Nonwoven fabric and apparatus for manufacturing nonwoven fabric

Abstract

The present invention relates to a nonwoven fabric having at least one nonwoven web made of fibers. The nonwoven fabric has an embossed pattern. The embossed pattern consists of a plurality of (especially, non-connected to each other) embossments. Each of the embossments has an embossed surface ranging from 0.05 to 0.3 mm 2 up to.

Description

Technical Field

[0001] The present invention relates to a nonwoven fabric having at least one nonwoven web made of fibers, wherein the nonwoven fabric includes an embossed pattern, and the embossed pattern consists of a plurality of (preferably non-connected to each other) embosses. Further, the present invention also relates to an apparatus and a method for manufacturing such a nonwoven fabric having at least one nonwoven web made of fibers.

Background Art

[0002] Nonwoven fabrics, as well as apparatuses and methods for manufacturing nonwoven fabrics of the type described at the beginning, are basically known in various embodiments in practice. Usually, the produced fibers are deposited on a deposition device to form a nonwoven web, and then pre-fixed, thereby ensuring the transportability of the nonwoven web or nonwoven fabric and ensuring that the nonwoven web is not displaced or damaged when passing through the apparatus during transportation. For further fixation, the nonwoven fabric is usually peeled off from the deposition device and fed, for example, to a calendar having at least one calendar roller, in particular a pair of calendar rollers. At this time, a calendar roller having an embossing element is often used, which introduces an embossed pattern consisting of a plurality of embosses into the nonwoven fabric during the fixation process. By known calendar steps, satisfactory fixation, in particular an advantageous mechanical stability of the resulting nonwoven fabric, is achieved. However, the means known from the practice of using a calendar with at least one embossing element for fixing the nonwoven fabric have the disadvantages that the thickness and volume of the nonwoven fabric are impaired by this fixing means, and in addition, a visually recognizable embossed pattern (especially due to the dimensions of the embosses) is present in the nonwoven fabric. Although this embossed pattern is advantageous or necessary with respect to the mechanical properties of the nonwoven fabric, it is disadvantageous for aesthetic reasons because the visual properties are thereby adversely affected. Further, the embossed pattern or emboss formed by known means may be disadvantageous for further handling or processing of the nonwoven fabric.

Summary of the Invention

Problems to be Solved by the Invention

[0003] In contrast, the present invention is a nonwoven fabric of the type described at the beginning, which can effectively and surely avoid the drawbacks described above, and in particular, features advantageous mechanical properties such as sufficient mechanical strength or surface durability, and a satisfactory thickness or volume, and can reduce or largely avoid visual loss due to an embossing pattern consisting of embossings. It is based on the technical problem of providing the nonwoven fabric. Furthermore, the present invention is based on the technical problem of providing an apparatus and a method for manufacturing such a nonwoven fabric.

Means for Solving the Problems

[0004] To solve the above technical problem, the present invention is a nonwoven fabric having at least one nonwoven web made of fibers, wherein the nonwoven fabric has an embossing pattern, and the embossing pattern is composed of a plurality of (preferably not connected to each other) embossings, and each of the embossings has an embossed surface ranging from 0.05 to 0.3 mm 2 up to, especially from 0.06 to 0.2 mm 2 up to, preferably from 0.07 to 0.18 mm 2 up to, particularly preferably from 0.08 to 0.15 mm 2 up to, very particularly preferably from 0.09 to 0.12 mm 2 up to. The present invention teaches the nonwoven fabric having an embossed surface. Each of the embossings has an embossed surface less than 0.3 mm 2 especially less than 0.2 mm 2 less than, preferably less than 0.18 mm 2 less than, particularly preferably less than 0.15 mm 2 less than, extremely particularly preferably less than 0.12 mm 2 less than, for example, less than 0.1 mm 2 It is also within the scope of the present invention to have an embossed surface less than.

[0005] Within the scope of the present invention, the term "embossment" particularly means a densified portion of the nonwoven fabric, i.e., the nonwoven fabric has a particularly thinner thickness compared to the area where it has not been embossed, and the fibers of the nonwoven fabric are at least partially joined or fused together, especially by the action of pressure and / or temperature. The embossment according to the present invention of the embossment pattern is preferably formed by at least one calendar roller having a complementary embossment pattern consisting of embossment elements. This will be explained in more detail below.

[0006] Within the scope of the present invention, the term "embossment pattern" particularly means a pattern formed from a plurality of embossments of the nonwoven fabric. The embossment pattern can be a regular embossment pattern and / or an irregular embossment pattern. It is preferred that the embossment pattern is a regular embossment pattern. In this case, each embossment is distributed on the nonwoven fabric, especially at regular intervals, preferably at the same interval. More preferably, in one of the preferred embodiments of the present invention, the embossment surfaces of each embossment of the embossment pattern are of the same width or essentially of the same width. It has also been found advantageous that the geometric shape of the embossment surface of each embossment is the same or essentially the same. It is highly particularly preferred that the embossment pattern has embossments of the same or the same size, or essentially the same or the same size, and the embossments of the same geometric shape or essentially the same geometric shape are uniformly distributed. However, in principle, it is also possible that each embossment of the embossment pattern has a different size and / or a different geometric shape from each other, and / or the embossments are arranged on the nonwoven fabric in an irregular embossment pattern. Within the scope of the present invention, the geometric shape of the embossment means, among other things, the geometric shape of the embossment surface of the embossment as seen from above.

[0007] Within the framework of the present invention, the embossed surface of an embossment, in particular, means the surface of the embossment that has been embossed, and in determining the area of the embossed surface, material protrusions or material ridges that are formed during the process of pressing or embossing and that at least partially surround the embossment are not, in particular, part of the embossed surface of the embossment. In the case of an embossment or an embossed surface having a dot-shaped or circular geometry when viewed from above, the embossed surface of the embossment corresponds, for example, to the area of the dot-shaped or circular embossment, and in this case, material protrusions or material ridges that surround the embossment are not added to the embossed surface of the embossment. The fact that the embossments of the nonwoven fabric according to the present invention each have an embossed surface within the above range means that, within the framework of the present invention, in particular, at least 95%, especially at least 97% of all the embossments of the nonwoven fabric have an embossed surface within the above range. Particularly preferably, all the embossments of the nonwoven fabric have an embossed surface within the above range. The embossed surface area of the embossment can, within the framework of the present invention, in particular, be determined by means of reflected illumination or transmitted illumination 2D microscopy, and / or scanning electron microscopy (REM) and / or microcomputer tomography (μCT). In the corresponding image evaluation, preferably, the shape that forms the basis of the embossed surface geometry, or a geometry that coincides with or essentially coincides with the embossed surface geometry, is used as the basis, and for the evaluation, it is placed on the embossed surface of each optically imaged embossment.

[0008] The fact that the nonwoven fabric has at least one nonwoven web made of fibers means, within the framework of the present invention, in particular, that the nonwoven fabric has at least one nonwoven web or nonwoven layer made of fibers that have been manufactured and deposited. According to one embodiment, the nonwoven fabric can have just one nonwoven web or nonwoven layer, or it can have a plurality of laminated nonwoven webs or nonwoven layers that are combined to form a nonwoven laminate. This will be explained in more detail below.

[0009] The present invention has found that, by means of the embossing according to the invention of a non-woven fabric having an embossed surface of a particular width, the visual loss due to the embossed pattern consisting of the embossing can be almost completely avoided based on the recognizability of the embossed pattern which is at least clearly reduced to the human eye, and nevertheless, a non-woven fabric can be provided which features advantageous mechanical properties and a satisfactory thickness.

[0010] One particularly preferred embodiment of the present invention is that the embossed pattern is an invisible or essentially invisible embossed pattern, wherein the embossing is formed as an invisible or essentially invisible embossing. In this context, invisible means, in particular, that the embossed pattern of the non-woven fabric or the embossing of the non-woven fabric cannot be recognized or is essentially unrecognizable to the human eye.

[0011] The minimum distance d between two embosses of the emboss pattern is, respectively, from 0.6 to 2.5 mm, especially from 0.8 to 2.0 mm, preferably from 0.9 to 1.8 mm, particularly preferably from 0.95 to 1.6 mm, and very particularly preferably from 1.0 to 1.5 mm within the scope of the present invention. For practical purposes, the minimum distance d between two embosses of the emboss 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 very particularly preferably at least 2.0 mm. In this case, the minimum distance d between two embosses of the emboss pattern particularly means the minimum distance d between two directly adjacent embosses of the emboss pattern, that is, preferably, the minimum distance between one emboss and the nearest emboss of the emboss pattern. Further, the minimum distance d between two embosses of the emboss pattern particularly refers to the minimum distance between the respective emboss boundaries of the two embosses, that is, the minimum distance between these two embosses along the non-embossed nonwoven fabric surface existing between the two embosses. This embodiment is based on the finding that the visual recognition of the emboss pattern composed of embosses can be further reduced, while nevertheless ensuring the advantageous mechanical properties and sufficient thickness of the nonwoven fabric. The minimum distance between two embosses of the emboss pattern described above preferably applies to at least 95%, especially at least 97% of all the embosses of the nonwoven fabric. Particularly preferably, the above-mentioned minimum distance between two embosses applies to all the embosses of the nonwoven fabric.

[0012] According to a particularly preferred embodiment of the nonwoven fabric of the present invention, the ratio of the total embossed surface of the embossed pattern to the entire surface of the nonwoven fabric is from 2 to 12%, particularly from 2.5 to 8%, preferably from 3 to 6%, particularly preferably from 3.5 to 5.5%, and very particularly preferably from 4 to 5%. It is within the scope of the present invention that the ratio of the total embossed surface of the embossed pattern to the entire surface of the nonwoven fabric is less than 10%, particularly less than 8%, preferably less than 6.5%, particularly preferably less than 5.5%, and very particularly preferably less than 5%. By the above-mentioned ratio of the total embossed surface of the embossed pattern to the entire surface of the nonwoven fabric, the visual recognition of the embossed pattern composed of embosses can be further reduced. Nevertheless, a nonwoven fabric with satisfactory mechanical properties is produced. In this regard, the total embossed surface of the embossed pattern particularly means the sum of the total embossed surfaces of the embossed pattern. The entire surface of the nonwoven fabric, within the scope of the present invention, particularly means the entire nonwoven fabric surface including the embossed area and the non-embossed area.

[0013] When viewed from above, it is recommended that the embossed surface of the emboss has at least one geometric shape selected from the group of "dot-shaped or circular, elliptical, square, rectangular, rhombic, polygonal, linear, wavy". As already described above, the embossed surface of the emboss particularly means the embossed surface of the emboss without including the material protrusions or material ridges that may surround the embossed surface in some cases. It is preferred that the embossed surface or embosses of the embossed pattern each have the same geometric shape or essentially the same geometric shape. However, it is also basically within the scope of the present invention that the embossed pattern has embossed surfaces or embosses of different geometric shapes. A very particularly preferred embodiment of the present invention is characterized in that when viewed from above, the embossed surface of the emboss or all embosses is dot-shaped or circular.

[0014] Furthermore, it is also within the scope of the present invention that the aspect ratio of the embossed surface of the embossment is less than 4, preferably less than 3, particularly preferably less than 2, for example equal to 1, respectively. In this regard, the aspect ratio of the embossed surface particularly means the ratio of the maximum length or the longitudinal extension of the embossed surface of one embossment to the maximum width or the widthwise extension of the embossed surface of the same embossment, for example, the ratio of the lengths of the symmetry axes. In the case of a dot-shaped or circular geometry when viewed from above the embossed surface of one embossment, the aspect ratio is equal to 1, for example. In the case of an elliptical geometry when viewed from above the embossed surface of one embossment, the aspect ratio corresponds to, for example, the ratio of the length of the major axis or the major semi-axis to the length of the minor axis or the minor semi-axis of the ellipse. In the case of a rectangular geometry when viewed from above the embossed surface of one embossment, the aspect ratio corresponds to, for example, the ratio of the length of the rectangle to the width of the rectangle. In the case of a rhombic geometry when viewed from above the embossed surface of one embossment, the aspect ratio corresponds to, for example, the ratio of the length of the longer diagonal to the length of the shorter diagonal of the rhombus. In the case of a square geometry when viewed from above the embossed surface of one embossment, the aspect ratio is equal to 1. In the case of a curve, particularly, the aspect ratio of the surrounding rectangle represents the aspect ratio of the embossed surface.

[0015] It is basically within the scope of the present invention that the fibers of the at least one nonwoven web are staple fibers or the at least one nonwoven web contains staple fibers. According to a preferred embodiment, the fibers of the at least one nonwoven web are endless filaments. Particularly preferably, the fibers of all nonwoven webs of the nonwoven fabric are endless filaments. Endless filaments differ from staple fibers, for example, in that they have a clearly shorter length, for example, from 1 mm to 60 mm, in terms of their substantially endless length.

[0016] As described above, according to a particularly preferred embodiment of the present invention, the fibers of the at least one nonwoven web are formed as endless filaments. In particular, the fibers of the at least one nonwoven web or of the at least one nonwoven web of the nonwoven fabric as endless filaments are formed from at least one thermoplastic, preferably from at least one polyolefin. The at least one polyolefin is preferably polypropylene and / or polyethylene. In principle, the endless filaments can also be produced from other thermoplastics, such as polyesters, such as polyethylene terephthalate (PET) and / or polylactide (PLA), and from mixtures of the thermoplastics described above. According to one embodiment, a copolymer of the above thermoplastics is used. Conventional additives, such as plasticizers, fillers, colorants and similar agents, may be metered into the above thermoplastics. It is within the scope of the present invention that the endless filaments of the at least one nonwoven web or of the at least one nonwoven web of the nonwoven fabric are produced as spunbond endless filaments. In principle, it is also possible that the endless filaments of the at least one nonwoven web or of one nonwoven web of the nonwoven fabric are produced as meltblown endless filaments.

[0017] According to a particularly preferred embodiment of the present invention, the fibers of the at least one nonwoven web are formed as crimped endless filaments, wherein the crimped endless filaments are preferably multicomponent filaments, particularly preferably bicomponent filaments.

[0018] In this regard, it has been found to be particularly effective that the multi-component filament or bi-component filament comprises a first component, which consists of or consists essentially of at least one thermoplastic, in particular at least one polyolefin, especially polyethylene and / or polypropylene, and / or that the multi-component filament or bi-component filament comprises a second or further component, which consists of or consists essentially of at least one thermoplastic, in particular at least one polyester and / or polypropylene. As the polyester, polyethylene terephthalate (PET) and / or polylactide (PLA) are particularly suitable for the purpose. In one embodiment, a copolymer of the plastics is used. Here or below, when referring to a multi-component filament or bi-component filament component, especially a plastic or polymer, as "consisting essentially of", this means in particular that the component or polymer is present in a proportion of at least 95% by weight, especially at least 97% by weight, preferably at least 98% by weight. The remaining percentage by weight can in particular be composed of additives such as plasticizers, fillers, colorants and the like.

[0019] According to one preferred embodiment of the invention, the first component of the multi-component filament or bi-component filament is formed on a polyethylene basis and, in particular, consists of or consists essentially of polyethylene. According to yet another preferred embodiment, the first component of the multi-component filament or bi-component filament is formed on a polypropylene basis and preferably consists of or consists essentially of polypropylene. Also, within the scope of the invention, at least one polypropylene copolymer can be used instead of or in addition to polypropylene.

[0020] In a preferred embodiment of the present invention, the second or further components of said multicomponent filament or bicomponent filament are formed based on at least one polyester and / or based on polypropylene. Particularly preferably, said second or further components of said multicomponent filament or bicomponent filament consist of at least one polyester and / or of polypropylene. For said second or further components, at least one polypropylene copolymer can also be used instead of or in addition to polypropylene, and in particular, at least one polyester copolymer can also be used instead of or in addition to polyester. As polyester, advantageously especially polyethylene terephthalate (PET) and / or polylactide (PLA) are suitable, and as polyester copolymer, especially PET copolymer (Co-PET) is suitable. Also, it is within the scope of the present invention to use a polylactide copolymer (Co-PLA) as the first component and polylactide (PLA) as the second or further components.

[0021] It is within the scope of the present invention that said endless filament, preferably a crimped endless filament, is formed as a multicomponent filament or bicomponent filament having a side-by-side configuration and / or a core-sheath configuration, in particular an eccentric core-sheath configuration, and preferably that the first component described above is the sheath component and, expediently, that the second or further components described above are the core components. When said endless filament is formed as a multicomponent filament or bicomponent filament having a core-sheath configuration, it is also in principle possible within the scope of the present invention for this to be a concentric core-sheath configuration.

[0022] When the endless filament or crimped endless filament is formed as a multi-component filament or bicomponent filament having an eccentric core-sheath configuration in a preferred embodiment, it is within the scope of the present invention that not only the sheath of the filament but also the core of the filament is formed in a circular shape when looking at the filament cross-section. In another preferred embodiment of the present invention, the multi-component filament or bicomponent filament has an eccentric core-sheath configuration, and the core of these filaments is formed in a bow shape when looking at the filament cross-section, and has an arcuate peripheral section and a linear peripheral section with respect to its periphery, resulting in a so-called D-shaped core when looking at the filament cross-section.

[0023] When the endless filament or crimped endless filament is a multi-component filament or bicomponent filament having at least one of the first components and at least one of the second or more components within the scope of the present invention, it is preferable that the first component is a component having a lower melting point than the second component. The first or lower melting point component is preferably polyethylene and / or polypropylene, particularly polyethylene. In one of the preferred embodiments, the proportion of the lower melting point first component of the multi-component filament or bicomponent filament of the at least one non-woven web of the non-woven fabric is from 20 to 80% by weight, especially from 25 to 65% by weight, preferably from 30 to 50% by weight, based on the components of the multi-component filament or bicomponent filament. The lower melting point component or lower melting point first component of the multi-component filament or bicomponent filament is, in particular, a binding component of the multi-component filament or bicomponent filament within the scope of the present invention.

[0024] In a particularly preferred embodiment of the nonwoven fabric according to the present invention, the fineness of the fibers of the nonwoven fabric, particularly the fineness of the endless filament or the crimped endless filament, is from 0.5 to 6.0 den, preferably from 0.8 to 5.0 den, and particularly preferably from 1.0 to 2.5 den.

[0025] One of the recommended embodiments of the present invention is that the nonwoven fabric has a basis weight of less than 200 g / m 2 and particularly less than 150 g / m 2 and especially less than 100 g / m 2 and preferably less than 75 g / m 2 and particularly preferably less than 50 g / m 2 and very particularly preferably less than 30 g / m 2 It is characterized by having a basis weight. When the basis weight of the nonwoven fabric is from 10 g / m 2 to 80 g / m 2 and especially from 15 g / m 2 to 60 g / m 2 and preferably from 15 g / m 2 to 30 g / m 2 is particularly preferred.

[0026] It is highly preferred that the nonwoven fabric has a thickness h of from 0.1 to 0.85 mm, especially from 0.15 to 0.75 mm, preferably from 0.2 to 0.65 mm, and particularly preferably from 0.25 to 0.55 mm. It is within the scope of the present invention that the nonwoven fabric has a thickness h of at least 0.4 mm, particularly at least 0.5 mm, especially at least 0.55 mm, preferably at least 0.6 mm, and particularly preferably at least 0.625 mm. Herein, the thickness h means the maximum thickness or total thickness of the nonwoven fabric in a direction transverse to, particularly perpendicular or essentially perpendicular to, the plane extension of the nonwoven fabric in the non-embossed area thereof. At this time, the thickness or total thickness h of the nonwoven fabric is measured according to the method of WRT120.6(05)-Option A.

[0027] One of the embodiments that has proven to be very effective in the present invention is that the nonwoven fabric has a wear resistance of at least class 2 according to Martindale, especially a wear resistance of class 1 according to Martindale, and / or the nonwoven fabric has a maximum bending rigidity using a cantilever of up to 100 mm, especially up to 90 mm, preferably up to 80 mm, particularly preferably up to 75 mm, and very particularly preferably up to 70 mm. This embodiment is based on the finding that the nonwoven fabric features very satisfactory wear resistance and / or the nonwoven fabric also has an advantageously low bending rigidity and in particular improved drapability compared to known means or nonwoven fabrics. These properties occur in the nonwoven fabric according to the present invention, in particular, in an advantageous combination of satisfactory mechanical strength and at least a clearly reduced visual recognition of the embossed pattern consisting of embossing. The wear resistance of the nonwoven fabric is determined within the framework of the present invention, in particular, using a Martindale wear tester according to the following test method.

[0028] As the tester, in particular, a machine called "SDL Atlas M235 Martindale Tester" is used. The way to determine the wear resistance is based especially on WSP20.5(05), and in this case, in particular, the following deviations from WSP20.5(05) are defined: The surfaces (upper / lower) are tested separately; at least 10 tests, preferably at least 20 tests, are carried out for one sample and one surface. At this time, the test pieces are evenly obtained from the surface of the sample, and the final result is the arithmetic mean value. The test pieces should be obtained from representative positions, not just from the edges, because the deviations in the test or the results should be affected only by typical (local) variations, not by macroscopic deviations, such as poor process control; The test sample is stretched on a standard felt and attached to the lower holder; As the moving upper friction surface, the same nonwoven fabric is used so that the test sides face each other. This piece is fixed together with a PU foam plastic patch (for example, manufactured by SDL Atlas); A pressing force of 9 kPa; 32 cycles, that is, two complete loops of the Lissajous figure; After each test, the pair (test piece and upper friction surface) is exchanged; The sample is evaluated on a scale of 1 to 5, where 1 is the best score. For example, if the average value is 1 on the upper side and 3 on the lower side, the sample is evaluated as 1 overall. When evaluating only the changes in the non-woven fabric, if this non-woven fabric has similar defects beforehand, these can be overlooked. This means, for example, fiber tufts (groups or bundles of fibers on the surface). If the test piece clearly shows these defects from the beginning, that test piece should preferably be excluded if in doubt.

[0029] Score 1: When viewed from above, there is virtually no change. There may be some signs of loosening on the surface, but the filaments are only loose and should not form large or long agglomerates. When viewed from the side, the fuzz height of the loose filaments should not exceed 5 mm. Individual filaments or multiple filaments may gather together to form small globules with a diameter of less than 2 mm.

[0030] Score 2: In addition to the above damage pattern (Score 1): The filaments are loose and tangle with adjacent filaments to form long aggregates. These groups of filaments are referred to as "tufts" or "strings or bundles". These tufts are 5 to 40 mm in length and are attached to the substrate at least every 10 mm. One tuft has a maximum height of 5 mm (protruding 5 mm from the surface) and a maximum width of 2 mm.

[0031] Score 3: The above-mentioned "tuft" is no longer attached to the substrate along its length, and if there are attachment parts, they are more than 10 mm apart from each other, or in this case, the tuft is only attached to the sample at the starting point and the ending point. This tuft can be lifted and moved, for example, using a needle.

[0032] Score 4: The tufts are joined to adjacent tufts to form a network. "Spider web" Score 5: The sample is further damaged and the formation of the first hole has occurred.

[0033] The bending rigidity of the nonwoven fabric is determined, within the framework of the present invention, in particular, according to the method of "WSP90.1(05) Standard Test Method for Stiffness of Nonwoven: Fabrics Using the Cantilever Test".

[0034] Within the framework of the present invention, it is that the strength of the nonwoven fabric in the machine direction (MD direction) is at least 8 N / 5 cm, particularly at least 10 N / 5 cm, especially at least 15 N / 5 cm, preferably at least 17.5 N / 5 cm, particularly preferably at least 20 N / 5 cm, and very particularly preferably at least 22.5 N / 5 cm. The machine direction (MD direction) means, within the framework of the present invention, in particular, the conveying direction F of the nonwoven fabric on the deposition device. The strength of the nonwoven fabric in the machine direction is determined, within the framework of the present invention, in particular by the following method: "Determination of Tensile Strength (Edana20.2 - 89 standard)": unit of N / 5 cm; sample width of 50 mm; grip length of 100 mm; test speed of 200 mm / min.

[0035] In one particularly preferred embodiment of the present invention, the depth t of the embossment is from 0.1 to 0.8 mm, preferably from 0.15 to 0.7 mm, particularly preferably from 0.2 to 0.6 mm, and very particularly preferably from 0.25 to 0.5 mm, respectively. Here, the depth t of the embossment particularly means the difference in thickness between the thickness or total thickness h of the nonwoven fabric and the thickness of the nonwoven fabric in the range of the embossed surface of the embossment. At this time, the total thickness h of the nonwoven fabric is particularly determined according to the above method. The thickness of the nonwoven fabric in the range of the embossed surface of the embossment can be determined, within the framework of the present invention, for example, by visual or microscopic analysis of the cross-section of the nonwoven fabric. This is possible, for example, by pouring a sample having a cross-section passing through the embossment point and polishing the cut surface. Then, on this cut surface, the depth of the embossed surface can be determined from the side using a typical microscope. For relatively light basis weights, the embossed surface can be porous, and in this case, it is preferable to determine the thickness only at the formed part. Additionally or alternatively, a micro-computed tomography (μCT) scan enabling determination of the average thickness of the embossed surface is suitable.

[0036] It is within the scope of the present invention for the nonwoven fabric to have only one nonwoven web or only one nonwoven layer. The nonwoven web or nonwoven layer can be, for example, a nonwoven web made of endless filaments, especially endless crimped filaments. In a preferred embodiment, the nonwoven fabric as a nonwoven laminate is composed of at least two nonwoven webs or nonwoven layers, especially at least two of the aforementioned nonwoven webs or nonwoven layers. It is preferred that the fibers of the at least two nonwoven webs or nonwoven layers of the nonwoven fabric, especially the fibers of all the nonwoven webs or nonwoven layers of the nonwoven fabric, are endless filaments or endless crimped filaments. However, in principle, the nonwoven fabric can also have a nonwoven web or nonwoven layer having fibers made of non-crimped endless filaments or staple fibers. It has been found effective that the fibers of at least one nonwoven web or nonwoven layer assigned to the outer surface of the nonwoven fabric are endless crimped filaments and / or staple fibers. Thereby, in particular, the flexibility of the nonwoven fabric can be improved and the bending stiffness can be reduced. Furthermore, it is also possible for the fibers or the properties of the endless filaments of the different nonwoven webs or nonwoven layers of the nonwoven fabric to be different. For example, the endless filaments of the first nonwoven web can have a relatively smaller average fineness than the endless filaments of the second nonwoven web, so as to create a fineness gradient so to speak.

[0037] In one preferred embodiment of the present invention, the nonwoven fabric is a spunbond nonwoven fabric having at least one spunbond nonwoven web or at least one spunbond nonwoven layer. The nonwoven fabric as a nonwoven laminate can be composed of at least two spunbond nonwoven webs or at least two spunbond nonwoven layers. However, it is also possible for the nonwoven laminate to have at least one meltblown nonwoven layer or meltblown nonwoven web. Furthermore, it is within the scope of the present invention for the nonwoven fabric as a nonwoven laminate to be composed of at least three, for example at least four, nonwoven webs or nonwoven layers. Each individual nonwoven web or nonwoven layer can be configured as a spunbond nonwoven web or nonwoven layer, respectively. However, in principle, the nonwoven laminate can also have at least one meltblown nonwoven web or meltblown nonwoven layer. The spunbond nonwoven web or spunbond nonwoven layer is preferably composed of endless filaments or crimped endless filaments, respectively.

[0038] One embodiment of the present invention that has been found to be effective is characterized in that the nonwoven fabric is fixed using at least one calendar roller to generate an embossed pattern and, in particular, using at least one hot-fluid type main fixing device, particularly at least one hot-air type main fixing device. The at least one calendar roller is, in particular, part of a calendar, preferably part of a calendar including at least two calendar rollers or at least one pair of calendar rollers. When the nonwoven fabric is fixed using at least one calendar roller to generate an embossed pattern and at least one hot-fluid type main fixing device in a preferred embodiment, in particular, a nonwoven fabric is produced that features advantageous visual properties, particularly advantageous mechanical strength, and at the same time advantageously low bending stiffness and sufficient abrasion resistance.

[0039] The term "hot fluid" means, within the framework of the present invention, a temperature-controlled or heated fluid. Preferably, the hot fluid is a temperature-controlled or heated gas, particularly preferably hot air. However, in principle, the hot fluid can also be a temperature-controlled or heated liquid, such as water.

[0040] The present invention further relates to the use of said nonwoven fabric for at least one hygiene product or in at least one hygiene article.

[0041] To solve the above technical problem, the present invention further provides an apparatus for manufacturing a nonwoven fabric having at least one nonwoven web made of fibers, particularly for manufacturing said nonwoven fabric, the apparatus comprising at least one fiber manufacturing device, particularly at least one spinning beam, and at least one depositing device for depositing fibers to form a nonwoven web, particularly at least one depositing screen belt, and further comprising at least one calendar roller for introducing an embossing pattern composed of a plurality of embossments into the nonwoven fabric, wherein the calendar roller has a complementary embossing pattern composed of embossing elements, and each of the embossing elements has a pressing surface ranging from 0.05 to 0.3 mm 2 up to, particularly from 0.06 to 0.2 mm 2 up to, preferably from 0.07 to 0.18 mm 2 up to, particularly preferably from 0.08 to 0.15 mm 2 up to, and very particularly preferably from 0.09 to 0.12 mm 2 up to, and the present invention teaches said apparatus.

[0042] It is within the scope of the present invention that the embossing elements of the complementary embossing pattern of the at least one calendar roller each have an embossing height in the range from 0.3 to 1.2 mm, preferably from 0.4 to 0.9 mm, and particularly preferably from 0.5 mm to 0.8 mm. In this case, the embossing height particularly means the height difference between the pressing surface of the embossing element and the base surface of the calendar roller. This embodiment is based on the finding that in a calendaring process using such a calendar roller, the consolidation of the nonwoven fabric can be at least significantly minimized.

[0043] For purposes, the deposition screen belt of the device according to the invention is an endless circulating deposition screen belt. It is within the scope of the present invention that the calendar roller is part of a calendar. The calendar is preferably arranged downstream of the deposition device or the deposition screen belt in the conveying direction F of the nonwoven fabric. In a particularly preferred embodiment, the calendar has at least one pair of calendar rollers, and at least one of the two calendar rollers of the calendar or the pair of calendar rollers, particularly one, is the above-described calendar roller for introducing an embossing pattern consisting of embossings into the nonwoven fabric. The other or further roller of the calendar or the pair of calendar rollers is, for purposes, a smoothing roller having a smooth outer surface. Therefore, in particular, the nonwoven fabric is fixed using a calendar including at least one of the above-described calendar rollers for introducing an embossing pattern consisting of a plurality of embossings into the nonwoven fabric and at least one smoothing roller. In this case, the embossing pattern is preferably introduced into the nonwoven fabric only from one nonwoven fabric surface. However, nevertheless, preferably, the embossing pattern is present on both nonwoven fabric surfaces in the resulting nonwoven fabric, and in this case, the embossing depth is distributed differently, in particular, on both nonwoven fabric surfaces.

[0044] The pressure surface means, within the framework of the present invention, in particular the surface of the embossing element of a calendar roller provided for generating the embossing surface of the emboss. When the embossing element of the calendar roller is formed as a cylindrical embossing element, for example, to generate an embossing surface having a dot-shaped or circular geometry when viewed from above, the pressure surface of the embossing element corresponds in particular to the surface of this cylindrical upper surface. When the embossing element of the calendar roller is formed, for example, in the shape of a frustum of a cone (i.e., with a flank angle) to generate an emboss having an embossing surface with a dot-shaped or circular geometry when viewed from above, the pressure surface of the embossing element corresponds in particular to the upper surface of the frustum of the cone. One embodiment of the present invention utilizes a plurality of flank angles for the embossing element, where the embossing element preferably has a larger flank angle the more it is directed towards the base surface of the calendar roller in the region provided for contact with the nonwoven fabric. In this case, the gradient of the flank angle can occur stepwise or continuously.

[0045] Therefore, the at least one calendar roller for introducing an embossing pattern consisting of a plurality of embosses into the nonwoven fabric is configured, within the framework of the present invention, in particular under the condition that the above-mentioned characteristics of the emboss can be realized (in particular with respect to the embossing surface and / or the minimum distance d between two embosses and / or the depth t of the emboss and / or the ratio of the total embossing surface of the embossing pattern to the entire surface of the nonwoven fabric and / or the aspect ratio of the embossing surface of the emboss).

[0046] It is within the scope of the present invention that the at least one fiber manufacturing device or the at least one spinning beam is configured to produce a spunbond nonwoven fabric from endless filaments, in particular from crimped endless filaments. When the nonwoven fabric is configured as a nonwoven laminate consisting of at least two nonwoven layers or nonwoven webs in one embodiment of the present invention, the presence of at least two fiber manufacturing devices, in particular at least two spinning beams, and in particular that all fiber manufacturing devices or spinning beams are designed to produce a spunbond nonwoven web from endless filaments, in particular from crimped endless filaments, is within the scope of the present invention. Very particularly preferably, the at least one fiber manufacturing device or the at least one spinning beam of the device according to the present invention, in particular all fiber manufacturing devices or all spinning beams, are designed to produce multicomponent filaments or bicomponent filaments. Furthermore, it is within the scope of the present invention that the device is configured to produce at least one nonwoven web from crimped endless filaments. In particular, the at least one fiber manufacturing device or the at least one spinning beam is designed for the production of crimped endless filaments. When a plurality of spinning beams are used for the device according to the present invention, at least one spinning beam, or at least two spinning beams, or all spinning beams are designed for the production of crimped endless filaments.

[0047] A highly advantageous form of the present invention is characterized in that for fibers or endless filaments spun using at least one fiber production device or at least one prevention beam, there is provided at least one cooling device for cooling the fibers or filaments, and a stretching device following the cooling device for stretching the fibers or filaments. Advantageously, this stretching device is followed by at least one diffuser in the flow direction of the fibers or filaments. One highly recommended embodiment of the present invention is to configure the connecting machine consisting of the cooling device and the stretching device as a closed-system connecting machine, and in this connecting machine, except for the supply of cooling air into the cooling device, no further air supply from the outside is carried out. Advantageously, the fibers or filaments emerging from the diffuser are deposited directly onto a deposition device or a deposition screen belt.

[0048] One particularly preferred embodiment of the device according to the present invention is that the device has at least one main heat-fluid fixing device, in particular a hot-air main fixing device, and in this case, the main heat-fluid fixing device is arranged, among other things, behind the calendar roller in the conveying direction F of the non-woven fabric. Therefore, in a preferred embodiment, the at least one main heat-fluid fixing device is arranged behind the calendar roller according to the present invention for introducing an embossing pattern consisting of embossings into the non-woven fabric in the conveying direction F of the non-woven fabric, and in particular, behind the calendar including this calendar roller. The main heat-fluid fixing device or the hot-air main fixing device can in particular be a hot-air oven for fixing or mainly fixing the non-woven fabric.

[0049] Within the framework of the present invention, it has been found to be particularly effective that the at least one heat-fluid main fixing device or the at least one hot-air main fixing device is configured as a hot-air oven, particularly preferably as an omega oven and / or as a multi-drum oven and / or as a single-belt oven and / or as a double-belt oven. Expediently, the fixing or main fixing using at least one heat-fluid main fixing device is effected in the at least one heat-fluid main fixing device by applying at least one heat fluid to one or both sides of the nonwoven fabric. If the heat-fluid main fixing device, particularly the hot-air main fixing device, is a hot-air oven in a preferred embodiment, then, in other respects, the fluid temperature corresponds in particular, within the framework of the present invention, to the temperature of the hot air during this hot-air fixing in the hot-air oven. In principle, the at least one heat-fluid main fixing device can also be arranged, in other respects, in the transport direction F of the nonwoven fabric in front of the calendar roller or in front of the calendar comprising this calendar roller.

[0050] The device comprises at least one pre-fixing device, particularly at least one heat-fluid pre-fixing device, preferably at least one hot-air pre-fixing device, wherein the pre-fixing device is arranged, particularly preferably, in the transport direction F of the nonwoven fabric in front of the calendar roller, particularly in front of the calendar or calendar roller pair comprising this calendar roller, and very particularly preferably is installed after or arranged directly after the at least one fiber production device or the at least one spinning beam. It has been found to be effective that, inter alia, the at least one pre-fixing device is also arranged in the transport direction F of the nonwoven fabric in front of the preferably provided heat-fluid main fixing device.

[0051] It is within the scope of the present invention that a pre - fixing device or a hot - fluid - type pre - fixing device is arranged above the deposition device or the deposition screen belt. Additionally, it is within the scope of the present invention that the at least one hot - air - type pre - fixing device is configured in the form of at least one hot - air knife and / or in the form of at least one hot - air field. However, in principle, the pre - fixing device can also be at least one roller or smoothing roller, in particular a pair of rollers or a pair of smoothing rollers. When the device according to the present invention has at least two fiber - manufacturing devices or at least two spinning beams, each fiber - manufacturing device or each spinning beam is, in the conveying direction F of the non - woven fabric, installed behind or immediately after at least one pre - fixing device, in particular at least one hot - fluid - type pre - fixing device or hot - air - type pre - fixing device, and expediently, the hot - air - type pre - fixing device is formed in the form of a hot - air knife and / or in the form of a hot - air field respectively. When the non - woven fabric is manufactured using only one non - woven web in one embodiment, it is preferable to use a hot - air knife as the pre - fixing device. When the non - woven fabric is manufactured using a plurality of non - woven webs or non - woven layers in a preferred embodiment, in particular for the non - woven web or non - woven layer deposited on the topmost or last, a hot - air knife is used as the pre - fixing device, and for the remaining non - woven webs or non - woven layers, in particular, a hot - air knife and a hot - air field are used as the pre - fixing device.

[0052] To solve the above technical problem, the present invention further provides a method for manufacturing a non-woven fabric having at least one non-woven web made of fibers, particularly for manufacturing the above non-woven fabric and / or using the above apparatus, wherein the fibers are manufactured using at least one fiber manufacturing device, particularly at least one spinning beam, and the fibers are then deposited on at least one deposition device, particularly on at least one deposition screen belt, to form a non-woven web. The non-woven web or non-woven fabric is then fixed using at least one calendar roller, and an embossing pattern consisting of a plurality of embossments is introduced into the non-woven fabric using this calendar roller. Here, each of these embossments has an embossed surface ranging from 0.05 to 0.3 mm 2 up to, particularly from 0.06 to 0.2 mm 2 up to, preferably from 0.07 to 0.18 mm 2 up to, particularly preferably from 0.08 to 0.15 mm 2 up to, very particularly preferably from 0.09 to 0.12 mm 2 up to, and the present invention teaches the above method.

[0053] It is within the scope of the present invention that the non-woven fabric is fixed, particularly primarily fixed, using at least one thermal fluid main fixing device, particularly at least one hot air main fixing device, (particularly following fixation using at least one calendar roller, particularly at least one calendar or pair of calendar rollers having the calendar roller).

[0054] According to a preferred embodiment of the method of the present invention, after the nonwoven fabric is deposited on a deposition device, particularly on a deposition screen belt, it is first pre-fixed using at least one pre-fixing device, particularly using at least one thermal fluid pre-fixing device, especially using at least one hot air pre-fixing device. Then, it is fixed using at least one calendar roller according to the present invention, and then fixed, particularly main-fixed, using a thermal fluid main-fixing device or a hot air main-fixing device. It is also possible to first fix or pre-fix the nonwoven fabric using a thermal fluid main-fixing device after pre-fixing, and then fix it using at least one calendar roller according to the present invention. Pre-fixing means, within the framework of the present invention, particularly ensuring transportability, but especially resulting in a lower degree of fixation of the nonwoven fabric compared to fixation or main-fixation, meaning the fixation of the nonwoven fabric or nonwoven web.

[0055] According to a preferred embodiment, when a nonwoven fabric having at least two nonwoven webs or nonwoven layers is produced or when an apparatus having at least two fiber production devices or at least two spinning beams is provided, preferably, first, a first nonwoven web is produced from at least one first spinning beam, and deposited on a deposition device, in particular on a deposition screen belt, and in particular pre-fixed using a first pre-fixing device or a thermal fluid pre-fixing device. Then, preferably, a second nonwoven web produced using a second fiber production device or a second spinning beam is deposited on the first nonwoven web, and then this second nonwoven web, or the assembly of the first nonwoven web and the second nonwoven web, is pre-fixed using at least one further separate pre-fixing device or a thermal fluid pre-fixing device. Preferably, then, the nonwoven fabric is peeled off from the deposition device and supplied to the calendar comprising at least one calendar roller of the present invention or the like. Using the calendar roller of the calendar, an embossing pattern composed of a plurality of embossings is expediently introduced into the nonwoven fabric, and in this case, in particular, the nonwoven fabric is fixed. Expediently, then, the nonwoven fabric is fixed or main-fixed using a thermal fluid main-fixing device or a hot air main-fixing device.

[0056] Within the scope of the present invention, the surface temperature of the at least one calendar roller, in particular of the calendar or the pair of calendar rollers comprising the calendar roller, is higher than the temperature of the thermal fluid of the at least one thermal fluid main-fixing device, in particular 1 °C to 15 °C higher, preferably 1 °C to 5 °C higher, or lower than the temperature of the thermal fluid of the at least one thermal fluid main-fixing device, or the same as or essentially the same as the temperature of the thermal fluid of the at least one thermal fluid main-fixing device. Within the scope of the present invention, the at least one calendar roller, in particular the at least one calendar or the pair of calendar rollers comprising the calendar roller, is preferably a heated calendar roller or a heated calendar.

[0057] Furthermore, within the framework of the present invention, it is also possible for the fluid temperature of the at least one main heat-fluid fixing device to be in the range from Tm - 5°C to Tm + 10°C with respect to the melting point Tm of the first low-melting-point component described above for the multi-component filament or the bi-component filament. At this time, the melting temperature Tm of the first low-melting-point component is determined in accordance with ISO 11357-3:2011, particularly using a dynamic differential scanning calorimeter (DSC).

[0058] The present invention is based on the finding that the non-woven fabric according to the present invention is characterized by an embossed pattern consisting of embossments, whereby substantially complete avoidance of visual damage to the non-woven fabric can be achieved. Based on the special form of the embossments and the properties of the non-woven fabric, the recognizability of the embossed pattern for the human eye is at least clearly reduced, resulting in an embossed pattern that is almost invisible consisting of embossments. This is realized, according to the present invention, in particular by relatively small embossed surfaces of the embossments. The preferably set minimum distance between each two embossments of the embossed pattern and the ratio of the total embossed surface of the embossed pattern to the total surface of the non-woven fabric contribute advantageously to the at least clearly reduced recognizability of the embossed pattern for the human eye. Nevertheless, the non-woven fabric is characterized by advantageous mechanical properties and sufficient thickness. Furthermore, according to a preferred embodiment of the present invention, the non-woven fabric has very high abrasion resistance and low bending stiffness. Still further, it should be emphasized that the above-mentioned properties of the non-woven fabric can be realized within the framework of the present invention using means that are less laborious. This also applies in particular to the device and the method of the present invention.

[0059] The present invention will be explained in more detail below based on the drawings showing only one example.

Brief Description of the Drawings

[0060]

Figure 1

Figure 2

Figure 3

Figure 4

DETAILED DESCRIPTION OF THE INVENTION

[0061] FIGS. 1 and 2 show the nonwoven fabric 1 of the present invention provided with at least one nonwoven web 2 made of fibers. In the embodiment according to these figures, the nonwoven fabric 1 has two nonwoven webs 2, 2' made of endless filaments 6 and is particularly configured as a nonwoven laminate. The endless filaments 6 may be, among other things and in this embodiment, crimped endless filaments 6. Preferably and in this embodiment, the nonwoven fabric 1 is a spunbond nonwoven fabric having two spunbond nonwoven webs 2, 2' made of crimped endless filaments 6. The crimped endless filaments 6 may, in this embodiment, be bicomponent filaments having an eccentric core-sheath configuration, where the sheath of the endless filament 6 preferably consists of or consists essentially of polyethylene, and the core of the endless filament 6 consists of or consists essentially of, in particular, at least one polyester and / or polypropylene.

[0062] Furthermore, FIGS. 1 and 2 show that the nonwoven fabric 1 has an embossed pattern 3, where the embossed pattern 3 consists of a plurality of embossments 4 that are not connected to each other. Here, the embossment 4 particularly means a densified portion of the nonwoven fabric 1, that is, the nonwoven fabric 1 has a thinner thickness compared to the region where the nonwoven fabric 1 is not embossed, and the crimped endless filaments 6 of the nonwoven fabric 1 particularly mean a location where they are at least partially connected or fused to each other by the action of pressure and / or temperature. The embossed pattern 3 is preferably and in this embodiment a regular embossed pattern 3, and its individual embossments 4 are arranged in a state of being distributed on the nonwoven fabric 1 at regular intervals, among other things and in this embodiment.

[0063] In the present invention, each of the embossments 4 is from 0.05 to 0.3 mm 2It has an embossed surface 5 up to. The embossed surface 5 of the emboss 4, within the framework of the present invention and in this embodiment, particularly means the embossed surface of the emboss 4. In this case, when determining the area of the embossed surface 5, material protrusions or material ridges that are formed during the pressing or embossing process and at least partially surround the emboss 4 are not part of the embossed surface 5 of the emboss 4. This can be seen, in particular, in the hatched depiction in FIG. 2. More preferably and in this embodiment, the embossed surfaces 5 of the individual embosses 4 of the embossing pattern 3 are of the same size or essentially of the same size. In particular and in this embodiment according to these figures, the embossed surface 5 of the emboss 4 has a dot-shaped or circular geometry when viewed from above. Very particularly preferably and in this embodiment, the embossing pattern 3 has embosses 4 of the same or the same size, or essentially the same or the same size, and the embosses 4 of the same geometry or essentially the same geometry are uniformly distributed.

[0064] Within the framework of the present invention, the minimum distance d between two embosses 4 of the embossing pattern 3 is from 0.6 to 2.5 mm each. In this case, the minimum distance d between two embosses 4 particularly means the minimum distance d between two directly adjacent embosses 4 of the embossing pattern 5, that is, preferably, the minimum distance d between one emboss 4 and the emboss 4 closest to it in the embossing pattern 3. Further, the minimum distance d between two embosses 4 particularly means the minimum distance d between the respective emboss boundaries of the two embosses 4, that is, the minimum distance between these two embosses 4 along the surface of the non-woven fabric 1 that is not embossed and exists between the two embosses 4.

[0065] It has been found to be particularly effective that the ratio of the total embossed surface of the embossing pattern 3 to the total surface of the non-woven fabric 1 is from 2 to 12%. In this context, the total embossed surface of the embossing pattern 3 particularly means the sum of the total embossed surfaces 5 of the embossing pattern 3. The total surface of the non-woven fabric 1, within the framework of the present invention, particularly means the entire non-woven fabric surface including the embossed area and the non-embossed area.

[0066] More preferably, the aspect ratio of the embossed surface 5 of the emboss 4 is less than 3, preferably less than 2, respectively. In this regard, the aspect ratio of the embossed surface 5 means, in particular, the ratio of the maximum length or the longitudinal extension of the embossed surface 5 of one emboss 4 to the maximum width or the widthwise extension of the embossed surface 5 of the same emboss 4. Therefore, in embodiments based on these drawings in which the embossed surface 5 of the emboss 4 has a dot-shaped or circular geometry when viewed from above, the aspect ratio is equal to 1.

[0067] For the purpose, the thickness h of the nonwoven fabric 1 is from 0.15 to 0.75 mm. In embodiments based on these drawings, the thickness h of the nonwoven fabric 1 can be about 0.4 mm. At this time, the thickness h means the maximum thickness or the total thickness of the nonwoven fabric 1 in a direction transverse to, in particular perpendicular or essentially perpendicular to, the flat extension in the non-embossed area of the nonwoven fabric 1. This can be seen, in particular, in FIG. 2.

[0068] The embossing pattern 3 of the nonwoven fabric having a plurality of embosses 4 is, in particular within the framework of the present invention, characterized in that the recognizability of the embossing pattern 3 is at least clearly reduced to the human eye due to the special form of the emboss 4 and the properties of the nonwoven fabric 1, resulting in an almost invisible embossing pattern 3 consisting of the embosses 4.

[0069] Figure 3 shows the apparatus 9 of the present invention for manufacturing the nonwoven fabric 1 described above, which comprises two nonwoven webs 2, 2' made of crimped endless filaments 6. This apparatus comprises, among other things and in this embodiment, two spinning beams 10, 10', which are, preferably and in this embodiment, each designed to produce spunbond nonwoven webs 2, 2' from crimped endless filaments 6 in the form of bicomponent filaments. Further, in a preferred embodiment, there is an endless circulating deposition screen belt 11 for depositing the endless filaments 6 to form the nonwoven webs 2, 2'. The apparatus 9 has, according to the present invention, a calendar roller 7 for introducing the embossing pattern 3 into the nonwoven fabric 1. Among other things and in this embodiment, the calendar roller 7 is part of a calendar 16 composed of a calendar roller pair 7, 17. Preferably and in this embodiment, the calendar roller 7 of the calendar 16 has a complementary embossing pattern 12 consisting of embossing elements 13, each of which has a pressing surface 14 from 0.05 to 0.3 mm 2 up to. In this case, the pressing surface 14 particularly means the surface of the embossing element 13 of the calendar roller 7 provided for generating the embossing surface 5 of the embossing 4 of the nonwoven fabric 1. Preferably and in the embodiment based on Figure 3, the embossing element 13 of the calendar roller 7 is formed in the shape of a truncated cone, and the pressing surface 14 corresponds to the upper surface of this truncated cone. The other or further calendar roller 17 of the calendar 16 is, preferably and in this embodiment, formed as a smoothing roller 17 having a smooth outer surface.

[0070] According to a particularly preferred embodiment and in this example, the apparatus 9 comprises a hot air main fixing device 8, which is arranged, inter alia, in the conveying direction F of the nonwoven fabric 1, behind the calendar roller 7 or behind the calendar 16. Preferably, the hot air main fixing device 8 is configured as a hot air furnace. Expediently and in this example, furthermore, the apparatus 9 comprises two pre-fixing devices in the form of hot air pre-fixing devices 15, 15'. The hot air pre-fixing devices 15, 15' are arranged, inter alia and in this example, in the conveying direction F of the nonwoven fabric 1, in front of the calendar roller 7 or in front of the calendar 16. In particular and in the example based on FIG. 3, the hot air pre-fixing devices 15, 15' are each arranged directly behind the spinning beams 10, 10' for pre-fixing the deposited nonwoven webs 2, 2'. The first hot air pre-fixing device 15 is arranged, in the conveying direction F of the nonwoven fabric 1, preferably directly behind the first spinning beam 10, and is followed by a second spinning beam 10', behind which the second hot air pre-fixing device 15' is arranged. The hot air pre-fixing devices 15, 15' are preferably designed as hot air knives and / or hot air fields.

[0071] Within the framework of the present invention and in the embodiment based on FIG. 3, from the first spinning beam 10, first, the nonwoven web 2 is produced from the crimped endless filaments 6 and deposited on the deposition screen belt 11. Then, the nonwoven web 2 is preferably and in this embodiment pre-fixed using the hot air pre-fixing device 15. Thereafter, expediently, a second nonwoven web 2' made from the crimped endless filaments 6 is produced from the second spinning beam 10' and deposited on the first nonwoven web 2. Then, the second nonwoven web 2' or the assembly of the first nonwoven web 2 and the second nonwoven web 2' is pre-fixed using the second hot air pre-fixing device 15', and then, inter alia, peeled off from the deposition screen belt 11 and preferably fed to a calendar 16 equipped with calendar rollers 7. Using the calendar rollers 7 of the calendar 16, an embossing pattern 3 consisting of a plurality of embossings 4 is introduced into the nonwoven fabric 1, at which time the nonwoven fabric 1 is expediently fixed. Then, preferably, the fixing or main fixing of the nonwoven fabric 1 is carried out using at least one hot air main fixing device 8.

[0072] FIG. 4 shows a partial basic structure of the device 9 of the present invention for producing a nonwoven web 2 according to the spunbond process, with a spinneret or spinning beam 10 for spinning the endless filaments 6 for the spunbond nonwoven web 2 made of the endless filaments 6. The endless filaments 6 spun from the spinneret or spinning beam 10 are introduced into a cooling device 18 equipped with a cooling chamber 19. Inter alia and in this embodiment, on two opposite sides of the cooling chamber 19, air supply cabins 20, 21 arranged one above the other are arranged. From these air supply cabins 20, 21 arranged one above the other, preferably, air of different temperatures is introduced into the cooling chamber 19.

[0073] Where it is recommended and in this embodiment, in the flow direction of the filament, a stretching device 22 for stretching the endless filament 6 is arranged behind the cooling device 18. Advantageously and in this embodiment, the stretching device 22 comprises an intermediate channel 23 which connects the cooling device 18 to the stretching shaft 24 of the stretching device 22. Preferably and in this embodiment, the connecting machine consisting of the cooling device 18, the intermediate channel 23 and the stretching shaft 24 is configured as a closed connecting machine and, apart from the supply of cooling air into the cooling device 18, no further external air supply to this connecting machine takes place.

[0074] Advantageously and in this embodiment, in the flow direction of the filament, a diffuser 25 is connected to the stretching device 22 through which the endless filament 6 is guided. After passing through the diffuser 25, the endless filament 6 is deposited, inter alia and in this embodiment, on a deposition device configured as a deposition screen belt 11. The deposition screen belt 11 is preferably and in this embodiment configured as an endless circulating deposition screen belt 11. It is within the scope of the invention that the deposition screen belt 11 is air-permeable, so that suction of process air from below through the deposition screen belt is possible.

Claims

1. A nonwoven fabric having at least one nonwoven web (2) made of fibers, wherein the nonwoven fabric (1) has an embossed pattern (3), and the embossed pattern (3) is composed of a plurality of (preferably non-connected to each other) embosses (4), and each of the embosses (4) has an embossed surface (5) ranging from 0.05 to 0.3 mm ２ up to, especially 0.06 to 0.2 mm ２ up to, preferably 0.07 to 0.18 mm ２ up to, particularly preferably 0.08 to 0.15 mm ２ up to, very particularly preferably 0.09 to 0.12 mm ２ up to, a nonwoven fabric having an embossed surface (5).

2. The minimum distance d between two embossments (4) of the emboss pattern (3) is respectively from 0.6 to 2.5 mm, particularly from 0.8 to 2.0 mm, preferably from 0.9 to 1.8 mm, particularly preferably from 0.95 to 1.6 mm, and very particularly preferably from 1.0 to 1.5 mm. The non-woven fabric according to Claim 1.

3. The ratio of the total embossed surface of the emboss pattern (3) to the entire surface of the non-woven fabric (1) is from 2 to 12%, particularly from 2.5 to 8%, preferably from 3 to 6%, particularly preferably from 3.5 to 5.5%, and very particularly preferably from 4 to 5%. The non-woven fabric according to Claim 1 or 2.

4. The embossed surface (5) of the embossment (4) has at least one geometric shape selected from the group of "dot-shaped or circular, elliptical, square, rectangular, rhombic, polygonal, linear, wavy" when viewed from above. The non-woven fabric according to any one of Claims 1 to 3.

5. The aspect ratio of the embossed surface (5) of the embossment (4) is respectively less than 4, preferably less than 3, particularly preferably less than 2, for example equal to 1. The non-woven fabric according to any one of Claims 1 to 4.

6. The fibers of the at least one non-woven web (2) are formed as endless filaments (6), particularly as crimped endless filaments (6). At this time, the crimped endless filaments (6) are preferably multi-component filaments, particularly preferably bicomponent filaments. The non-woven fabric according to any one of Claims 1 to 5.

7. The multi-component filament or bicomponent filament contains a first component, and this first component consists of or consists essentially of at least one thermoplastic, particularly at least one polyolefin, especially polyethylene and / or polypropylene. And / or the multi-component filament or bicomponent filament contains a second or further different component, and this second or further different component consists of or consists essentially of at least one thermoplastic, particularly at least one polyester and / or polypropylene. The non-woven fabric according to Claim 6.

8. The endless filament (6), in particular the crimped endless filament (6), is formed as a multi-component filament or a bicomponent filament having a side-by-side configuration and / or a core-sheath configuration, in particular an eccentric core-sheath configuration, and preferably, the first component is a sheath component and the second component is a core component, the nonwoven fabric according to claim 6 or 7.

9. The non-woven fabric (1) has a basis weight of less than 200 g / m ２ 2, especially less than 150 g / m ２ 2, particularly less than 100 g / m ２ 2, preferably less than 75 g / m ２ 2, particularly preferably less than 50 g / m ２ 2, very particularly preferably less than 30 g / m ２ The non-woven fabric according to any one of claims 1 to 8, having a basis weight of less than 2.

10. The nonwoven fabric (1) has a thickness h of from 0.1 to 0.85 mm, in particular from 0.15 to 0.75 mm, preferably from 0.2 to 0.65 mm, particularly preferably from 0.25 to 0.55 mm, the nonwoven fabric according to any one of claims 1 to 9.

11. The nonwoven fabric (1) has a wear resistance of at least class 2 according to Martindale, in particular a wear resistance of class 1 according to Martindale, and / or the nonwoven fabric (1) has a maximum bending stiffness using a cantilever of at most 100 mm, in particular at most 90 mm, preferably at most 80 mm, particularly preferably at most 75 mm, very particularly preferably at most 70 mm, the nonwoven fabric according to any one of claims 1 to 10.

12. The strength of the nonwoven fabric (1) in the machine direction (MD direction) is at least 8 N / 5 cm, in particular at least 10 N / 5 cm, especially 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, the nonwoven fabric according to any one of claims 1 to 11.

13. The depth t of the emboss (4) is from 0.1 to 0.8 mm respectively, preferably from 0.15 to 0.7 mm, particularly preferably from 0.2 to 0.6 mm, very particularly preferably from 0.25 to 0.5 mm, the nonwoven fabric according to any one of claims 1 to 12.

14. The nonwoven fabric (1) is formed as a nonwoven laminate consisting of at least two nonwoven webs (2, 2') or nonwoven layers, the nonwoven fabric according to any one of claims 1 to 13.

15. The nonwoven fabric (1) is fixed using at least one calendar roller (7) for generating the embossed pattern (3) and, in particular, using at least one hot-fluid main fixing device, in particular at least one hot-air main fixing device (8), the nonwoven fabric according to any one of claims 1 to 14.

16. An apparatus for manufacturing a nonwoven fabric (1) having at least one nonwoven web (2) made of fibers, in particular for manufacturing a nonwoven fabric (1) according to any one of claims 1 to 15, the apparatus (9) comprising at least one fiber manufacturing device, in particular at least one spinning beam (10), and at least one depositing device for depositing fibers to form the nonwoven web (2), in particular at least one depositing screen belt (11), and further comprising at least one calendar roller (7) for introducing an embossing pattern (3) consisting of a plurality of embosses (4) into the nonwoven fabric (1), wherein the calendar roller (7) has, for that purpose, a complementary embossing pattern (12) consisting of embossing elements (13), and each of the embossing elements (13) has a pressing surface (14) ranging from 0.05 to 0.3 mm ２ up to, in particular from 0.06 to 0.2 mm ２ up to, preferably from 0.07 to 0.18 mm ２ up to, particularly preferably from 0.08 to 0.15 mm ２ up to, and very particularly preferably from 0.09 to 0.12 mm ２ The apparatus having a pressing surface (14).

17. The device (9) comprises at least one hot-fluid main fixing device, in particular at least one hot-air main fixing device (8), wherein the hot-fluid main fixing device is arranged, in particular, behind the calendar roller (7) in the conveying direction F of the nonwoven fabric (1), the device according to claim 16.

18. The device comprises at least one pre-fixing device, in particular at least one hot-fluid pre-fixing device, preferably at least one hot-air pre-fixing device (15), wherein the pre-fixing device is arranged, particularly preferably, in front of the calendar roller (7) in the conveying direction F of the nonwoven fabric (1) and, very particularly preferably, is installed behind or immediately behind the at least one fiber production device or the at least one spinning beam (10), the device according to claim 16 or 17.

19. A method for manufacturing a nonwoven fabric (1) having at least one nonwoven web (2) made of fibers, in particular for manufacturing the nonwoven fabric (1) according to any one of claims 1 to 15 and / or using an apparatus (9) according to any one of claims 16 to 18, comprising manufacturing the fibers using at least one fiber manufacturing device, in particular at least one spinning beam (10), depositing the fibers onto at least one deposition device, in particular at least one deposition screen belt (11) to form a nonwoven web (2), fixing the nonwoven web (2) or the nonwoven fabric (1) using at least one calendar roller (7), and introducing an embossing pattern (3) consisting of a plurality of embossings (4) into the nonwoven fabric (1) using the at least one calendar roller (7), wherein each of the embossings (4) has an embossing surface (5) of from 0.05 to 0.3 mm ２ up to, in particular from 0.06 to 0.2 mm ２ up to, preferably from 0.07 to 0.18 mm ２ up to, particularly preferably from 0.08 to 0.15 mm ２ up to, very particularly preferably from 0.09 to 0.12 mm ２ up to, a method.

20. The nonwoven fabric (1) is fixed, in particular main-fixed, using at least one hot-fluid main fixing device, in particular at least one hot-air main fixing device (8) (in particular following fixing using the at least one calendar roller (7)), the method according to claim 19.

21. The nonwoven fabric (1) is first pre-fixed using at least one pre-fixing device, in particular at least one hot-fluid pre-fixing device, in particular using at least one hot-air pre-fixing device (15) after deposition on the deposition device, in particular on the deposition screen belt (11), and is then, in particular, fixed using the at least one calendar roller (7) and is then, preferably, fixed using a hot-fluid main fixing device or a hot-air main fixing device (8), in particular main-fixed, the method according to claim 19 or 20.

22. The surface temperature of the at least one calendar roller (7) is higher than the temperature of the heat transfer fluid of the at least one heat transfer fluid type main fixing device, in particular 1 °C to 15 °C higher, preferably 1 °C to 5 °C higher, or lower than the temperature of the heat transfer fluid of the at least one heat transfer fluid type main fixing device, or the same as or essentially the same as the temperature of the heat transfer fluid of the at least one heat transfer fluid type main fixing device, the method according to any one of claims 19 to 21.

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