Sheet material, method for producing a sheet material

Abstract

The invention relates to a yarn having a core and a sheath surrounding the core, the core containing a polyether ketone and the sheath surrounding the core containing a perfluoroalkoxy polymer. The invention also relates to a sheet material, the use of the yarn for producing the sheet material, a method for producing the yarn and a method for producing the sheet material.

Description

SCOPE OF APPLICATION AND STATE OF THE ART

[0001] The invention relates to a planar structure and a method for producing a planar structure.

[0002] Conveyor belts are widely used today for transporting products. These conveyor belts can have a textile structure. For example, WO 2013 / 004474 A1 discloses a fabric based on spiral threads and interlocking threads, which is suitable, among other things, for the production of conveyor belts.

[0003] A common problem associated with conveyor belts is that the products being transported, for example when passing through a heating zone, can stick to the conveyor belts and / or the functionality of the conveyor belts can be impaired over time due to a lack of or insufficient temperature resistance. TASK AND SOLUTION

[0004] The present invention is therefore based on the objective of providing a planar structure comprising a thread which avoids disadvantages known from the prior art, particularly in connection with conveyor belts. Furthermore, it is an objective of the invention to provide a method for producing such a planar structure.

[0005] These problems are solved according to the invention by a planar structure according to claim 1 and a method for producing a planar structure according to claim 13. Preferred embodiments of the invention are defined in the dependent claims and in the description. The wording of all claims is hereby incorporated by express reference into the content of this description.

[0006] A thread with a core and a sheath surrounding the core, i.e. a so-called core-sheath thread (thread with a core-sheath structure or thread with a core-sheath construction), is revealed.

[0007] The core of the fiber can be partially, in particular only partially, or completely, i.e., over its entire surface or throughout, surrounded by the sheath. Preferably, the sheath completely surrounds the core of the fiber.

[0008] The thread is particularly characterized by the fact that the thread core contains or consists of a polyetherketone and the sheath contains or consists of a perfluoroalkoxy polymer.

[0009] For the purposes of the present invention, the term "polyetherketone" shall be understood to mean a polymer in whose molecular backbone ketone and ether functionalities occur, in particular alternately.

[0010] For the purposes of the present invention, the term "perfluoroalkoxy polymer" shall be understood to mean a copolymer which is produced by copolymerization of tetrafluoroethylene and a perfluoroalkoxy vinyl ether.

[0011] The core-sheath yarn is distinguished by its particularly advantageous anti-adhesive properties and high temperature resistance, especially up to 260 °C. This makes the core-sheath yarn particularly suitable for the production of sheet structures, especially for the production of sheet structures suitable as conveyor belts, where anti-adhesive properties and sufficient temperature resistance are paramount.

[0012] In one embodiment of the invention, the polyetherketone is a polyaryletherketone.

[0013] For the purposes of the present invention, the term "polyaryletherketone" shall be understood to mean a polymer in whose molecular backbone ketone and ether functionalities occur, in particular alternately, wherein an aryl group, in particular a phenyl group, linked in the (1,4) position is located between a ketone functionality and an ether functionality.

[0014] In a further embodiment of the invention, the polyetherketone (PEK) is selected from the group consisting of polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyetheretheretherketone (PEEEK), polyetheretherketoneketone (PEEKK), polyetherketoneetherketoneketone (PEKEKK) and mixtures of at least two of the aforementioned polyetherketones.

[0015] In a further embodiment of the invention, the polyetherketone is a polyetheretherketone (PEEK). Polyetheretherketone has proven to be particularly temperature-resistant and particularly easy to process, which is why the advantages of the invention are especially evident in this embodiment.

[0016] In a further embodiment of the invention, the perfluoroalkoxy polymer is a polymer or copolymer with a structural element according to the following formula I. where R = C n F 2n+1 and n = 1, 2, 3, 4 or 5.

[0017] In other words, the perfluoroalkoxy polymer in a further embodiment of the invention is a Poly(tetrafluoroethylene-co-perfluoromethyl vinyl ether), i.e., a copolymer produced by copolymerization of tetrafluoroethylene and perfluorovinyl methyl ether; poly(tetrafluoroethylene-co-perfluoroethyl vinyl ether), i.e., a copolymer produced by copolymerization of tetrafluoroethylene and perfluorovinyl ethyl ether; poly(tetrafluoroethylene-co-perfluoropropyl vinyl ether), i.e., a copolymer produced by copolymerization of tetrafluoroethylene and perfluorovinyl propyl ether; poly(tetrafluoroethylene-co-perfluorobutyl vinyl ether), i.e., a copolymer produced by copolymerization of tetrafluoroethylene and perfluorovinyl butyl ether; or poly(tetrafluoroethylene-co-perfluoropentyl vinyl ether), i.e., a copolymer produced by copolymerization of tetrafluoroethylene and perfluorovinylpentyl ether.

[0018] In a further embodiment of the invention, the perfluoroalkoxy polymer is poly(tetrafluoroethylene-co-perfluoropropyl vinyl ether). This perfluoroalkoxy polymer has proven to be particularly temperature-resistant and, at the same time, particularly non-adhesive, which is why the advantages of the invention are (additionally) enhanced in this embodiment.

[0019] In a further embodiment of the invention, the core material comprises 30% to 80% by weight, in particular 35% to 60% by weight, preferably 39% to 57% by weight, based on the total weight of the thread. The core material proportions disclosed in this paragraph have proven to be particularly advantageous both with regard to the processability of the thread, especially with regard to helicalization or spiralization, and with regard to sufficient thread strength. In particular, the core material proportions disclosed in this paragraph have proven to be particularly advantageous for the production of a thermally fixed thread in helical or spiral form.

[0020] In a further embodiment of the invention, the sheath surrounding the yarn core comprises 20 wt.% to 70 wt.%, in particular 40 wt.% to 65 wt.%, preferably 43 wt.% to 61 wt.%, based on the total weight of the yarn. The sheath proportions disclosed in this paragraph have proven to be particularly advantageous with regard to sheath stability, especially in the event of sheath damage. In particular, the sheath proportions disclosed in this paragraph can reduce the risk of the sheath detaching due to insufficient adhesion to the yarn core in the event of sheath damage. Thus, the internal composite stability of the core-sheath yarn according to the invention can be further optimized by the sheath proportions disclosed in this paragraph.

[0021] In a further embodiment of the invention, the thread core has a diameter of 0.3 mm to 1.8 mm, in particular 0.4 mm to 0.8 mm, preferably 0.5 mm to 0.7 mm.

[0022] The thread and / or the thread core can, in principle, have a cornerless, in particular circular, oval or elliptical, cross-section.

[0023] Alternatively, the thread and / or the thread core may have a square or polygonal cross-section, for example a triangular, square, trapezoidal, rhomboidal, pentagonal, hexagonal, star-shaped or cross-shaped cross-section.

[0024] In the case of a non-circular cross-section, the diameter of the thread core is determined according to the present invention based on the greatest possible distance that two points along a circumferential line of the thread core can have from each other.

[0025] Furthermore, the diameter of the thread core can be constant along the entire length of the thread. Alternatively, the diameter of the thread core can vary at least section by section, in particular only section by section or continuously, along the entire length of the thread, especially continuously or discontinuously.

[0026] Preferably, the diameter of the thread core is larger than the thickness of the sheath.

[0027] Alternatively, the thickness of the sheath can be greater than the diameter of the thread core.

[0028] The filament core can furthermore have a length-related mass, i.e. a fineness or titer, of 100 tex to 3500 tex, in particular 170 tex to 680 tex, preferably 270 tex to 520 tex.

[0029] For the purposes of the present invention, the term "tex" shall be understood to mean a unit for indicating the length-related mass, i.e. the fineness or titer, of the thread according to the invention in grams per 1000 meters.

[0030] In a further embodiment of the invention, the sheath surrounding the thread core has a thickness of 0.05 mm to 0.8 mm, in particular 0.06 mm to 0.3 mm, preferably 0.07 mm to 0.15 mm.

[0031] The thickness of the sheath can be constant along the length of the thread. Alternatively, the thickness of the sheath can vary along the length of the thread, at least section by section, in particular only section by section or continuously, and especially discontinuously.

[0032] In a further embodiment of the invention, the thread has an overall diameter (sum of thread core diameter and sheath thickness) of 0.40 mm to 3.4 mm, in particular 0.5 mm to 1.4 mm, preferably 0.6 mm to 1.0 mm. The overall diameter values ​​disclosed in this paragraph have proven to be particularly advantageous for industrial applications.

[0033] In a further embodiment of the invention, the thread has a linear density, i.e., a fineness or titer, of 210 tex to 17,500 tex, in particular 350 tex to 2,900 tex, preferably 530 tex to 1,400 tex. The values ​​disclosed in this paragraph for the linear density of the thread have also proven to be particularly advantageous for industrial applications.

[0034] The thread and / or thread core can furthermore be a monofilament and / or pseudomonofilament and / or multifilament. Preferably, the thread and / or thread core is a monofilament.

[0035] The thread and / or thread core may also be in the form of an endless thread, in particular an endless monofilament and / or an endless pseudomonofilament and / or an endless multifilament.

[0036] For the purposes of this invention, the term "endless thread" shall be understood to mean a thread with a length of at least 160 m to 35,000 m, in particular from 1,000 m to 10,000 m, preferably from 2,000 m to 5,000 m. This definition also applies mutatis mutandis to an endless monofilament, an endless pseudomonofilament, and an endless multifilament as defined in this invention.

[0037] The thread and / or thread core can furthermore, particularly in a cut-to-length state, have a length of 160 m to 35000 m, in particular 1000 m to 10000 m, preferably 2000 m to 5000 m.

[0038] The thread can also be spiral-shaped or helical, i.e. in the form of a spiral or helix, in particular in the form of a circular or oval cylindrical spiral or helix.

[0039] Alternatively, the thread can be spiral-shaped, i.e., in the form of a spiral.

[0040] For the purposes of the present invention, the term "spiral" shall be understood to mean a shape, curve or structure which winds around an axis with a non-constant, i.e. variable, slope and moves away from or closer to the axis depending on the perspective of the observer.

[0041] Furthermore, the yarn, in particular the core and / or the sheath, may contain at least one additive. In particular, only the core or only the sheath may contain at least one additive. The at least one additive may be selected from the group consisting of plasticizers, dyes, pigments, stabilizers, and mixtures of at least two of the aforementioned additives.

[0042] Furthermore, the thread is preferably temperature resistant in a temperature range of -30 °C to 280 °C, in particular 0 °C to 270 °C, preferably 20 °C to 260 °C.

[0043] According to a first aspect, the invention relates to a planar structure, preferably a textile planar structure, comprising the core-sheath thread.

[0044] The sheet structure has several adjacent and neighboring interlocking helices, i.e., helical coils, and / or spirals, as well as several connecting threads which are inserted into overlapping helix and / or spiral sections of the adjacent helices and / or spirals to connect the helices and / or spirals to one another, wherein the helices and / or spirals each have at least one thread with a core and a sheath surrounding the core, wherein the core comprises a polyetherketone and the sheath surrounding the core comprises a perfluoroalkoxy polymer.

[0045] The connecting threads can each have a cornerless, in particular circular, oval or elliptical, cross-section.

[0046] Alternatively, the connecting threads can each have a square or polygonal cross-section, for example triangular, square, trapezoidal, rhomboidal, pentagonal, hexagonal, star-shaped or cross-shaped cross-section.

[0047] Furthermore, the planar structure can contain both threads with a cornerless cross-section and threads with a square or polygonal cross-section. Reference is made to the two preceding paragraphs in this respect.

[0048] Furthermore, the connecting threads can each have a diameter of 0.4 mm to 2.0 mm, in particular 0.5 mm to 1.2 mm, preferably 0.6 mm to 0.9 mm.

[0049] Furthermore, the diameter of the connecting threads can be constant along their entire length. Alternatively, the diameter of the connecting threads can vary at least section by section, in particular only section by section or continuously, especially continuously or discontinuously.

[0050] Furthermore, the connecting threads can each be designed as monofilament, pseudomonofilament, or multifilament. In particular, the sheet structure can comprise monofilament connecting threads and / or pseudomonofilament connecting threads and / or multifilament connecting threads. Preferably, the connecting threads are each monofilament.

[0051] The connecting threads can each have a length-related mass of 170 tex to 4200 tex, in particular 260 tex to 1500 tex, preferably 370 tex to 840 tex.

[0052] Furthermore, the connecting threads may contain polyphenylene sulfide (PPS) and / or polyetheretherketone (PEEK) or consist of polyphenylene sulfide (PPS) and / or polyetheretherketone (PEEK).

[0053] Alternatively, the connecting threads can each be a thread according to the first aspect of the invention.

[0054] Furthermore, the surface structure can have a combination of connecting threads, as described in the two preceding paragraphs.

[0055] Preferably, the planar structure exhibits an alternating sequence of right- and left-handed helices and / or spirals.

[0056] A helix or spiral is clockwise within the meaning of the present invention if the shape, curve or structure of the helix or spiral winds in a clockwise direction (as seen in the direction in which it moves away from the viewer).

[0057] A helix or spiral is left-handed within the meaning of the present invention if the shape, curve or structure of the helix or spiral winds counterclockwise (in the direction in which it moves away from the viewer).

[0058] Furthermore, it is preferred if the helices and / or spirals are dimensioned identically to each other.

[0059] Furthermore, the free cross-sections of the helices and / or spirals can contain filler material. This allows for a reduction in the air permeability of the surface structure.

[0060] The filler materials may, for example, consist of one or more threads, in particular one or more monofilaments, comprising or made of polyetheretherketone (PEEK), polyphenylene sulfide (PPS), perfluoroalkoxy polymer (PFA polymer) or another high-temperature resistant polymer.

[0061] Furthermore, it is preferred if the surface structure is thermofixed.

[0062] The sheet material is particularly preferred as a spiral sieve or for the production of a spiral sieve, especially in the paper industry.

[0063] Furthermore, the surface structure can be used in particular as a filter, especially a drying filter, for example in presses or in the food industry.

[0064] The sheet-like structure is preferably used as a transport or conveyor belt for transporting or conveying products, such as nonwoven products. These products may be, in particular, those that become sticky at higher temperatures, for example, temperatures above 200 °C.

[0065] Regarding further features and advantages of the surface structure, full reference is made to the explanations given in the context of the first aspect of the invention and to the description that follows.

[0066] A method for producing a thread is also disclosed.

[0067] In this process, a thread, in particular a monofilament, comprising or consisting of a polyetherketone, is coated with a perfluoroalkoxy polymer.

[0068] The filament, in particular the monofilament, can be heated before being coated with the perfluoroalkoxy polymer. For example, the filament, in particular the monofilament, can be heated to a temperature of 50 °C to 200 °C, in particular 80 °C to 150 °C, preferably 90 °C to 110 °C. Furthermore, the filament, in particular the monofilament, can be heated for a period of 1 hour to 5 days, in particular 12 hours to 2 days, preferably 20 hours to 28 hours. By heating the filament, in particular the monofilament, volatile components, such as a coating, can be eliminated or at least their proportion in the filament, in particular the monofilament, which could otherwise impair the coating of the filament, in particular the monofilament.

[0069] Alternatively, in the process a filament core comprising or consisting of a polyetherketone, and a sheath comprising or consisting of a perfluoroalkoxy polymer, are co-extruded from a shaping outlet opening of an extrusion device to form a filament with a filament core and a sheath surrounding the filament core.

[0070] The extrusion device can have one extruder for the yarn core and one for the sheath. Each extruder can be operated with its own spinning pump. Furthermore, the extrusion device can have a first melting channel for conveying molten yarn core material and a second melting channel for conveying molten yarn sheath material. Advantageously, the second melting channel can surround the first melting channel, particularly concentrically. Advantageously, the first and second melting channels open into the outlet of the extrusion device.

[0071] Regarding further features and advantages of the method, reference is made in full to the explanations given in the previous section on the invention and to the description that follows.

[0072] According to a second aspect, the invention relates to a method for producing a sheet structure, preferably a textile sheet structure, according to the first aspect of the invention. The method comprises the following steps: a) Converting several threads with a thread core and a sheath surrounding the thread core, wherein the thread core comprises a polyetherketone and the sheath surrounding the thread core comprises a perfluoroalkoxy polymer, into several helices and / or spirals, b) overlapping joining of the helices and / or spirals and c) connecting the overlapping joined helices and / or spirals by inserting connecting threads into overlapping areas of the overlapping joined helices and / or spirals.

[0073] Before carrying out step a), the threads can be heated, in particular with a forced-air heater. The temperature of the forced-air heater can be set to a temperature of 20 °C to 400 °C, in particular 100 °C to 350 °C, preferably 200 °C to 300 °C.

[0074] Preferably, step a) is carried out such that the helices and / or spirals each consist of only one thread with a core and a sheath surrounding the core, wherein the core comprises a polyetherketone and the sheath surrounding the core comprises a perfluoroalkoxy polymer, or each consist of only one thread with a core and a sheath surrounding the core, wherein the core comprises a polyetherketone and the sheath surrounding the core comprises a perfluoroalkoxy polymer.

[0075] Furthermore, it is preferred that, to carry out step a), the threads are each wound around a winding mandrel, in particular a cylindrical, preferably circular-cylindrical, or conically shaped winding mandrel. It is particularly preferred that a portion of the threads, i.e., one or more threads, are wound clockwise around the winding mandrel, while a remaining portion of the threads, i.e., a remaining number of threads, are wound counterclockwise around the winding mandrel.

[0076] In particular, the threads wound onto the winding mandrel can be heated, for example by means of a heater. The temperature of the heater can be set to a temperature of 160 °C to 320 °C, in particular 200 °C to 300 °C, preferably 220 °C to 260 °C.

[0077] Furthermore, it is preferred if, when performing step b), alternating right- and left-handed helices and / or spirals are joined together in an overlapping manner.

[0078] Preferably, when performing step c), the connecting threads are inserted into overlapping helix and / or spiral areas of each pair of adjacent helices and / or spirals in the longitudinal direction of the helices and / or spirals.

[0079] Preferably, when performing step c), only a single connecting thread is inserted into the overlapping areas of the overlapping helices and / or spirals joined together.

[0080] Furthermore, it is preferred if the process includes a further step d) of thermosetting the joined helices and / or spirals. This allows shrinkage processes and stresses to be induced in the helices and / or spirals, thereby reducing the thickness of the sheet structure. Step d) can be carried out in particular by calendering and / or at a temperature of 200 °C to 280 °C, especially 230 °C to 260 °C.

[0081] Furthermore, the process may include a further step cd) between steps c) and d) introducing filler material into free cross-sections or free cavities, in particular free longitudinal cavities, of the connected helices and / or spirals.

[0082] Alternatively, the process after step d) can include a further step e) introducing filler material into free cross-sections or free cavities, in particular free longitudinal cavities, of the connected helices and / or spirals and subsequently heat-setting the connected helices and / or spirals filled with filler material. The subsequent heat-setting can be carried out in particular by calendering and / or at a temperature of 200 °C to 280 °C, in particular 230 °C to 260 °C.

[0083] Furthermore, the process according to step c), d) or e) may include a further step f) finishing the sheet structure. For example, the sheet structure may be cut to customer-specific dimensions, in particular to a specific length and / or width, and / or its edges may be straightened and / or fixed, in particular by welding.

[0084] Regarding further features and advantages of the method, reference is made in full to the explanations given in the previous section on the invention and to the description that follows.

[0085] Further features and advantages of the invention will become apparent from the following description of preferred embodiments in the form of figures, figure descriptions, and exemplary embodiments, as well as the dependent claims. Individual features may be implemented individually or in combination with one another. The preferred embodiments serve only to further explain and improve understanding of the invention, without limiting it thereto. FIGURE DESCRIPTION

[0086] The figures schematically depict the following Fig. 1: a cross-sectional view of a core-sheath thread according to the present invention, Fig. 2a: a cross-sectional view of an embodiment of a sheet structure according to the present invention, Fig. 2b: a top view of the in Fig. 2aFigure 3a: a cross-sectional view of a further embodiment of a surface structure according to the present invention, and Figure 3b: a top view of the surface structure shown in ...b: a cross-sectional view of a further embodiment of a surface structure according to the present invention. Fig. 3a depicted surface structure. DETAILED FIGURE DESCRIPTION

[0087] The Fig. 1 Figure 1 schematically shows a cross-section of a thread 10 according to the invention, comprising a thread core 12 and a sheath 14 surrounding the thread core 12. The thread core 12 comprises or consists of a polyetherketone. Preferably, the polyetherketone is polyetheretherketone. The sheath 14 comprises or consists of a perfluoroalkoxy polymer. The perfluoroalkoxy polymer is preferably a copolymer produced by copolymerization of tetrafluoroethylene and perfluorovinyl propyl ether.

[0088] Thread 10 can, as in Fig. 1The thread shown has a circular cross-section. It is understood that the thread 10 can alternatively have a non-circular cross-section.

[0089] The Figs. 2a to 3b Figure 1 schematically shows a planar structure 1 according to the present invention.

[0090] The surface structure 1 has a plurality of helices 2 and / or spirals 2. The helices 2 and / or spirals 2 are preferably identically dimensioned to each other.

[0091] Each helix 2 and / or spiral 2 is wound, particularly endlessly, from a core-sheath thread, i.e., from a thread with a core and a sheath surrounding the core. The core comprises or consists of a polyetherketone. The sheath comprises or consists of a perfluoroalkoxy polymer. The polyetherketone is preferably polyetheretherketone. The perfluoroalkoxy polymer is preferably a copolymer produced by copolymerization of tetrafluoroethylene and perfluorovinylpropyl ether.

[0092] As can be seen from the cross-sectional views according to the Fig. 2a and 3aAs can be seen, each helix 2 and / or spiral 2 has an oval cross-section. To produce the sheet structure 1, the individual helices 2 and / or spirals 2 are placed side by side, alternating with each other, in the opposite winding direction, and the side edge regions of their turns are inserted between corresponding side edge regions of the turns of the adjacent helix 2 and / or spiral 2. As can be seen from the Fig. 2 federal 3b As can be seen, this results in two helix segments and / or spiral segments overlapping each other in an alternating, turn-by-turn fashion for the adjacent helices 2 and / or spirals 2. Based on the Fig. 2a and 3aIt can be seen that, through this superposition of the helical sections and / or spiral sections of the adjacent helices 2 and / or spirals 2, channel sections are formed in the longitudinal direction of the helices 2 and / or spirals 2, through which threads 3 are pushed or pulled in the longitudinal direction in order to connect the adjacent helices 2 and / or spirals 2 with each other.

[0093] As shown by the Fig. 2a and 3aFurthermore, it can be seen that after the helices 2 and / or spirals 2 are connected, continuous free cross-sections 4 are created in the longitudinal direction of each helix 2 and / or spiral 2 of the surface structure 1, i.e., in the longitudinal direction of the connecting threads 3. The free cross-sections 4 are bounded laterally, i.e., viewed in the plane of the surface structure 1, by corresponding outer edge regions of the helix segments and / or spiral segments of the helices 2 and / or spirals 2 adjacent to the left and right. Above and below, the free cross-sections 4 are bounded by upper and lower winding sections of the respective helix 2 and / or spiral 2, which simultaneously define an upper and a lower contact surface of the surface structure 1.

[0094] As shown by the Fig. 3aAs can be seen, the width B of each free cross-section 4 corresponds to the clear distance between opposite side edge regions of the helical sections and / or spiral sections of the adjacent helices 2 and / or spirals 2. The clear height H of the free cross-section 4 is defined by the size difference between the upper and lower winding sections of the respective helix 2 and / or spiral 2. In the illustrated embodiment, this greatest distance is located in the center of the respective free cross-section 4. Based on the Fig. 3a An outer width A and a total height G of each helix 2 and / or spiral 2 are also defined.

[0095] Filling bodies F can be inserted longitudinally into the free cross-sections 4, which are largely adapted to the cross-sectional dimensions of the respective free cross-section 4, as shown by the Figs. 3a and 3bThis is evident from the top view of the surface structure 1. After the insertion of the filler material F, only small air openings L remain, which can be seen from the Fig. 3b are recognizable and lie between the lateral edge edges of the filler bodies F and the plug wires 3 as well as the correspondingly superimposed helix sections and / or spiral sections of the adjacent helices 2 and / or spirals 2.

[0096] The above statements apply to both thermally fixed and thermally unfixed sheet structures. This is because, during thermal fixing, the sheet structures undergo thermal stress in addition to stretching, causing them to shrink to a reduced thickness.

[0097] The in the Figs. 2a to 3bThe depicted surface structure can be used, for example, as a transport or conveyor belt for transporting or conveying products, especially nonwoven products, or for manufacturing such a belt. SAMPLE PART 1. core of the thread

[0098] Two different monofilaments made of polyetheretherketone (PEEK) of type P115S, namely core (1) and core (2), with the following properties were used as filament cores: fiber core (1) fiber core (2) material PEEK PEEK diameter 0.55 mm 0.60 mm Thread fineness 310 tex 370 tex Aviage salary No avivage High (spiralization) Maximum tensile strength 121 N 143 N Strength: 39.1 cN / tex 38.6 cN / tex Stretching 17,9 19,2% Shrinkage (180°C) KA 10,3% Shrinkage (200°C) 14,0 14,8% Length of 1 kg material. 3226 2703 2. Coat

[0099] Poly(tetrafluoroethylene-co-perfluoropropylvinyl ether) (CAS No.: 26655-00-5) was used as the perfluoroalkoxy polymer to coat the filament cores mentioned under 1.

[0100] The thread core (1) contained no aviage.

[0101] The fiber core (2) contained a finish and was subjected to an oven treatment prior to the sheathing step in order to remove a volatile portion of the finish. For this purpose, the fiber core (2) was tempered for 24 hours at 90 °C.

[0102] The sheathing of the thread cores (1) resulted in core-sheath threads (1). The sheathing of the thread cores (2) resulted in core-sheath threads (2). The core-sheath threads (1) and (2) exhibited the following properties: K / M threads (1) K / M threads (2) Material designation: 0,55 / 0,72 0,60 / 0,85 PEEK diameter [mm] 0,55 0,6 Total diameter [mm] 0,72 0,85 Total fineness 729 904 Length of 1 kg monofilament [m] 1371,7 1106,2 Total cross-sectional area 0,4072 0,5675 Core area (PEEK) 0,2376 0,2827 Ring surface (PFA) 0,1696 0,2847 Volume PEEK in 100 m mono [cm 3< ] 23,76 28,27 Volume of PFA in 100 m mono [cm 3< ] 16,96 28,47 Mass of PEEK in 100 m Mono [g] 31,0 37,0 Mass of PFA in 100 m Mono [g] (calculated from difference in weight) 41,9 53,4 Percentage by weight of PEEK 42,5% 40,9% Percentage by weight PFA 57,5% 59,1%

[0103] Legend: K / M threads (1) = core-sheath threads (1); K / M threads (2) = core-sheath threads (2) 3. Helicalization:

[0104] The core-sheath threads (1) and (2) were applied to a winding mandrel after preheating and heated on the winding mandrel. 4. Joining the helices:

[0105] Equally dimensioned helices (1) were joined alternately left- and right-handed, overlapping each other, and provided with connecting threads to create a surface structure (1).

[0106] Equally dimensioned helices (2) were also joined alternately left- and right-handed, overlapping each other, and provided with connecting threads to create a surface structure (2).

[0107] The fabricated surface structures (1) and (2) exhibited the following properties: Planar structures (1) Planar structures (2) Core-sheath thread: PEEK / PFA - 0.55 / 0.72 PEEK / PFA - 0.60 / 0.85 winding mandrel dimensions: 6,85 x 3,85 6,80 x 4,50 Thread: 0.70 mm PEEK 0.70 mm PEEK Fineness of the sewing thread: 500 tex 500 tex Number of helices / m 214 232 basis weights Helical threads: 1475 1980 Threads: 107 116 in total: 1582 2096 5. Thermosetting on the calender:

[0108] The sheet structures (1) and (2) were each installed between two feed belts and thermofixed under the following conditions using a calender: Temperature setting: 250°C (maximum) Speed: 0.3 m / min

Claims

1. A sheet material having several helices and / or coils arranged next to one another and adjacently engaging in one another, and several insert threads which are, for connecting the helices and / or coils to one another, inserted into helical and / or coiled sections, overlapping one another, of the adjacent helices and / or coils, characterized in that the helices and / or coils each have at least one thread with a thread core and with a jacket surrounding the thread core, wherein the thread core has a polyetherketone and the jacket surrounding the thread core has a perfluoroalkoxy polymer.

2. The sheet material according to claim 1, characterized in that the polyetherketone is a polyaryletherketone.

3. The sheet material according to claim 1 or 2, characterized in that the polyetherketone is selected from the group consisting of polyetheretherketone, polyetherketoneketone, polyetheretheretherketone, polyetheretherketoneketone, polyetherketoneetherketoneketone and mixtures of at least two of the stated polyetherketones.

4. The sheet material according to any of the preceding claims, characterized in that the polyetherketone is polyetheretherketone.

5. The sheet material according to any of the preceding claims, characterized in that the perfluoroalkoxy polymer is a polymer with a structural element according to formula I, wherein R = CnF2n+1 and n = 1, 2, 3, 4 or 5.

6. The sheet material according to any of the preceding claims, characterized in that the perfluoroalkoxy polymer is poly(tetrafluoroethylene-co-perfluoropropylvinylether).

7. The sheet material according to any of the preceding claims, characterized in that the thread core has a proportion of 30 to 80 % by wt., in particular 35 to 60 % by wt., preferably 39 to 57 % by wt., relative to the total weight of the thread.

8. The sheet material according to any of the preceding claims, characterized in that the jacket surrounding the thread core has a proportion of 20 to 70 % by wt., in particular 40 to 65 % by wt., preferably 43 to 61 % by wt., relative to the total weight of the thread.

9. The sheet material according to any of the preceding claims, characterized in that the thread core has a diameter of 0.3 to 1.8 mm, in particular 0.4 to 0.8 mm, preferably 0.5 to 0.7 mm.

10. The sheet material according to any of the preceding claims, characterized in that the jacket surrounding the thread core has a thickness of 0.05 to 0.8 mm, in particular 0.06 to 0.3 mm, preferably 0.07 to 0.15 mm.

11. The sheet material according to any of the preceding claims, characterized in that the thread has a total diameter of 0.4 to 3.4 mm, in particular 0.5 to 1.4 mm, preferably 0.6 to 1.0 mm.

12. The sheet material according to any of the preceding claims, characterized in that the thread has a mass by length of 210 to 17500 tex, in particular 350 to 2900 tex, preferably 530 to 1400 tex.

13. A method for manufacturing a sheet material according to any of the preceding claims, having the steps: a) transfer of several threads with a thread core and with a jacket surrounding the thread core, into several helices and / or coils, wherein the thread core has a polyetherketone and the jacket surrounding the thread core has a perfluoroalkoxy polymer, b) overlapping joining of the helices and / or coils to one another and c) connection of the helices and / or coils overlappingly joined to one another by insertion of insert threads into overlapping areas of the helices and / or coils overlappingly joined to one another.

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