greater than the linear mass density of the first fibres, preferably at least 5 dtex greater than the linear mass density of the first fibres, preferably at least 7.5 dtex greater than the linear mass density of the first fibres, preferably at least 10 dtex greater than the linear mass density of the first fibres.
4. The material as claimed in claim 1, 2 or 3, wherein the linear mass density of the first fibres is in the range of I to 10 dtex, preferably in the range of 2 to 8 dtex, preferably in the range of 3 to 7 dtex, preferably in the range of 4 to 5 dtex.
5. The material as claimed in any one of the preceding claims, wherein the linear mass density of the second fibres is in the range of 5 to 25 dtex, preferably in the -24 -range of 10 to 20 dtex, preferably in the range of 12 to 18 dtex, preferably in the range of 14 to 16 dtex.
6. The material as claimed in any one of the preceding claims, wherein the material is configured to attenuate sound waves in the vicinity of the material so as to reduce the sound pressure level of the propagated sound wave by at least 1 dB compared with the sound pressure level of the incident sound wave.
7. The material as claimed in claim 1, wherein the material is configured to attenuate sound waves in the vicinity of the material so as to reduce the sound pressure level of the propagated sound wave by at least 2 dB compared with the sound pressure level of the incident sound wave, preferably by at least 4 dB compared with the sound pressure level of the incident sound wave, preferably by at least 6 dB compared with the sound pressure level of the incident sound wave, preferably by at least 8 dB compared with the sound pressure level of the incident sound wave.
8. The material as claimed in any one of the preceding claims, wherein the first fibres comprise synthetic fibres, preferably polyester fibres or polyethylene fibres or polyurethane fibres or the.
9. The material as claimed in any one of the preceding claims 1, wherein the first fibres comprise natural fibres, preferably cotton fibres or wool fibres or the like.
10. The material as claimed in any one of the preceding claims, wherein the second fibres comprise synthetic fibres, preferably polyester fibres or polyethylene fibres or polyurethane fibres or the like.
11. The material as claimed in any one of the preceding claims, wherein the second fibres comprise natural fibres, preferably cotton fibres or wool fibres or the like.
12. The material as claimed in any one of claims I to 8, 10 or 11, wherein the first fibres comprise bicomponent fibres.

-25 -
13. The material as claimed in any one of the preceding claims, wherein the first fibres comprise hollow fibres.
14. The material as claimed in any one of claims I to 10, 12 or 13, wherein the second fibres comprise bicomponent fibres.
15. The material as claimed in any one of the preceding claims, wherein the second fibres comprise hollow fibres.
16. The material as claimed in any one of the preceding claims, wherein the first proportion of fibres combined with the second proportion of fibres comprises substantially 100% of the material.
17. The material as claimed in any one of claims ito 15, wherein the first proportion of fibres combined with the second proportion of fibres comprises less than 100% of the material, with the remainder of the material comprising at least one of synthetic fibres, natural fibres, feathers and down.
18.The material as claimed in claim 17, wherein the remainder of the material comprises at least one of goose down, duck down, goose feathers and duck feathers.
19. The material as claimed in any one of the preceding claims, wherein the material is configured to attenuate sound waves having a frequency in the range of 100 to 1600 Hz, preferably in the range of 300 to 1200 Hz, preferably in the range of 500 to 1000 Hz.
20. The material of any one of the preceding claims, wherein the first fibres are formed into a nonwoven fabric.
21. The material as claimed in any one of the preceding claims, wherein the second fibres are formed into a nonwoven fabric.

-26 -
22. The material as claimed in claim 20 or 21, wherein the nonwoven fabric is formed by carding.
23. The material as claimed in claim 20 or 21, wherein the nonwoven fabric is a vertically lapped nonwovon.
24. The material as claimed in any one of claims 1 to 19, wherein the first fibres are formed into a plurality of ball fibres with or without voids.
25. The material as claimed in any one of claims I to 20, wherein the second fibres are formed into a plurality of ball fibres with or without voids.
26. The material as claimed in any one of claims 1 to 19, wherein the first fibres are formed into a plurality of ball fibres, the second fibres are formed into a plurality of ball fibres and the material comprises at least one of a random, an ordered and a regular mixture of the first ball fibres, the second ball fibres and voids.
27. The material as claimed in claim 26, wherein the first fibres comprise from about 5 to 95% of the material, preferably about 20 to 80% of the material, preferably about 35 to 65% of the material, preferably about 50 % of the material, and the second fibres comprise from preferably about 5 to 95% of the material, preferably about 20 to 80% of the material, preferably about 35 to 65% of the material, preferably about 50% of the material.
28. The material as claimed in any one of claims I to 23, wherein the first fibres are formed into a first web or batt and the second fibres are formed into a second web or batt.
29. The material as claimed in claim 28, wherein the first web or batt is separately provided from the second web or batt and a layered structure is formed by overlaying one of the first and second web or batt on the other of the first and second web or batt.

-27 -
30. The material as claimed in claim 29, wherein the first web or batt is overlaid onto the second web or batt and the layered structure is rolled about an axis that is substantially parallel with a first axis of the plane of the layered structure to form a generally cylindrical rolled structure, wherein the first fibres form the inner surface of the rolled structure and the second fibres form the outer surface of the rolled structure.
31.The material as claimed in claim 30, wherein the rolled structure has a cross-section that is generally circular, elliptical or rectangular.
32. The material as claimed in claim 30 or 31, further comprising at least one further proportion of fibres formed into a third web or batt, the third web or batt being overlaid onto the layered structure such that when the layered structure is rolled about the axis, the third web or batt forms either the inner surface or the outer surface of the rolled structure.
33. The material as claimed in any one of claims 30 to 32, further comprising a block of fibres, a foam material or a void, the block, the foam material or the void being laid onto or created in the centre of the layered structure such that when the layered structure is rolled about the axis, the block, the foam material or the void forms a central portion of the rolled structure.
34. The material as claimed in any one of claims I to 23, wherein the material is formed as a composite structure with the first fibres forming a central core of a composite structure and the second fibres forming an outer core of a composite structure.
35. A filled product comprising: a casing, the casing preferably comprising a woven fabric; and the material as claimed in any one of the preceding claims, wherein the material is sealed inside the casing so as to form the filled product.

-28 -
36. The filled product of claim 35, wherein the product comprises at least one of the following: a pillow, a duvet, a mattress, a mattress topper, a lined curtain, a valance, a pelmet, a headboard padding or cover, a wall hanging, carpet underlay, insulation, or the like.
37. The filled product of claim 35 or 36, wherein the casing comprises an open woven fabric, preferably comprising woven fibres selected from cotton, nylon, wool, rayon, polyester, etc.
38.A material comprising: a first proportion of fibres, each fibre in the first proportion of fibres having substantially the same linear mass density as the other fibres in the first proportion of fibres, the linear mass density of the first fibres being in the range of 4 to 5 dtex; and a second proportion of fibres, each fibre in the second proportion of fibres having substantially the same linear mass density as the other fibres in the second proportion of fibres, the linear mass density of the second fibres being in the range of 12 to 18 dtex; wherein the material is configured to attenuate sound waves in the vicinity of the material so as to reduce the sound pressure level of the propagated sound wave by at least 5 dB compared with the sound pressure level of the incident sound wave.