Paper machine clothing

Abstract

A paper machine clothing, in particular a seam felt for use in the press section of a machine for producing a fibrous web, wherein the paper machine clothing (1) comprises at least one basic structure and at least one layer of staple fibers or short fibers arranged on the basic structure, the at least one short fiber layer being arranged on the side facing the fibrous web and / or on the side facing the machine, wherein the paper machine clothing comprises at least one seam region in which seam loops are connected to one another by at least one plug wire to form a loop of the paper machine clothing, and wherein the at least one short fiber layer is separated in the region of the seam region by at least one cut to form a seam cover and a seam wedge, wherein at least one connecting element (20) is inserted between the seam cover and the seam wedge, wherein the at least one connecting element is connected to the short fiber material of the seam cover and / or the seam wedge in a fitting manner, in particular welded. A method for using such a paper machine clothing.

Description

[0001] The invention relates to a paper machine clothing, in particular a seaming felt for use in the press section of a machine for producing a fibrous web, and a method for using such a paper machine clothing.

[0002] When it comes to paper machine clothing, especially press felts, there has been a trend for some time towards seamed paper machine clothing, away from endless paper machine clothing. The advantage for users is that these seamed paper machine clothings are much easier to install in the machine. Furthermore, new systems can save considerable construction effort if no precautions for tensioning endless clothing are required.

[0003] In particular, the seam felt is produced here with a slug seam that connects the ends of the felt in the area of ​​its base fabric. A nonwoven layer is applied and sewn onto this base fabric, which is thus continuous or endless, at least on the paper side and often even on the running side. Since this is advantageous from a production perspective, the nonwoven layer is also sewn here with a slug seam.

[0004] In order to load the felt into the paper machine, the felt seams must be opened again. This is easily achieved in the base fabric by removing the insert threads. However, the nonwoven layers that are sewn onto the seams must be untied.

[0005] To this end, the paper-side nonwoven layer of one felt end is separated from the paper-side nonwoven layer of the other felt end in the area of ​​the inserted thread by a cut. This cut is introduced into the still closed nonwoven fabric through the seam after sewing. The cut can be designed vertically, but it is preferably designed slightly obliquely, i.e., preferably with a deviation of 5-30° from the vertical.

[0006] After the felt has been inserted, the quilted seam is closed again with quilted threads, for example in the form of fiber bundles. Although the nonwoven layers of the two felt ends touch or overlap, the properties of the felt in this seam area, such as its porosity, differ from those of the rest of the felt.

[0007] To overcome this drawback, several possible approaches to optimizing the seam area are known from the prior art. For example, WO 02 / 35000 A1 proposes introducing strips of flow-retarding material into the seam area of ​​a paper machine clothing. Alternatively, EP 1 918 453 A1 and WO 2015 / 024718 describe introducing liquid materials or small particles into the seam area.

[0008] All of these optimizations of the seam area serve to modify the flow properties in this region, but they cannot overcome the fundamental disadvantage that the nonwoven covering is permanently weakened at this location due to the cuts.

[0009] Thus, for example, due to the cuts and, in particular, the oblique cuts, the fiber anchorage in the seam region of the felt surface is less than in the remaining areas of the felt surface. Due to the presence of the seam loops and the fact that the seam loops must be substantially free of fiber material in order to allow the insertion of the plug wire, the geometry of the felt seams is generally not conducive to fiber anchorage, so that, although it is possible to improve the fiber anchorage, this possibility is limited.

[0010] Furthermore, the cuts are susceptible to damage because there is no fiber anchoring for the fibers on the other side of the nonwoven cover directly in the cut area. Experience has shown that felt wear is more severe in the seam area, and damaged seam areas often cause marks in the paper or even sheet breaks during papermaking. Consequently, cuts are a factor in shorter felt run times, even though the felt outside the seam is still sufficient for many days of continued use.

[0011] Furthermore, during the stretching of the felt there is the risk that the gap above the seam will widen and thus be subjected to the intensified effect of abrasive contact elements or water jet nozzles in the paper machine.

[0012] The technical problem to be solved by the present invention is to overcome the problems of the prior art.

[0013] In particular, the object of the present invention is to propose a paper machine clothing which is more wear-resistant than known paper machine clothings.

[0014] Furthermore, the invention is based on the object of proposing a paper machine clothing whose seams are less susceptible to marking than known seamed paper machine clothings.

[0015] In particular, it is proposed that the advantageous effects be achieved with little or no change in the permeability of the seam region.

[0016] Furthermore, a method for using such a paper machine clothing is to be proposed.

[0017] The aforementioned technical problem is completely solved by a paper machine clothing and a method for using a paper machine clothing.

[0018] Further advantageous features of the embodiment according to the invention are stated in the dependent claims.

[0019] The above-mentioned technical problem is solved with respect to a paper machine clothing by a seam felt, in particular for use in the press section of a machine for producing a fibrous web, wherein the paper machine clothing comprises at least one base structure and at least one layer of staple fibers or short fibers arranged on the base structure, the at least one short fiber layer being arranged on the side facing the fibrous web and / or on the side facing the machine, wherein the paper machine clothing comprises at least one seam region, in which seam loops are connected to one another by at least one plug wire to form a loop of the paper machine clothing, and wherein the at least one short fiber layer is separated in the region of the seam region by at least one cut to form a seam cover and a seam wedge. According to the invention, at least one connecting element is inserted between the seam cover and the seam wedge, wherein the at least one connecting element is connected to the short fiber material of the seam cover and / or the seam wedge in a fitting manner, in particular welded.

[0020] In press felts, it is common to have at least one staple fiber layer on the side facing the fibrous web; it can also be provided that the staple fibers are on the running side facing the machine.

[0021] The terms "seam cover" and "seam wedge" are used here to describe the use of oblique cuts. In the case of paper machine clothings with vertical cuts, which are also explicitly included in the present invention, these two terms are used to designate one or the other cut end of the nonwoven layer.

[0022] In a particularly preferred embodiment, the connection of at least one connecting element to the staple fibers of the seam cover and / or seam wedge can be accomplished by near-infrared transmission welding. For this purpose, it is particularly advantageous if at least one connecting element comprises or consists of a polymer material that at least predominantly absorbs light having a wavelength in the near-infrared range between 780 nm and 3 μm, preferably between 780 nm and 1300 nm. This should be understood as meaning that the polymer material does not necessarily need to absorb in the entire near-infrared range between 780 nm and 1300 nm (or 3000 nm). It is sufficient if the polymer material absorbs predominantly in at least one or more subranges of this near-infrared range. Welding can then be performed using light having a wavelength originating from this subrange.

[0023] The staple fibers of the nonwoven layer are usually made of polyamide, which is largely transparent to light from this wavelength range.

[0024] Therefore, a joint region with at least one connecting element can be irradiated with light of a corresponding wavelength under a certain joining pressure. A laser or other suitable light source can be used as the light source. The connecting element absorbs the light, thereby heating and completely or partially melting, thereby forming a materially bonded connection between the connecting element and the staple fibers in contact therewith. The staple fibers are heated essentially only by contact with the connecting element. The staple fibers of the nonwoven layer thus remain virtually unchanged during the joining process. Consequently, the joining process does not result in any significant changes in the permeability or porosity of the joint region.

[0025] This positive property occurs automatically in transmission welding, whereas in equally possible connections, for example by gluing or ultrasonic welding, the joining process must be controlled very precisely.

[0026] The absorption properties of the connecting element can be achieved, for example, by adding an absorption additive to the connecting element. Carbon black is suitable for this, for example. However, absorbers with other colors and even transparent ones are also available on the market, for example from Clearweld (www.clearweld.com).

[0027] These additives can either be added to the polymer material or applied as a coating to the connecting element.

[0028] The absorption additive makes it possible to manufacture the connecting element from the same polymer material as the staple fibers of the nonwoven layer, typically polyamide, and still use the advantageous technology of near-infrared transmission welding. Due to the material homogeneity, a particularly good and durable welded connection can be produced.

[0029] It is particularly advantageous if, after joining, i.e., in particular welding, the at least one connecting element is materially bonded to both the staple fibers of the seam cover and the seam wedge. This firmly connects the two cut edges to one another, improving fiber anchoring and making the seam more wear-resistant. This also prevents the nonwoven layer from stretching under tensile load, thereby reducing the tendency of the seam to mark.

[0030] Tests carried out by the applicant to improve the joint have surprisingly shown that the use of connecting elements leads to significantly better results than by a simple connection, for example welding two cut edges to one another.

[0031] This means that between two cut edges without connecting elements, there are only contact points, and thus connection points, when short fibers from one edge accidentally touch short fibers from the other edge. Therefore, the joint connection that can be achieved with this is usually only very weak.

[0032] The connecting element inserted into the seam in the paper machine clothing proposed here acts as a bridge between the contact points of the two edges. Each of the two edges has multiple contact points with the connecting element, and the probability of a firmly bonded connection is therefore significantly higher than if no connecting element is used.

[0033] The user has greater freedom in selecting a connecting element in the seam, or even multiple connecting elements if necessary, as will be described in detail below. The connecting elements can be selected in such a way that the permeability of the seam is hardly affected, but a secure connection is still achieved.

[0034] Conversely, if precisely this property of the joint is to be influenced, this can also be achieved by selecting other connecting elements.

[0035] The paper machine clothing according to aspects of the present concept therefore also allows the user a great deal of flexibility in the design of the seam area.

[0036] A method for using a paper machine clothing according to the invention can be to first draw the paper machine clothing into the press section of a machine for producing a fibrous web and then loop it by closing the insertion seam. This process ends here with known seamed clothings. With the paper machine clothing proposed here, it is possible to subsequently connect, in particular weld, the at least one connecting element to the staple fibers of the seam cover and / or seam wedge.

[0037] This method can be designed in different variations.

[0038] In a variant, the at least one connecting element is inserted between the seam cover and the seam wedge only after the paper machine clothing has been drawn into the machine, in particular after looping by thread insertion, and is then integrally connected.

[0039] In another embodiment, the at least one connecting element can be temporarily connected to the seam wedge or seam cover before the paper machine clothing is installed in the machine. "Temporarily" means that, in this embodiment, the connecting element is connected to the seam cover or seam wedge before the paper machine clothing is installed. However, this connection is not yet a materially bonded connection that will be established later. This temporary connection can be, for example, a form-fitting connection (such as a slight seam or dot-stitching) or an adhesive bond, in particular using a water-soluble adhesive, which can be washed out later during machine operation. This has the advantage that the connecting element or elements are positioned correctly, as the personnel who install the paper machine clothing generally do not have the necessary knowledge and technical expertise for this purpose.

[0040] Alternatively, in another variant, the at least one connecting element can be integrally connected to the seam wedge or seam cover before the paper machine clothing is installed in the machine. Advantageously, this permanent joint virtually eliminates the possibility of the connecting element slipping out during installation. On the other hand, this method requires two joining processes, such as welding, which can have negative consequences. Depending on the application, advantages or disadvantages may prevail.

[0041] In an advantageous embodiment, it can be provided that at least one connecting element is designed as a linear or ribbon-shaped connecting element.

[0042] Linear refers to connecting elements that are similar in thickness and width, but significantly longer.

[0043] In the case of a thread-like design, the connecting element can be designed in particular as a monofilament, a multifilament bundle or a twisted wire.

[0044] The term "ribbon-shaped" refers to a connecting element whose width is significantly greater than its thickness and whose length is significantly greater than its width.

[0045] In the case of a strip-shaped embodiment, the at least one connecting element can be designed in particular as a textile strip, a nonwoven, a film or a foam.

[0046] The textile tape can be, for example, a woven, knitted or braided fabric.

[0047] The nonwoven can be, for example, a so-called meltblown nonwoven or a meltblown nonwoven.

[0048] Preferably, the linear or ribbon-shaped connecting element may have a length of 10 mm or more, in particular greater than 20 mm in the longitudinal direction. A greater length of the connecting element improves the above-mentioned bridging effect of the connecting element.

[0049] It is generally advantageous if one or more connecting elements are distributed over substantially the entire length of the cutout (in the CD direction).

[0050] On the one hand, this can be achieved in that one or more connecting elements extend over the majority of the length of the cutout.

[0051] When using a plurality of connecting elements, all connecting elements can be identical. Alternatively, it is also conceivable that connecting elements of different types are inserted into the incision.

[0052] In particular, it can be provided that the thread-like or strip-like connecting element extends in the cross-machine direction over at least half the width, preferably over the entire width, of the paper machine clothing. To avoid confusion, it should be clarified again that in this case the longitudinal or length direction of the connecting element extends essentially along the cut and thus in the cross-machine direction (CD) of the paper machine clothing.

[0053] Since modern paper machine clothings can have a width of 10 m or more, in this case the length of the linear or ribbon-like connecting elements is significantly greater than the aforementioned 10 mm or 20 mm. Therefore, the length of the connecting elements is more likely to be in the range of several meters (e.g., greater than 2 m, or even greater than 5 m).

[0054] Alternatively or additionally, a plurality of connecting elements can also be provided, which are designed, for example, in the form of short fibers which are introduced into the cutouts.

[0055] Advantageously, these fibers can be designed such that they at least predominantly absorb light having a wavelength in the near infrared range of 780 [nm] to 3 [μm].

[0056] It is particularly preferred that the fibers be designed such that they at least predominantly absorb light having a wavelength in the near infrared range of 780 [nm] to 1300 [μm], since in the range above 1300 [nm] there is an increased risk that short fibers or the material of the underlying structure absorb this light to a certain extent, which is undesirable in many cases.

[0057] Further advantageous features of the invention will be explained with reference to the accompanying drawings based on exemplary embodiments. These features can be advantageously implemented not only in the combinations shown, but also individually in combination with one another.

[0058] Figure 1 shows a detail of a paper machine clothing according to one aspect of the invention,

[0059] Figure 2 shows a detail of a paper machine clothing according to another aspect of the invention,

[0060] Figure 3 shows a detail of a paper machine clothing according to another aspect of the invention,

[0061] Figure 4 shows a detail of a paper machine clothing according to another aspect of the invention,

[0062] The accompanying drawings are described in detail below.

[0063] Figure 1 A detail of a paper machine clothing 1 according to one aspect of the present invention is shown. In particular, the seam area 2 is also shown here. The paper machine clothing comprises a base structure 3, which is designed as a base fabric 3. Each end of the base structure has a seam loop 4. Such a seam loop 4 can be formed, for example, by folding and stacking the base structure 3. The seam loop 4 is formed by longitudinal threads 6 (MD threads) of the base fabric 3. Individual transverse threads (CD threads) of the base fabric can also be removed to form the seam loop 4. The paper machine clothing 1 is looped by overlapping two seam loops 4 and connecting them by inserting a plug thread 5. The plug thread 5 can be a single thread. Figure 1 The paper machine clothing 1 in FIG. 1 shows as an alternative a plug wire 5 formed by a plurality of wires. Otherwise, the skilled person is completely free to select a suitable plug wire 5. The advantages of the invention can be achieved independently of the choice of the plug wire 5.

[0064] The paper machine clothing 1 also comprises two staple fiber layers 8, 8b. The staple fiber layer 8b on the running side can also be omitted if necessary. The staple fiber layer 8 on the paper side is applied continuously to the base structure 3, in particular sewn to the base structure 3. To enable the paper machine clothing 1 to be installed in the machine, the staple fiber layer 8 is opened at the seam by an incision 9. In principle, the incision 9 can be made vertically. However, if Figure 1 As shown, the cutouts 9 are usually made obliquely, i.e. at an angle to the vertical. This angle is advantageously between 5° and 30°. This creates a seam cover 10 and a seam wedge 11. The seam cover 10 overlaps the seam wedge 11 in the closed paper machine clothing 1.

[0065] In the incision according to Figure 1 In the design of the paper machine clothing 1, for example, three connecting elements 20 are inserted. These connecting elements 20 are each designed as a thread that extends across the entire transverse direction of the paper machine clothing 1 or of the cutout 9. For example, monofilaments, multifilament bundles, or twisted threads can be used as threads 20. More or fewer threads than the three threads 20 shown can also be used.

[0066] The connecting elements 20 can be distributed uniformly over the height of the cutout 9. Alternatively, a non-uniform distribution can also be advantageous, for example more connecting elements 20 being arranged near the base structure 3 than towards the paper side, or vice versa.

[0067] When a plurality of connecting elements 20 are used, all connecting elements 20 can be identical. Alternatively, it is also conceivable that different types of connecting elements 20 are inserted into the cutout 9 .

[0068] The thread 20 is materially bonded to both the seam cover 10 and the seam wedge 11. This material-to-material connection can be achieved, for example, by welding. Therefore, it is particularly advantageous if the connecting element 20, in this case the thread 20, consists of a polymer that at least largely absorbs light in the suitable near-infrared wavelength range of 780 nm to 1300 nm. For example, the material forming the press felt in the seam region (typically PA6 or PA66) is largely transparent in this wavelength range. Therefore, the welded connection can be produced very simply by near-infrared transmission welding. It is particularly advantageous to use the same polymer for the connecting element 20 as for the staple fibers 8 (e.g., PA6 or PA66), which has favorable absorption properties only due to the addition of an absorption additive. This material equality of the connecting element 20 and the staple fibers 8 allows for particularly durable welding. Alternatively, suitable thermoplastics such as copolyamide, PEBA, or thermoplastic polyurethane, which are highly compatible with the material of the staple fiber layers 8, 8b, can also be used for the connecting element 20.

[0069] like Figure 1 As shown, the staple fiber layer 8b on the running side has a larger gap in the seam area 2. This makes it easier to insert the plugging thread 5, for example, and has only minimal, if any, negative impact on the quality of the produced paper. However, within the scope of the present invention, it is also conceivable to treat the staple fiber layer 8b on this side in the same manner as on the paper side. That is, on the running side, the staple fiber layer 8b can also be connected at the seam by inserting the connecting element 20.

[0070] Figure 2 The paper machine clothing 1 shown in Figure 1 The designs differ only in the choice of connecting element 20. Figure 2 A single, strip-shaped connecting element 20 is provided here. The strip-shaped connecting element 20 can be, for example, a nonwoven, a foam, a membrane or even a textile strip, which can in particular extend over the entire width of the felt 1 or the cutout 9. In the case of the strip-shaped connecting element 20, in particular in the case of the membrane 20, it is advantageous to select a very thin membrane that has no or only a slight influence on the permeability of the seam area 20. For example, the membrane can be cut so that its length corresponds to the width of the felt and its width corresponds to the height of the cutout 9. The dewatering of the felt 1 in the depth direction is thus hardly affected by the small membrane thickness, but the anchoring of the nonwoven is improved by the membrane. Preferably, a membrane or sheet with a thickness of up to 50 μm is selected. Particularly advantageous are permeable or perforated membranes. The membrane or sheet can be unoriented or uniaxially or biaxially oriented.

[0071] It can also be provided that all or most of the membrane or sheet is inserted into the cutout 9 and that the permeability of the membrane is produced only by dissolution of the closed membrane structure by the welding process (for example by melting).

[0072] Figure 3 1 shows a paper machine clothing 1 in which the connecting element 20 is realized by flocking the seam wedge 11. Alternatively or additionally, the seam cover 10 can also be flocked. The flock fibers 20 are advantageously designed to absorb in the near-infrared wavelength range. The flocking creates a connection between the connecting element and the seam wedge 11. However, this connection is usually temporary. If Figure 3 The cutout 9 , which is still shown open, can be closed, if necessary, by applying a joining pressure, and a material-fit connection to the seam wedge 11 and / or the seam cover 10 can be achieved by a welding process, preferably by transmission welding.

[0073] at last Figure 4 An embodiment is shown in which short fibers that absorb in the near-infrared wavelength range are specifically introduced as connecting elements 20 into the staple fiber layer 8 in the area of ​​the cutout 9. The material-bonding connection can again be achieved by welding. The short absorbent fibers can be introduced during the production of the nonwoven layer 8. Alternatively, they can be added subsequently, i.e., after the cutout 9 has been created, to the seam wedge 11 and / or the seam cover 10. Advantageously, these short absorbent fibers can be distributed in the seam cover 10 and / or the seam wedge 11 over the entire width of the paper machine clothing 1 and in its longitudinal direction over a range of 1 mm to 20 mm, in particular over a range of 2 mm to 10 mm. The short absorbent fibers can also be provided over a larger area of ​​the staple fiber layer 8, 8b. In particular, provision can also be made for the short absorbent fibers to be distributed over the entire staple fiber layer 8, in particular over the entire staple fiber layer on the paper side.

[0074] The drawings shown are intended to illustrate several possible embodiments of the invention. However, the invention is not limited to these embodiments.

[0075] List of reference numerals:

[0076] 1Paper machine clothing

[0077] 2 seam area

[0078] 3 Infrastructure

[0079] 4 seam loops

[0080] 5 plug wire

[0081] 6 Yarns in the machine direction (MD)

[0082] 7 Yarns in the cross direction (CD)

[0083] 8, 8b short fiber layer

[0084] 9 incisions

[0085] 10 seam covers

[0086] 11 seam wedge

[0087] 20 connecting elements

Claims

1. A paper machine clothing (1) for use in the press section of a machine for producing a fibrous web, wherein: The paper machine clothing (1) comprises at least one basic structure (3) and at least one staple fiber layer (8) arranged on the basic structure (3), the at least one staple fiber layer (8) being arranged on the side facing the fiber web and / or on the side facing the machine, wherein the paper machine clothing (1) comprises at least one seam area (2), in which seam loops (4) are connected to one another by at least one plug thread (5) to loop the paper machine clothing (1), and wherein the at least one staple fiber layer (8) is passed through in the region of the seam area (2). The invention relates to a method for manufacturing a multifunctional composite material comprising: separating the multifunctional composite material and the multifunctional composite material through at least one incision (9) to form a seam cover (10) and a seam wedge (11), characterized in that at least one connecting element (20) is inserted between the seam cover (10) and the seam wedge (11), wherein the at least one connecting element (20) is welded to the short fibers of the seam cover (10) and / or the seam wedge (11), and the at least one connecting element comprises a polymer material that absorbs light having a wavelength in the near infrared range of 780 [nm] to 3 [μm] at least to a large extent.

2. The paper machine clothing according to claim 1, characterized in that The at least one connecting element is designed as a linear or ribbon-shaped connecting element.

3. The paper machine clothing according to claim 2, characterized in that The linear or ribbon-shaped connecting element has a length of 10 mm or more in the longitudinal direction.

4. The paper machine clothing according to any one of claims 1 to 3, characterized in that A plurality of connecting elements are inserted between the seam cover (10) and the seam wedge (11), and the plurality of connecting elements are cooperatively connected to the short fiber material of the seam cover (10) and / or the seam wedge (11).

5. The paper machine clothing according to any one of claims 1 to 3, characterized in that The at least one connecting element is of linear design and extends in the cross-machine direction over at least half the width of the paper machine clothing.

6. The paper machine clothing according to any one of claims 1 to 3, characterized in that The at least one connecting element is designed in the form of a strip and extends in the cross-machine direction over at least half the width of the paper machine clothing.

7. The paper machine clothing according to claim 1, characterized in that The paper machine clothing (1) is a seaming felt.

8. The paper machine clothing according to claim 1, characterized in that The polymer material absorbs light having a wavelength in the near infrared range between 780 [nm] and 1300 [nm] at least to a large extent.

9. The paper machine clothing according to claim 3, characterized in that The linear or ribbon-shaped connecting element has a length in the longitudinal direction of greater than 20 mm.

10. The paper machine clothing according to claim 3, characterized in that The linear or ribbon-shaped connecting element has a length of more than 2 m in the longitudinal direction.

11. The paper machine clothing according to claim 4, characterized in that The plurality of connecting elements are welded to the short fiber material of the seam cover (10) and / or the seam wedge (11).

12. The paper machine clothing according to claim 5, characterized in that The at least one connecting element is designed as a monofilament, a multifilament bundle or a twisted thread.

13. The paper machine clothing according to claim 5, characterized in that The thread-shaped connecting element extends in the cross-machine direction over the entire width of the paper machine clothing.

14. The paper machine clothing according to claim 6, characterized in that The at least one connecting element is designed in a strip-like manner as a textile tape, a nonwoven fabric, a film or a foam.

15. The paper machine clothing according to claim 6, characterized in that The belt-shaped connecting element extends in the cross-machine direction over the entire width of the paper machine clothing.

16. A method for using a paper machine clothing (1) according to one of claims 1 to 15, wherein: A paper machine clothing (1) is first inserted into the press section of a machine for producing a fibrous web, and then looped by closing the insertion seam, wherein the at least one connecting element (20) is then welded to the short fibers of the seam cover (10) and / or the seam wedge (11), and the at least one connecting element is designed to be absorptive for light in the near-infrared wavelength range between 780 [nm] and 3 [μm], and the connection is completed by near-infrared transmission welding.

17. The method according to claim 16, wherein The at least one connecting element is designed to be absorptive for light in the near-infrared wavelength range between 780 nm and 1300 nm.

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