HK1228969B - Volume nonwoven fabric - Google Patents

Description

Nonwoven fabrics that provide volume

Field of the Invention

The present invention relates to a nonwoven fabric comprising a bulk-providing material, in particular fiber balls, down and/or fine feathers. The invention also relates to the use of the nonwoven fabric as a filling material for textile materials such as blankets, clothing and/or upholstered furniture, and to a method for producing the nonwoven fabric.

Background Art

A variety of filling materials are known for use in textile applications. For example, fine feathers, down, and animal hair, such as wool, have long been used to fill blankets and clothing. Filling materials made from down are very comfortable to use due to their excellent thermal insulation and low weight. However, these materials have the disadvantage that they only adhere slightly to each other.

Fiber balls are an alternative to using these filling materials. The fibers contained in the fiber balls are more or less spherically intertwined with each other and usually have a shape that is approximately spherical. For example, the fiber balls described in EP0203469A can be used as filling materials or decorative materials. These fiber balls are composed of spirally bent and wound polyester fibers, with a length of about 10 to 60 mm and a diameter between 1 and 15 mm. The fiber balls are elastic and can insulate heat. Similar to down, feathers and animal hair, the disadvantage of the fiber balls is that they have only slight adhesion to each other. Because the very small adhesion of the fiber balls will cause the fiber balls to slide, the fiber balls are in a very loose state in the textile material, so this type of fiber ball is not suitable as a filling material for the textile material. In order to prevent sliding in the textile material, the fiber balls are usually sewn.

Using fiber fleece or nonwovens as filling material is another alternative to using down and animal hair. Nonwovens are items made of fibers of finite length (staple fibers), filaments (looped fibers) or cut yarns of any type and origin, which can be combined into fleece (fiber cloth) in any way and bonded to each other in any way.

The disadvantage of conventional fiber fleece or nonwovens is that they have lower loft than bulk filling materials such as down, and the thickness of common nonwovens tends to become thinner over time.

Summary of the Invention

The present invention aims to provide a nonwoven fabric that not only provides excellent thermal insulation but also exhibits excellent softness, high bulk, high compression resilience, low weight, and adaptability to the object being filled. Furthermore, the nonwoven fabric exhibits sufficient stability, enabling, for example, handling as a roll. In particular, the nonwoven fabric can be cut and rolled. Furthermore, a method for manufacturing the nonwoven fabric is provided, as well as the use of the nonwoven fabric as a filling material in textile materials such as blankets, clothing, and/or upholstered furniture.

The problem is solved by a nonwoven fabric comprising a bulk-providing material, in particular fiber balls, down and/or fine feathers, wherein the maximum tensile strength of the nonwoven fabric in at least one direction is at least 0.3 N/5 cm, in particular 0.3 N/5 cm to 100 N/5 cm, measured in accordance with DIN EN 29 073-3, at a mass per unit area of 50 g/m ² .

According to the present invention, the term "volume-providing material" should be understood in a conventional sense. Specifically, a volume-providing material is understood to include a material having an average density of 0.01 g/L to 500 g/L, preferably an average density of 1 g/L to 300 g/L, and particularly 1.5 g/L to 200 g/L. According to the present invention, fiber balls are preferably used as the volume-providing material. However, other volume-providing materials, such as down, fine feathers, aerogels, and/or foams, may also be used.

Compared to known products made of bulk-enhancing materials, the nonwoven fabric according to the present invention is characterized by superior maximum tensile strength. For example, the tensile strength can be adjusted so that the nonwoven fabric can be easily produced, further processed, and used as a roll material. The nonwoven fabric can be cut and rolled. Furthermore, the nonwoven fabric can be washed without losing its functionality.

Furthermore, the nonwoven fabric according to the present invention is characterized by good softness, high bulk, high compression elasticity, good rebound ability, light weight, high insulation ability, and good adaptability to the object being filled.

Surprisingly, it has been found that when a carding method is used to produce a bulky nonwoven raw material, particularly when producing a raw material comprising fiber balls, down, fine feathers and/or foam pieces, a nonwoven fabric according to the present invention can be obtained. Consequently, it has been unexpectedly discovered that carding of such raw materials, particularly when using a carding machine having at least one pair of licker-in rollers, allows the material to be efficiently opened, mixed and oriented without damaging the material. This is surprising because the fiber balls, down and/or fine feathers used as raw materials are very delicate, so it is generally assumed that the carding process would damage the raw materials, thereby impairing the stability and functionality of the final product. The licker-in rollers configured in pairs have the advantage that the metal spikes can mesh with each other. The meshing of the metal spikes allows a dynamic screen to be formed, thereby separating and evenly distributing the nonwoven raw materials.

Furthermore, in the case of fiber balls, processing with paired licker-in rollers results in a loose fiber structure without compromising the overall ball shape. The fibers can be pulled out of the balls, allowing them to protrude from the surface while remaining attached to the balls. This is beneficial because the pulled fibers enhance the anchoring between the individual balls, thereby increasing the tensile strength of the nonwoven fabric. Furthermore, a matrix can be formed from individual fibers, with the balls embedded in the matrix, thereby enhancing the softness of the nonwoven fabric.

However, it has also been found that the carding method enables the raw material to be evenly distributed on the lay belt and a very uniform nonwoven fabric can be obtained in which the bulk-providing material is evenly distributed. The uniform distribution of the bulk-providing material has great advantages in terms of the insulating capacity and softness of the nonwoven fabric.

As described above, the nonwoven fabric according to the invention is characterized in that it has an unexpectedly good adjustable stability. According to DIN EN 29 073-3, the nonwoven fabric has a maximum tensile strength of at least 0.3 N/5 cm, in particular ^0.3 N/5 cm to 100 N/5 cm, in at least one direction at a surface weight of 50 g/m 2, which has proven to be advantageous for many applications. In addition, the nonwoven fabric according to the invention advantageously has a great resilience. Therefore, the nonwoven fabric preferably has a resilience of greater than 50%, 60%, 70%, 80% and/or greater than 90%, wherein the resilience is measured by the following means and methods:

1) Stack six samples together (10x10cm)

2) Measure height with a folding ruler

3) Load the sample with an iron plate (1300g)

4) After 1 minute of loading, measure the height with a folding ruler

5) Remove weight

6) After 10 seconds, measure the height of the sample with a folding ruler

7) After 1 minute, measure the height of the sample with a folding ruler

8) Calculate the recovery rate by the ratio of the value at point 7 to the value at point 2

The high stability of the nonwoven fabric enables it to be easily rolled up, for example as a roll, and processed further.

Furthermore, the nonwoven fabric is characterized by excellent thermal insulation capabilities, good softness, high bulk, high compression elasticity, low weight, and good adaptability to the object being filled.

If fiber balls are used as the bulk-providing raw material for nonwoven fabrics, their structure and shape will vary depending on the material used and the desired properties of the nonwoven fabric. In particular, the term "fiber ball" should be understood to refer to both spherical and nearly spherical shapes, such as irregular and/or deformed spherical shapes, such as flattened spheres. It has been found that spherical or nearly spherical needles can exhibit very good performance in terms of fuzzing and thermal insulation.

Furthermore, the fibers can be arranged generally mainly on the spherical shell, with relatively few fibers arranged in the center of the fiber sphere. However, it is also conceivable that the fibers are evenly distributed within the fiber sphere and/or a fiber gradient exists.

It is also conceivable that the fiber balls contained in the nonwoven fabric according to the present invention contain fibers with a spherical twist and/or a fuzzy structure. In order to ensure a good overall bonding, curled fibers are more advantageous. The fibers can be random or have a certain regularity.

According to one embodiment of the present invention, the fibers within the interior of a single fiberball are entangled, while the fibers in the outer layer of the fiberball are arranged in a spherical shape. In this embodiment, the outer layer is significantly smaller than the diameter of the fiberball. This further enhances the softness of the fiberball.

The form of the fibers present in the fiber ball is essentially unimportant, as long as they are suitable for forming fiber balls by, for example, suitable surface structure and fiber length. Preferably, the fibers of the fiber ball are selected from the group consisting of staple fibers, threads and/or yarns. Here, as distinguished from filaments that theoretically have infinite length, staple fibers are understood to be fibers with a finite length, preferably a length of 20 mm to 200 mm. Threads and/or yarns also preferably have a finite length, in particular a length of 20 mm to 200 mm. The fibers can be presented as single-component filaments and/or composite filaments. The fineness of the fibers can also vary. Preferably, the average fineness range of the fibers is 0.1 to 10 dtex, preferably 0.5 to 7 dtex.

The fiber balls can essentially consist of the most diverse fibers. Thus, the fiber balls can comprise or consist of natural fibers, for example wool fibers; and/or artificial fibers, for example fibers made of polyacrylamide, polyacrylonitrile, preoxidized PAN, PPS, carbon, glass, polyvinyl alcohol, viscose, cellulose, cotton polyamide, polyamideimide, polyamide, in particular polyamide 6 and polyamide 6.6, PULP, preferably polyolefins, particularly preferably polyesters, in particular polyethylene terephthalate, polyethylene naphthalate and polybutylene terephthalate, and/or mixtures thereof. According to a preferred embodiment, fiber balls made of wool fibers are used. In this way, nonwovens with particularly stable shape and particularly good insulating properties can be obtained. According to another preferred embodiment, fiber balls made of polyester are used for particularly good compatibility with other components within the nonwoven fabric or in a nonwoven fabric composite.

The proportion of the fiber balls in the nonwoven fabric is preferably at least 20 wt.%, more preferably 25 to 100 wt.%, particularly 30 to 90 wt.%, relative to the total weight of the nonwoven fabric.

If down and/or feathers are used as the bulk-providing material according to the invention, their proportion in the nonwoven fabric is, for example, 0 to 90 wt.%, preferably 20 to 70 wt.%, or at least 50 wt.%. According to the invention, the term "down and/or feathers" is understood in a conventional sense. In particular, down and/or feathers are understood to mean feathers with a short quill and very soft, long, radially arranged barbs that are essentially free of barbs.

According to a preferred embodiment of the present invention, the nonwoven fabric comprises a heat-sensitive material which is used in the form of fibers or powder during the production of the nonwoven fabric. According to the present invention, preferably, a binder fiber is used. It can be a component of a fiber ball or present as another fiber component in a fiber cloth or in the resulting nonwoven fabric. Conventional binder fibers used for this purpose can be used as binder fibers. The binder fibers can be single fibers or multicomponent fibers. According to the present invention, particularly suitable binder fibers are fibers from the following groups:

Fibers whose melting point is lower than that of the bulk-providing material to be bonded, preferably below 250° C., in particular from 70 to 230° C., most preferably from 125 to 200° C. Suitable fibers are in particular thermoplastic polyesters and/or copolyesters, in particular PBT; polyolefins, in particular polypropylene, polyamide, polyvinyl alcohol; or copolymers and mixtures thereof.

• Binder fibers, such as undrawn polyester fibers.

Particularly suitable binder fibers according to the present invention are multicomponent fibers, preferably bicomponent fibers, and in particular core/sheath fibers. Core/sheath fibers comprise at least two fiber materials having different softening and/or melting temperatures. Core/sheath fibers are preferably composed of these two fiber materials. The component with the lower softening and/or melting temperature is present on the fiber surface (sheath), while the component with the higher softening and/or melting temperature is present in the core.

For core/shell fibers, the bonding function can be achieved by the material disposed on the fiber surface. A wide variety of materials can be used for the shell. According to the present invention, the most preferred shell materials are PBT, PA, copolyamides, or copolyesters. Similarly, a wide variety of materials can be used for the core. According to the present invention, the most preferred core materials are PET, PEN, PO, PPS, or aromatic PA and PES.

The advantage of the presence of bonding fibers is that the bulk-providing material within the nonwoven fabric can be bound together by the bonding fibers, thereby enabling the use of a textile sheath filled with a nonwoven fabric without the bulk-providing material being significantly displaced or without forming cold bridges due to the lack of filling material.

For example, the binder fibers may be contained within fiber balls. Alternatively or additionally, they may be present as a separate fiber component in the nonwoven fabric. Preferably, the binder fibers have a length of 0.5 to 100 mm, more preferably 1 to 75 mm, and/or a fineness of 0.5 to 10 dtex. According to particularly preferred embodiments of the present invention, the binder fibers have a fineness of 0.9 to 7 dtex, more preferably 1.0 to 6.7 dtex, and in particular 1.3 to 3.3 dtex.

The proportion of binder fibers in the nonwoven fabric can be adjusted according to the type and quantity of the other components of the nonwoven fabric and the desired stability of the nonwoven fabric. If the proportion of binder fibers is too low, the stability of the nonwoven fabric deteriorates. If the proportion of binder fibers is too high, the nonwoven fabric will be too stiff overall, which will impair its softness. Practical tests have revealed that a good compromise between stability and softness can be achieved when the proportion of binder fibers is between 5 and 50 wt.%, preferably between 7 and 40 wt.%, and particularly preferably between 10 and 35 wt.%. In this way, the nonwoven fabric obtained is sufficiently stable to be rolled up and/or folded. This makes the handleability and further processing of the nonwoven fabric easier. In addition, this nonwoven fabric is washable. For example, its stability is sufficient to withstand three home washes at 40°C without decomposing.

The binder fibers can be bonded to each other and/or to other components of the nonwoven fabric by heat fusion. Particularly suitable methods have been passage through a hot air tunnel oven, a hot air double-belt oven, and/or hot calendering using heated, smooth, or etched rollers on a drum through which hot air flows. The advantage of using a double-belt hot air oven is that the binder fibers can be activated particularly effectively while simultaneously smoothing the surface and maintaining bulk.

Alternatively, the nonwoven fabric can also be consolidated by subjecting the optionally pre-consolidated fiber cloth to liquid jets, preferably water jets, at least once per side.

According to another embodiment of the present invention, the nonwoven fabric includes additional fibers that are not in the form of fiber balls and can modify the properties of the nonwoven fabric in a desired manner. Because these fibers are not in the form of fiber balls, they can have the most diverse surface properties, and in particular, they can be smooth fibers. As mentioned above, binder fibers can be used as additional fibers. However, it is also conceivable to use non-binder fibers. Thus, for example, to provide a nonwoven fabric with a certain gloss, silk fibers can be used as additional fibers. It is also conceivable to use polypropylene, polyacrylonitrile, pre-oxidized PAN, PPS, carbon, glass, polyaramid, imide, melamine resin, phenolic resin, polyvinyl alcohol, polyamide (polyamide), in particular polyamide 6 and polyamide 6.6, polyolefins, viscose, cellulose, and preferably polyesters, in particular polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBTE), and/or mixtures thereof.

Advantageously, the proportion of the additional fibers in the nonwoven fabric is 5 to 80 wt.%, in particular 20 to 70 wt.%. Preferably, the additional fibers have a length of 1 to 200 mm, preferably 5 to 100 mm, and/or a titer of 0.5 to 20 dtex.

According to another preferred embodiment of the present invention, the nonwoven fabric includes a phase change material. A phase change material (PCM) is a material whose potential heat of fusion, dissolution, or absorption is significantly greater than the amount of heat it can store based on its normal specific heat capacity (without a phase change effect). The PCM can be included in the material component in particulate and/or fibrous form and bonded to other components of the nonwoven fabric, for example, via adhesive fibers. The presence of the PCM can support the insulating function of the nonwoven fabric.

The polymer used to produce the fibers of the nonwoven fabric may include at least one additive selected from the group consisting of a pigment, an antistatic agent, an antimicrobial agent such as copper, silver, or gold, or a hydrophilic or hydrophobic treatment additive in an amount ranging from 150 ppm to 10 wt.%. The additives used in the polymer may be tailored to meet customer-specified requirements.

The nonwoven fabric according to the present invention may also include an additional layer. It is contemplated that the additional layer may be configured as a reinforcement layer, for example in the form of a scrim and/or comprise reinforcing filaments, a nonwoven fabric, a woven fabric, a knitted fabric, and/or a laid net. Preferred materials for the additional layer are plastic, such as polyester, and/or metal. Advantageously, the additional layer may be provided on the surface of the nonwoven fabric.

The thickness of the nonwoven fabric is preferably selected according to the desired insulating effect and the materials used. Generally, good results are achieved with thicknesses in the range of 2 mm to 100 mm as measured according to test procedure EN 29073-T2.

The surface weight of the nonwoven fabric according to the invention can be adjusted depending on the desired application. Surface weights in the range of 15 to 1500 g/m ² , preferably 20 to 1200 g/m ² and in particular 30 to 1000 g/m ² , measured according to DIN EN 29 073, have proven to be desirable for many applications.

In addition, the reinforced nonwoven fabric can undergo chemical bonding or refining, such as anti-pilling treatment, hydrophobic or hydrophilic treatment, antistatic treatment, treatment to improve fire resistance and/or change tactile properties or gloss; mechanical treatment, such as roughening, shrinkage prevention, sanding with sandpaper or tumbler treatment; and/or treatment for changing the appearance, such as coloring or embossing.

The nonwoven fabric according to the invention is highly suitable for the production of a wide variety of textile products, in particular products that offer excellent thermophysiological comfort and are lightweight. Therefore, another subject matter of the present invention is the use of the nonwoven fabric as a shaping material, for example, as upholstery material and/or filling material for clothing, chairs and sofas, bedspreads, mattresses, as filter paper and/or absorbent pads, as a gasket, a foam substitute, a bandage, or as a fire-fighting material.

Furthermore, the present invention relates to the use of a carding process to produce the above-mentioned nonwoven fabric.

It has been found that the nonwoven fabric according to the invention can be produced particularly efficiently when the opening and distribution of the nonwoven fabric material is achieved by means of licker-in rollers and/or scalpel belts. This method allows for a very uniform laying of the nonwoven fabric raw material, for example on a laying belt, and results in an exceptionally homogeneous nonwoven fabric in which the bulk-generating fiber material is very uniformly and evenly distributed. This is surprising, as it would generally be expected that delicate fiber balls or down, for example, would be destroyed during treatment with licker-in rollers and/or scalpel belts.

Practical tests have revealed that particularly good results can be achieved using the method according to the present invention when one or more of the following steps are included. The raw material can be treated as evenly as possible using at least one carding machine, wherein the raw material includes a bulk-providing material and optionally other components, wherein the carding machine includes at least one pair of licker-in rollers in which the fiber raw material can be opened and mixed with each other. After this, the fibers can be formed into a nonwoven fabric using conventional methods, for example on a screen belt, screen drum and/or conveyor belt. The nonwoven fabric thus formed can then be reinforced using conventional means and methods. According to the present invention, thermal reinforcement using a belt furnace, for example, has proven to be particularly suitable because using this method can avoid undesirable compression of the nonwoven fabric, a problem that would arise if reinforcement were performed using a water jet, for example. The use of a double-belt hot air stove has proven to be particularly suitable. The advantage of using this type of hot air stove is that it can smooth the surface and maintain volume while activating the bonding fibers particularly effectively.

According to a preferred embodiment of the present invention, fibers and fiber balls can be processed in a nonwoven fabric forming unit having at least two licker-in rollers to effectively open and mix the fibers and fiber balls. According to a preferred embodiment of the present invention, the licker-in rollers are arranged in a row. Thus, the licker-in rollers are advantageously arranged in at least one row. Arranging the licker-in rollers in at least one row has the advantage that the metal spikes of adjacent licker-in rollers can intermesh. Thus, each roller simultaneously forms a pair with its adjacent roller, creating a dynamic sieve. These rows can also be arranged in pairs (double rows) to effectively open and mix the fibers and fiber balls. Thus, the licker-in rollers can advantageously be arranged in at least one double row. It is also conceivable to pass at least a portion of the fiber material through the same licker-in roller multiple times using a return system. For example, an endless circulating belt can be used for the return transport. It is advantageously arranged between two rows of licker-in rollers. Alternatively, the circulating belt can pass through several double rows of licker-in rollers, arranged one behind the other or one above the other.

According to a particularly preferred embodiment of the present invention, the method involves a process for forming a nonwoven fabric aerodynamically, i.e., preferably by means of air. Methods based on air-laying processes have proven to be particularly suitable. The basic principle of this method is to feed the fibrous material into an air stream, which allows the fibers to be mechanically distributed in the longitudinal and/or transverse direction of the machine and ultimately allows the fibers to be evenly laid on a conveyor belt with suction at the bottom.

Air can be used in a wide variety of process steps. According to a particularly preferred embodiment of the invention, the entire transport process of the fiber material during the formation of the nonwoven fabric can be carried out aerodynamically, for example by means of an installed air system. However, it is also conceivable that only specific process steps, such as the removal of fibers from the licker-in roller, are supported by additional air.

Practical tests have revealed that when implementing a process based on an air-laying method, it is preferred to perform one or more of the following steps:

Purposefully, the process of handling or loosening the raw material of the nonwoven fabric is directly before the forming process of the nonwoven fabric. The process of mixing with non-fibrous materials (for example down and/or foam parts) is preferably carried out directly during the distribution of fiber material in the nonwoven fabric forming system.

The material can be transported through the feeding and distribution systems to the nonwoven fabric forming unit using air as a transport medium, where the components of the nonwoven fabric raw material are directionally opened, swirled, and simultaneously uniformly mixed and distributed. In order to conveniently control the material supply, each material component is advantageously supplied separately.

After this, the nonwoven raw material is preferably processed using at least two licker-in rollers, which allow the fiber material to be prepared or loosened. Particularly good results are achieved when the nonwoven raw material is passed through a row of rotating shafts equipped with metal spikes (so-called spikes) as licker-in rollers. The meshing of the metal spikes creates a dynamic sieve, which allows for a high throughput.

Advantageously, the nonwoven fabric is formed on a screen belt with suction applied to the bottom. This allows the production of an entangled nonwoven structure with no defined fiber orientation, the density of which depends on the strength of the suction applied to the bottom. Layers can be built up by arranging several nonwoven fabric forming units in a row.

The advantage of aerodynamically forming a nonwoven fabric is that the fibers and optionally other components present in the raw material of the nonwoven fabric can be arranged in an entangled layer, which results in highly isotropic properties. In addition to the structural aspects, this embodiment offers economic advantages, which are derived from the investment volume and the operating costs of the production facility.

According to a specific embodiment of the present invention, the nonwoven fabric can be formed in a plurality of nonwoven fabric forming units arranged in series. Thus, it is conceivable to have a laying belt (e.g., a screen belt with bottom suction) continuously pass through a plurality of nonwoven fabric forming units, with the laying of the nonwoven fabric layer always occurring within said nonwoven fabric forming unit. In this way, a multi-layer nonwoven fabric can be produced.

Nonwovens can be consolidated in conventional ways, for example chemically by spraying with a binder, thermally by melting previously added binder fibers or powders, and/or mechanically, for example by needle punching and/or water jet treatment.

Practical tests have revealed that good results can be obtained, for example, when forming a nonwoven fabric using the apparatus for producing fibrous nonwoven fabrics described in publication WO 2005/044529.

The nonwoven fabric according to the invention is extremely suitable as a shaping material and/or filling material for producing textile materials, such as blankets, clothing and/or upholstered furniture, bed covers, mattresses, filter papers and/or absorbent pads, spacers, foam substitutes, bandages and/or fire-fighting materials.

DETAILED DESCRIPTION

The present invention will be described in more detail below with the help of several examples.

Example 1:

In an air-laid unit from Form Fiber with licker-in rollers for opening the fiber raw material, a 150 g/m² layer consisting of 50 wt.% fiber pellets made of 7 dtex/32 mm siliconized PES (Advansa 732), 30 wt.% fiber pellets made of CoPES binder fibers, and 55 wt.% down and/or feathers from ^Minardi was placed on a support belt and consolidated in a double-belt oven with a 12 mm inter-belt spacing at 155°C. The residence time was 36 seconds. This resulted in a rollable web material.

Example 2:

In a Form Fiber air-laying system with licker-in rollers for opening the fiber raw material, a 120 g/m² layer consisting of 35 wt.% fiber pellets made of 7 dtex/32 mm siliconized PES (Advansa 732) treated with 40% mPCM 28°C PC-temperature enthalpy, 30 wt.% fiber pellets made of CoPES binder fibers, and 35 wt.% down and/or feathers from Minardi was placed on a support belt and consolidated in a ^double -belt oven with a 10 mm inter-belt spacing at 155°C. The residence time was 36 seconds. A rollable web material was obtained.

Example 3:

In a Form Fiber air-laying system with a licker-in roller for opening the fiber raw material, a 150 g/ ^m² layer consisting of 50 wt.% wool fiber balls and 30 wt.% fiber balls made of CoPES binder fiber was placed on a support belt and consolidated in a double-belt oven with a 12 mm inter-belt spacing at 155°C. The residence time was 36 seconds. A rollable web material was obtained.

Example 4:

In a Form Fiber air-laying system with a licker-in roller for opening the fiber raw material, a 150 g/ ^m² layer consisting of 50 wt.% silk fiber pellets and 30 wt.% CoPES binder fiber pellets was placed on a support belt and consolidated in a double-belt oven with a 12 mm inter-belt spacing at 155°C. The residence time was 36 seconds, resulting in a rollable web material.

Example 5:

In an air-laid unit from Form Fiber with a licker-in roller for opening the fiber raw material, a 56 g/ ^m² layer consisting of 80 wt.% fiber balls and 20 wt.% fiber balls made of CoPES binder fibers was placed on a support belt and consolidated in a double-belt oven with a 1 mm inter-belt spacing at 170° C. A rollable web material with a thickness of 6.1 mm was obtained.

Example 6:

In an air-laid unit from Form Fiber with a licker-in roller for opening the fiber raw material, a 128 g/ ^m² layer consisting of 80 wt.% fiber balls and 20 wt.% fiber balls made of CoPES binder fibers was placed on a support belt and consolidated in a double-belt oven with a 4 mm inter-belt spacing at 170° C. A rollable web material with a thickness of 7.5 mm was obtained.

Example 7:

In a Form Fiber system with licker-in rollers for opening the fiber raw material, a 128 g/ ^m² layer consisting of 80 wt.% fiber balls and 20 wt.% fiber balls made of CoPES binder fiber was placed on a support belt and consolidated in a double-belt oven with a 30 mm interbelt spacing (i.e., without fiber cloth) at 170° C. The result was a soft, rollable web material with a thickness of 25 mm.

Example 8:

In a Form Fiber system with licker-in rollers for opening the fiber raw material, a 723 g/ ^m² layer consisting of 80 wt.% fiber balls and 20 wt.% fiber balls made of CoPES binder fiber was placed on a support belt and consolidated in a double-belt oven at 170°C with a 50 mm inter-belt spacing. The result was a stable, rollable web material with a thickness of 50 mm.

Claims (19)

1. A nonwoven fabric in the form of a reinforced sheet, said nonwoven fabric being reinforced by: chemically spraying an adhesive, and/or thermally melting previously added adhesive fibers or adhesive powder, and/or mechanically needle-punching and/or water-jetting treatment, said nonwoven fabric comprising a volume-providing material, said volume-providing material being a fiber ball opened by a needle roller and/or needle band, characterized in that, measured according to DIN EN 29 073, the nonwoven fabric has a maximum tensile strength of at least 0.3 N/5 cm in at least one direction at a surface weight of 50 g/ ^m² . 2. The nonwoven fabric as claimed in claim 1, wherein the maximum tensile strength is from 0.3 N/5 cm to 100 N/5 cm. 3. The nonwoven fabric as claimed in claim 1, wherein the proportion of the fiber balls is at least 20 wt.% relative to the total weight of the nonwoven fabric. 4. The nonwoven fabric as claimed in claim 1, wherein the proportion of the fiber balls is 25 to 100 wt.% relative to the total weight of the nonwoven fabric. 5. The nonwoven fabric as claimed in claim 1, wherein the proportion of the fiber balls is 30 to 90 wt.% relative to the total weight of the nonwoven fabric. 6. The nonwoven fabric according to any one of claims 1-5, wherein the fiber balls comprise polyester fibers and/or mixtures thereof with other fibers. 7. The nonwoven fabric according to claim 6, wherein the polyester fiber is selected from fibers made of the following substances: polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate. 8. The nonwoven fabric according to any one of claims 1-5, wherein the fiber balls are composed of wool. 9. The nonwoven fabric according to any one of claims 1-5, characterized in that the fiber ball comprises adhesive fibers with a length of 0.5 mm to 100 mm. 10. The nonwoven fabric of claim 9, wherein the bonding fiber is configured as a core/shell fiber, wherein the shell comprises PBT, PA, copolyamide or copolyester, and/or the core comprises PET, PEN, PO, PPS or aromatic PA and/or PES. 11. The nonwoven fabric as claimed in claim 9, characterized in that the proportion of adhesive fibers in the nonwoven fabric is in the range of 5 to 50 wt.% relative to the total weight of the nonwoven fabric. 12. The nonwoven fabric as claimed in claim 9, wherein the proportion of adhesive fibers in the nonwoven fabric is in the range of 7 to 40 wt.% relative to the total weight of the nonwoven fabric. 13. The nonwoven fabric as claimed in claim 9, wherein the proportion of adhesive fibers in the nonwoven fabric is in the range of 10 to 35 wt.% relative to the total weight of the nonwoven fabric. 14. The nonwoven fabric according to any one of claims 1-5, wherein the nonwoven fabric comprises a phase change material. 15. The nonwoven fabric as claimed in claim 1, wherein the fiber ball has a spherical or near-spherical shape, and the fibers contained in the fiber ball are more or less spherically intertwined. 16. The nonwoven fabric as claimed in claim 1, characterized in that the fiber is pulled out from the fiber ball such that the fiber protrudes from the surface although it remains connected to the fiber ball. 17. The nonwoven fabric as claimed in claim 1, wherein the nonwoven fabric is reinforced by melting the previously added adhesive fibers or adhesive powder by a thermal method. 18. The application of nonwoven fabrics as described in any one of claims 1-17 in the production of textile materials, wherein the textile materials include blankets, clothing, upholstered furniture, bedspreads, mattresses, filter paper, absorbent pads, gaskets, foam substitutes, bandages, and fire-fighting materials. 19. A method for producing a nonwoven fabric in the form of a reinforced sheet as described in any one of claims 1-17, characterized in that the raw material of the nonwoven fabric comprises a material providing volume, said material providing volume being fiber balls, said raw material of the nonwoven fabric being opened by a barbed roller and/or barbed tape and distributed in a nonwoven fabric forming unit, and then said raw material of the nonwoven fabric being placed on a laying belt and reinforced by: spraying with an adhesive using a chemical method, and/or melting previously added adhesive fibers or adhesive powder using a thermal method, and/or needle punching and/or water jet treatment using a mechanical method.