Method and apparatus for preparing nonwoven

Abstract

The invention relates to a method for producing a nonwoven having at least one nonwoven web made of fibers. The fibers are generated using at least one fiber generating device. The fibers are then laid on at least one laying device to form a nonwoven web. The nonwoven web or nonwoven is consolidated with at least one calendaring roll, and the nonwoven is also consolidated or primarily consolidated with at least one thermal fluid primary consolidation device.

Description

Technical Field

[0001] The invention relates to a method for producing a nonwoven, the nonwoven having at least one nonwoven web made of fibers, wherein the fibers are produced by at least one fiber production device, in particular by at least one spinning beam, and the fibers are subsequently laid on at least one laying device, in particular a laying screen belt, to form the nonwoven web. The invention also relates to an apparatus for producing a nonwoven. Background Art

[0002] Methods and equipment for preparing nonwovens are known in principle with different embodiments in practice. The fibers produced are usually laid on a web laying device to form a nonwoven web and pre-consolidated subsequently, so as to ensure the transportability of the nonwoven web or nonwoven, and to ensure that the nonwoven web is not moved or damaged when transported through the equipment. For further consolidation or main consolidation, the nonwoven is usually delivered to a subsequent device. As a subsequent device for consolidating or main consolidating nonwovens, for example, a calender with at least one calender roller, especially with at least one calender roller pair, is known. Here, a calender roller with an embossing element is usually used, and these embossing elements introduce the embossing pattern consisting of a plurality of embossing portions into the nonwoven during the consolidation process. Although the nonwoven processed with at least one calender is outstanding with its favorable mechanical strength, these nonwovens are often thin in thickness or small in volume. In addition, although the embossed pattern introduced into the nonwoven by the calender is advantageous or necessary in terms of the mechanical properties of the nonwoven, it is disadvantageous from an aesthetic point of view, because the visual properties of the nonwoven are adversely affected thereby. Therefore, as an alternative to the consolidation or main consolidation of the nonwoven, a hot fluid consolidation device or a hot air consolidation device such as a hot air furnace is also known in practice. The nonwoven that is consolidated or mainly consolidated with this consolidation device is usually outstanding with advantageous thickness or bulkiness, but often has undesirable rigidity or poor drapability, and partly has disadvantageous low wear resistance.

[0003] Up to now, an acceptable compromise between sufficient mechanical strength, satisfactory thickness or bulk, low rigidity or satisfactory suspendability and sufficient abrasion resistance could only be achieved by mixing different types of fibers in the nonwoven. However, this is very complex and the corresponding methods are not very flexible to use. Summary of the invention

[0004] In view of this, the technical problem underlying the present invention is to provide a method of the type mentioned at the outset, in which the above-mentioned disadvantages can be effectively and functionally reliably avoided and with which a nonwoven can be produced in particular, which is characterized by advantageous mechanical properties, such as sufficient mechanical strength or surface resistance, sufficient thickness or bulk, low rigidity or satisfactory drape and preferably improved wear resistance, wherein in particular an optimum balance between these nonwoven properties is intended. Furthermore, the technical problem underlying the present invention is to provide a corresponding device for producing a nonwoven and such a nonwoven.

[0005] In order to solve this technical problem, the present invention teaches a method for preparing a nonwoven, which has at least one nonwoven fiber web made of fibers, wherein the fibers are produced by at least one fiber producing device, in particular by at least one spinning beam, and the fibers are subsequently laid on at least one laying device, in particular by a laying screen belt, to form a nonwoven fiber web, wherein the nonwoven fiber web or nonwoven is consolidated by at least one calendering roller, in particular by at least one calendering machine or calendering roller pair having the calendering roller, and wherein the nonwoven is also consolidated or mainly consolidated by at least one hot fluid main consolidation device, in particular by at least one hot air main consolidation device.

[0006] The nonwoven has at least one nonwoven web made of fibers, which means in the context of the present invention in particular that the nonwoven has at least one nonwoven web or nonwoven ply consisting of produced and laid fibers. According to one embodiment, the nonwoven can have only one nonwoven web or nonwoven ply, or can also have a plurality of nonwoven webs or nonwoven plies stacked one above the other, which are combined to form a nonwoven laminate.

[0007] The term "consolidation or main consolidation" refers in the context of the present invention in particular to the consolidation of a nonwoven, which results in the nonwoven having a higher degree of consolidation than pre-consolidation. Within the context of the present invention, a lower or higher degree of consolidation of the nonwoven is achieved with the main consolidation than with consolidation, or a degree of consolidation of the nonwoven which is the same or essentially the same as consolidation is achieved with the main consolidation.

[0008] According to a preferred embodiment of the present invention, nonwoven is prepared into a spunbond nonwoven with at least one spunbond nonwoven web or with at least one spunbond nonwoven ply. It is possible that nonwoven is prepared into a nonwoven laminate consisting of at least two spunbond nonwoven webs or at least two spunbond nonwoven plies. But it is also possible that nonwoven or nonwoven laminate has at least one meltblown nonwoven web or meltblown nonwoven ply. In addition, within the scope of the method according to the present invention, nonwoven is prepared into a nonwoven laminate consisting of at least three, preferably at least four nonwoven webs or nonwoven plies. Each nonwoven web or nonwoven ply can be laid as a spunbond nonwoven web or a nonwoven ply respectively. But, in principle, nonwoven laminate also may be prepared with at least one meltblown nonwoven web or meltblown nonwoven ply. The spunbond nonwoven web or spunbond nonwoven ply is preferably laid down from continuous filaments or crimped continuous filaments, respectively. This will be explained in detail below.

[0009] The term "thermal fluid" within the scope of the present invention refers to a temperature-controlled or heated fluid. Preferably, the thermal fluid is a temperature-controlled or heated gas and particularly preferably hot air. In principle, however, the thermal fluid can also be a temperature-controlled or heated liquid, for example water.

[0010] A particularly preferred embodiment of the method according to the present invention is characterized in that before consolidation with the at least one calender roller and / or before consolidation or main consolidation with the at least one hot fluid main consolidation device, the nonwoven is peeled off from the web laying device. Particularly preferably, after the nonwoven is peeled off from the web laying device, it is not only consolidated with at least one calender roller or with at least one calender having a calender roller, but also consolidated or mainly consolidated with at least one hot fluid main consolidation device. Suitably, the nonwoven is transferred to the calender roller or calender or hot fluid main consolidation device after being peeled off from the web laying device. In principle, within the scope of the present invention, it is also possible to utilize at least one hot air main consolidation device to perform consolidation or main consolidation on or above the web laying screen belt, and preferably then the nonwoven is peeled off from the web laying device.

[0011] It has proven to be particularly advantageous within the scope of the method according to the invention that the consolidation of the nonwoven is carried out by means of the at least one calender roller, in particular by means of at least one calender roller or calender roller pair with the calender roller, before or after the consolidation or main consolidation of the nonwoven by means of the at least one hot fluid main consolidation device, in particular by means of at least one hot air main consolidation device. It is very particularly preferred that the nonwoven, in particular after being peeled off from the web laying device, is first consolidated by means of at least one calender roller, in particular by means of at least one calender roller or calender roller pair with a calender roller, and then consolidated or main consolidated by means of at least one hot fluid main consolidation device, in particular by means of at least one hot air main consolidation device. This sequence of consolidation steps has proven to be particularly effective within the scope of the invention and for solving the technical problem.

[0012] It is recommended that the nonwoven, after being laid on the web laying device and before consolidation or main consolidation, is first pre-consolidated with at least one pre-consolidation device, preferably with at least one hot fluid pre-consolidation device, preferably with at least one hot air pre-consolidation device, preferably connected downstream of the at least one fiber production device or the at least one spinning beam, in particular directly connected downstream thereof. Thus, pre-consolidation is carried out in particular before consolidation with at least one calender roller or with at least one calender and before consolidation or main consolidation with at least one hot fluid main consolidation device. The pre-consolidation step ensures in particular the transportability of the laid nonwoven fiber web or nonwoven and, according to a preferred embodiment, also the removability of the nonwoven from the web laying device and the functionally reliable transfer to the device for consolidating the nonwoven provided according to the invention. When preparing a nonwoven fiber web having at least two fibers according to a preferred embodiment of the method of the present invention, it is preferred that, after laying down each nonwoven fiber web, pre-consolidation is performed using a pre-consolidation device or a hot fluid pre-consolidation device, which is suitably connected downstream of the associated fiber producing device or the associated spinning beam, in particular directly downstream thereof.

[0013] In the scope of the method according to the present invention, the at least one hot fluid pre-consolidation device or the hot air pre-consolidation device is configured as a hot air knife and / or a hot air field. But in principle, the pre-consolidation device can also be at least one roller or a leveling roller, especially a roller pair or a leveling roller pair. If the nonwoven is prepared with only one nonwoven web according to one embodiment, it is preferred that a hot air knife is used as a pre-consolidation device. If the nonwoven is prepared with a plurality of nonwoven webs or nonwoven plies according to a preferred embodiment, it is preferred that the hot air knife is used as a pre-consolidation device for the nonwoven web or nonwoven plies that are laid at the top or last, and especially the hot air knife and the hot air field are used as pre-consolidation devices for the remaining nonwoven webs or nonwoven plies. In the case mentioned later, it has been proved that the residence time of applying hot air exceeds 0.1s and is particularly effective.

[0014] It has proven to be particularly effective within the scope of the invention that at least one hot fluid main consolidation device or at least one hot air main consolidation device is designed as a hot air furnace, particularly preferably in the form of an omega furnace and / or a multi-drum furnace and / or a single belt furnace and / or a double belt furnace. Consolidation or main consolidation using the at least one hot fluid main consolidation device is preferably carried out by applying at least one hot fluid to one or both sides of the nonwoven in the at least one hot fluid main consolidation device.

[0015] Furthermore, it has proven particularly advantageous within the scope of the present invention that at least one hot fluid main consolidation device or at least one hot air main consolidation device is configured as a hot air furnace, particularly preferably in the form of a hot air field and / or a multi-drum furnace and / or a single-belt furnace and / or a double-belt furnace. According to one embodiment of the present invention, consolidation or main consolidation using at least one hot fluid main consolidation device is carried out by applying at least one hot fluid to the nonwoven on one side or both sides in at least one hot fluid main consolidation device, and in particular before being removed from the web laying device, wherein the nonwoven is preferably subsequently consolidated after being removed using at least one calender roller, in particular using at least one calender having a calender roller or a calender roller pair. Furthermore, within the scope of the invention, at least two hot fluid main consolidation devices are provided, wherein preferably a first consolidation or main consolidation of the nonwoven is carried out by means of a first hot fluid main consolidation device before the nonwoven is removed from the web laying device, and wherein preferably a second or further consolidation or main consolidation is carried out by means of a second hot fluid main consolidation device after the nonwoven is removed from the web laying device and particularly preferably after consolidation by means of at least one calender roller, in particular by means of at least one calender having a calender roller or a calender roller pair. In this embodiment, the at least one calender roller is therefore preferably arranged between the two hot fluid main consolidation devices in the conveying direction F of the nonwoven.

[0016] According to a particularly preferred embodiment of the method according to the present invention, the residence time of the nonwoven in the hot fluid main consolidation device is 0.4s to 25s, preferably 1s to 15s, and / or the fluid velocity of the fluid in the hot fluid main consolidation device is 0.4 to 3m / s, preferably 0.5 to 2m / s.

[0017] Within the scope of the present invention, the surface temperature T1 of the at least one calender roller, in particular the at least one calender or calender roller pair with the calender roller, is higher than the fluid temperature T2 of the at least one hot fluid main consolidation device, preferably by 0.5° C. to 10° C., preferably by 1° C. to 5° C., or lower than the fluid temperature T2 of the at least one hot fluid main consolidation device, or is identical or substantially identical to the fluid temperature T2 of the at least one hot fluid main consolidation device. Within the scope of the present invention, at least one calender roller, in particular at least one calender or calender roller pair with the calender roller, preferably refers to a heated calender roller or a heated calender. By the temperature relationship between the surface temperature of at least one calender roller or calender and the fluid temperature of at least one hot fluid main consolidation device, in particular in combination with the aforementioned residence time and / or fluid speed, a method can be provided, with which nonwovens characterized by an optimal compromise of their individual properties can be produced very flexibly, so that the aforementioned technical problems can be solved very flexibly, simply and reliably.

[0018] In principle, within the scope of the present invention, the fibers of at least one nonwoven web are made into staple fibers or at least one nonwoven web comprises staple fibers. According to a preferred embodiment, the fibers of at least one nonwoven web are made into continuous filaments. Particularly preferably, within the scope of the method according to the present invention, the fibers of all nonwoven webs are made into continuous filaments. Within the scope of the present invention, fiber refers in particular to continuous filaments. Continuous filaments are distinguished from staple fibers due to their almost unlimited length, and the staple fibers have significantly smaller lengths, for example 1mm to 60mm.

[0019] A particularly preferred embodiment of the method according to the present invention is characterized in that the fibers of the at least one nonwoven web are made or spun into continuous filaments. Preferably, the fibers of the at least one nonwoven web or at least one nonwoven web of the nonwoven are made into continuous filaments consisting of at least one thermoplastic, preferably at least one polyolefin. It is recommended that the at least one polyolefin is polypropylene and / or polyethylene. In principle, the continuous filaments can also be made of other thermoplastics, such as polyesters, such as polyethylene terephthalate (PET) and / or polylactic acid (PLA), and mixtures of the above-mentioned thermoplastics. According to one embodiment, a copolymer of the thermoplastic is used. Conventional additives, such as plasticizers, fillers, colorants, etc., can be metered into the thermoplastic. Within the scope of the present invention, the continuous filaments of the at least one nonwoven web or at least one nonwoven web of the nonwoven are made into spunbonded continuous filaments. In principle, the continuous filaments of the at least one nonwoven web or a nonwoven web of the nonwoven can also be made into meltblown continuous filaments.

[0020] According to a particularly preferred embodiment of the method according to the invention, the fibers of the at least one nonwoven web are made or spun into crimped continuous filaments, wherein the continuous filaments or crimped continuous filaments are particularly preferably made or spun into multicomponent filaments and very particularly preferably made or spun into bicomponent filaments.

[0021] In this connection, it has proven to be particularly advantageous that the multi-component filaments or bi-component filaments have a first component, preferably with a low melting point, which consists of or is essentially composed of at least one thermoplastic, in particular at least one polyolefin, preferably polyethylene and / or polypropylene, and / or the multi-component filaments or bi-component filaments have a second or other component, preferably with a higher melting point, which consists of or is essentially composed of at least one thermoplastic, in particular at least one polyester and / or polypropylene. The term "low-melting component, in particular a first low-melting component" in the context of the present invention refers in particular to a component of the multi-component filaments or bi-component filaments that has a lower melting temperature than a component of the multi-component filaments or bi-component filaments that has a higher melting point than the first component, in particular a second or other component with a higher melting point. In the context of the present invention, the low-melting component or the low-melting first component of the multi-component filaments or bi-component filaments is in particular a bonding component for the multi-component filaments or bi-component filaments.

[0022] In the context of the present invention, in particular polyethylene terephthalate (PET) and / or polylactic acid (PLA) are suitable as polyesters. According to one embodiment, copolymers of these plastics are used. If, here or hereinafter, reference is made to a component of a multicomponent filament or a bicomponent filament and in particular to a plastic or a polymer, "essentially consisting thereof" is mentioned, this means in particular that the component or the polymer is present in at least 95% by weight, preferably in at least 97% by weight, and preferably in at least 98% by weight. The remaining % by weight may in particular consist of additives such as plasticizers, fillers, colorants, etc.

[0023] According to a particularly preferred embodiment of the present invention, the first component of the multicomponent filaments or bicomponent filaments, preferably with a low melting point, is based on polyethylene and preferably consists of polyethylene or consists essentially of polyethylene. According to another preferred embodiment, the first component of the multicomponent filaments or bicomponent filaments, preferably with a low melting point, is based on polypropylene and preferably consists of polypropylene or consists essentially of polypropylene. Instead of polypropylene, or in addition to polypropylene, at least one polypropylene copolymer can also be used within the scope of the present invention.

[0024] According to a preferred embodiment of the present invention, the second or other components of multi-component filaments or bi-component filaments, in particular, with a higher melting point, are based on at least one polyester and / or are based on polypropylene. Particularly preferably, the second or other components of multi-component filaments or bi-component filaments, in particular, with a higher melting point, are composed of at least one polyester and / or polypropylene. For the second or other components, instead of polypropylene, or in addition to polypropylene, at least one polypropylene copolymer can also be used, and preferably, instead of polyester, or in addition to polyester, at least one polyester copolymer can also be used. Suitably, polyethylene terephthalate (PET) and / or polylactic acid (PLA) are particularly suitable as polyesters, and PET copolymers (Co-PET) are particularly suitable as polyester copolymers. Polylactic acid copolymers (Co-PLA) can also be used as the first component, in particular, with a low melting point, within the scope of the present invention, and polylactic acid (PLA) can be used as the second or other components, in particular, with a high melting point.

[0025] Within the scope of the method according to the invention, continuous filaments, preferably crimped continuous filaments, are produced or spun into multicomponent filaments or bicomponent filaments with a side-by-side configuration and / or with a sheath-core configuration, in particular with an eccentric sheath-core configuration, and preferably the first component, preferably with a low melting point, is the sheath component and the second component, preferably with a higher melting point, is the core component. If the continuous filaments are produced or spun into multicomponent filaments or bicomponent filaments with a sheath-core configuration, then within the scope of the invention, in principle, they can also have a central sheath-core configuration.

[0026] If the continuous filament or the curled continuous filament is made or spun into a multi-component filament or bi-component filament line with an eccentric sheath-core configuration according to a preferred embodiment, then within the scope of the present invention, the sheath of the filament and the core of the filament are both constructed as a circle when observed in the cross section of the filament. According to another preferred embodiment of the present invention, the multi-component filament or the bi-component filament is made or spun into a multi-component filament or bi-component filament with an eccentric sheath-core configuration, and the core of these filaments is constructed as a fan-shaped when observed in the cross section of the filament, and with respect to its circumference, it has an arc-shaped circumferential segment and a linear circumferential segment, so that a D-shaped core appears to be obtained when observed in the cross section of the filament.

[0027] If continuous filaments or curled continuous filaments are made or spun into multicomponent filaments or bicomponent filaments having at least one first component with a preferably low melting point as mentioned above and at least one second or other component with a preferably high melting point as mentioned above within the scope of the method according to the present invention, then in at least one nonwoven fiber web of the nonwoven, the proportion of the first component with a preferably low melting point of the multicomponent filaments or bicomponent filaments based on the components of the multicomponent filaments or bicomponent filaments is 10 to 90 weight %, preferably 20 to 70 weight %, preferably 30 to 50 weight %.

[0028] The fiber structure of the non-woven fabric is a design of multi-component filaments or bi-component filaments, in particular having a first component with a preferably low melting point and a second or other component with a preferably high melting point, and the preferred design of multi-component filaments or bi-component filaments having a side-by-side configuration and / or a sheath-core configuration, preferably an eccentric sheath-core configuration, is based on the following recognition, that the non-woven properties can be adjusted very flexibly through these components or configurations of the filaments, and in particular in combination with the consolidation using at least one calendering roller and using at least one hot fluid main consolidation device arranged according to the present invention, a non-woven can be prepared, using which a particularly advantageous compromise of non-woven properties can be achieved to solve the technical problems of the present invention.

[0029] Associated therewith, it has proven particularly advantageous that the surface temperature T1 of the at least one calender roll, in particular of the at least one calender or calender roll pair having the calender roll, and / or the fluid temperature T2 of the at least one main consolidation device for the hot fluid satisfy the following conditions with respect to the melting temperature Tm of the preferably low-melting first component of the multicomponent filament or bicomponent filament: (Tm - 15 °C) < T1 and / or T2 < (Tm + 15 °C), preferably (Tm - 10 °C) < T1 and / or T2 < (Tm + 10 °C), preferably (Tm - 8 °C) < T1 and / or T2 < (Tm + 8 °C), particularly preferably (Tm - 7 °C) < T1 and / or T2 < (Tm + 7 °C), very particularly preferably (Tm - 6 °C) < T1 and / or T2 < (Tm + 6 °C), for example (Tm - 5 °C) < T1 and / or T2 < (Tm + 5 °C). In the context of the method according to the invention, the melting temperature Tm of the preferably low-melting first component is determined in particular by means of dynamic differential scanning calorimetry (DSC) in accordance with the ISO 11357-3:2011 standard. Thus, preferably, the surface temperature T1 of the at least one calender roll and / or the fluid temperature T2 of the at least one main consolidation device for the hot fluid satisfy the conditions set out above. Here, the surface temperature T1 preferably has the above relationship with the fluid temperature T2, such that T1 can preferably be higher than T2 or can be lower than T2 or equal to T2. If the main consolidation device for the hot fluid, in particular the hot air main consolidation device according to the preferred embodiment, is a hot air furnace, then in addition the fluid temperature in the context of the present invention corresponds in particular to the hot air temperature during hot air consolidation in the hot air furnace.

[0030] According to a very preferred embodiment of the method of the present invention, by means of the at least one calender roller, an embossed pattern consisting of a plurality of preferably non-interconnected embossing portions is introduced into the nonwoven. Within the scope of the present invention, the calender roller is a part of a calender, and the calender has at least one calender roller pair according to a particularly preferred embodiment, and at least one calender roller of the calender or calender roller pair, in particular one of two calender rollers, is preferably a calender roller for introducing the embossed pattern consisting of a plurality of embossing portions into the nonwoven. For this reason, the calender roller preferably has a complementary embossed pattern consisting of embossing elements. This will be further explained in detail below. Another or additional roller of the calender or calender roller pair is suitably a smoothing roller with a smooth outer surface. Therefore, within the scope of the method of the present invention, preferably a calender is utilized to consolidate the nonwoven, and the calender has at least one calender roller for introducing the embossed pattern formed by a plurality of embossing portions into the nonwoven, and also preferably has at least one smoothing roller. Then, the embossed pattern is preferably introduced into the nonwoven only from one side of the nonwoven. Nevertheless, the embossed pattern is preferably present on both nonwoven sides in the resulting nonwoven, wherein the embossing depth is particularly distributed differently on the two nonwoven sides. Within the scope of the present invention, when using a calender consisting of at least one calender roller pair, wherein one of the calender rollers has an embossing element for introducing an embossed pattern formed by a plurality of embossing portions into the nonwoven and a calender roller is designed as a smoothing roller, the two calender rollers have surface temperatures different from each other for consolidating the nonwoven. It is preferred that the calender roller with the embossing element has a higher surface temperature. In the case of different temperatures of the calender rollers, the above-mentioned surface temperature T1 particularly refers to the temperature of the calender roller with the embossing element.

[0031] In the context of the present invention, the term "embossed portion" refers in particular to a compacted location of the nonwoven at which the nonwoven has a smaller thickness than its non-embossed areas and at which the fibers of the nonwoven are at least partially connected or fused to one another, preferably by the action of pressure and / or temperature. According to a particularly preferred embodiment of the method according to the invention, the embossed portions each have a thickness of 0.05 to 0.6 mm. 2 , preferably 0.06 to 0.4 mm 2 , preferably 0.07 to 0.25 mm 2 , particularly preferably 0.08 to 0.15 mm 2 , and very particularly preferably 0.09 to 0.12 mm 2 Within the scope of the present invention, the embossing portions have a thickness of less than 0.3 mm. 2 , preferably less than 0.2mm 2 , preferably less than 0.18mm 2 , particularly preferably less than 0.15 mm 2, very particularly preferably less than 0.12 mm 2 , for example, less than 0.1 mm 2 These embodiments are based on the recognition that the embossed pattern formed by such a specially designed embossing portion and in particular by a relatively small embossing surface can at least significantly reduce the visual perceptibility of the embossed pattern to the human eye, thereby almost completely avoiding impairment of the visual properties of the resulting nonwoven.

[0032] In the scope of the present invention, the term "embossing pattern" refers in particular to a pattern obtained by a plurality of embossing portions of a nonwoven. The embossing pattern can be a regular and / or irregular embossing pattern. Preferably, the embossing pattern is a regular embossing pattern. Then, each embossing portion is preferably distributed on the obtained nonwoven at regular intervals, preferably at the same intervals. Further preferably, the embossing surface of each embossing portion of the embossing pattern is the same or substantially the same. It has been proven to be advantageous that the geometry of the embossing surface of each embossing portion is also the same or substantially the same. Very particularly preferably, the embossing pattern has the same or same size embossing portion or substantially the same or same size embossing portion, wherein the embossing portions with the same geometry or substantially the same geometry are uniformly distributed. But in principle it is also possible that each embossing portion of the embossing pattern has sizes and / or geometries that are different from each other, and / or the embossing portion is arranged on the nonwoven with an irregular embossing pattern. Furthermore, within the scope of the present invention, the geometry of the embossing means in particular the geometry of the embossing surface of the embossing in a plan view.

[0033] The embossing surface of the embossing part refers in particular to the embossed surface of the embossing part within the scope of the present invention, wherein when determining the size of the embossing surface, the material protrusions or material flanges that may be formed during the pressing or embossing process and at least partially surround the embossing part are in particular not part of the embossing surface of the embossing part. In the case where the embossing part or the embossing surface has a point-shaped or circular geometry in a top view, the embossing area of ​​the embossing part corresponds, for example, to the area of ​​the point-shaped or circular embossing part, wherein the material protrusions or material flanges that may surround the embossing part are not included in the embossing area of ​​the embossing part. The embossing part of the nonwoven according to the present invention respectively has an embossing surface within the above range, which means in particular that at least 95%, preferably at least 97%, of all embossing parts of the nonwoven have an embossing area within the above range. Particularly preferably, all embossing parts of the nonwoven have an embossing surface within the range. Within the scope of the present invention, the embossing surface of the embossing part can be determined in particular by an incident light or transmitted light 2D microscope, and / or by a scanning electron microscope (REM) and / or by micro-computed tomography (μCT). In a corresponding image evaluation, the embossing surface geometry or a geometry corresponding or substantially corresponding thereto is preferably used as the basis, and the evaluation is based on the respective optically imaged embossing surface in the embossing.

[0034] In the scope of the method according to the present invention, the embossed pattern is manufactured with the following specifications, that is, the minimum spacing d of the two embossed portions of the embossed pattern is respectively 0.6 to 3.0 mm, preferably 0.8 to 2.5 mm, preferably 0.9 to 2.0 mm, particularly preferably 0.95 to 1.8 mm and very particularly preferably 1.0 to 1.5 mm. Suitably, the minimum spacing d of the two embossed portions of the embossed pattern is respectively at least 0.6 mm, especially at least 0.8 mm, preferably at least 1.0 mm, particularly preferably at least 1.4 mm and fully particularly preferably at least 2.0 mm. The minimum spacing d of the two embossed portions of the embossed pattern refers in particular to the minimum spacing d of the two directly adjacent embossed portions of the embossed pattern, that is, the minimum spacing of an embossed portion of the embossed pattern to the embossed portion closest to it. In addition, the minimum spacing d of the two embossed portions of the embossed pattern particularly relates to the minimum spacing between the embossed boundaries of the two embossed portions, that is, the minimum spacing of the two embossed portions along the non-embossed surface of the non-woven fabric located therebetween. This embodiment is particularly based on the recognition that the visual perceptibility of the embossed pattern from the embossed portion can be further reduced. The above-mentioned minimum spacing between two embossed portions of the embossed pattern is preferably at least 95%, preferably at least 97% of all embossed portions of the nonwoven. Particularly preferably, the above-mentioned minimum spacing between two embossed portions relates to all embossed portions of the nonwoven.

[0035] Another preferred embodiment of the method according to the present invention is characterized in that the embossed pattern is manufactured with the following specifications, that is, the total embossed area of ​​the embossed pattern accounts for the total surface area of ​​the nonwoven fabric in a ratio of 2 to 15%, preferably 2.5 to 12%, preferably 3 to 8%, particularly preferably 3.5 to 6% and very particularly preferably 3.8 to 5.2%. Within the scope of the present invention, the embossed pattern is produced according to the following conditions, that is, the total embossed surface of the embossed pattern accounts for the total surface of the nonwoven fabric in a ratio of less than 10%, preferably less than 8%, preferably less than 6.5%, particularly preferably less than 5.5%, and very particularly preferably less than 5%. The visual perceptibility of the embossed pattern from the embossed portion can be further reduced by the total embossed area of ​​the embossed pattern accounting for the total surface area of ​​the nonwoven fabric. The total embossed area of ​​the embossed pattern in this context especially refers to the sum of all embossed surfaces of the embossed pattern. The total surface area of ​​the nonwoven fabric especially refers to the surface area of ​​all nonwoven fabrics including the embossed and non-embossed regions within the scope of the present invention.

[0036] Within the scope of the method according to the invention, the calender line load of the calender roll or calender is 4 N / mm to 60 N / mm, preferably 10 N / mm to 40 N / mm, particularly preferably 15 N / mm to 35 N / mm, very particularly preferably 20 N / mm to 30 N / mm. Further preferably, the calender line load is 2 to 20 N / mm, preferably 3 to 15 N / mm, preferably 4 to 8 N / mm, per percentage of the total embossed area of ​​the above-mentioned embossed pattern to the total surface area of ​​the nonwoven.

[0037] It is particularly preferred within the scope of the method according to the invention to prepare a nonwoven having at least two nonwoven fiber webs made of fibers, wherein for this purpose first fibers are produced by at least one first fiber generating device, in particular at least one first spinning beam, and the first fibers are subsequently laid on a laying device, in particular a laying screen belt, to form a nonwoven fiber web, wherein second fibers are produced by at least one second fiber generating device, in particular at least one second spinning beam, and the second fibers are subsequently laid on the first nonwoven fiber web to form a second nonwoven fiber web, and wherein the aggregate or nonwoven consisting of at least two nonwoven fiber webs is consolidated by means of at least one calender roller, in particular by means of at least one calender having a calender roller or a calender roller pair, and wherein the nonwoven is also consolidated or mainly consolidated by means of at least one hot fluid main consolidation device, in particular by means of at least one hot air main consolidation device. As mentioned above, within the scope of such an embodiment, at least one pre-consolidation device, preferably at least one hot fluid pre-consolidation device, preferably at least one hot air pre-consolidation device is appropriately connected downstream of each fiber producing device or each spinning beam, in particular directly downstream thereof, and the laid non-woven fiber web is preferably pre-consolidated with the corresponding pre-consolidation device before the consolidation or main consolidation of the non-woven.

[0038] If the nonwoven with at least two nonwoven webs consisting of fibers is prepared within the scope of the method according to the invention, it is particularly preferred that the fibers are made into continuous filaments, particularly crimped continuous filaments and are laid as spunbonded nonwoven webs respectively. The performance of the fibers or continuous filaments of the different nonwoven webs or nonwoven plies of the nonwoven obtained may be different at this. For example, the continuous filaments of the first nonwoven web produced with the first spinning manifold can have an average fineness smaller than the continuous filaments of the second nonwoven web produced with the second spinning manifold, so that it can be said that a fineness gradient is produced. It has been proved to be advantageous that at least one nonwoven web or nonwoven ply fiber assigned to the outer surface of the nonwoven is made into crimped continuous filaments and / or staple fibers. Thus, the softness of the nonwoven can be improved and the bending stiffness can be reduced.

[0039] In order to solve this technical problem, the present invention also teaches a device for preparing a nonwoven having at least one nonwoven fiber web made of fibers, in particular for implementing the aforementioned method, wherein the device has at least one fiber producing device, in particular at least one spinning beam and at least one laying device, in particular at least one laying screen belt, for laying the fibers into a nonwoven fiber web, wherein at least one calendering roller, in particular a calendering machine having the calendering roller or a calendering roller pair having the calendering roller, is provided for consolidating the nonwoven, and wherein there is also at least one hot fluid main consolidation device, in particular at least one hot air main consolidation device, for consolidating or main consolidating the nonwoven.

[0040] Within the scope of the present invention, the device has at least one pre-consolidation device, preferably connected downstream of the at least one fiber producing device or the at least one spinning beam, in particular directly connected downstream thereof, preferably with at least one hot fluid pre-consolidation device, preferably at least one hot air pre-consolidation device, for pre-consolidating the non-woven, and wherein the at least one hot fluid pre-consolidation device or the at least one hot air pre-consolidation device is particularly preferably constructed in the form of a hot air knife and / or a hot air field.

[0041] The mesh-laying screen belt of the device according to the present invention is suitably a mesh-laying screen belt that is continuously encircled. Within the scope of the present invention, the at least one fiber-generating device or the at least one spinning manifold is configured to produce a spunbonded nonwoven web from continuous filaments, especially from crimped continuous filaments. If the nonwoven is configured as a nonwoven laminate composed of at least two nonwoven webs or nonwoven plies according to one embodiment of the present invention, then within the scope of the present invention, there are at least two fiber-generating devices, especially at least two spinning manifolds, and preferably all fiber-generating devices or spinning manifolds are designed to produce a spunbonded nonwoven web composed of continuous filaments, especially from crimped continuous filaments. Very particularly preferably, at least one fiber-generating device or at least one spinning manifold, preferably all fiber-generating devices or all spinning manifolds of the device according to the present invention are arranged to produce multi-component filaments or bi-component filaments. In addition, within the scope of the present invention, the device is configured to prepare at least one nonwoven web from crimped continuous filaments. Preferably, at least one fiber-generating device or at least one spinning manifold is arranged to produce crimped continuous filaments. When a plurality of spinning beams are used for the apparatus according to the invention, at least one spinning beam or at least two spinning beams or all spinning beams are arranged to produce crimped continuous filaments.

[0042] A very suitable design of the present invention is characterized in that at least one cooling device for cooling the fibers or continuous filaments spun by means of at least one fiber generating device or by means of at least one spinning manifold and at least one stretching device connected to the cooling device for stretching the fibers or filaments are provided. Advantageously, at least one diffuser is connected to the stretching device along the flow direction of the fibers or filaments. A very recommended embodiment of the present invention is characterized in that the unit consisting of the cooling device and the stretching device is constructed as a closed unit and no other air is supplied to the unit from the outside except for the cooling air supplied to the cooling device. Advantageously, the fibers or filaments leaving the diffuser are laid directly on the laying device or the laying screen belt.

[0043] According to a preferred embodiment of the device according to the invention, at least one calender roller, in particular a calender having said calender roller or said calender roller pair is arranged before or after at least one hot fluid main consolidation device in the conveying direction F of the nonwoven. According to a preferred embodiment, at least one hot fluid main consolidation device is arranged before the calender roller in the conveying direction F of the nonwoven, in particular before the calender having said calender roller. According to a particularly preferred embodiment, at least one hot fluid main consolidation device is arranged after the calender roller in the conveying direction F of the nonwoven, in particular after the calender having said calender roller.

[0044] According to another preferred embodiment of the device according to the invention, at least one calender roller has a complementary embossed pattern consisting of embossing elements for introducing an embossed pattern consisting of a plurality of embossed portions into the nonwoven. With such a calender roller having a complementary embossed pattern consisting of embossed elements, the aforementioned embossed pattern formed by the embossed portions can be introduced into the nonwoven. Suitably, in addition to the calender roller for introducing the embossed pattern consisting of the embossed portions into the nonwoven, the calender or calender roller pair also has a second or further calender roller, which is configured as a smoothing roller with a smooth outer surface.

[0045] It has proven to be particularly advantageous if the embossing elements of the complementary embossing pattern of the calender roller each have a diameter of 0.05 to 0.6 mm. 2 , preferably 0.06 to 0.4 mm 2 , further preferably 0.07 to 0.25 mm 2 , particularly preferably 0.08 to 0.15 mm 2 , very particularly preferably 0.09 to 0.12 mm 2The pressing surface of the embossing element of the calender roller is, within the scope of the present invention, particularly a surface provided for producing an embossing surface of the embossing portion. If the embossing element of the calender roller is, for example, constructed as a cylindrical embossing element for producing an embossing surface having a dot-shaped or circular geometry in a top view, the pressing surface of the embossing element particularly corresponds to the surface on the upper side of the cylinder. If the embossing element of the calender roller is constructed with a dot-shaped or circular geometry in a top view, for example a truncated cone shape, i.e., with a side angle, in order to produce the embossing surface, the pressing surface of the embossing element particularly corresponds to the top surface of the truncated cone. One embodiment of the present invention uses a plurality of side angles for the embossing element, wherein the embossing element preferably has a smaller side angle in the area provided for contact with the nonwoven than further in the direction of the bottom of the calender roller. The side angle gradient can be step-by-step or continuous here. Within the scope of the invention, the calender roller for introducing an embossing pattern formed by embossing elements into the nonwoven is designed in particular with regard to its complementary embossing pattern or with regard to the arrangement and design of the embossing elements so that an embossing pattern with the above-mentioned parameters or properties can be achieved in the nonwoven.

[0046] In the context of the invention, the embossing elements of the complementary embossing pattern of at least one calender roller each have an embossing height in the range of 0.3 to 1.2 mm, preferably 0.4 to 0.9 mm, particularly preferably 0.5 to 0.8 mm. The embossing height here refers in particular to the height difference between the pressing surface of the embossing element and the bottom of the calender roller. This embodiment is based on the recognition that compaction of the nonwoven can be substantially minimized during calendering with such a calender roller.

[0047] In order to solve the technical problem, the present invention also teaches a nonwoven fabric, which is prepared according to the above method and / or using the above device.

[0048] According to a particularly preferred embodiment of the nonwoven according to the invention, the nonwoven has an embossing pattern consisting of a plurality of embossing portions which are preferably not connected to one another, wherein the embossing portions preferably each have a diameter of 0.05 to 0.6 mm. 2 , preferably 0.06 to 0.4 mm 2 , further preferably 0.07 to 0.25 mm 2 , particularly preferably 0.08 to 0.15 mm 2 , very particularly preferably 0.09 to 0.12 mm 2, and / or wherein the embossing surface of the embossing portion preferably has at least one geometric shape selected from the following group in a top view: "point-shaped or circular, elliptical, square, rectangular, rhombus, polygonal, linear, wavy". Preferably, the embossing surfaces or embossing portions of the embossing pattern have the same or essentially the same geometric shapes, respectively. However, it is also within the scope of the present invention in principle that the embossing pattern has embossing surfaces or embossing portions with different geometric shapes. A very particularly preferred embodiment of the present invention is characterized in that the embossing portion or the embossing surface of all embossing portions is point-shaped or circular in a top view. Furthermore, the geometric shape of the embossing portion within the scope of the present invention refers in particular to the geometric shape of the embossing surface of the embossing portion in a top view.

[0049] A preferred embodiment of the nonwoven fabric of the present invention is characterized in that the aspect ratio of the embossing surface of the embossing portion is respectively less than 4, preferably less than 3, particularly preferably less than 2, for example equal to 1. In this regard, the aspect ratio of the embossing surface refers in particular to the ratio of the maximum length or length extension of the embossing surface of the embossing portion to the maximum width or width extension of the embossing surface of the embossing portion, and for example refers to the ratio of the length of the axis of symmetry. When the embossing surface of the embossing portion is a dot-shaped or circular geometry in a top view, the aspect ratio is, for example, equal to 1. When the embossing surface of the embossing portion is an elliptical geometry in a top view, the aspect ratio corresponds, for example, to the ratio of the length of the major axis or major semi-axis of the ellipse to the length of the minor axis or minor semi-axis. When the embossing surface of the embossing portion is a rectangular geometry in a top view, the aspect ratio corresponds, for example, to the ratio of the length of the rectangle to the width of the rectangle. When the embossing surface of the embossing portion is a rhombus geometry in a top view, the aspect ratio corresponds, for example, to the ratio of the length of the longer diagonal of the rhombus to the length of the shorter diagonal. When the embossing surface of the embossing portion has a square geometric shape in a top view, the aspect ratio is equal to 1. If it is a curve, the aspect ratio of the embossing surface is preferably described by the aspect ratio of the surrounding rectangle.

[0050] Preferably, the nonwoven has a weight of less than 200 g / m 2 , especially less than 150g / m 2 , preferably less than 100g / m 2 , preferably less than 75g / m 2 , particularly preferably less than 50g / m 2 and very particularly preferably less than 30 g / m 2 The nonwoven has a weight per unit area of ​​10 g / m2, and / or the nonwoven has a thickness of 0.1 to 1.0 mm, preferably 0.15 to 0.8 mm, preferably 0.2 to 0.65 mm, particularly preferably 0.25 to 0.55 mm. Very particularly preferably, the nonwoven has a weight per unit area of ​​10 g / m2. 2 Up to 80g / m 2 , preferably 15g / m 2 Up to 60g / m2 , preferably 15g / m 2 Up to 30g / m 2 It is also within the scope of the invention that the nonwoven has a thickness h of at least 0.3 mm, in particular at least 0.45 mm, preferably at least 0.55 mm, preferably at least 0.6 mm, particularly preferably at least 0.625 mm. The thickness h here refers in particular to the maximum thickness or the total thickness of the nonwoven transversely, in particular perpendicularly or substantially perpendicularly to its planar extension in the non-embossed area of ​​the nonwoven. The thickness or the total thickness h of the nonwoven is measured in accordance with method WRT 120.6 (05), option A.

[0051] In the scope of the present invention, the nonwoven has a wear resistance according to at least 2 levels of the Martindale standard, preferably a wear resistance according to 1 level of the Martindale standard, and / or the nonwoven has a maximum bending stiffness of a cantilever of 100 mm, preferably a maximum of 90 mm, preferably a maximum of 80 mm, particularly preferably a maximum of 70 mm and very particularly preferably a maximum of 65 mm. This embodiment is based on the following recognition that the nonwoven is therefore characterized by a very satisfactory wear resistance, and / or the nonwoven has an advantageously low bending stiffness, and in particular also has an improved drapability compared to known measures or nonwovens. This advantageously contributes to solving the technical problem and in particular contributes to the balance of the best nonwoven properties. The wear resistance of the nonwoven is determined in particular by the Martindale abrasion test device according to the following test method within the scope of the present invention:

[0052] In particular, the device "SDL Atlas M235 Martindale Tester" is used as the test device. The procedure for determining the wear resistance is preferably based on WSP20.5 (05), wherein in particular the following deviations from WSP20.5 (05) are made: the surfaces (top / bottom) are tested individually; at least 10, preferably at least 20 tests are carried out for each sample and surface, wherein the test pieces are taken uniformly from the sample surface, and the final result is the arithmetic mean. The test specimen should be taken from a representative position, i.e. not just from the edge, for example, because the test or result deviation should not be affected by macroscopic deviations (such as poor process control), but only by typical (local) fluctuations; the sample to be tested is tensioned on a standard felt and mounted in the lower fixture; the same nonwoven is used as the moving upper friction surface, the test surfaces are pressed against each other, and this nonwoven is fixed together with a PU foam block (e.g. a foam block of SDL Atlas); the contact pressure is 9 kPa; 32 cycles, i.e. two complete cycles of Lissajous figures; the pairing (test specimen and upper friction surface) is replaced after each test;

[0053] The samples are rated on a scale of 1 to 5, with 1 being the highest score. For example, if the average value for the top surface is 1 and the average value for the bottom surface is 3, the sample is rated 1 overall. Only changes in the nonwoven are evaluated, and if the nonwoven has previously had similar defects, this is disregarded. In this context, for example, a fiber strand means a group or bundle of fibers on the surface. If a test specimen clearly has such a defect from the outset, the test specimen in question must be excluded.

[0054] 1 point: Almost no change can be observed from above. Slight looseness of the surface is allowed, in which only the filaments are allowed to loosen, but no larger or longer clumps are allowed. When observed from the side, the height of the loose filaments should not exceed 5mm. Single filaments or multiple filaments are allowed to gather into small balls with a diameter of less than 2mm.

[0055] 2 points: In addition to the above damage mode (1 point): the filaments are loose and entangled with adjacent filaments to form elongated agglomerates. These filament groups are called "strands" or "lines or bundles". These strands are 5 to 40 mm long and are connected to the substrate at least every 10 mm of length. The maximum height of a strand is 5 mm (5 mm above the surface) and the maximum width is 2 mm.

[0056] 3 points: The "strands" are no longer connected to the substrate along their length, the possible connections are >10 mm above and below each other, or the strands are only connected to the sample at the start and end points. It is possible to lift and move these strands, for example with a needle.

[0057] 4 points: The strands connect to adjacent strands to form a web. A "spider web."

[0058] 5 points: The sample is further damaged and holes are formed for the first time.

[0059] The flexural stiffness of a nonwoven is determined within the scope of the present invention, in particular, in accordance with the method “WSP 90.1 (05) Standard Test Method for Stiffness of Nonwoven Fabrics Using Cantilever Test”.

[0060] In the context of the present invention, the strength of the nonwoven in the machine direction (MD direction) is at least 8 N / 5 cm, in particular at least 10 N / 5 cm, preferably at least 15 N / 5 cm, preferably at least 17.5 N / 5 cm, particularly preferably at least 20 N / 5 cm, very particularly preferably at least 22.5 N / 5 cm. In the context of the present invention, the machine direction (MD direction) is in particular the conveying direction F of the nonwoven on the laying device. In the context of the present invention, the strength of the nonwoven in the machine direction is determined in particular according to the following method: "Determination of tensile strength (based on Edana 20.2-89)": unit N / 5 cm; sample width 50 mm; tension length 100 mm; test speed 200 mm / min.

[0061] According to a preferred embodiment of the invention, the nonwoven is constructed in the form of a nonwoven laminate consisting of at least two nonwoven fiber webs or nonwoven plies.

[0062] The invention is based on the recognition that a nonwoven can be provided by the method according to the invention, which is characterized by an optimal balance between favorable mechanical properties, sufficient thickness or bulk, low rigidity or good drapability and favorable wear resistance. An optimal balance of these properties can be achieved by the consolidation according to the invention using at least one calender roller, in particular by the combination of at least one calender or calender roller pair with calender rollers and at least one hot fluid main consolidation device. It should be emphasized that within the scope of the method according to the invention, these nonwoven properties can be achieved very functionally reliable and can nevertheless be achieved with relatively simple measures. In addition, the method according to the invention is characterized by its optimal flexibility. According to a preferred embodiment, the nonwoven properties can be further optimized by the temperature relationship between the calender roller or calender and the hot fluid main consolidation device, as well as by the composition of the fibers or filaments and by the configuration of the fibers or filaments. If according to a preferred embodiment, the embossed pattern consisting of a plurality of embossing parts and according to a particularly preferred embodiment, the embossed pattern consisting of a plurality of embossing parts with a relatively small embossing area is introduced into the nonwoven, then the damage to the visual characteristics of the nonwoven obtained can also be almost completely avoided, at this, despite the above, the nonwoven still has the favorable mechanical properties obtained by such a calendering process or an embossing process. In a word, it can be determined that the optimal balance of the aforementioned each nonwoven characteristic can be achieved within the scope of the present invention. Through the flexibility of the method, for example, in terms of the temperature for the consolidation step or in terms of the design of the fiber or the long filament, the nonwoven characteristic can be further optimized according to the preferred embodiment of the method of the invention. DETAILED DESCRIPTION

[0063] The present invention is further described below with the aid of embodiments:

[0064] In the following three exemplary embodiments, in particular only the consolidation or main consolidation of the nonwoven is differentiated, wherein the following parameters and embodiments apply primarily to all three exemplary embodiments (Examples 1 to 3):

[0065] This is a spunbond nonwoven consisting of two spunbond nonwoven webs or spunbond nonwoven layers, which are spun using a first spinning beam and a second spinning beam. The resulting nonwoven has a unit weight of 20 g / m 2. The laying screen belt speed is 315 m / min. The fibers are made or laid as crimped continuous filaments in the form of bicomponent filaments, respectively, wherein the filaments of the first spinning manifold have an eccentric sheath-core configuration with a D-shaped core, and the filaments of the second spinning manifold have a side-by-side configuration. Polyethylene (DOW Aspun 6850+2 wt. % white coloring additive) is used as the first component of the filaments of the first spinning manifold. Polypropylene (Exxon PP3155+5 wt. % Borealis HL712FB+1 wt. % lubricant) is used as the second component of the filaments of the second spinning manifold. The mass ratio of the first component to the second component is 50:50. Polyethylene (DOW Aspun 6834+2 wt. % white coloring additive) is used as the first component of the filaments of the second spinning manifold. Polypropylene (Exxon PP 3155+1 wt. % Borealis HL712FB+1 wt. % lubricant) is used as the second component of the filaments of the second spinning manifold. The mass ratio of the first component to the second component is 40:60. The capacity of the first tank is 145 kg / h / m, and the capacity of the second tank is 180 kg / h / m.

[0066] After the first box, use a hot air knife (650m 3 / h / m; 145°C, 90mm structure length) for pre-consolidation, and hot air field (1.5m / s, 135°C, 900mm structure length) for pre-consolidation. After the second box, hot air knife (625m 3 / h / m; 145 ° C, 90 mm structure length) for pre-consolidation and consolidation or main consolidation with a hot air field with three different temperature zones in succession (the structure length of each temperature zone is 1200 mm), which are operated at different temperatures in different embodiments, as described below. Consolidation is then carried out using a calender as given. The average fineness of the filaments of the first nonwoven fiber web or nonwoven layer is 1.3 denier. The average fineness of the filaments of the second nonwoven fiber web or nonwoven layer is 2.0 denier.

[0067] For the consolidation or main consolidation of the nonwovens of the examples (Examples 1 to 3), the following common conditions and embodiments apply: The total pressing surface of the embossing elements of the calender is 4%, i.e. 41.7 Fig / cm 2 , and the embossing element has a circular pressing surface; the diameter of the pressing surface of the embossing element is 0.35 mm, and thus has a diameter of approximately 0.096 mm 2The pressing area is 1.2 mm; the spacing of the embossing elements is determined by analogy with the minimum spacing d of the two embossing parts mentioned above; the calender comprises an upper calender roller with an embossing element and a lower calender roller with a smooth surface. A hot air main consolidation device in the form of an Ω furnace is arranged behind the calender in the conveying direction F of the nonwoven, with a diameter of 1414 mm and an effective flow length of 3500 mm (air speed: 0.8 m / s). The cantilever values ​​and Martindale values ​​given below are measured as described above; in the Martindale data, "above" is attributed to the side of the calender roller with the embossing element, and "below" is attributed to the side of the laying screen belt.

[0068] Embodiment 1:

[0069] After the second spinning beam, consolidation or main consolidation is carried out using a hot air field, with three different temperature zones in succession: 120°C / 130°C / 80°C; calender surface temperature: 129°C for the calender roll with embossing element and 123°C for the smoothing roll; calender line load: 30N / mm; Ω furnace temperature: 80°C.

[0070] A nonwoven was obtained with a strength of 20.7 N / 5 cm in the machine direction (MD direction), a thickness of 0.45 mm, an overhang of 65 mm, and an abrasion resistance of Martindale 1 (upper) / 1 (lower). Thus, in particular, a product with very favorable abrasion resistance, very favorable low overhang values, sufficient strength, and satisfactory thickness was obtained.

[0071] Embodiment 2:

[0072] After the second spinning beam, consolidation or main consolidation is carried out using a hot air field, with three different temperature zones in succession: 120°C / 130°C / 130°C; calender surface temperature: 121°C for the calender roll with embossing element and 127°C for the smoothing roll; calender line load: 30 N / mm; Ω furnace temperature: 128°C.

[0073] A nonwoven was obtained with a strength of 26.6 N / 5 cm in the machine direction (MD direction), a thickness of 0.39 mm, an overhang of 77 mm, and an abrasion resistance of Martindale 1 (upper) / 1 (lower). Thus, a product having particularly favorable abrasion resistance, favorable low overhang values, very favorable strength, and sufficient thickness was obtained.

[0074] Embodiment 3 (prior art or not the present invention):

[0075] After the second spinning beam, consolidation or main consolidation is carried out using a hot air field, with three different temperature zones in succession: 120°C / 130°C / 130°C; calender: open, i.e. without contact with the nonwoven or consolidation using a calender; Ω furnace temperature: 138°C; therefore, no combined consolidation using a calender is used.

[0076] A nonwoven was obtained with a strength of 21.3 N / 5 cm in the machine direction (MD direction), a thickness of 0.53 mm, a cantilever of 105 mm, and an abrasion resistance of Martindale 2.5 (upper) / 1 (lower). Thus, a product with unfavorable abrasion resistance, unfavorable cantilever values, sufficient strength, and favorable thickness was obtained, in particular, on one side of the nonwoven.

[0077] The invention is explained in more detail below with reference to the drawing, which shows only one exemplary embodiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] In the schematic:

[0079] Figure 1 shows a vertical section through a device according to the invention,

[0080] Figure 2 Shown through Figure 1 A vertical cross-sectional view of a portion of a device,

[0081] Figure 3 A top view of a nonwoven according to the invention is shown,

[0082] Figure 4 Shown along Figure 1 Cross-section along line AA.

[0083] Figure 1 The apparatus 14 according to the invention is shown for carrying out the method according to the invention and for producing a nonwoven 1, which has two nonwoven webs 2, 2' consisting of crimped continuous filaments 10. The apparatus preferably and in this embodiment has two spinning beams 3, 3', which are preferably and in this embodiment are arranged to produce spunbond nonwoven webs 2, 2', respectively, which are composed of crimped continuous filaments 10 in the form of bicomponent filaments. In addition, according to the preferred embodiment, there is a continuously circulating laying screen belt 4 for laying the continuous filaments 10 into nonwoven webs 2, 2'. The apparatus 14 preferably and in this embodiment has a calender roller 5 for embossing a plurality of embossing portions 12 that are not connected to each other. Figure 3 and 4) is introduced into the nonwoven 1. The calender roller 5 is preferably and in this embodiment part of a calender 6 consisting of a calender roller pair 5, 7. Preferably and in this embodiment, the calender roller 5 of the calender 6 has a complementary embossing pattern 15 consisting of embossing elements 16, which preferably each have a diameter of 0.05 to 0.6 mm. 2 The pressing surface 17 is hereby understood to be in particular the surface of the embossing element 16 of the calender roller 5 which is provided for producing the embossing surface 13 of the embossed portion 12 of the nonwoven 1. Figure 1 In the embodiment of the present invention, the embossing element 16 of the calender roller 5 is configured as a truncated cone, and the pressing surface 17 corresponds to the top surface of the truncated cone. The other or further calender rollers 7 of the calender 6 are preferably and in this embodiment configured as smoothing rollers 7 with a smooth outer surface.

[0084] According to a particularly preferred embodiment and according to Figure 1 In the embodiment of the present invention, the device 14 has a hot air main consolidation device 8, which is preferably arranged after the calender roller 5 or after the calender 6 in the conveying direction F of the nonwoven. Preferably and in the present embodiment, the hot air main consolidation device 8 is configured as a hot air furnace. Suitably and in this embodiment, the device 14 also has two pre-consolidation devices in the form of hot air pre-consolidation devices 9, 9'. The hot air pre-consolidation devices 9, 9' are preferably and in this embodiment respectively arranged before the calender roller 5 or before the calender 6 in the conveying direction F of the nonwoven 1. Preferably and according to Figure 1 In the embodiment of the present invention, the hot air pre-consolidation devices 9, 9' are directly connected to the downstream of the spinning beams 3, 3' for pre-consolidating the laid nonwoven fiber webs 2, 2'. The first hot air pre-consolidation device 9 is preferably directly connected to the downstream of the first spinning beam 3 in the conveying direction F of the nonwoven 1, followed by the second spinning beam 3', and the second hot air pre-consolidation device 9' is directly connected to the downstream of the second spinning beam. The hot air pre-consolidation devices 9, 9' are preferably arranged in the form of hot air knives and / or hot air fields.

[0085] Within the scope of the method according to the invention and according to Figure 1In the embodiment of the present invention, a nonwoven web 2 consisting of crimped continuous filaments 10 is first produced by the first spinning beam 3 and laid on the laying screen belt 4. Subsequently, the nonwoven web 2 is preferably and in this embodiment pre-consolidated by means of a hot air pre-consolidation device 9. Then, a second nonwoven web 2' made of crimped continuous filaments 10 is suitably produced by the second spinning beam 3' and laid on the first nonwoven web 2. It is recommended that the second nonwoven web 2' or an aggregate consisting of the first nonwoven web 2 and the second nonwoven web 2' is then pre-consolidated with a second hot air pre-consolidation device 9', and then preferably peeled off from the laying screen belt 4 and conveyed to a calender 6 with a calender roller 5. With the aid of the calender roller 5 of the calender 6, an embossed pattern 11 consisting of a plurality of embossing portions 12 is preferably and in this embodiment introduced into the nonwoven 1 and the nonwoven 1 is suitably consolidated therein. Subsequently, a consolidation or main consolidation of the nonwoven 1 preferably takes place by means of at least one hot air main consolidation device 8 .

[0086] Figure 2 The basic structure of a part of an apparatus 14 for producing a nonwoven fiber web 2 according to the present invention by a spunbond method is shown, which comprises a spinning nozzle or a spinning manifold 3 for spinning continuous filaments 10, which is used for a spunbond nonwoven fiber web 2 composed of continuous filaments 10. The continuous filaments 10 spun by the spinning nozzle or the spinning manifold 3 are introduced into a cooling device 18 having a cooling chamber 19. Preferably and in this embodiment, air supply cabins 20, 21 are arranged one above the other on two opposite sides of the cooling chamber 19. Preferably, air of different temperatures is introduced into the cooling chamber 19 from the air supply cabins 20, 21 that are stacked one above the other.

[0087] Recommendedly and in this embodiment, a stretching device 22 for stretching the continuous filaments 10 is connected downstream of the cooling device 18 in the filament flow direction. Suitably and in this embodiment, the stretching device 22 has an intermediate channel 23, which connects the cooling device 18 with a stretching shaft 24 of the stretching device 22. Preferably and in this embodiment, the unit consisting of the cooling device 18, the intermediate channel 23 and the stretching shaft 24 is constructed as a closed unit, and except for the cooling air in the cooling device 18, no other air is supplied to the unit from the outside.

[0088] Suitably and in this embodiment, a diffuser 25 is connected to the stretching device 22 in the direction of the filament flow, through which the continuous filament 10 is guided. After passing through the diffuser 25, the continuous filament 10 is preferably and in this embodiment laid on a laying device configured as a laying screen belt 4. The laying screen belt 4 is preferably and in this embodiment implemented as a continuously surrounding laying screen belt 4. Within the scope of the present invention, the laying screen belt 4 is air-permeable, so that process air can be sucked from below through the laying screen belt 4.

[0089] Figure 3 and Figure 4 A nonwoven 1 according to the invention having at least one nonwoven web 2 consisting of fibers is shown. In this embodiment, the nonwoven 1 has two nonwoven webs 2, 2' consisting of continuous filaments 10 and is in particular configured as a nonwoven laminate. The continuous filaments 10 are preferably and in this embodiment crimped continuous filaments 10. Preferably and in this embodiment, the nonwoven 1 is a spunbond nonwoven having two spunbond nonwoven webs 2, 2' consisting of crimped continuous filaments 10. In this embodiment, the crimped continuous filaments 10 may be bicomponent filaments with an eccentric sheath-core configuration, wherein the sheath of the continuous filaments 10 is preferably composed of polyethylene or essentially composed thereof, and wherein the core of the continuous filaments 10 is in particular composed of at least one polyester and / or composed of polypropylene or essentially composed thereof.

[0090] also, Figure 3 and Figure 4 It is shown that the nonwoven 1 has an embossed pattern 11, wherein the embossed pattern 11 consists of a plurality of mutually unconnected embossed portions 12. The embossed pattern 11 is preferably and in this embodiment a regular embossed pattern 11, whose individual embossed portions 12 are preferably and in this embodiment distributedly arranged at regular intervals on the nonwoven 1.

[0091] Within the scope of the invention and in this exemplary embodiment, the embossing 12 has a size of 0.05 mm. 2 Up to 0.6mm 2 The embossing surface 13 of the embossed part 12 is within the scope of the present invention and in this embodiment refers in particular to the embossed surface of the embossed part 12, wherein when determining the size of the embossing surface 13, material protrusions or material flanges that may be formed during the pressing or embossing process and at least partially surround the embossed part 12 are not part of the embossing surface 13 of the embossed part 12. This is particularly Figure 4, which can be seen from the hatched illustration. Further preferably and in this embodiment, the embossing surfaces 13 of the individual embossing portions 12 of the embossing pattern 11 are of the same size or substantially of the same size. Preferably and in the embodiment according to the figures, the embossing surfaces 13 of the embossing portions 12 have a dot-shaped or circular geometry in a top view. Very particularly preferably and in this embodiment, the embossing pattern 11 has embossing portions 12 of the same or the same size or substantially the same or the same size, wherein the embossing portions 12 of the same or substantially the same geometry are uniformly distributed.

[0092] Within the scope of the present invention, the minimum spacing d between two embossed portions 12 of the embossed pattern 11 is respectively 0.6 to 3.0 mm. The minimum spacing d between two embossed portions 12 here refers in particular to the minimum spacing d between two directly adjacent embossed portions 12 of the embossed pattern 11, that is, preferably the minimum spacing d from one embossed portion 12 of the embossed pattern 11 to the embossed portion 12 closest to it. In addition, the minimum spacing d between two embossed portions 12 refers in particular to the minimum spacing d between the embossed boundaries of the two embossed portions 12, that is, the minimum spacing between the two embossed portions 12 along the non-embossed surface of the nonwoven 1 located therebetween.

[0093] The thickness h of the nonwoven 1 is preferably 0.15 to 0.75 mm. In the embodiment according to the drawings, the thickness h of the nonwoven 1 can be about 0.4 mm. The thickness h here refers to the maximum thickness or total thickness of the nonwoven 1 in the non-embossed area of ​​the nonwoven 1 transversely, in particular perpendicularly or substantially perpendicularly to the plane extension of the nonwoven. This can be particularly Figure 4 It can be seen in.

Claims

1. A method for producing a nonwoven (1), the nonwoven having at least one nonwoven web (2) made of fibers, wherein the fibers are produced by means of at least one fiber producing device, in particular by means of at least one spinning beam (3), wherein the fibers are subsequently laid on at least one laying device, in particular a laying screen belt (4), to form the nonwoven web (2), wherein the nonwoven web (2) or the nonwoven (1) is consolidated by means of at least one calender roller (5), in particular by means of at least one calender (6) having a calender roller (5) or a calender roller pair (5, 7), and wherein the nonwoven (1) is also consolidated or mainly consolidated by means of at least one hot fluid main consolidation device, in particular by means of at least one hot air main consolidation device (8).

2. The method according to claim 1, wherein the nonwoven (1) is peeled off the laying device before consolidation using the at least one calender roller (5) and / or before consolidation or main consolidation using the at least one hot fluid main consolidation device.

3. A method according to claim 1 or 2, wherein before or after consolidating or mainly consolidating the nonwoven (1) using the at least one hot fluid main consolidation device, in particular using at least one hot air main consolidation device (8), the nonwoven (1) is consolidated using the at least one calendering roller (5), in particular using at least one calendering machine (6) or calendering roller pair (5, 7) having the calendering roller (5).

4. The method according to any one of claims 1 to 3, wherein the nonwoven (1) is first pre-consolidated with at least one pre-consolidation device, preferably connected downstream of the at least one fiber producing device or the at least one spinning beam (3), in particular directly connected downstream thereof, after being laid on the laying device and before consolidation or main consolidation, preferably with at least one hot fluid pre-consolidation device, more preferably with at least one hot air pre-consolidation device (9), and wherein the at least one hot fluid pre-consolidation device or the hot air pre-consolidation device (9) is particularly preferably constructed in the form of a hot air knife and / or a hot air field.

5. The method according to any one of claims 1 to 4, wherein the at least one hot fluid main consolidation device or the at least one hot air main consolidation device (8) is preferably constructed in the form of a hot air furnace, particularly preferably an Ω furnace and / or a multi-drum furnace and / or a single-belt furnace and / or a double-belt furnace.

6. The method according to any one of claims 1 to 5, wherein the residence time of the nonwoven (1) in the hot fluid main consolidation device is 0.4s to 25s, preferably 1s to 15s, and / or wherein the fluid velocity of the fluid in the hot fluid main consolidation device is 0.4 to 3m / s, preferably 0.5 to 2m / s.

7. The method according to any one of claims 1 to 6, wherein the surface temperature T1 of the at least one calender roll (5), in particular of the at least one calender (7) having the calender roll (5) or of the calender roll pair (5, 7), is higher than the fluid temperature T2 of the at least one main hot-fluid consolidation device, preferably by 0.5 °C to 10 °C, preferably by 1 °C to 5 °C, or is lower than the fluid temperature T2 of the at least one main hot-fluid consolidation device, or is the same as or substantially the same as the fluid temperature T2 of the at least one main hot-fluid consolidation device.

8. The method according to any one of claims 1 to 7, wherein the fibres of the at least one nonwoven fibre web (2) are made or spun into continuous filaments (10), preferably crimped continuous filaments (10), wherein the continuous filaments (10) or the crimped continuous filaments (10) are particularly preferably made or spun into multi-component filaments, and very particularly preferably into bicomponent filaments.

9. The method according to claim 8, wherein the multi-component filament or the bicomponent filament has a first component with a preferably low melting point, which consists of or consists essentially of at least one thermoplastic, in particular of at least one polyolefin, preferably of polyethylene and / or of polypropylene, and / or wherein the multi-component filament or the bicomponent filament has a second or other component with a preferably higher melting point, which consists of or consists essentially of at least one thermoplastic, in particular of at least one polyester and / or of polypropylene.

10. The method according to claim 8 or 9, wherein the continuous filaments (10), preferably the crimped continuous filaments (10), are made or spun into multi-component filaments or bicomponent filaments having a side-by-side configuration and / or having a skin-core configuration, in particular an eccentric skin-core configuration, and wherein preferably the first component is the skin component and the second component is the core component.

11. The method according to any one of claims 9 or 10, wherein the surface temperature T1 of the at least one calender roll (5), in particular of the at least one calender (7) having the calender roll (5) or of the calender roll pair (5, 7), and / or the fluid temperature T2 of the at least one main hot-fluid consolidation device satisfy the following conditions with respect to the melting temperature Tm of the preferably low melting point first component of the multi-component filament or the bicomponent filament: (Tm - 15 °C) < T1 and / or T2 < (Tm + 15 °C), preferably (Tm - 10 °C) < T1 and / or T2 < (Tm + 10 °C), preferably (Tm - 8 °C) < T1 and / or T2 < (Tm + 8 °C), particularly preferably (Tm - 7 °C) < T1 and / or T2 < (Tm + 7 °C), very particularly preferably (Tm - 6 °C) < T1 and / or T2 < (Tm + 6 °C), for example (Tm - 5 °C) < T1 and / or T2 < (Tm + 5 °C).

12. The method according to claim 1, wherein an embossing pattern (11) consisting of a plurality of embossing portions (12) which are preferably not connected to one another is introduced into the nonwoven (1) by means of the at least one calender roller (7), wherein the embossing portions (12) preferably each have a diameter of 0.05 to 0.6 mm. 2 , preferably 0.06 to 0.4 mm 2 , preferably 0.07 to 0.25 mm 2 , particularly preferably 0.08 to 0.15 mm 2 , and very particularly preferably 0.09 to 0.12 mm 2 The stamping surface (13) of the embodiment of the present invention is provided.

13. The method according to claim 12, wherein the embossing pattern (11) is manufactured to the following specifications, namely, the minimum spacing d between two embossing parts (12) of the embossing pattern (11) is 0.6 to 3.0 mm, preferably 0.8 to 2.5 mm, preferably 0.9 to 2.0 mm, particularly preferably 0.95 to 1.8 mm and very particularly preferably 1.0 to 1.5 mm.

14. A method according to claim 12 or 13, wherein the embossed pattern (11) is manufactured to the following specifications, namely, the total embossed area of ​​the embossed pattern (11) accounts for 2 to 15% of the total surface area of ​​the nonwoven (1), preferably 2.5 to 12%, more preferably 3 to 8%, particularly preferably 3.5 to 6% and very particularly preferably 3.8 to 5.2%.

15. The method according to claim 1 , wherein a nonwoven (1) having at least two nonwoven webs (2, 2′) made of fibers is produced, wherein for this purpose first fibers are produced by at least one first fiber producing device, in particular by at least one first spinning beam (3), and the first fibers are subsequently laid on a laying device, in particular a laying screen belt (4), to form the nonwoven web (2), wherein second fibers are produced by at least one second fiber producing device, in particular by at least one second spinning beam (3′). , and subsequently laying the second fibers on the first nonwoven fiber web (2) to form a second nonwoven fiber web (2'), and wherein the aggregate or nonwoven (1) consisting of at least two nonwoven fiber webs (2, 2') is consolidated using at least one calender roller (5), in particular using at least one calender (6) or calender roller pair (5, 7) having the calender roller (5), and wherein the nonwoven (1) is also consolidated or mainly consolidated using at least one hot fluid main consolidation device, in particular using at least one hot air main consolidation device (8).

16. A device for preparing a nonwoven (1) having at least one nonwoven fiber web (2) made of fibers, in particular for implementing a method according to any one of claims 1 to 15, wherein the device (14) has at least one fiber producing device, in particular at least one spinning beam (3) and at least one laying device, in particular at least one laying screen belt (4), for laying the fibers into a nonwoven fiber web (2), wherein at least one calendering roller (5), in particular a calendering machine (6) having the calendering roller (5) or a calendering roller pair (5, 7) having the calendering roller, is also provided for consolidating the nonwoven (1), and wherein there is also at least one hot fluid main consolidation device, in particular at least one hot air main consolidation device (8), for consolidating or main consolidating the nonwoven.

17. An apparatus according to claim 16, wherein the at least one calendering roller (5), in particular the calendering machine (6) having the calendering roller (5) or the calendering roller pair (5, 7) is arranged before or after the at least one hot fluid main consolidation device in the conveying direction F of the non-woven (1).

18. The device according to claim 16 or 17, wherein the at least one calender roller (5) has a complementary embossing pattern (15) consisting of embossing elements (16) for introducing an embossing pattern (11) consisting of a plurality of embossing portions (12) into the nonwoven (1), wherein the embossing elements (16) preferably have a diameter of 0.05 to 0.6 mm, respectively. 2 , preferably 0.06 to 0.4 mm 2 , preferably 0.07 to 0.25 mm 2 , particularly preferably 0.08 to 0.15 mm 2 , and very particularly preferably 0.09 to 0.12 mm 2 The pressing surface (17) of the embodiment of the present invention is provided.

19. A nonwoven produced according to the method according to any one of claims 1 to 15 and / or using the apparatus according to any one of claims 16 to 18.

20. The nonwoven according to claim 19, wherein the nonwoven (1) has an embossed pattern (11) consisting of a plurality of embossed portions (12) which are preferably not connected to one another, the embossed portions (12) preferably each having a diameter of 0.05 to 0.6 mm. 2 , preferably 0.06 to 0.4 mm 2 , preferably 0.07 to 0.25 mm 2 , particularly preferably 0.08 to 0.15 mm 2 , and very particularly preferably 0.09 to 0.12 mm 2 The embossing surface (13), and / or the embossing surface (13) of the embossing portion (12) preferably has at least one geometric shape selected from the following group in a top view: "dot or circle, ellipse, square, rectangle, rhombus, polygon, line, wave".

21. The nonwoven according to claim 20, wherein the nonwoven (1) has a weight of less than 200 g / m 2 , especially less than 150g / m 2 , preferably less than 100g / m 2 , more preferably less than 75g / m 2 , particularly preferably less than 50g / m 2 and very particularly preferably less than 30 g / m 2 The nonwoven (1) has a weight per unit area of ​​0.1 to 1.0 mm, preferably 0.15 to 0.8 mm, more preferably 0.2 to 0.65 mm, particularly preferably 0.25 to 0.55 mm.

22. A nonwoven according to claim 20 or 21, wherein the nonwoven (1) has an abrasion resistance of at least level 2 according to the Martindale standard, preferably an abrasion resistance of level 1 according to the Martindale standard, and / or wherein the nonwoven (1) has a maximum bending stiffness of a cantilever of a maximum of 100 mm, more preferably a maximum of 90 mm, preferably a maximum of 80 mm, particularly preferably a maximum of 70 mm and very particularly preferably a maximum of 65 mm.

23. The nonwoven according to claim 20, wherein the nonwoven (1) is designed as a nonwoven laminate composed of at least two nonwoven fiber webs (2, 2') or nonwoven plies.

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