Abstract
A covering for a machine for producing or processing a fibrous web, in particular a paper or tissue web. The covering includes a basic covering which has a web-contacting upper side and an underside, and a plurality of polymer elements. The polymer elements are welded onto the upper side and at least some of the polymer elements are in the form of yarn-shaped and/or tape-shaped polymer elements.
Claims
1-15. (canceled)
16. A clothing for a machine for producing or processing a fibrous material web, the clothing comprising: a base clothing having a web-contacting upper side and a bottom side opposite said upper side; and a plurality of polymer elements welded onto said upper side; at least some said polymer elements being selected from the group consisting of yarn-shaped polymer elements and tape-shaped polymer elements having a width of less than 15 mm.
17. The clothing according to claim 16, wherein said polymer elements are drawn uniaxially or biaxially.
18. The clothing according to claim 16, wherein said yarn-shaped polymer elements have a diameter of more than 100 μm.
19. The clothing according to claim 18, wherein the diameter of said yarn-shaped polymer elements is between 200 μm and 500 μm.
20. The clothing according to claim 16, wherein said polymer elements are arranged in a machine direction of the clothing or the polymer elements deviate from the machine direction by less than 15°.
21. The clothing according to claim 20, wherein the clothing is a continuous clothing or the clothing is made continuous and some or all of said polymer elements are arranged spirally on the continuous clothing.
22. The clothing according to claim 16, wherein all of said polymer elements are of the same kind.
23. The clothing according to claim 16, wherein said polymer elements are composed of solid material and are not hollow on an inside thereof.
24. The clothing according to claim 16, wherein said base clothing has a batt layer providing said web-contacting upper side of said base clothing.
25. The clothing according to claim 16, wherein said base clothing is transparent to light within a near-infrared range between 780 nm and 1300 nm, and said polymer elements are absorbent for light of a wavelength within the near-infrared range between 780 nm and 1300 nm.
26. The clothing according to claim 16, further comprising a medium disposed between said upper side of said base clothing and said polymer elements, said medium being configured to completely or largely absorb light of a wavelength within a near-infrared range between 780 nm and 1300 nm.
27. The clothing according to claim 16, wherein at least some of said polymer elements consist of a material having a hardness of 40 Shore D or more.
28. The clothing according to claim 27, wherein all of said polymer elements consist of a material having a hardness of 50 Shore D or more.
29. The clothing according to claim 16, wherein at least some of said polymer elements have a circular cross-section.
30. The clothing according to claim 16, wherein at least some of said polymer elements have a cross-section which is noncircular.
31. The clothing according to claim 16, wherein all of said polymer elements have a circular cross-section or all of said polymer elements have a noncircular cross-section.
32. The clothing according to claim 16, wherein a distance between two mutually adjacent polymer elements is at least 1 mm.
33. The clothing according to claim 16, wherein the distance between two mutually adjacent polymer elements lies between 2 and 5 mm.
34. The clothing according to claim 16, wherein at least some of said polymer elements are formed of a polyurethane.
35. The clothing according to claim 34, wherein the polyurethane is a thermoplastic polyurethane.
Description
[0069] Exemplary embodiments will be used to elucidate further advantageous characteristics of the invention with reference to the drawings. The features mentioned can not only be advantageously implemented in the combination shown, but can also be individually combined with one another. The figures show in detail:
[0070] FIG. 1 shows a clothing according to one aspect of the invention
[0071] FIG. 2 shows a clothing according to a further aspect of the invention
[0072] FIG. 3 shows an upper side of a clothing according to a further aspect of the invention
[0073] FIG. 4 shows a section through a clothing according to a further aspect of the invention
[0074] The figures are described in more detail in what follows.
[0075] FIG. 1 shows a clothing 1 for a machine for producing or processing a fibrous material web, especially a paper or tissue web. The clothing 1 comprises a base clothing 2 which has a web-contacting upper side 2a and a bottom side. Here, the base clothing 2 has a base structure 4, for example in the form of a base woven fabric 4, and a batt layer 5. The batt layer 5 provides the paper-contacting upper side 2a, whereas the base structure 4 provides the bottom side. In alternative embodiments, it is also additionally possible to provide a further batt layer underneath the base structure, which then forms the bottom side of the clothing 1. The batt layer 5 can be connected to the base structure 4 by needling, for example. Depicted on the upper side 2a are a plurality of polymer elements 3, 3a, 3b, which are welded onto the upper side 2a. FIG. 1 depicts various types of polymer elements 3, 3a, 3b in order to indicate the variety of options possible in the context of the present invention. In advantageous embodiments of the clothing 1, it is, however, also possible to provide only one or two types of polymer elements 3, 3a, 3b. The polymer elements 3 and 3b are in the form of yarn-shaped or tape-shaped polymer elements. At the same time, they can be polymer elements 3 oriented in the machine direction (MD), polymer elements 3a oriented in the transverse direction, or else polymer elements oriented in other directions. 3, 3a can. The yarn-shaped or tape-shaped polymer elements 3, 3a can be drawn polymer elements 3, 3a. They can then serve not only for structuring and dewatering of the web, but also for increasing the strength of the clothing 1. It is, however, also possible to provide undrawn polymer elements 3, 3a, 3b, which are, for example, applied directly to the upper side 2a of the clothing 1 or the batt layer 5 by extrusion. The polymer elements 3b are intended to show that the polymer elements 3, 3a, 3b can also be in the form of purely decorative structuring elements, the purpose of which is almost exclusively that of structuring the fibrous material web. Such polymer elements 3b can, for example, be in the form of figurative motifs, letters or company logos. Said polymer elements 3b can then, for example, be extruded or printed onto the surface 2a.
[0076] Moreover, all the polymer elements 3, 3a, 3b are welded onto the upper side 2a.
[0077] In the case of the clothing 1 shown in FIG. 2, the base clothing 2 consists of a base structure 4 in the form of a woven fabric 4, yarn-shaped polymer elements 3 drawn in their longitudinal direction are welded onto the upper side 4. The yarn-shaped polymer elements 3 are essentially arranged in the machine direction (MD) of the clothing 3. In particular, the polymer elements 3 can also be arranged spirally. In this case, the polymer elements 3 shown in FIG. 2 each represent the various windings of an individual polymer element 3. Advantageously, said polymer elements 3 are distributed uniformly over the width of the clothing 1 and also extend substantially over the entire length thereof. Such drawn polymer elements 3 perform two different functions in the clothing at the same time. Firstly, they serve for structuring of the fibrous material web and support dewatering. At the same time, they increase the strength, especially the tensile strength, of the clothing 1. To this end, it is again very advantageous if—as is possible especially through the process of transmission welding—both a strong joint connection between the polymer elements 3 and the upper side 2a of the base clothing 2 is produced, and the polymer elements 3 are nevertheless not structurally damaged or only insignificantly structurally damaged. In FIG. 2, the base structure 4 is in the form of a base woven fabric 4. Since the drawn, yarn-shaped polymer elements 3 already provide a large share of the tensile strength of the clothing 1, thinner woven fabrics can be used compared to conventional clothings 1. As an alternative to base woven fabrics 4, nonwoven base structures 4 can also be used in clothings 1 like that in FIG. 2. For example, base structures 4 composed of one or more polymer films can be used.
[0078] FIG. 3 shows an upper side 2a of a clothing 1 such as the one depicted in FIG. 1. The paper-contacting upper side 2a is provided by a batt layer 5. Polymer elements 3 are welded onto said batt layer 5 by means of transmission welding. Here, the polymer elements 3 are drawn yarns; alternatively, they could, however, also be undrawn yarn-shaped polymer elements 3, which are, for example, applied directly to the surface 2a by extrusion. The fibers of the batt layer 5 are composed of a polymer which is completely or largely transparent to light within the near infrared range between 780 [nm] and 1300 [nm]. Polyamides have this property. The polymer elements 3 in FIG. 3 are colored by addition of an additive—carbon black here—and they absorb the relevant light as a result. The polymer elements 3 can then optionally also consist of the same material as the batt fibers, which allows a very strong welded connection.
[0079] The yarn-shaped polymer elements 3 in FIG. 2 can be arranged in almost any way, for example in the machine direction (MD), in the transverse direction (CD) or diagonally. This opens up high degrees of freedom for the structuring of the paper web. The distance between two adjacent polymer elements 3 is advantageously at least 1 mm, preferably between 1.5 mm and 10 mm, particularly preferably between 2 and 5 mm. The polymer elements 3 in FIG. 3 have distances ranging between 1.5 mm and 1.8 mm.
[0080] FIG. 4 depicts a section in relation to the clothing 1 from FIG. 3, showing only the batt layer 5 without the underlying base structure 4. Here, the polymer elements 3 have a diameter of 300 μm. Preferably, such polymer elements 3 have diameters between 200 μm and 500 μm. As can be clearly seen in FIG. 4, the structure of the yarn-shaped polymer elements is virtually unchanged even after welding. Although they are pressed somewhat into the batt layer 5 owing to the joining pressure during welding, the polymer elements 3 still distinctly protrude beyond the surface 2a, and so they allow reliable structuring of the paper web, tissue web or other fibrous material web.
LIST OF REFERENCE SIGNS
[0081] 1 Clothing [0082] 2 Base clothing [0083] 2a Upper side [0084] 3, 3a, 3b Polymer elements, structuring elements [0085] 4 Base structure [0086] 5 Batt layer
