CN116456853A

CN116456853A - Artificial down filling material

Info

Publication number: CN116456853A
Application number: CN202180070540.5A
Authority: CN
Inventors: 安德斯·贝格纳; 穆凯什·夏尔马; 杰弗里·斯克特·哈格德; 安杰尔·安东尼奥·德拉霍兹
Original assignee: Ikea Supply AG
Current assignee: Ikea Supply AG
Priority date: 2020-10-16
Filing date: 2021-10-14
Publication date: 2023-07-18

Abstract

An artificial down fill material comprising artificial down clusters (1), wherein each of the down clusters (1) comprises a plurality of filaments (10) arranged side by side in bundles, the filaments (10) being bonded together at bonding locations 20, preferably melt bonded together at bonding locations 20, wherein the filaments (10) are self-crimping multicomponent filaments (10) having a cross section with at least three corners (211).

Description

Artificial down filling material

Technical Field

The present invention relates to artificial down filling materials to be used in e.g. pillows, sofa cushions and quilts to replace or at least supplement natural down. Furthermore, the invention relates to a method for producing such an artificial down filling material.

Background

Feathers and down from birds have long been used as filling materials in pillows, quilts and other products such as cushion members. In addition, feathers and down from birds (e.g., ducks and geese) have been used as insulation in clothing such as jackets. The down has very good heat preservation property and is a light material. In addition, it is bulky. Therefore, it is used for clothing and quilts. In addition, the memory effect of down combines with the elastic properties of longer feathers to provide a comfortable filling material for pillows.

In view of its source, various attempts have been made in the art to find alternatives to feathers and down from birds. Some of these alternatives are attracted to feathered or down-like materials and thus focus on structural similarity, while the remainder focus on function first. Indeed, many materials have been provided as alternatives to down for insulation in garments. However, such materials, while having good insulating properties, find less use as filling materials for pillows and quilts, particularly for pillows.

For use in pillows, it would be desirable to provide an artificial light down fill material having a high bulk density (bulk), i.e., low density, as well as being fluffy and elastic. Furthermore, an artificial down fill material for providing a memory effect, i.e. a moderate recovery rate after depressurization, would be desirable.

Some examples of artificial feathers and down are known in the art. In US3892909a, a combination of artificial objects is disclosed, each of which simulates the functioning of poultry down as found in nature. The artificial object comprises a large number of fibres formed in a circular configuration, which can be repeatedly deformed in a spring-like manner by applying a load and which return substantially to their original form upon releasing the load. Furthermore, in US5,851,665, a filler material comprising bonded thermoplastic fiber clusters is disclosed. The fibers have a crimped configuration and are bonded together at only one location in each tuft. The fibers are combined in the filler material at locations that vary in different clusters. Furthermore, in EP 0 067 498, a filler material is disclosed which comprises a large number of mechanically crimped fibres which are bonded together at one end in such a way that their crimp phases deviate from each other and which cause the fibres to spread radially around the end. Crimping and bonding at the very ends of the fibers means in particular that the material is difficult to produce in an efficient manner.

However, there remains a need in the art for an artificial light down fill material with high bulk to be used as a fill material in, for example, pillows, sofa cushions or quilts. Preferably, the artificial lightweight down fill material should have the same or similar characteristics as natural down but at a lower cost than natural down. Also, the artificial lightweight down fill material should preferably have advantages associated with synthetic fill materials.

Disclosure of Invention

Thus, according to a first aspect, an artificial down fill material is provided. The artificial down fill material comprises artificial down clusters. Each of the down clusters comprises a plurality of filaments arranged side-by-side in a bundle. The filaments are typically filaments of thermoplastic polymers. To provide a tuft, the filaments are bonded together at a bonding location. The filaments are preferably melt-bonded together, i.e. the filaments are heated to at least partially melt a portion of them, whereby they are bonded together. In addition, to provide the desired bulk and other down-like characteristics, the filaments are self-crimping multicomponent filaments, such as bicomponent filaments.

However, self-crimping has been found to be insufficient on its own to provide the desired properties. It has been found that providing such a synthetic down cluster for a multicomponent filament that is self-crimping and has a cross-section with at least three corners: it has a high bulk (i.e. low density) and also provides the artificial down filling material with a natural down-like elasticity. In addition, the artificial down fill material comprising such artificial down clusters has a suitable memory effect, i.e. a moderate recovery rate after decompression.

The properties of the artificial down cluster can be further improved if the filaments are not only self-crimping, but if the bundles of filaments are deformed as well. As recognized in the art, "textured" is a generic term for yarns comprising filaments that have been imparted with an apparent bulk or bulk that is significantly greater than conventional yarns of similar filament count, or made more extensible by filament texturing. The deformation is typically provided by physical treatment, chemical treatment, thermal treatment, or any combination of these. According to one embodiment, the bundles of filaments are deformed by a gas jet method. In the gas jet method, the yarn may be directed through the turbulent region of the gas jet at a faster rate than it is drawn distally of the jet. Thus, in the jet, the yarn structure is opened, forming a loop, and the structure is closed again. Thus, some loops are locked inside the yarn, while other loops are locked on their surface, thus increasing the bulk of the yarn. As the skilled person realizes, texturing involves random filament texturing. Instead, crimping involves repeated, symmetrical filament deformation, which can be defined and described by parameters such as crimp number, crimp rate, crimp angle, etc.

Self-crimping is provided by drawing the multi-component filaments and requires the components of the multi-filament itself to have different yield behaviors. In contrast, the deformation is not caused by the filaments themselves, but by external factors, such as physical treatment, chemical treatment, thermal treatment or any combination of these.

Without being bound by any hypothesis, it is believed that self-crimping, which causes "helical" segments, provides unique characteristics to the artificial down cluster of the invention. Furthermore, optional texturing of the bundles of filaments ("random" crimping and/or placement) may provide additional improvements to bundles of filaments provided by self-crimping.

To provide a self-crimping multicomponent filament, the components are typically arranged side-by-side in the filament. It is less preferred that it is arranged in a sheath-core like manner, however this requires that it is arranged eccentrically, since it cannot cause self-crimping if they are arranged symmetrically around the centre of the filament. According to one embodiment, the components are arranged eccentrically, for example side by side. The multicomponent filaments are typically bicomponent filaments in which at least one of the two components is arranged eccentrically. Preferably, the two components are arranged eccentrically. Thus, the components are asymmetrically distributed across the cross-section of the multicomponent filaments.

The filaments are typically bicomponent filaments, although the filaments may comprise more than two components. According to one embodiment, the filaments are bicomponent filaments having components arranged side by side.

To provide an artificial down fill material with the desired elasticity, yet still provide a fluffy, lightweight material, the cross section of the multicomponent filaments has been found to be important. To provide the desired properties, the cross-section of at least some multicomponent filaments preferably has at least three corners. Thus, at least 50% by weight of the total amount of multicomponent filaments in the down cluster has a cross-section with at least three corners. Preferably, at least 75% by weight, such as at least 90% by weight or at least 95% by weight, of the total amount of multicomponent filaments in the down cluster has a cross-section with at least three corners. According to one embodiment, the cross-section of the multicomponent filaments in the down cluster has at least three corners.

Multicomponent filaments having a cross-section with at least three corners provide artificial down clusters having high bulk, yet desirable elasticity. It appears that filaments having a cross section with at least three corners, like filaments having a circular cross section, provide at least similar bending resistance and flexibility in all directions, as opposed to filaments having a flat cross section, for example. However, the presence of ridges extending along the longitudinal extension of the filaments provides a greater bulk with reduced weight, thus providing artificial down clusters having characteristics similar to those of natural down. Whereas filaments are produced by melt extrusion, the corners are most often not sharp, but rounded. Thus, the cross section of the filament can also be considered to have at least three rounded tips. Further, according to at least some embodiments, the cross-section of the filament may be considered to have at least three lobes, such as a tri (3) -lobe, a tetra (4) -lobe, or a penta (5) -lobe, such as a tri (3) -lobe.

As the skilled person realizes, the cross section of a filament extruded through a trilobal die will typically have three rounded corners. Furthermore, the sides of such a section are typically more or less concave. The cross section of the filaments extruded through the trilobal die is preferably symmetrical, wherein the angle between the lobes is substantially the same, i.e. about 120 degrees. Such a cross section is different from the cross section of a filament extruded through a T-die (resulting in angles of 90 degrees, 90 degrees and 180 degrees, respectively).

According to one embodiment, the cross section of the filament has 3, 4 or 5 corners. Preferably, the cross-section is symmetrical, wherein the angles between the corners are the same, i.e. about 120 degrees for a cross-section with 3 corners, about 90 degrees for a cross-section with 4 corners, and about 72 degrees for a cross-section with 5 corners. In filaments having a cross section with 3, 4 or 5 corners, the sides of the cross section connecting the corners are preferably concave, i.e. they curve inwardly towards the centre of the cross section. The cross-section with 3 corners and concave sides is opposite to a lux triangle (Reuleaux triangle) with 3 corners but convex sides. Extrusion through a triangular die typically provides a cross-section with a convex edge. Furthermore, the cross-section with 3 corners and concave sides also differs from a T-shaped cross-section, which typically has at least one convex edge. The cross section of the filaments preferably has 3 or 4 corners, for example 3 corners. According to one embodiment, the filaments are trilobal in cross-section. It has three corners and the sides of the cross section connecting the corners are concave. Preferably, the cross-section is symmetrical, wherein the angle between the corners is substantially the same, i.e. about 120 degrees.

According to one embodiment, the multicomponent filaments are bicomponent filaments having a cross-section with 3 corners and sides connecting the corners are concave. Preferably, the cross-section is symmetrical, wherein the angle between the corners is substantially the same, i.e. about 120 degrees. The filaments are preferably solid. While hollow filaments can provide artificial down clusters with reduced weight, it has been found that hollow filaments do not provide the desired bulk.

Filaments having a cross-section with at least three corners provide a significantly greater bulk to the artificial down cluster without adding weight than artificial down clusters having filaments with a circular or flat cross-section. Furthermore, the ridges created by the cross section with at least three corners and extending in the longitudinal extension of the filaments provide artificial down clusters having elastic properties similar to those of natural down.

The artificial down fill material of the invention is washable and provides no entanglement or a very low degree of entanglement after washing. In addition, the original shape is generally maintained after washing.

To provide the artificial down cluster, a plurality of filaments are arranged side by side in bundles and bonded together. The bundle and thus the tuft may comprise 50 to 1000 filaments, for example 100 to 1000 filaments, 250 to 750 filaments, or 250 to 500 filaments. Filaments in an elongated, straight state are typically 20mm to 120mm long, for example 30mm to 90mm, or 35mm to 80mm long. Further, the filaments in an elongated, straight state may be at least 55mm long, such as 55mm to 75mm long. For shorter filaments, the recovery rate after depressurization is quite fast, which means that the sought memory effect may be diminished. If the filaments become too long, the bundles become more entangled, meaning that the artificial down fill material may not be perceived as a homogeneous material. In addition, it is more prone to entanglement after washing.

In addition, the filaments are typically thin filaments. Thus, the linear density of the filaments may be from 0.5 dtex to 10 dtex, for example from 2 dtex to 5 dtex. As known to the skilled artisan, 1 dtex is equal to 0.9 denier. Furthermore, each down cluster may comprise more than one type of filament. As already described, at least 50% by weight of the cross-section of the total amount of the multicomponent filaments in the down cluster can have at least three corners. The down clusters may also comprise a small portion of filaments having, for example, a circular cross-section.

In addition, the down clusters may include filaments having different linear densities. This may improve yarn opening and/or texturing.

Typically, at least 50% by weight of the total amount of filaments in the down cluster are self-crimping multicomponent filaments. Multicomponent self-crimping filaments provide good bulk properties. According to one embodiment, at least 75 wt%, such as at least 90 wt% or at least 95 wt%, of the total amount of filaments in the down cluster are self-crimping multicomponent filaments.

Typically, the first component of the multicomponent filaments comprises a first thermoplastic polymer and the second component of the multicomponent filaments comprises a second thermoplastic polymer. To provide a multicomponent filament having self-crimping characteristics, the first thermoplastic polymer and the second thermoplastic polymer have different yield behaviors, e.g., different stress relaxation responses, different melt flow rates, different elastic ratios, and/or different intrinsic viscosities, whereby the multicomponent filament is self-crimping, i.e., it will crimp if it is stretched. Self-crimping multicomponent filaments are known in the art (see, e.g., US 6,158,204). Furthermore, at least one of the thermoplastic polymers is spinnable.

As already described, at least one of the components of the multicomponent filaments is distributed eccentrically over the cross section of the multicomponent filaments. Thus, the first thermoplastic polymer and/or the second thermoplastic polymer is distributed eccentrically over the cross-section of the multicomponent filaments. According to one embodiment, the first thermoplastic polymer and the second thermoplastic polymer are distributed side by side in the filament.

For self-crimping, it is desirable to have the first thermoplastic polymer and the second thermoplastic polymer have different yield behaviors, for example, at least one of the following: different stress relaxation responses, different melt flow rates, different elastic ratios, and different intrinsic viscosities. Thus, according to one embodiment, the first thermoplastic polymer and the second thermoplastic polymer have different intrinsic viscosities. The difference in intrinsic viscosity between the first thermoplastic polymer and the second thermoplastic polymer may be at least 0.01dl/g (deciliters/gram), for example at least 0.03dl/g or at least 0.05dl/g. Intrinsic viscosity may be determined according to ISO 1628:2009, where part 1 defines the general principle and parts 2 to 6 define the principle of a specific polymer. According to one embodiment, the first thermoplastic polymer and the second thermoplastic polymer have different Melt Flow Rates (MFR). The Melt Flow Rates (MFR) of the first thermoplastic polymer and the second thermoplastic polymer, as determined according to ASTM D1238-13, may differ by at least 1%, such as at least 2%, at least 5%, or at least 10%.

The relative proportions of the two thermoplastic polymers in the filaments can vary. In multicomponent, e.g., bicomponent filaments, the first thermoplastic polymer can be present in an amount of 20 wt.% to 80 wt.%, e.g., 25 wt.% to 75 wt.%. Accordingly, the second thermoplastic polymer may be present in an amount of 80 wt% to 20 wt%, for example 75 wt% to 25 wt%. According to one embodiment, one of the thermoplastic polymers is present in a higher amount than the other. Preferably, the lower cost thermoplastic polymer is present in an amount of 50 to 80 wt%, for example 50 to 75 wt%. As already mentioned, the first thermoplastic polymer and the second thermoplastic polymer may be distributed side by side in the filament.

At least one of the thermoplastic polymers in the filaments is a spinnable polymer. The at least two thermoplastic polymers may be the same kind of polymer as long as their yield behavior, e.g. their intrinsic viscosity, is different, or they may be different kinds of polymers (e.g. PET and PBT).

According to one embodiment, the first thermoplastic polymer is selected from polyethylene terephthalate (PET), modified PET (e.g., PET modified with up to 20 mole percent isophthalic acid or by incorporating polyolefin (e.g., PE or PP) segments), polybutylene terephthalate (PBT), poly (trimethylene terephthalate) (PTT), polyethylene furandicarboxylate (PEF), copolyesters, polyamides (e.g., nylon 6 (PA 6), nylon 6/6 (PA 6, 6), and nylon 6/12 (PA 6, 12)), modified polyamides (e.g., polyamide modified with cationic dyeable groups or uv stabilizers or by incorporating polyolefin (e.g., PE or PP) segments), copolyamides, polyethylene (PE), polypropylene (PP) (e.g., isotactic polypropylene and syndiotactic polypropylene), and other spinnable polymers. Furthermore, the first thermoplastic polymer may be a bio-based and/or biodegradable polymer, such as polylactic acid (PLA), polybutylene succinate (PBS), polyethylene furandicarboxylate (PEF) or Polyhydroxyalkanoate (PHA), such as Polyhydroxybutyrate (PHB). Polylactic acid (PLA) represents a preferred bio-based and biodegradable polymer.

Similarly, according to one embodiment, the second thermoplastic polymer is selected from polyethylene terephthalate (PET), modified PET (e.g., PET modified with up to 20 mole percent isophthalic acid or PET modified by incorporation of polyolefin (e.g., PE or PP) segments), polybutylene terephthalate (PBT), poly (trimethylene terephthalate) (PTT), polyethylene furandicarboxylate (PEF), copolyesters, polyamides (e.g., nylon 6 (PA 6), nylon 6/6 (PA 6, 6), and nylon 6/12 (PA 6, 12)), modified polyamides (e.g., polyamide modified with cationic dyeable groups or uv stabilizers, or polyamide modified by incorporation of polyolefin (e.g., PE or PP) segments, copolyamide, polyethylene (PE), polypropylene (PP) (e.g., isotactic polypropylene and syndiotactic polypropylene), and other spinnable polymers. Further, the second thermoplastic polymer may be a bio-based and/or biodegradable polymer, such as bio-based PET, polylactic acid (PLA), polybutylene succinate (PBS), or Polyhydroxyalkanoate (PHA), such as Polyhydroxybutyrate (PHB). Polylactic acid (PLA) represents a preferred bio-based and biodegradable polymer.

According to one embodiment, the first thermoplastic polymer is PET or modified PET and the second polymer is PBT or modified PBT. In such embodiments, the PBT generally comprises at least 20 wt% of the filaments. The proportion of at least 20 wt.% of PBT preferably provides fluffy and elastic down clusters similar to natural down. Furthermore, the weight ratio of PET to PBT may be 1:1 or more than 1:1. Thus, the weight ratio of PET to PBT can be in the range of 1:1 to 4:1. PET and PBT may be arranged side-by-side in the filaments.

In embodiments in which the first thermoplastic polymer and/or the second thermoplastic polymer is PET, the PET may be recycled PET. Similarly, in embodiments in which the first thermoplastic polymer and/or the second thermoplastic polymer is PBT, the PBT can be recycled PBT. In addition, PBT can be upgraded reconstituted PET.

As already described, the artificial down filling material comprises artificial down clusters. Each of the down clusters comprises a plurality of filaments arranged side-by-side in a bundle. To provide a tuft, the filaments are bonded together at a bonding location. The beam may be circular in cross-section at the junction. Furthermore, the cross section at the bonding location may be flat.

According to one embodiment, the filaments are preferably melt-bonded together, i.e. the filaments are heated to at least partially melt a portion of them, whereby they are bonded together. Pressure is typically applied at the bonding location as the filaments are melt bonded together. Heat and pressure may be applied through the heated surface. Thus, a calender having at least one heated roll may be used. One roll in the calender may be provided with alternating insulation pads and bonding tips along its periphery to repeatedly provide a bonding portion along the longitudinal extension of the filament-containing yarn fed to the calender. Alternatively, the heat may be applied by, for example, laser, ultrasonic energy, and/or high frequency. Downstream of the calender, the yarns may be cut into down clusters by cutting the filaments between bonding locations. The yarn may be cut into down clusters in a staple cutter.

The length of the bonding locations is preferably as short as possible. There remains a need to combine filaments into clusters to provide desired properties that result not only from the filaments themselves, but also from arranging the filaments into discrete bundles. According to one embodiment, the bonding locations extend along less than 20%, such as less than 10%, or less than 5% of the length of the filaments in the elongated, straight state. The bonding location is between the ends of the filaments, but preferably not at any of the ends. Thus, the filaments are preferably not bonded together at their ends, leaving free filament ends at each end of the tuft. According to one embodiment, the tuft has free filament ends at each end of the tuft. In such tufts, the free ends of the filaments at each end of the tuft are interspersed into a plume. Thus, the tuft may comprise a first plume and a second plume exiting the free filament ends. If the bonding location is centrally located, the overall shape of the two plumes will be similar, while if the bonding location is closer to one of the ends of the filament, the shape will be different. Not only is the artificial down cluster of the invention easier to produce, because it can be produced from continuous yarns that are cut into artificial down clusters after the filaments are joined together, but the filaments in the artificial down cluster of the invention are also more difficult to separate and thus are more resistant to washing, for example.

Furthermore, not only the bonding itself, but also the location of the bonding site influences the properties of the artificial down filling material. According to one embodiment, the artificial down filling material comprises a first type of clusters and a second type of clusters, the two types of clusters differing in the location of the binding sites. The bonding locations in the first type of tuft may be substantially centered while the bonding locations in the second type of tuft are substantially closer to one end of the filament.

According to one embodiment, the center of the bonding locations in the first type of tuft is located at a distance from each end of the filament corresponding to at least 40% of the total length of the filament in an elongated, straight state. The center of the bonding locations in the tufts of the second type are located a distance from one end of the filaments that corresponds to less than 30% of the total length of the filaments in the elongated, straight state. While the bonding locations in the second type of tuft are closer to one end of the filaments, it is preferable if the bonding locations are not at the ends of the filaments.

In embodiments whereby the artificial down fill material comprises a first type of cluster and a second type of cluster that differ in the location of the binding sites, the weight ratio between the first type of cluster and the second type of cluster may be in the range of 3:1 to 1:3, such as 2:1 to 1:2. Preferably, the artificial down fill material comprises a higher proportion of clusters of the first type than of clusters of the second type, for example 55 to 70 wt% of clusters of the first type and 30 to 45 wt% of clusters of the second type.

In filling materials for e.g. pillows comprising natural down, some natural feathers are typically present to increase the elastic properties. Similarly, the artificial down fill material of the invention may comprise feathers in addition to the artificial down clusters. The feathers may be natural feathers. However, in order not to have to use natural feathers or down at all, the artificial down filling material may preferably comprise artificial feathers.

The artificial down fill material may comprise 60 to 95 wt% artificial down clusters. Furthermore, it may comprise 5 to 30 wt% feathers, such as artificial feathers. While feathers are important for elasticity, down provides various desirable characteristics such as comfort, thermal insulation, and memory effects.

According to one embodiment, the artificial down filling material comprises artificial feathers, wherein each artificial feather comprises at least a first sheet of a first nonwoven material and filaments arranged along one extension of said sheet. The filaments are bonded to the first sheet. Such artificial feathers are known from PCT/SE 2020/050873. The artificial feather comprises a first sheet of a first nonwoven material. The filaments are disposed along one extension of the sheet. Typically, the sheet is a strip. The strip may be a substantially rectangular strip. Although the rectangular strip may be square, it is generally longer than it is wide. For a strip, the filaments may be arranged centrally along the extension of the strip, e.g. the longitudinal extension. The filaments may be monofilaments providing a feel and function very similar to the corresponding portion of natural feathers. In addition, the filaments are bonded to the first sheet. For improved elastic properties, the filaments may be curved. The combination of the stiffer central filaments and the sheet of nonwoven material provides artificial feathers with elastic properties similar to those of natural feathers. By supplementing the elastic properties of the filaments with a nonwoven material, i.e. a bonding material, which also has some elastic properties, the elastic properties are improved. The nonwoven material typically has less than 100g/m ² Is a surface weight of (a) a (c). Furthermore, the nonwoven material is thin. The thickness thereof may be 1mm or less.

The size of the artificial feathers can vary. The feathers may be 10mm to 100mm, for example 20mm to 80mm, for example at least 40mm, for example less than 80mm, or even less than 70mm, or even 40mm to 60mm long. Too short feathers provide less elasticity. Conversely, too long feathers provide too much elasticity and may be perceived as stiff. Further, the width of the artificial feather may be 5mm to 50mm, for example 10mm to 40mm, or 15mm to 25mm. Feathers that are too wide will have their higher weight. Furthermore, too wide feathers do not interact well with other feathers and/or down and may even lose the synergy sought. As already described, the artificial feather may be rectangular. Rectangular artificial feathers are more comfortable in their elastic properties and combine better with down than square (rectangular) artificial feathers. The artificial feather having a rectangular shape may have a longer extension in the direction along the filaments than in the direction perpendicular to the filaments. However, to more closely resemble a feather, one or both ends of the artificial feather may be triangular if desired. By trimming the ends of the rectangular strips, triangular ends can be provided.

The filaments, which may be arranged centrally, may have an arcuate shape, i.e. the filaments are curved. By providing curved filaments, the elastic properties of the artificial feather are further improved. The arc may be a circular arc. The radius of such an arc may be 25mm to 400mm, for example 50mm to 200mm. From the viewpoint of manufacturing artificial feathers, it may be preferable if the arc is an arc of a circle. The method for manufacturing artificial feathers typically includes a calender that may be operated to bend the filaments.

Furthermore, the artificial feathers may also be curved along an extension that is not parallel but, for example, perpendicular to the filaments that may be arranged centrally. The elastic properties can be further improved by bending the artificial feather along the other extension. In addition, artificial feathers that bend along one or more extensions will be less dense and provide less compact filling, thereby providing higher loft (filling power). The cross section of the sheet perpendicular to the extension of the filaments, which may be arranged centrally, may be curved at least one side of the filaments, but typically at both sides. The curvature of the curved section of the sheet may have a circular arc shape. Such arcs may have a radius of 25mm to 250mm, for example 40mm to 150mm.

Although the artificial feather may comprise only one nonwoven sheet, e.g. a strip, it is preferred to provide the artificial feather as a sandwich structure, wherein filaments are arranged between the first nonwoven sheet and the second nonwoven sheet. Such a sandwich structure will further improve the elastic properties. Furthermore, the perception of filaments will be less pronounced when embedded between two nonwoven materials. Furthermore, the risk of the filaments separating from the first nonwoven sheet is reduced. Thus, the artificial feather may comprise a second sheet of a second nonwoven material, such as a strip. The filaments may be disposed between the first and second sheets of nonwoven material. The filaments are also bonded, e.g., melt bonded, to the second sheet.

Further, the first sheet may be bonded, e.g., fusion bonded, to the second sheet. By bonding the first and second sheets of nonwoven material to each other, the elastic properties are further improved. In addition, the structural integrity of the artificial feather is also improved. In addition, the mechanical strength of the bond between the monofilament and the nonwoven is improved. The bonding of the first and second sheets of nonwoven material may be at discrete locations, at a portion of the total area of the sheets, or over the entire area of the sheets.

The first panel may be bonded to the second panel. The bond may take the form of a plurality of bond lines. The bond line may be a straight line. Furthermore, the multiple bond lines are generally not parallel to the extension of the filaments. Furthermore, the bond line is also generally not perpendicular to the extension of the filaments. The bond lines may be arranged like a plume in natural feathers, thereby forming a feathered fish bone pattern together with filaments, which are preferably arranged centrally.

As already described, the nonwoven material sheets in the artificial feather provide the artificial feather with elastic properties. Nonwoven materials are known to the skilled person. The nonwoven material is a textile-like material comprising fibers bonded together. As recognized by the skilled artisan, a nonwoven is a sheet of any natural or original fibers, continuous filaments, or chopped strands that have been formed into a web by any means and bonded together by any means other than braiding or knitting. Additional information about the nonwoven can be found in ISO standard 9092:2019. In the artificial feather of the present invention, a thin nonwoven material is generally used. The nonwoven material may be according to ISO standard 9092:2019. According to one embodiment, the surface weight of the first nonwoven material and/or the second nonwoven material is 1g/m ² To 50g/m ² For example 5g/m ² To 30g/m ² . If the artificial feather is provided as a sandwich structure, the first nonwoven material and the second nonwoven material may be the same kind of material. However, the second sheet may also be another nonwoven material than the first sheet. This may provide artificial feathers with additional elastic properties.

The first nonwoven and/or the second nonwoven of the artificial feather may be spunbond nonwoven, i.e. a spunlaid thermal bond nonwoven. The nonwoven material may also be bonded by hydroentanglement. Although less preferred due to the slightly greater thickness, the nonwoven material may also be bonded by needling. In addition, the nonwoven material may also be bonded by chemical bonding agents (i.e., as a "resin" added as a powder for thermal activation or by spraying or dissolved resin applied in soft silk (fouuard)). In addition, combinations of bonding methods such as hydroentanglement and thermal bonding or resin bonding may also be used.

Because the nonwoven material employed is typically thin (the thickness of the fibers defines the minimum thickness of the nonwoven material), the fibers in the first nonwoven material and/or the second nonwoven material are typically fine fibers. The fibers are typically polymeric fibers. Various polymers may be used in the fibers used in the nonwoven material. The polymer may be a polyester, a polyamide, or an olefin. Specific examples of the polymer include PET (polyethylene terephthalate), PBT (polybutylene terephthalate), PTT (polytrimethylene terephthalate), PEF (polyethylene furandicarboxylate), PLA (polylactic acid), PA6, PA11, PA12, PA4,6, PA4, 10, PA 5,10, PA6, PA6, 10, PA6, 12, PA12, PP (polypropylene), PE (polyethylene), and copolymers thereof.

The first nonwoven and/or the second nonwoven may comprise fibers having a linear density of 0.5 dtex to 10 dtex, for example 1 dtex to 5 dtex. First nonwoven and/or second nonwoven, e.g. spunbondThe nonwoven material or meltblown nonwoven material may comprise fibers having an average diameter of 0.1 μm to 30 μm. The spunbond nonwoven material may comprise fibers having an average diameter of at least 5 μm, such as 5 μm to 30 μm, or even less than 20 μm, such as 10 μm to 20 μm. The meltblown nonwoven material may comprise fibers having an average diameter of at least 0.1 μm, such as at least 0.25 μm, or from 0.1 μm to 15 μm, such as from 0.25 μm to 10 μm or from 1 μm to 5 μm. To improve the bond strength between the filaments and the first nonwoven and/or the second nonwoven, the nonwoven may comprise binder fibers, such as bicomponent fibers comprising a binding polymer having a lower melting point than the other component. The bicomponent fiber may be a sheath-core bicomponent fiber. In the binder fiber in the form of a sheath-core bicomponent fiber, the sheath may comprise a polymer having a melting point at least 20 ℃ lower than the melting point of the polymer in the core. The core may comprise polyester and have a melting point of at least 220 ℃. Furthermore, the melting point of the sheath may be below 200 ℃, for example 110 ℃ to 190 ℃. The surface weight of the first nonwoven and/or the second nonwoven may be 1g/m ² To 50g/m ² For example 5g/m ² To 30g/m ² Or 5g/m ² To 20g/m ² Or even 8g/m ² To 15g/m ² . Nonwoven materials having too low a surface weight may not provide sufficient elasticity to provide the desired comfort. However, artificial feathers comprising nonwoven materials with too high a surface weight may be perceived as heavy and dense.

Filaments are typically somewhat thicker to provide the desired elastic properties. Its maximum cross-sectional dimension may be from 0.05mm to 1mm, for example from 0.1mm to 0.6mm. Typically, the filaments are circular in cross-section. For filaments having a circular cross-section, the diameter may be 0.05mm to 1mm, for example 0.1mm to 0.8mm, or 0.4mm to 0.6mm. Too thin filaments may not provide sufficient elasticity to provide the desired comfort. The filaments may be hollow filaments, such as hollow bicomponent fibers. The hollow filaments are lighter than solid monofilaments having the corresponding diameter, for example 25% to 50% lighter. Hollow filaments can still provide desirable elastic properties. However, the bending properties of hollow filaments are slightly different from those of solid filaments. Indeed, it has been found, at least in some embodiments, that the feel of an artificial feather having hollow filaments arranged along one extension of the strip (e.g. centrally arranged along the longitudinal extension of the strip) may better match the feel of a natural feather than the feel of an artificial feather having solid filaments.

To facilitate bonding of the filaments to the nonwoven sheet, the filaments may be bicomponent fibers, such as sheath-core bicomponent fibers. In embodiments where the filaments are sheath-core bicomponent fibers, the core may comprise polyester and have a melting point of at least 220 ℃. Furthermore, the melting point of the sheath may be below 200 ℃, for example 110 ℃ to 190 ℃.

According to another aspect, an artificial down fill material is provided that includes artificial down clusters and artificial feathers. Each of the down clusters comprises a plurality of filaments arranged side-by-side in a bundle. The filaments are bonded together at bonding locations, preferably melt bonded together at bonding locations. At least 50% by weight of the total amount of filaments is a self-crimping multicomponent filament. Preferably, the artificial down fill material comprises 60 to 95 wt% artificial down clusters and 5 to 30 wt% artificial feathers. According to one embodiment, each artificial feather comprises a first sheet of a first nonwoven material and filaments arranged along one extension of the sheet, the filaments being bonded to the first sheet. Furthermore, aspects of artificial feathers have been described above. According to one embodiment, at least 50% by weight of the total amount of the multicomponent filaments in the artificial down cluster have at least three corners in cross-section. Furthermore, the bundles of filaments are optionally textured. Additional aspects of the artificial down clusters have been described above.

According to another aspect, there is provided an article filled with the artificial down fill material of the invention. The article may be selected from pillows, quilts, sleeping bags and cushion members (e.g., sofa cushions). According to one embodiment, the article is a pillow, sofa cushion or quilt, for example a pillow.

The artificial down cluster may be provided by bonding filaments in the yarn at bonding locations extending in the longitudinal direction of the yarn and cutting the yarn between the bonding locations. As already explained above, filaments include self-crimping multicomponent filaments. Typically, at least 50% by weight of the total amount of filaments is a self-crimping multicomponent filament. Preferably, at least 75 wt%, such as at least 90 wt% or at least 95 wt% of the total amount of filaments in the down cluster are self-crimping multicomponent filaments. At least 50 weight percent of the total cross-section of the multicomponent filaments has at least three corners. In the resulting artificial down cluster, the filaments are arranged side by side in bundles. The yarn comprising filaments may optionally be textured. The bundles of filaments are thus optionally textured.

According to another aspect, there is thus provided a method for providing an artificial down fill material. The artificial down fill material comprises artificial down clusters. Each of the down clusters comprises a plurality of filaments arranged side-by-side in a bundle. The bundles of filaments are optionally textured. Further, the filaments are bonded together at bonding locations, preferably melt bonded together at bonding locations. The filaments are self-crimping multicomponent filaments. At least 50 weight percent of the total cross-section of the multicomponent filaments has at least three corners. The method comprises the following steps:

-combining filaments in a yarn, the yarn optionally being textured at a combining location extending in the longitudinal direction of the yarn, wherein the yarn comprises filaments that are self-crimping multicomponent filaments, at least 50 wt% of the total amount of multicomponent filaments having at least three corners in cross-section; and

-cutting the yarn between bonding locations to provide bundles of filaments arranged side by side to provide said artificial down filling material.

By first bonding the filaments in the yarn at bonding locations extending in the longitudinal direction of the yarn and then cutting the yarn between the bonding locations to provide bundles of filaments arranged side by side, an artificial down fill material can be efficiently produced. In such a method, no treatment is required, such as collecting and/or arranging the short fibers to be combined into a fiber cluster. In the method of the present invention, the continuous filaments can be wound onto and unwound from rolls in the production and processing of the filaments to ultimately provide the artificial down fill material of the present invention, thereby providing an efficient process.

The aspects of the filaments and the clusters of artificial down respectively described above in relation to the artificial down filling material are equally applicable to the method of providing the artificial down filling material.

Yarns comprising multicomponent filaments can be obtained by spinning (i.e., extruding) a first melt comprising at least a first thermoplastic polymer and a second melt comprising a second thermoplastic polymer into multicomponent filaments, such as bicomponent filaments. Typically, the die includes a plurality of openings such that a plurality of multicomponent filaments, i.e., bundles of filaments, are provided to form a yarn. After extrusion, the filaments may be processed in multiple steps to provide a pile yarn comprising self-crimping filaments. The bundles of filaments are optionally textured. In addition, the process bundles cause the filaments to entangle to form a yarn, but not twist, i.e., the filaments are untwisted.

According to one embodiment, the method of providing an artificial down fill material further comprises the steps of:

extruding at least a first melt comprising a first thermoplastic polymer and a second melt comprising a second thermoplastic polymer into a plurality (i.e. a bundle) of multicomponent filaments, such as bicomponent filaments, through a die having an opening with at least three lobes (preferably the opening is trilobal), the first thermoplastic polymer and the second thermoplastic polymer having different yield behaviors;

-drawing and solidifying the multicomponent filaments to provide a plurality of self-crimping multicomponent filaments;

-optionally deforming and/or drawing the drawn multicomponent filaments; and

-collecting a plurality of multicomponent filaments entangled into a pile yarn.

The multicomponent filaments may be drawn and/or textured by a gas jet. As the skilled person realizes, other gases such as nitrogen and carbon dioxide may also be used in the jet in deforming the multicomponent filaments. The gas jet may be oriented perpendicular to the longitudinal extension of the multicomponent filaments. Alternatively, the gas jets may be oriented parallel to the longitudinal extension of the multicomponent filaments. In addition to stretching and/or texturing the multicomponent filaments, the gas jets can entangle them, thereby providing a yarn.

As already described above, the first thermoplastic polymer and/or the second thermoplastic polymer is/are distributed eccentrically over the cross-section of the multicomponent filaments. Which may be distributed side by side. In addition, the multicomponent filaments may be bicomponent filaments. The first thermoplastic polymer and the second thermoplastic polymer may have at least one of: different stress relaxation responses, different melt flow rates, different elastic ratios, and different intrinsic viscosities, e.g., different intrinsic viscosities.

Although the present invention has been described above with reference to specific embodiments, the invention is not intended to be limited to the specific forms set forth herein. Rather, the invention is limited only by the accompanying claims and, other embodiments than the specific above are equally possible within the scope of these appended claims.

In the claims, the term "comprising/comprising" does not exclude the presence of other elements or steps. Additionally, although individual features may be included in different claims, these may possibly be advantageously combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous.

Furthermore, singular references do not exclude a plurality. The terms "first," "second," and the like, without any numerical modification, do not exclude a plurality.

Drawings

These and other aspects, features and advantages that the invention is capable of to achieve will be apparent from and elucidated with reference to the following description of embodiments of the invention, with reference to the accompanying drawings, in which:

FIG. 1 shows a photograph of an artificial down cluster according to one embodiment;

FIG. 2 shows a photograph of an artificial down cluster according to one embodiment;

fig. 3a shows an artificial down cluster according to the embodiment in fig. 1.

Fig. 3b shows an artificial down cluster according to the embodiment in fig. 2.

Fig. 4a to 4c show cross sections of filaments having a trilobal cross section according to three embodiments;

fig. 5a to 5c show photographs of a bundle comprising:

a) Bicomponent filaments having a trilobal cross-section;

b) Conventional filaments with circular cross-section (control); and

c) Filaments with dog bone-like cross section (control);

FIG. 6 shows a photograph of an artificial feather to be mixed with an artificial down cluster to provide an artificial down fill material, according to one embodiment;

fig. 7 illustrates an apparatus for processing yarn into a human down cluster according to one embodiment.

Detailed Description

In fig. 1, a photograph of an artificial down cluster 1 is provided. The down cluster comprises about 300 filaments 10 arranged side by side in a bundle. The filaments are fusion bonded together at a bonding location 20 that is substantially centered. The filaments were 60mm long bicomponent filaments which were self-crimping and had a cross section with three corners 211 (see fig. 4 c). Filament 10 is a side-by-side bicomponent fiber comprising 50 wt.% PET (3 wt.% silicone additive from Eastman-DowMB50-010 Masterbatch F61 HC) and 50 wt% PBT (B2550 from BASF). The bundles of filaments are textured.

In fig. 2, a photograph of an artificial down cluster 1 is provided. The down cluster comprises about 300 filaments 10 arranged side by side in a bundle. The filaments are fusion bonded together at a bonding location 20 closer to one end of the filaments 10. The filaments are of the same kind as in fig. 1. The bundles of filaments are textured.

As schematically shown in fig. 3a and 3b, the down cluster 1 in fig. 1 and 2, respectively, comprises a plurality of filaments 10 arranged side by side in a bundle. The filaments are fusion bonded together at a bonding location 20. In the embodiment shown in fig. 3a, the bonding location 20 is substantially centered, whereas in the embodiment shown in fig. 3b the bonding location 20 is closer to one end of the filament 10.

As can be seen in fig. 4, which shows a cross section of a bicomponent filament with three corners 211, the two components in the bicomponent filament are not symmetrically distributed. Furthermore, as can be seen in this figure, the edges 212 of the connecting corners 211 of the cross section of the filament 10 are concave, i.e. curved inwards towards the centre of the cross section. However, the cross-section of the filament according to the embodiment in fig. 4a is obviously trilobal, the cross-section of the filament according to the embodiment in fig. 4c is more triangular, however the sides of the cross-section are also slightly concave. As can be seen in fig. 4c, the first component 213 and the second component 214 of the bicomponent fiber are arranged side by side.

As can be seen in fig. 5, the bundle comprising filaments 10 having a trilobal cross-section (fig. 5 a) is much more fluffy than the bundle comprising filaments having a circular (fig. 5 b) or flat (fig. 5 c) cross-section.

Furthermore, artificial feathers 100 (see fig. 6) are provided according to the disclosure in PCT/SE 2020/050873. The artificial feather is 60mm long L and 36mm wide W. It comprises a surface weight of 10g/m ² And filaments 120 (0.5 mm in diameter) disposed along the spunbond nonwoven. Filaments 120 are present between two strips 110 of spunbond nonwoven. The strips 110 are bonded together at least along a plurality of bond lines 130 arranged in a fishbone pattern. As can be seen in fig. 6, the filaments 120 have an arcuate shape.

By combining 20 wt.% of such feathers with 80 wt.% of artificial down clusters (60% of the artificial down clusters in fig. 1 and 40% of the artificial down clusters in fig. 2), an artificial down fill material is provided which is 15% lighter by weight than a natural fill material comprising 40 wt.% of natural feathers and 60 wt.% of natural down. In consumer testing, the artificial down fill material provides substantially the same comfort and resiliency as the natural fill material.

As can be seen in fig. 7, yarn 2 comprising filaments 10 that are self-crimping multicomponent filaments 10 can be processed into artificial down cluster 1 by feeding yarn 2 from yarn feeder 520 to tensioner 530 to stretch it. Yarn 2 is then fed to a calender combiner 510 comprising rolls 511, 512, 513. Roller 512 is a heated roller provided with alternating bond tips 515 and insulating pads 516 around its periphery. In the calender-bonding machine 510, filaments 10 in yarn 2 are melt-bonded at bonding locations 20 extending in the longitudinal direction of the yarn 2 by calendering the filaments 10 in yarn 2 between rolls 511, 521. Downstream of the calender bonder 510, the yarns are cut into down clusters 1 by cutting filaments 10 between bonding locations 20 in a staple fiber cutter 550 to provide down clusters 1.

Examples

An artificial down fill material is provided that includes clusters of artificial down and artificial feathers. The artificial down fill material comprises 80 wt.% of an artificial down blend of down clusters (60 wt.% end bonds and 40 wt.% intermediate bonds) and 20 wt.% of artificial feathers. The artificial feather has a surface weight of 10g/m from 60mm long by 18mm wide ² Comprising filaments sandwiched between two nonwoven sheets, the filaments being centrally arranged in the longitudinal extension of the strip. The down cluster comprises 576 self-crimping bicomponent filaments (75 wt.% PET and 25 wt.% PBT) having a linear density of 4.6 dtex and a trilobal cross section. The tufts were 60mm long in the extended state.

The artificial down fill material was subjected to consumer testing, wherein the products with the material (pillow and duvet) were compared with products with natural down and feathers (60% down, 40% feathers) and with synthetic polyester fill, respectively.

Method

Longitudinal user test for 9 weeks

7 to 8 interviewees (total 31) from each of japan, germany, uk and sweden

After agreement with the privacy agreement, all interviewees were sent with 3x full-size duvets and pillow samples for testing. The suit is marked with letters but does not provide information about the material filling (blind test)

The trial involved a 3x 1 hour virtual interview (start, middle and end) and used Indeemo (mobile research platform) to capture the instant experience and video/photo shots throughout the trial.

Sample of

Age, life stage (pre-school age, family, empty-nest elderly) and sex distribution

Low and medium income

Live in urban areas

Mixing of NDF and hypothetical owners

Result-duvet

How comfortable the duvet is sleeping: artificial down fill materials are reported to be slightly uncomfortable compared to natural down/feathers, but comparable to commercially synthetic polyester fill.

When sleeping under the duvet, the duvet fits the body to the extent that: artificial down fill materials are reported to be superior to commercially synthetic polyester fill and comparable to natural down/feathers.

The duvet helps to regulate the temperature throughout the night: all fillers provided similar results, but natural down/feathers were reported to be slightly better.

Results-pillow

How comfortable the pillow is to sleep: artificial down fill materials are reported to be superior to commercially synthetic polyester fill and nearly comparable to natural down/feathers.

When you put their head on the pillow, the pillow compresses to what extent: artificial down fill materials are reported to be comparable to natural down/feathers and different from commercially synthetic polyester fill.

How the pillow recovers after being compressed or flattened: it is reported that the artificial down fill material is more similar to natural down/feathers than to commercially synthetic polyester fill.

Results-pillow and duvet

How the duvet and pillow make sound when moving the body or head: the sound of artificial down fill materials is reported to be similar to that of natural down/feathers and very different from that of commercially synthesized polyester fills.

What filler material is inside: for artificial down fill materials, almost 50% of the material inside is guessed (about 15% for plant-based natural materials such as cotton, the second guess) as natural down/feathers (the corresponding number of natural down/feathers is slightly higher than 60%).

Side-by-side comparison

In side-by-side comparison with natural down/feathers, artificial down fill materials are reported to mimic natural down/feathers well, but are generally somewhat less preferred.

Claims

1. An artificial down fill material comprising artificial down clusters (1), wherein each of the down clusters (1) comprises a plurality of filaments (10) arranged side by side in bundles, the filaments (10) being bonded together at bonding locations (20), preferably melt bonded together at bonding locations (20), wherein at least 50 wt% of the total amount of filaments (10) is a self-wrapping multicomponent filament (10), at least 50 wt% of the total amount of multicomponent filaments (10) having a cross section with at least three corners (211), and wherein the bundles of filaments (10) are optionally textured.

2. The artificial down fill material of claim 1, wherein at least 75 wt%, such as at least 90 wt% or at least 95 wt%, of the cross-section of the total amount of the multi-component filaments (10) has at least three corners (211); and/or wherein at least 75 wt%, such as at least 90 wt% or at least 95 wt% of the total amount of filaments (10) is a self-crimping multicomponent filament (10).

3. The artificial down fill material according to claim 1 or 2, wherein the cross section of the filament (10) has three corners (211); preferably the sides of the cross section connecting the corners (211) are concave.

4. An artificial down fill material according to any one of the preceding claims, wherein each down cluster comprises 50 to 1000 filaments (10), such as 250 to 750 filaments (10).

5. The artificial down fill material according to any one of the preceding claims, wherein:

-the filaments (10) have a linear density of 0.5 dtex to 10 dtex, for example 2 dtex to 5 dtex; and/or

-the filaments (10) are 20mm to 120mm long, for example 30mm to 90mm long, or even 35mm to 80mm long; preferably, the filaments (10) are at least 55mm long.

6. An artificial down filling material according to any one of the preceding claims, wherein the artificial down filling material comprises a first type of artificial down cluster and a second type of artificial down cluster, which two types of clusters differ in the position of the bonding location (20);

Preferably, the bonding locations (20) in the first type of tuft are substantially centered, and the bonding locations (20) in the second type of tuft are closer to one end of the filament (10);

more preferably, in the first type of cluster, the centre of the bonding location (20) is located at a distance from each end of the filaments (10) corresponding to at least 40% of the total length of the filaments (10), and in the second type of cluster, the centre of the bonding location (20) is located at a distance from one end of the filaments (10) corresponding to less than 30% of the total length of the filaments (10).

7. The artificial down fill material according to claim 6, wherein the weight ratio between the first type of clusters and the second type of clusters is in the range of 3:1 to 1:3, such as 2:1 to 1:2; preferably, the artificial down fill material comprises a higher proportion of clusters of the first type than of clusters of the second type, for example 55 to 70 wt% of clusters of the first type and 30 to 45 wt% of clusters of the second type, based on the total weight of artificial down clusters.

8. An artificial down fill material according to any one of the preceding claims, wherein the bonding locations (20) extend along less than 20%, such as less than 10% or less than 5% of the length of the filaments (10).

9. The artificial down fill material according to any one of the preceding claims, wherein the first component of the multicomponent filaments comprises a first thermoplastic polymer and the second component of the multicomponent filaments comprises a second thermoplastic polymer, wherein the first thermoplastic polymer and the second thermoplastic polymer have different yielding behavior such that the multicomponent filaments (10) are self-crimping, wherein the first thermoplastic polymer and/or the second thermoplastic polymer are eccentrically distributed over the cross section of the multicomponent filaments, optionally the multicomponent filaments are bicomponent filaments.

10. The artificial down fill material of claim 9, wherein the first thermoplastic polymer and the second thermoplastic polymer have at least one of: different stress relaxation responses, different melt flow rates, different elastic ratios, and different intrinsic viscosities, e.g., different intrinsic viscosities; preferably, the difference in intrinsic viscosity between the first thermoplastic polymer and the second thermoplastic polymer is at least 0.01dl/g, for example at least 0.03dl/g.

11. The artificial down fill material according to any one of claims 9 to 10, wherein the multi-component filaments (10) are bicomponent filaments (10); and/or wherein in the multicomponent filaments the first thermoplastic polymer is present in an amount of from 20 wt.% to 80 wt.%, e.g., from 25 wt.% to 75 wt.%, and the second thermoplastic polymer is present in an amount of from 80 wt.% to 20 wt.%, e.g., from 75 wt.% to 25 wt.%.

12. The artificial down fill material according to any one of claims 9 to 11, wherein:

-the first thermoplastic polymer is selected from polyethylene terephthalate (PET), modified PET, polybutylene terephthalate (PBT), poly (trimethylene terephthalate) (PTT), copolyesters, polyamides (PA), modified polyamides, copolyamides, polyethylene (PE), polypropylene (PP), polylactic acid (PLA), polybutylene succinate (PBS), polyethylene furandicarboxylate (PEF) and Polyhydroxyalkanoate (PHA); and

-the second thermoplastic polymer is selected from polyethylene terephthalate (PET), modified PET, polybutylene terephthalate (PBT), poly (trimethylene terephthalate) (PTT), copolyesters, polyamides (PA), modified polyamides, copolyamides, polyethylene (PE), polypropylene (PP), polylactic acid (PLA), polybutylene succinate (PBS), polyethylene furandicarboxylate (PEF) and Polyhydroxyalkanoate (PHA);

preferably, the first thermoplastic polymer is PET and the second polymer is PBT; more preferably, the first thermoplastic polymer is PET and the second polymer is PBT, the PBT comprising at least 20 wt.% of the filaments, wherein the weight ratio of PET to PBT optionally exceeds 1:1.

13. The artificial down fill material according to any one of the preceding claims, wherein the artificial down fill material further comprises feathers; preferably, the artificial down filling material comprises 60 to 95 wt% of artificial down clusters (1) and 5 to 30 wt% of feathers.

14. The artificial down filling material according to claim 13, wherein the feathers are artificial feathers (100); preferably, each artificial feather (100) comprises a first sheet (120) of a first nonwoven material and filaments (110) arranged along one extension of the sheet (120), the filaments (110) being bonded to the first sheet (120).

15. An artificial down fill material comprising artificial down clusters (1) and artificial feathers (100), wherein each of the down clusters (1) comprises a plurality of filaments (10) arranged side by side in bundles, the filaments (10) being bonded together at bonding locations (20), preferably melt bonded together at bonding locations (20), wherein at least 50 wt% of the total amount of filaments (10) is a self-curling multicomponent filament (10); preferably, the artificial down filling material comprises 60 to 95 wt% of artificial down clusters (1) and 5 to 30 wt% of artificial feathers (100).

16. The artificial down filling material according to claim 15, wherein each artificial feather (100) comprises a first sheet (120) of a first nonwoven material and filaments (110) arranged along one extension of the sheet (120), the filaments (110) being bonded to the first sheet (120).

17. The artificial down fill material according to claim 15 or 16, wherein at least 50 wt% of the cross-section of the total amount of the multi-component filaments (10) has at least three corners (211), and wherein the bundles of filaments (10) are optionally textured.

18. The artificial down fill material according to any one of claims 15 to 17, wherein at least 75 wt%, such as at least 90 wt% or at least 95 wt%, of the cross-section of the total amount of the multi-component filaments (10) has at least three corners (211); and/or wherein at least 75 wt%, such as at least 90 wt% or at least 95 wt% of the total amount of filaments (10) is a self-crimping multicomponent filament (10).

19. The artificial down filling material according to any one of claims 17 to 18, wherein the cross section of the filament (10) has three corners (211); preferably, the sides of the cross section connecting the corners (211) are concave.

20. The artificial down fill material according to any one of claims 15 to 19, wherein each down cluster comprises 50 to 1000 filaments (10), such as 250 to 750 filaments (10).

21. The artificial down fill material according to any one of claims 15 to 20, wherein:

22. An artificial down filling material according to any one of claims 15 to 21, wherein the artificial down filling material comprises a first type of artificial down cluster and a second type of artificial down cluster, which two types of clusters differ in the position of the bonding location (20);

23. The artificial down fill material according to claim 22, wherein the weight ratio between the first type of clusters and the second type of clusters is in the range of 3:1 to 1:3, such as 2:1 to 1:2; preferably, the artificial down fill material comprises a higher proportion of clusters of the first type than of clusters of the second type, for example 55 to 70 wt% of clusters of the first type and 30 to 45 wt% of clusters of the second type, based on the total weight of artificial down clusters.

24. The artificial down fill material according to any one of claims 15 to 23, wherein the bonding locations (20) extend along less than 20%, such as less than 10% or less than 5% of the length of the filaments (10).

25. The artificial down fill material according to any one of claims 15 to 24, wherein the first component of the multicomponent filaments comprises a first thermoplastic polymer and the second component of the multicomponent filaments comprises a second thermoplastic polymer, wherein the first thermoplastic polymer and the second thermoplastic polymer have different yield behaviors such that the multicomponent filaments (10) are self-crimping, wherein the first thermoplastic polymer and/or the second thermoplastic polymer are eccentrically distributed over a cross section of the multicomponent filaments, optionally the multicomponent filaments are bicomponent filaments.

26. The artificial down fill material of claim 25, wherein the first thermoplastic polymer and the second thermoplastic polymer have at least one of: different stress relaxation responses, different melt flow rates, different elastic ratios, and different intrinsic viscosities, e.g., different intrinsic viscosities; preferably, the difference in intrinsic viscosity between the first thermoplastic polymer and the second thermoplastic polymer is at least 0.01dl/g, for example at least 0.03dl/g.

27. The artificial down fill material according to any one of claims 25 to 26, wherein the multi-component filaments (10) are bicomponent filaments (10); and/or wherein in the multicomponent filaments the first thermoplastic polymer is present in an amount of from 20 wt.% to 80 wt.%, e.g., from 25 wt.% to 75 wt.%, and the second thermoplastic polymer is present in an amount of from 80 wt.% to 20 wt.%, e.g., from 75 wt.% to 25 wt.%.

28. The artificial down fill material according to any one of claims 25-27, wherein:

29. An article of manufacture filled with the artificial down filling material according to any one of claims 1 to 28, the article of manufacture being selected from pillows, quilts, sleeping bags and cushion members, such as sofa cushions; preferably the article is a pillow, sofa cushion or quilt, such as a pillow.

30. A method for providing an artificial down fill material comprising artificial down clusters (1), wherein each of the down clusters (1) comprises a plurality of filaments (10) arranged side by side in bundles, the bundles of filaments (10) optionally being textured, the filaments (10) being bonded together at bonding locations (20), preferably melt bonded together at bonding locations (20), wherein at least 50 wt% of the total amount of filaments (10) is a self-curling multicomponent filament (10), at least 50 wt% of the total amount of multicomponent filaments (10) having a cross section with at least three corners (211), the method comprising:

-combining filaments (10) in a yarn (2), the yarn (2) optionally being textured at a combining location (20) extending in the longitudinal direction of the yarn (2), wherein the yarn (2) comprises a total of at least 50 wt% of filaments (10) being self-crimping multicomponent filaments (10), at least 50 wt% of the total of the multicomponent filaments (10) having a cross-section with at least three corners (211); and

-cutting the yarn (2) between the bonding locations (20) to provide bundles of the filaments (10) arranged side by side to provide the artificial down filling material.

31. The method according to claim 30, wherein:

-the cross section of the filament (10) has three corners (211); preferably, the sides of the section connecting the corners (211) are concave; and/or

-each down cluster comprises 50 to 1000 filaments (10), for example 100 to 500 filaments (10); and/or

-the filaments (10) are 20mm to 120mm long, e.g. 30mm to 90mm long, or even 35mm to 80mm long.

32. The method of claim 30 or 31, wherein the first component of the multicomponent filament comprises a first thermoplastic polymer and the second component of the multicomponent filament comprises a second thermoplastic polymer, wherein the first thermoplastic polymer and the second thermoplastic polymer have different yield behaviors such that the multicomponent filament (10) is self-crimping, wherein the first thermoplastic polymer and/or the second thermoplastic polymer is eccentrically distributed over a cross-section of the multicomponent filament, optionally the multicomponent filament is a bicomponent filament.

33. The method according to claim 32, wherein:

34. A method according to any one of claims 31 to 33, wherein said artificial down filling material comprises a first type of artificial down cluster and a second type of artificial down cluster, which two types of clusters differ in the position of said bonding location (20);

more preferably, in the first type of cluster, the centre of the bonding location (20) is located at a distance from each end of the filaments (10) corresponding to at least 40% of the total length of the filaments (10), and in the second type of cluster, the centre of the bonding location (20) is located at a distance from one end of the filaments (10) corresponding to less than 30% of the total length of the filaments (10);

the method further comprises providing and mixing the first type of clusters and the second type of clusters to provide the artificial down fill material.

35. The method of claim 34, wherein the weight ratio between the first type of clusters and the second type of clusters is in the range of 3:1 to 1:3, such as 2:1 to 1:2; preferably, the artificial down fill material comprises a higher proportion of clusters of the first type than of clusters of the second type, for example 55 to 70 wt% of clusters of the first type and 30 to 45 wt% of clusters of the second type, based on the total weight of artificial down clusters.

36. The method according to any one of claims 30 to 35, wherein the method further comprises the steps of:

-extruding a first melt comprising a first thermoplastic polymer and a second melt comprising a second thermoplastic polymer into a plurality of multicomponent filaments (10) through a die having an opening with at least three lobes, preferably the opening is trilobal, wherein the first thermoplastic polymer and the second thermoplastic polymer have different yield behaviors, a first component of the multicomponent filaments (10) comprising the first thermoplastic polymer and a second component of the multicomponent filaments (10) comprising the second thermoplastic polymer;

-drawing and solidifying the multicomponent filaments (10) to provide a plurality of self-crimping multicomponent filaments (10); and

-optionally deforming and/or stretching the drawn multicomponent filaments (10); and

-collecting said plurality of multicomponent filaments (10) as yarns (2) to be combined and cut into artificial down clusters (1).

37. The method of claim 36, wherein the first thermoplastic polymer and/or the second thermoplastic polymer is distributed eccentrically over a cross-section of the multicomponent filament, such as side-by-side; and/or wherein the multicomponent filaments are bicomponent filaments; and/or wherein the first thermoplastic polymer and the second thermoplastic polymer have at least one of: different stress relaxation responses, different melt flow rates, different elastic ratios, and different intrinsic viscosities, e.g., different intrinsic viscosities.

38. The method according to any one of claims 36 to 37, wherein the multicomponent filaments (10) are textured and coagulated by gas jets; preferably, the gas jet is oriented perpendicular to the longitudinal extension of the multicomponent filaments (10).