Conveyor belt core comprising one or more impregnated nonwoven fabric layers

Abstract

The invention provides a belt core. The belt core comprises one, two or more impregnation layers; i) each impregnated layer comprises or consists essentially of a non-woven fabric and an impregnated material, the impregnated material comprising or consists essentially of a first thermoplastic, a first thermoplastic elastomer, a first elastomer or a first thermoset, and optionally additives; ii) if there are two or more impregnated layers adjacent to each other, ii) if the belt core comprises one or more impregnated layers, reinforcing filaments extending at least partially in a given direction and in the form of a filament layer are embedded in the nonwoven fabric of exactly one of the impregnated layers; or if the belt core comprises two or more impregnated layers, reinforcing filaments extending at least partially in a given direction and in the form of exactly one filament layer are sandwiched between two adjacent impregnated layers, and iii) the belt core is free of woven fabric. The tape core may be cut into longitudinal tapes or into discs or corner tapes.

Description

[0001] This application is a divisional application of a patent application filed in China on April 12, 2021, with the national application number 201980067361.9, and the invention name is “Conveyor belt core comprising one or more impregnated nonwoven fabric layers”. Technical Field

[0002] The invention relates to a belt core, in particular for a conveyor belt, a machine belt, a power transmission belt or a spindle belt, the belt core comprising an impregnation layer and reinforcing filaments. Background Art

[0003] Belts based on woven fabrics are widely used as conveyor belts, machine belts or power transmission belts, for example. Woven fabrics act as traction layers. The fabric is also flexible. Belt flexibility is required to allow the belt to bend on small radius wheels. However, since woven fabrics always have a certain elasticity in the longitudinal (belt travel) direction, the belts produced in this way may not have enough toughness in the longitudinal direction. In order to counteract this, it is also recommended to include high-toughness reinforcing filaments extending in the longitudinal direction of the belt into the belt as an alternative to the woven fabric or a supplement to the woven fabric.

[0004] In many cases, the woven fabric is covered with a polymer material. The coating seals the fabric from the environment. This prevents the conveyed items from being contaminated by the fabric fibers, and if the belt begins to wear and is not coated, the belt will require edge sealing of the woven fabric as an additional manufacturing step to prevent such fiber contamination or further degradation of the textile material. The coating can also act as a support for subsequent cover layers (one or more) that the belt may have in order to adapt to its intended application, and due to its well-defined geometric surface, also gives the cover layer (one or more) the same well-defined geometric surface (one or more).

[0005] In order to best adhere the coating(s) to the woven fabric, at least partially hairy natural fibers may be included (these fibers aid in adhesion to the coated material through their hairy mechanical attachment points); or, in the case of synthetic fibers that are substantially free of such hairy attachment points, adhesion promoters may be used in conjunction. However, the effectiveness of adhesion promoters is reduced by the subsequent manufacturing and preparation processing of synthetic fabric-based belts and harsh product applications (particularly extreme heating / cooling and repeated high stress applications), resulting in poor product integrity and separation along the interface, which leads to various undesirable (delamination / separation) product performance (durability, life) issues.

[0006] The presence of both the coating and the reinforcing longitudinal fibers in the belt may give rise to the problem that during use of the belt and during bending on the wheel, these longitudinal fibers begin to cut longitudinally through the coated material, which may lead to premature belt failure. Therefore, it has been suggested to embed and wrap such reinforcing fibers in a woven fabric. Here, the transverse (weft) fibers of the fabric at least to some extent prevent the longitudinal cutting. GB 1 390 603 discloses a conveyor belt in which the woven fabric embeds longitudinal reinforcing filaments.

[0007] US Patent 2008 / 078657A1 discloses a conveyor belt having at least two nonwoven layers, which may be needle-punched felts and are preferably needle-punched together. One of the two nonwoven layers is in contact with an elastomer 12, and preferably both nonwoven layers are impregnated with the elastomer 12. This conveyor belt has no reinforcing filaments.

[0008] U.S. Patent 2008 / 0164127A1 discloses a conveyor belt having a nonwoven layer, a woven layer and an optional second nonwoven layer, so that the nonwoven layer is on the opposite side of the woven layer, and these nonwoven layers are needled together. An elastomer is used to engage the woven layer and the nonwoven layer. The elastomer can be optionally impregnated into the belt core to reach a desired and adjustable degree. In one embodiment, one side of the resulting belt core is soaked with elastomer 12, and the other side remains exposed. Example 1 discloses a conveyor belt having two layers of nonwoven materials and a core layer woven scrim with a synthetic rubber compound cover. The nonwoven layer itself does not have reinforcing filaments.

[0009] JP 2007 / 137993 A discloses a heat-resistant conveyor belt comprising a nonwoven textile layer 2 laminated to a base fabric 3 consisting of several layers of warp yarns 11 and weft yarns 12. The nonwoven textile layer 2 and the base fabric 3 are needled together. Optionally, there may be another nonwoven textile layer 5 on the other side of the base fabric 3. The base fabric 3 is impregnated with a resin material. Apart from the warp yarns 11, which are said to have "high strength", there are no other reinforcing filaments.

[0010] GB 1 354 689 discloses an elastomeric article which may be a conveyor belt having a reinforcement comprising an assembly of longitudinally extending continuous parallel filaments. This elastomeric article preferably also comprises a woven fabric reinforcement layer. In Example 3, a reinforcement belt is disclosed in which a carded web of PET staple fibers is saturated with an aqueous latex dispersion and "placed on top of and in contact with the assembly of parallel filaments".

[0011] WO 2017 / 102768 A1 describes a sheet consisting of a mixture consisting essentially of randomly oriented fibers and a thermoplastic or a thermoplastic elastomer, and its use as a support or as a top layer in a stamping belt in a stamping application. The sheet itself can be made of N geometrically well-defined polymer sheets and K types of fibers, wherein each k-th type of fiber can be in the form of a corresponding preassembled sheet, such as a nonwoven fabric.

[0012] The present invention seeks to provide an improved tape core which takes into account all of the aforementioned facts and problems and which is suitable for preparing different tape types therefrom. Summary of the invention

[0013] Therefore, the present invention provides:

[0014] A belt core comprising one, two or more impregnation layers; characterized in that

[0015] Each impregnated layer comprises or consists essentially of a nonwoven fabric and an impregnated material comprising or consisting essentially of a first thermoplastic, a first thermoplastic elastomer, a first elastomer or a first thermosetting plastic and optional additives; whereby, if there are two or more such impregnated layers, they are adjacent to each other and

[0016] If the tape core comprises one or more such impregnation layers, the reinforcing filaments extending at least partially in one given direction and in the form of one filament layer are embedded in the nonwoven fabric of exactly one of said impregnation layers; or

[0017] If the tape core comprises two or more such impregnation layers, reinforcing filaments extending at least partially in one given direction and in the form of exactly one filament layer are sandwiched between two adjacent such impregnation layers.

[0018] A corner tape obtainable by cutting circular segments from a tape core according to claim 7, wherein the filament layers (51, 52, 53) are in the form of a grid of reinforcing filaments with a square grid.

[0019] A method for manufacturing the above-mentioned belt core, the belt core comprising one or more impregnation layers (21, 22, 23, 24, 25), the method comprising the following steps:

[0020] i-1) providing a first nonwoven sublayer (31), a second nonwoven sublayer (32) and reinforcing filaments in the form of a filament layer (51), wherein the reinforcing filaments extend at least partially in one given direction;

[0021] i-2) arranging the filament layer (51) on top of the second non-woven sub-layer (32), and arranging the first non-woven sub-layer (31) on top of the filament layer (51);

[0022] i-3) bonding the first nonwoven sublayer (31) and the second nonwoven sublayer (32) together to form a first nonwoven fabric (3) embedded with reinforcing filaments (51), wherein the reinforcing filaments (51) extend at least partially in the one given filament direction;

[0023] i-4) impregnating the first nonwoven fabric (3) with a first impregnation material (4), the first impregnation material comprising a first thermoplastic, a first thermoplastic elastomer, a first elastomer or a first thermosetting plastic and optional additives, or the first impregnation material essentially consisting of a first thermoplastic, a first thermoplastic elastomer, a first elastomer or a first thermosetting plastic and optional additives, to form a first impregnation layer (21) embedded with a filament layer (51);

[0024] i-5) optionally and independently of steps i-1) to i-4), or

[0025] i-5-a) providing one or more additional nonwoven fabrics (303, 304, 305) and one or more additional sheets (403, 404, 405) of additional impregnating material, the additional impregnating material comprising or consisting essentially of additional thermoplastics, additional thermoplastics, additional elastomers or additional thermosetting plastics and optional additives;

[0026] i-5-b) arranging the one or more additional nonwoven fabrics (303, 304, 305) and the one or more additional sheets (403, 404, 405) adjacent to the first impregnated layer (21) and adjacent to each other so that there is at least one additional sheet immediately adjacent to any nonwoven fabric and at least one additional nonwoven fabric immediately adjacent to any additional sheet;

[0027] i-5-c) simultaneously using heat and pressure to impregnate any additional nonwoven fabric with the impregnation material from at least one additional sheet adjacent to the nonwoven fabric to form a corresponding impregnated layer (21, 22, 23, 24, 25), and to combine any of the impregnated layers (21, 22, 23, 24, 25) and the first impregnated layer (21); or

[0028] i-5-d) providing one or more additional impregnation layers (22, 23, 24, 25), each additional impregnation layer comprising or consisting of an additional nonwoven fabric, the additional nonwoven fabric being impregnated with an additional impregnation material, the additional impregnation material comprising an additional thermoplastic, an additional thermoplastic, an additional elastomer or an additional thermosetting plastic and optional additives, or the additional impregnation material essentially consisting of an additional thermoplastic, an additional thermoplastic, an additional elastomer or an additional thermosetting plastic and optional additives, and each additional impregnation layer being free of reinforcing filaments;

[0029] i-5-e) arranging the one or more additional impregnation layers (22, 23, 24, 25) adjacent to the first impregnation layer (21) and adjacent to each other; and combining any of the additional impregnation layers (21, 22, 23, 24, 25) and the first impregnation layer (21) together using heat and pressure.

[0030] A method for manufacturing the above-mentioned belt core, the belt core comprising two or more impregnation layers (21, 22, 23, 24, 25), the method comprising the following steps:

[0031] ii-1) providing a first nonwoven fabric (301), a second nonwoven fabric (302), a first sheet (401) of a first impregnating material, a second sheet (402) of a second impregnating material, and reinforcing filaments, wherein the first impregnating material comprises a first thermoplastic, a first thermoplastic elastomer, a first elastomer or a first thermosetting plastic and optional additives, or the first impregnating material consists essentially of the first thermoplastic, the first thermoplastic elastomer, the first elastomer or the first thermosetting plastic and optional additives, the second impregnating material comprises a second thermoplastic, a second thermoplastic elastomer, a second elastomer or a second thermosetting plastic and optional additives, or the second impregnating material consists essentially of the second thermoplastic, the second thermoplastic elastomer, the second elastomer or the second thermosetting plastic and optional additives, and the reinforcing filaments are in the form of a filament layer (52), wherein the reinforcing filaments extend at least partially in a given direction;

[0032] ii-2) arranging the filament layer (52), the first nonwoven fabric (301), the second nonwoven fabric (302), the first sheet material (401) and the second sheet material (402) adjacent to each other so that the first nonwoven fabric (301) and the first sheet material (401) are present on one side of the filament layer (52), and the second nonwoven fabric (302) and the second sheet material (402) are present on the other side of the filament layer (52), so that the filament layer (52) is sandwiched between the first nonwoven fabric (301) and the first sheet material (401) on the one hand, and between the second nonwoven fabric (302) and the second sheet material (402) on the other hand, to form a layered composite material (6);

[0033] ii-3) optionally and independently of steps ii-1) to ii-2), or

[0034] ii-3-a) providing one or more further nonwoven fabrics (303, 304, 305) and one or more further sheets (403, 404, 405) of further impregnation material, the further impregnation material comprising or consisting essentially of further thermoplastics, further thermoplastics, further elastomers or further thermosetting plastics and optional additives;

[0035] ii-3-b) arranging the one or more additional nonwoven fabrics (303, 304, 305) and the one or more additional sheets (403, 404, 405) adjacent to the layered composite material (6) and adjacent to each other such that there is at least one additional sheet immediately adjacent to any nonwoven fabric and there is at least one additional nonwoven fabric immediately adjacent to any additional sheet;

[0036] ii-3-c) impregnating any nonwoven fabric (301 or 302 or 303 or 304 or 305) with an impregnating material from at least one additional sheet (respectively 401 or 402 or 403 or 404 or 405) adjacent to the nonwoven fabric using heat and pressure simultaneously to form a corresponding impregnated layer (respectively 21 or 22 or 23 or 24 or 25); and combining all of the impregnated layers (21, 22, 23, 24, 25) and the layered composite material (6); or

[0037] ii-3-d) providing one or more further impregnated layers (22, 23, 24, 25), each further impregnated layer comprising or consisting of a further nonwoven fabric, said further nonwoven fabric being impregnated with a further impregnating material, said further impregnating material comprising or consisting essentially of a further thermoplastic, a further thermoplastic, a further elastomer or a further thermosetting plastic and optional additives, and each further impregnated layer being free of reinforcing filaments;

[0038] ii-3-e) arranging the one or more further impregnation layers (22, 23, 24, 25) adjacent to the layered composite material (6) and adjacent to each other;

[0039] ii-3-f) bonding together any said further impregnated layers (21, 22, 23, 24, 25) and said layered composite material (6) using heat and pressure,

[0040] Therein the direction of the filaments will form the direction of travel of the tape.

[0041] A method for manufacturing the above-mentioned belt core, the belt core comprising two or more impregnation layers (21, 22, 23, 24, 25), the method comprising the following steps:

[0042] iii-1) providing reinforcing filaments in the form of a filament layer (53), and a first impregnation layer (21), wherein the reinforcing filaments extend at least partially in a given direction, the first impregnation layer comprises a first non-woven fabric or consists of the first non-woven fabric, the first non-woven fabric is impregnated with a first impregnation material, the first impregnation material comprises a first thermoplastic, a first thermoplastic elastomer, a first elastomer or a first thermosetting plastic and optional additives, or the first impregnation material essentially consists of a first thermoplastic, a first thermoplastic elastomer, a first elastomer or a first thermosetting plastic and optional additives, but the first non-woven fabric does not have reinforcing filaments;

[0043] iii-2) or

[0044] iii-2-a) providing one or more additional nonwoven fabrics (306, 307, 308) and one or more additional sheets (406, 407, 408) of additional impregnation material, the additional impregnation material comprising or consisting of an additional thermoplastic material, an additional thermoplastic elastomer, an additional elastomer or an additional thermosetting material and optional additives, the number of additional nonwoven fabrics (306, 307, 308) being equal to the number of additional sheets (406, 407, 408), and the number of additional nonwoven fabrics (306, 307, 308) being designated K;

[0045] iii-2-b) arranging a further nonwoven fabric (306), a further sheet material (406) and the optional filament layer (53) on one side of the first impregnation layer (21) and adjacent to the first impregnation layer (21) so that, when the optional filament layer (53) is provided, the filament layer (53) is sandwiched between the first impregnation layer (21) on the one hand and is sandwiched by the further nonwoven fabric (306) and the further sheet material (406) on the other hand;

[0046] iii-2-c) impregnating the further nonwoven fabric (306) with the impregnation material from the further sheet (406) using heat and pressure simultaneously to form a further impregnated layer (22), and bonding the first impregnated layer (21), the optional sandwiched filament layer (53) and the further impregnated layer (22) together to form a bonded layered composite material (7);

[0047] iii-2-d) using yet another pair (307 / 407, 308, 408) of yet another nonwoven fabric and yet another sheet, wherein the yet another sheet is a sheet of yet another thermoplastic, yet another thermoplastic elastomer, yet another elastomer or yet another thermosetting plastic and optional additives, repeating steps iii-2-b) and iii-2-c) K-1 times on the combined layered composite material (7), but in steps iii-2-b) and iii-2-c) and in the repetition of steps iii-2-b) and iii-2-c), the filament layer (53) is used exactly once in total; or

[0048] iii-2-e) providing one or more further impregnated layers (22, 23, 24, 25), each of the one or more further impregnated layers comprising or consisting of a further nonwoven fabric, the further nonwoven fabric being impregnated with a further impregnating material comprising or consisting essentially of a further thermoplastic, a further thermoplastic elastomer, a further elastomer or a further thermosetting plastic and optional additives, the number of the further impregnated layers (22, 23, 24, 25) being designated K;

[0049] iii-2-f) arranging a further impregnation layer (22) on one side of the first impregnation layer (21) and adjacent to the first impregnation layer (21) so that, in case the optional filament layer (53) is provided, the filament layer (53) is sandwiched between the first impregnation layers (21) on the one hand and by the second impregnation layers (22) on the other hand;

[0050] iii-2-g) bonding together the first impregnated layer (21), the optional sandwiched filament layer (53) and the further impregnated layer (21) using heat and pressure to form a bonded layered composite material (7);

[0051] iii-2-h) Repeating steps iii-2-f) and step iii-2-g) K-1 times on the combined layered composite material (7), using one of the further impregnation layers (23, 24, 25) in each repetition, but in steps iii-2-f) and iii-2-g) and in the repeated steps of steps iii-2-f) and iii-2-g), the filament layer (53) is used exactly once in total. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 A transparent top view of a tape showing different embodiments of an embedding of a filament layer comprising reinforcing filaments.

[0053] Figure 2 A schematic process for making a nonwoven fabric comprising an embedded filament layer of reinforcing filaments is shown.

[0054] Figure 3 Different process embodiments for producing the tape core of the present invention are shown. DETAILED DESCRIPTION

[0055] It has been unexpectedly found that by constructing a tape core from one or more layers of impregnated nonwoven fabric (wherein either just one of the impregnated layers also includes just one embedded filament layer containing at least partially reinforcing filaments running in a given filament direction, or where just one filament layer containing at least partially reinforcing filaments running in a given filament direction is sandwiched between two such impregnated layers), a tape cut from such a tape core in such a manner (i.e., the filament direction will form the direction of travel of the tape) has considerable flexibility relative to a tape comprising a woven fabric and other identical constructions. It has been observed that the just one filament layer will tend to form a possible neutral plane for the linearly running tape cut from such a tape core. It has also been found that leaving the remaining impregnated layers without any embedded reinforcing filaments and without any additional reinforcing filaments sandwiched between them will provide the maximum compressibility on the concave side of the tape, and the maximum stretchability on the convex side of the tape, thereby providing maximum flexibility to allow easy bending around a small wheel. It is also found that by embedding this reinforcing filament into the nonwoven fabric of the impregnated layer, or by sandwiching this reinforcing filament between two adjacent impregnated layers each comprising a nonwoven fabric, the above-mentioned longitudinal cutting through the impregnated material of the impregnated layer can be prevented. It is also found that the belt is made of the belt core of the present invention without using any (multiple) woven fabric traction layer together, and these belts provide the toughness comparable to the belt with (multiple) woven fabric traction layer. It is also observed that the belt of the present invention has a reduced noise level during operation while maintaining toughness and resistance to impregnation delamination, which may be attributed to the complete absence of interlaced nodes, which in turn is attributed to the absence of woven fabrics (no "washboard" effect as mentioned in US2008 / 0164127 A1).

[0056] The term "tape core" as used herein refers to a sheet-like layered composite material comprising all the required layers, that is, one filament layer comprising reinforcing filaments and one, two or more impregnation layers each comprising a nonwoven fabric, but the sheet-like layered composite material does not necessarily have the spatial shape of a conveyor belt. A "tape core" as used herein can be cut into one or more belts of appropriate size and width of the present invention, provided that in the case of belts intended for a linear direction of travel (hereinafter also referred to as "linear belts"), the cutting of the (multiple) belts is carried out in such a way that the orientation of the filaments in a single filament layer will form the final intended direction of travel of the (multiple) linear belts thus produced.

[0057] In the tape core of the present invention, the reinforcing filaments form a separate filament layer which is either embedded in a single impregnated layer of nonwoven fabric or sandwiched between two adjacent impregnated layers of nonwoven fabric.

[0058] The reinforcing filaments form a filament layer which is in a plane parallel to the length (y) and width (x) of the tape core of the invention (i.e. the thickness z of the tape core is perpendicular to this plane). If the filament layer is embedded in a nonwoven fabric, the vertical position of the filament layer is preferably within the thickness D of the nonwoven fabric contained therein. mp In the range of 20% to 80%, more preferably in the range of 40% to 60%, wherein D mp The definitions and measurements are as explained herein below. By appropriately selecting the thickness D of the first nonwoven sublayer and the second nonwoven sublayer mp , this vertical position can be easily controlled, and the first nonwoven sublayer and the second nonwoven sublayer can be bonded together by chemical, thermal bonding or mechanical needle punching or bonded by hydraulic entanglement to form a nonwoven fabric with embedded reinforcing filaments, which will also be explained below.

[0059] One filament layer contains "reinforcement filaments" intended to increase the toughness of the tape at least in the direction of travel of the tape. It is envisaged that these reinforcement filaments are preferably neither interlaced nor interwoven with each other and each have one or more subsections, each of which is substantially straight and runs without bends and extends at least partially in a given direction, which will be the direction of travel of the tape in the linear tape cut from the tape core.

[0060] For the purposes of the present invention, the term "extending at least partially in a given direction" shall mean that the quotient r calculated from all reinforcing filaments contained in the entire tape is:

[0061]

[0062] is at least 0.5. In formula (1):

[0063] -L ik (in m) is the length of the kth straight subsegment of the ith filament (e.g., the length of a single edge of a single grid, i.e., the grid size);

[0064] -ρik (in g / m 3 ) is the material density of the kth straight subsegment of the i-th filament;

[0065] - cos(αik) is the cosine of the angle that the kth direct subsegment of the i-th filament has with respect to the one given direction;

[0066] -T ik (in g / m) is the linear density of the kth straight subsegment of the i-th filament;

[0067] - the sum is performed according to k for all K direct sub-segments of the i-th filament; and

[0068] - proceed as i and for all I reinforcing filaments contained in the tape.

[0069] For a layer of reinforcing filaments in the form of one or two arrays of parallel reinforcing filaments (that is, each first filament has only a single straight sub-segment of length L i Corresponding to the total length of the i-th wire), formula (1) is simplified to

[0070]

[0071] in

[0072] -L i (in m) is the entire length of the i-th filament;

[0073] -cos(αi) is the cosine of the angle that the i-th filament has with respect to the one given direction;

[0074] -ρi(in g / m 3 (unit) is the material density of the i-th filament;

[0075] -T i (in g / m) is the linear density of the i-th filament;

[0076] - proceed as i and for all I reinforcing filaments.

[0077] exist Figure 1 a), Figure 1 b) and Figure 1 c) (a transparent top view showing an embodiment of a linear tape cut from a tape core), the "given direction in which the reinforcing filaments extend at least partially" and correspondingly also the direction of travel of the linear tape are indicated by thick arrows.

[0078] Specific reference Figure 1 a): The linear band comprises a filament layer 51 or 52 or 53 in the form of a single array of parallel reinforcing filaments running over the entire length of the parallel reinforcing filaments just in the direction of travel of the band. In the definition of the above formula (2), all cosines are therefore 1 (the angle with the direction of travel of the band is zero), and accordingly r from formula (2) becomes 1, regardless of the filament line density, filament material density and filament length. In addition, I defined for formula (2) divided by the width of the linear band can be considered as the number of reinforcing filaments in the width direction.

[0079] Preferably, Figure 1 In the embodiment of a), all reinforcing filaments are identical.

[0080] Specific reference Figure 1 b): The linear tape comprises a filament layer 51 or 52 or 53 in the form of two arrays of parallel reinforcing filaments, the first array of reinforcing filaments running exactly in the direction of travel of the tape and the second array running exactly perpendicular to the direction of travel of the tape. In the definition of the above formula (2), all cosines of the first array are 1 (angle with the direction of travel of the tape is zero) and all cosines of the second array are 0 (angle with the direction of travel of the tape is 90). Therefore, formula (2) becomes

[0081]

[0082] in

[0083] -L i (in m) is the length of the i-th filament running in the direction of the belt, and ρi (in g / m 3 (in units) is the density of its material;

[0084] -L i (in m) is the length of the jth filament running perpendicular to the direction of the tape travel, ρj (in g / m 3 (in units) is the density of its material;

[0085] -T i and T j (in g / m) are the linear densities of the i-th filament running in the direction of the tape travel and the j-th filament running perpendicular to the direction of the tape travel, respectively;

[0086] - performed as i and for all i reinforcing filaments running in the direction of belt travel;

[0087] - performed as j and for all J reinforcing filaments running perpendicular to the direction of travel of the tape; and

[0088] L i , L j 、T i 、T j , I and J are selected so that r from formula (3) is at least 0.5.

[0089] Here, J divided by the length of the linear tape can be considered as the number of reinforcing filaments in the length direction of the tape, and I divided by the width of the linear tape can be considered as the number of reinforcing filaments in the width direction.

[0090] Alternatively, also refer to Figure 1b): The linear belt may also contain a layer of filaments 51 or 52 or 53 in the form of a square or rectangular grid. In this case, two of the opposite edges of each square or rectangular grid extend exactly in the direction of travel of the belt; all the cosine values ​​of these edges are 1 (their angle with the direction of travel of the belt is zero). The other two opposite edges of each mesh run exactly perpendicular to the direction of travel of the belt; all the cosine values ​​of these other edges are zero (their angle with the direction of travel of the belt is 90°). Therefore, formula (1) becomes:

[0091]

[0092] in

[0093] -L ik (in m) is the length of the kth straight subsegment of the ith filament running in the direction of travel of the tape (e.g., the length of a single edge of a single grid, i.e., the grid size), and ρik (in g / m 3 (in units) is the density of its material;

[0094] -L ik (in m) is the length of the mth straight subsegment of the jth filament running perpendicular to the direction of travel of the tape (e.g., the length of a single edge of a single grid, i.e., the grid size), and ρik (in g / m 3 (in units) is the density of its material;

[0095] -T ik (in g / m) is the linear density of the kth straight subsegment of the i-th filament;

[0096] -T jm (in g / m) is the linear density of the mth straight subsegment of the jth filament;

[0097] - the sum is performed according to k for all K direct subsegments of the i-th filament running in the direction of the tape and completely contained in the tape;

[0098] - performed in m and for all M straight sub-segments of the j-th filament running in a direction perpendicular to the tape and completely contained in the tape;

[0099] - performed as i and for all i reinforcing filaments travelling in the direction of travel of the tape and contained in the entire tape; and

[0100] - This is done as j and for all J reinforcing filaments running perpendicularly to the direction of the tape and contained in the width of the entire tape.

[0101] L ik , L jm , T ik, T jm , I, J, K are selected so that r from formula (4) is at least 0.5.

[0102] Additionally herein, J divided by the length of the tape may be considered the number of filaments in the length direction of the tape, and I divided by the width of the tape may be considered the number of filaments in the width direction.

[0103] exist Figure 1 In the embodiment of b), preferably, all the reinforcing filaments running in the direction of travel of the belt are identical, and all the reinforcing filaments running perpendicularly to the direction of travel of the belt are identical.

[0104] Specific reference Figure 1 c): The linear belt comprises a layer of filaments 51 or 52 or 53 in the form of a grid with diamond-shaped meshes, wherein all mesh edges run in a direction inclined relative to the direction of travel of the belt, at a fixed angle α to the direction of travel of the belt. Thus, formula (1) becomes:

[0105]

[0106] It is independent of line density, material density and edge length, and it must also be at least 0.5.

[0107] Preferably, in this embodiment, each diamond grid has a longer diagonal and a shorter diagonal, wherein the longer diagonal runs in the direction of travel of the belt and the shorter diagonal runs perpendicular to the direction of travel of the belt.

[0108] Specific reference Figure 1 d): In such corner tapes cut circularly from the tape core of the present invention, the filament layer must contain "reinforcement filaments" which increase the toughness in any direction, since the direction of travel is not fixed linear but circular, e.g. Figure 1 d). The local direction of travel at each (x, y) point of the disk or corner strip is a tangent to the circular direction of travel, which is indicated by three thick arrows for three exemplary (x, y) positions. A filament layer in the form of a grid with a square grid is a preferred embodiment here. Figure 1d, the filament layers are aligned in the x (horizontal) and y (vertical) directions. For any (i, k) square grid of this grid, one pair of opposing edges along the x direction will have a fixed angle α relative to the local band travel direction, while the other pair of opposing edges will have a corresponding fixed angle of 90°-α relative to the local band travel direction. Since any (i, k) square grid is always anything from completely parallel to the local band travel direction (α=0°) to completely perpendicular to the local band travel direction (α=90°), the angle α of any (i, k) square grid with the local band travel direction should be measured so that it is always in the range of 0° to 90°. In addition, in the square grid grid, the linear density of all filament edges is equal, so their material density T is equal, so their length ρ is also equal, so L is equal. For each square grid, in order to avoid double counting the number of edges, only one edge in each pair can be considered in the summation. Still further, the product I×J, where I and J are defined as in formula (1), can be considered to be very close to the number of square cells completely contained in the circular band segment. Therefore, the double summation of i and k in formula (1) will be equal to the summation of all square cells completely contained in the circular band segment, where only one edge of each edge pair is considered as required.

[0109] From formula (1) we can get

[0110]

[0111] It is not less than 1.0 for any α in the range from 0 to 90°, and is therefore greater than 0.5, independently of T, L and p.

[0112] for Figure 1 d), the vertical (Y-direction) opposite edges of each grid make an angle α1 of about 35° with the corresponding local belt travel direction, and in the second exemplary position, these edges make an angle α2 of about 30° with the corresponding local belt travel direction. In the third exemplary position, if the measurement α3 is measured so that it is in the range of 0° to 90°, these edges make an angle α3 of about 40° with the corresponding local belt travel direction. Therefore, the corresponding angles of the corresponding horizontal (x-direction) grid edges of the three exemplary positions are 55°, 60° and 50° respectively.

[0113] Each impregnated layer in the belt of the invention preferably consists essentially only of the nonwoven fabric and of the impregnating material and, if applicable, of the reinforcing filaments. "Essentially consisting" in the context of the present invention means that the sum of the weight contents of the nonwoven fabric, the impregnating material and the reinforcing filaments (if present) preferably accounts for at least 97% by weight of the impregnated layer. More preferably, each impregnated layer consists of the nonwoven fabric and the impregnating material and the reinforcing filaments (if present).

[0114] The impregnation material itself is preferably composed mainly of thermoplastics, thermoplastic elastomers, elastomers or thermosetting plastics and optional additives. Additives can be added to the impregnation material, for example, to impart some color (dye or pigment), to act as a filler to improve wear resistance; to increase or reduce CoF (coefficient of friction); to provide flame retardancy; and / or to provide visual (luminescence) and / or metal detectability, or can be added to the function of a plasticizer. The amount of these named additives with a given function can be as high as 75% by weight based on the impregnation material, but is generally in the range of 1 to 25% by weight based on the impregnation material, provided that the type and amount of (multiple) additives are such that the impregnation material can soften or melt at a certain elevated temperature, or otherwise liquefy (e.g., by dissolving or dispersing in a solvent) within at least the time required to impregnate the nonwoven fabric with the softened, melted or otherwise liquefied impregnation material.

[0115] The impregnation material "essentially consists of" a thermoplastic, a thermoplastic elastomer, an elastomer or a thermosetting plastic and optional additives preferably means that the sum of the weight contents of the thermoplastic, thermoplastic elastomer, elastomer or thermosetting plastic and the optional additives discussed above preferably accounts for at least 95% by weight of the impregnation material, whereby the remainder is other unnamed components, such as impurities. More preferably, the impregnation material consists of a thermoplastic, a thermoplastic elastomer, an elastomer or a thermosetting plastic and the optional additives mentioned above.

[0116] The (multiple) nonwoven fabrics used for the core of the present invention are so conventional. They can be made of inorganic fibers, such as glass fibers, basalt fibers, carbon fibers or aramid fibers, in particular. Secondly, they can be made of synthetic organic fibers, such as polyester (such as PET or PBT), polyolefin fibers (such as polypropylene or polyethylene), polyamides (such as nylon-6,6), viscose, polyphenyl sulfone, or bicomponent fibers with high melting point type fibers and low melting point type fibers, or core-sheath fibers with high melting point core and low melting point sheath. The use or co-use of bicomponent fibers (such as in an amount of 50 to 100% by weight based on the total weight of the nonwoven fibers) can improve the tear resistance and elongation resistance (toughness) of the nonwoven fibers, and therefore improve the tear resistance and elongation resistance (toughness) of the belt of the present invention comprising the nonwoven fibers. Thirdly, (multiple) nonwoven fabrics can be made of natural organic fibers, such as wool, cotton, ramie, jute, sisal or flax. If there are multiple nonwoven fabrics in the tape core, it is preferred that the fiber orientation in all nonwoven fabrics is mainly in the same direction. This can be easily achieved by combing the nonwoven fabric before the nonwoven fabric is impregnated and incorporated into the tape core.

[0117] The weight per unit area of ​​any of these nonwoven fabrics is preferably in the range of 50 to 1500 g / m 2 In the range of 50 to 400 g / m 2 within the range.

[0118] The fibers of the nonwoven fabric preferably have a linear density of 3 to 50 dtex, more preferably 5 to 30 dtex, and the density of the fiber material is preferably in the range of 0.9 to 1.3 g / cm 3In the range of . The presence or coexistence of fibers (such as in an amount of 50 to 100% by weight based on the total weight of the nonwoven fibers) and having a titer in the lower part of these ranges (such as in the range of 3 to 20 dtex) can improve the flexibility and elongation resistance (toughness) of the nonwoven fabric, and thus improve the flexibility and elongation resistance (toughness) of the belt of the present invention comprising the nonwoven fabric. On the other hand, the presence or coexistence of fibers (such as in an amount of 50 to 100% by weight based on the total weight of the nonwoven fibers) and having a titer in the higher part of these ranges (such as in the range of 30 to 50 dtex) can improve the tear resistance of the nonwoven fabric, and thus improve the tear resistance of the belt of the present invention comprising the nonwoven fabric. The length of each fiber in the nonwoven fabric or its sublayer is preferably in the range of 15 to 150 mm, more preferably in the range of 30 to 100 mm. This refers to the individual length of each fiber, not the average length of all fibers. Thus, substantially all, ie at least 95%, of the fibre sample are intended to have such a length.The weight ratio of nonwoven fabric to impregnation in the impregnation layer(s) is preferably in the range of 30:70 to 80:20.

[0119] In the context of the present invention, the thickness D of any geometrically well-defined layer or sheet (which includes any isolated impregnated layer(s) and the entire tape core of the present invention) is measured directly on that layer or sheet and is then designated as D m The thickness D of the tape core of the present invention is m It is preferably in the range of 0.3 to 5 mm, more preferably in the range of 0.4 to 2 mm.

[0120] The thickness of any nonwoven fabric or nonwoven sublayer is determined under a certain overpressure (i.e., above atmospheric pressure) applied perpendicularly to the surface of the nonwoven fabric. For example, this overpressure can be applied by the measuring instrument itself, or by an additional mold that compresses the sheet layer or the nonwoven fabric. In order to measure the thickness of the nonwoven fabric or its sublayer itself, the overpressure can be selected to be 0.2 bar. However, in order to define the correct amount of impregnation material to be used, the overpressure applied in the thickness measurement will be the same as the overpressure used in the corresponding impregnation step using heat and pressure (see below). The thickness measured under a certain applied pressure is designated as D in the following text. mp .

[0121] Preferably, the amount of impregnation material is such that only the void spaces in the nonwoven fabric are expelled, so that the nonwoven fabric is completely filled with the impregnation material, but on the other hand, no excess impregnation material is used that would form in the finished core area or layer without nonwoven fabric. This requires taking into account the overpressure applied in any impregnation step, because the thickness D of the nonwoven fabric before impregnation or when impregnated with the molten or otherwise liquefied impregnation material. mpStrongly dependent on the pressure.

[0122] In order to correctly select the required volume of impregnation material, the following formula (7) is indicated:

[0123]

[0124] in:

[0125] -A (in m 2 (in units) is the geometric surface of the impregnation layer(s) to be prepared;

[0126] - w D mp (in m) is the thickness of the wth nonwoven fabric measured at the same overpressure applied during impregnation. If heat and pressure are used for impregnation, this is used to measure w D mp The overpressure should be the same as that used during the heat and pressure impregnation. Alternatively, if an aqueous dispersion of the impregnation material is used for impregnation, the overpressure used to measure w D mp The overpressure should be only 0.2 bar;

[0127] - w W (in g / m 2 (unit) is the weight per unit area of ​​the w-th nonwoven fabric;

[0128] -wρ(in g / m 3 ) is the density of the fiber material of the wth nonwoven fabric at the temperature used in the impregnation;

[0129] - the sum of w is carried out for all nonwoven fabrics to be used;

[0130] - s V (in m 3 The volume of the sth impregnation material to be used at the temperature used in the impregnation (in units); and

[0131] - Perform the sum of the steps performed for all S impregnation materials used.

[0132] Therefore, if a one-step impregnation / bonding of several nonwoven fabrics is chosen to form the tape core of the present invention in a single step, then A above will also be the geometric surface of the tape core to be formed.

[0133] Alternatively, if sequential stacking is chosen, the above formula (7) applies only to one nonwoven fabric and one impregnation material to be used in one sequential impregnation / stacking step. W and S are equal to 1.

[0134] Exemplary thermoplastics or thermoplastic elastomers for the impregnation material can be selected from one of the generally known subgroups: i) styrene block copolymers (TPE-s), ii) thermoplastic (co)polyolefins and their blends (TPO), iii) elastomeric alloys (TPE-v or TPV), iv) thermoplastic polyurethanes (TPU), v) thermoplastic copolyesters and vi) thermoplastic polyamides.

[0135] Exemplary elastomers for impregnating materials are natural rubber, polyisoprene, polybutadiene, styrene-butadiene rubber (SBR), nitrile rubber (NBR), ethylene propylene diene monomer (EPDMP), polyurethane and acrylate rubber. Preferably, when used as an impregnating material, the elastomer is not yet vulcanized or crosslinked, but can be vulcanized or crosslinked during the impregnation step, particularly when heat and pressure are used. For this reason, the elastomer may contain an appropriate amount of premixed vulcanizing agent. In order to calculate the amount of weight in the impregnated layer, this vulcanizing agent will be considered as an optional additive with a given function.

[0136] Exemplary thermosetting materials for impregnating materials are polymers or resins that crosslink and cure when heated, rather than the above-mentioned elastomers. Examples are adducts of phenol / cresol formaldehyde (novolac) with epoxy resins (such as epichlorohydrin), urea / formaldehyde resins, melamine resins, silicone resins, polyimides, bismaleimides and benzoxazines. These resins are preferably used for uncured A-stage or partially cured B-stage, with care being taken that no C-stage curing occurs during the impregnation process. The molecular weight of the starting resin and the degree of curing should preferably be controlled so that the cured resin is still sufficiently flexible.

[0137] On the one hand, more preferred are TPUs (such as those prepared from 1) by reacting an aromatic diisocyanate (such as isomeric 2,2'-, 2,4'- or 4,4'-diphenylmethane diisocyanate) with an aliphatic chain extender (e.g., a C2-C6-diol such as ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-propylene glycol, 2-methylpropylene glycol, 1,3-butanediol, 2,3-butanediol, 1,3-pentanediol, 1,2-hexanediol and 3-methylpentane-1,5-diol; or a glycol ether such as diethylene glycol, dipropylene glycol and tripropylene glycol). and amino alcohols, such as ethanolamine, N-methyldiethanolamine) hard segments and 2) those made of aliphatic polyester polyols or polyether polyols as soft segments) or TPO (such as those selected from the following: ii-1) homopolymers and copolymers of vinyl monomers having the structure XHC=CH2, wherein X is selected from chlorine, acetoxy, phenyl and cyano, and the comonomer (for copolymers) is ethylene and / or propylene; and ii-2) ethylene-α-olefin copolymers, wherein the α-olefin is preferably selected from propylene, 1-butene, 1-hexene, 1-heptene and 1-octene).

[0138] In one embodiment, all impregnation layers of the tape core of the invention comprise the same impregnation material, which preferably also comprises a thermoplastic or a thermoplastic elastomer, in particular TPU.

[0139] The preparation of the tape core of the present invention can be carried out in several ways, as shown below. Figure 1 , Figure 2 and Figure 3 Three preferred ways are illustrated. These figures show a preferred way of impregnating a nonwoven fabric using a preformed impregnation material sheet. However, in the following description, other impregnation methods will be mentioned as alternatives whenever possible.

[0140] Generally speaking, for Figure 3 Any hatching from lower left to upper right indicates a cross section through a sheet of impregnating material, any hatching from upper left to lower right indicates a cross section through a nonwoven fabric, and any bidirectional hatching indicates an area or layer of the nonwoven fabric that has been or is being impregnated with an impregnating material. Any thick vertical arrow indicates the use of heat and pressure bonding.

[0141] Figure 3 A first variant i) of the invention (claim 12) illustrates a method in which exactly one layer 51 of filaments embedded in one impregnation layer 21 is used. This variant comprises the following steps:

[0142] Step i-1): First, a first nonwoven sublayer 31, a second nonwoven sublayer 32 and a filament layer 51 comprising reinforcing filaments extending at least partially in a given direction are provided. The two sublayers 31, 32 comprise the fibers applicable to nonwoven fabrics described above, and are therefore conventional. They may optionally be combed to impart a more uniform fiber orientation, preferably such that the fiber orientations in the two sublayers 31, 32 are identical. The reinforcing filaments are pre-oriented such that they are at least partially oriented in a given direction, or are directly provided with such orientation.

[0143] Steps i-2) and i-3) are also referred to Figure 2 , the filament layer 51 is arranged, in particular laid on top of the second nonwoven sublayer 32, and the first nonwoven sublayer 31 is arranged on top of the filament layer 51. The first nonwoven sublayer 31, the filament layer 51 and the second nonwoven sublayer 32 are pressed together, for example using two compression rollers 91, 92. Then, they are joined together, for example and preferably by needle punching, such as Figure 2As shown by a needle punching device 10. Alternatively, they can be bonded together by chemical means (thermosetting adhesives), thermal bonding (hot melt adhesives) or mechanical methods (stitching or otherwise mechanically bonding together), or by so-called hydroentanglement. Needle punching or hydroentanglement also randomizes the direction of the nonwoven fibers in the z direction (orthogonal to the length (y) and width (x) of the nonwoven fabric).

[0144] In step i-4), the first nonwoven fabric 3 is impregnated with a first impregnation material 4, which includes or consists essentially of a first thermoplastic, a first thermoplastic elastomer, a first elastomer or a first thermosetting plastic and the optional additives outlined above, to form a first impregnation layer 21 with an embedded filament layer 51. This impregnation step can be performed using a calender or extruder using a preformed sheet of the first impregnation material (e.g. Figure 3 As shown in Figure 3, the first impregnation material is preferably used as a first impregnation material. The first impregnation material may be ...

[0145] In step i-5), there are two sub-variants: the first sub-variant, including steps i-5-a) to i-5-c) (not in Figure 3 shown in , but similar to Figure 3 Embodiment ii) shown in , and the second sub-variant includes steps i-5-d) to i-5-e).

[0146] In the first sub-variant, step i-5-a) is to provide one or more other nonwoven fabrics and one or more other sheets of other impregnating materials, which each include or are substantially composed of other thermoplastics, other thermoplastics, other elastomers or other thermosetting plastics and optional additives, as illustrated above. Since there is only one layer of reinforcing filaments in the whole core, and these reinforcing filaments have been introduced in steps i-2) and i-3), any such other nonwoven fabric does not have reinforcing filaments. The total volume of the impregnating material provided by the other sheets, the weight per unit area of ​​each nonwoven fabric and the thickness D mpAnd the material density is preferably selected so that the total void volume of all additional nonwoven fabrics can be filled with impregnated material, but without forming areas or layers without nonwoven fabrics (see calculation using formula (7) above). In one embodiment, this may mean that the number of additional nonwoven fabrics is equal to the number of additional sheets, but this is not necessarily the case.

[0147] Step i-5-b) is to arrange the one or more additional nonwoven fabrics and the one or more additional sheets adjacent to the first impregnation layer 21 and adjacent to each other, so that there is at least one additional sheet adjacent to any nonwoven fabric, and at least one additional nonwoven fabric adjacent to any additional sheet. This helps to uniformly and completely impregnate the nonwoven fabric with the impregnation material from at least one adjacent sheet. The total number of additional sheets, the total volume of impregnation material they provide, and the unit area weight and thickness D of all additional nonwoven fabrics. mp The material density is preferably selected so that the total void volume of all the additional nonwoven fabrics on one side of the first impregnation layer 21 can be filled with the impregnation material (see calculation using the above formula (7)). Similarly, the total number of additional sheets, the total volume of impregnation material they provide, and the unit weight and thickness D of all the additional nonwoven fabrics are mp The material density is preferably selected so that the total void volume of all additional nonwoven fabrics on the other side of the first impregnation layer 21 can be filled with impregnation material. Here again, this means that on each of the two sides of the first impregnation layer 21, the number of sheets and nonwoven fabrics is equal.

[0148] In step i-5-c), any additional nonwoven fabric is impregnated with the impregnation material from at least one additional sheet immediately adjacent to the nonwoven fabric, using heat and pressure. This usually means using a calender, hot press or drum vulcanizer. The applied overpressure is preferably at D mpThe overpressure used in the above-mentioned determination of.It is also to melt the resin in thermoplastic, thermoplastic elastomer or B stage by heat and pressure simultaneously impregnation and combining together, rather than simply to carry out at a sufficiently high temperature of softening.Only when the impregnation material is basically molten, it has a sufficiently low viscosity to penetrate all gaps in adjacent (multiple) nonwoven fabrics, thereby forming an impregnation layer."basically molten" can preferably represent in the context of the present invention that the melt has at least 20g / 10min, preferably at least 30g / 10min and most preferably 30 to 60g / 10min MFI at 8.7kg under the selected impregnation temperature.In each case, condition is that temperature keeps sufficiently low, to avoid impregnation material decomposition, and, if thermosetting plastic is used in the impregnation material, then impregnation is not more than the B stage when the thermosetting plastic is solidified, rather than being substantially complete in the C stage.

[0149] In the step i-5-d) of the second sub-variation, directly provide one or more other preformed impregnated layers 22,23,24,25, these one or more other preformed impregnated layers each comprise or are made up of other nonwoven fabrics utilizing other impregnated material impregnation, this impregnated material comprises or is basically made up of other thermoplastic, other thermoplastic elastomer, other elastomer or other thermosetting plastic and optional additive, as outlined above.These can be preformed by corresponding nonwoven fabric and impregnated material by any process outlined above for step i-4).Because in whole band core, only one deck is strengthened filament, and these strengthened filaments have been introduced in step i-2) and i-3), therefore any this other impregnated layers 22,23,24,25 do not have strengthened filament.

[0150] In step i-5-e), one or more additional impregnation layers 22, 23, 24, 25 are arranged adjacent to the first impregnation layer 21 and adjacent to each other; and any such additional impregnation layers 21, 22, 23, 24, 25 and the first impregnation layer 21 are bonded together under heat and pressure. The conditions and apparatus may be as outlined above under step i-5-c). If the impregnation(s) consist of an impregnation material comprising a thermosetting plastic in the A-stage or B-stage, curing to the final C-stage may be allowed to occur here.

[0151] In step i-5), the number of nonwoven fabrics (first sub-variant) or the number of impregnated layers (second sub-variant) present on each side of the first impregnated layer 21 is preferably chosen so that the first impregnated layer 21 containing the embedded layer of filaments 51 will preferably be close to or at the neutral plane of the linear tape cut from the tape core once the tape will be in use. This means, for example, that for a linear tape that always has the same tape surface facing all wheels, the first impregnated layer will preferably be at the inner concave side of the tape and will face the wheels, while all the other impregnated layers 22, 23, 24, 25 will preferably be arranged on the outside of the first impregnated layer 21 and will face away from the wheels.

[0152] Figure 3 A second variant ii) of (claim 13) illustrates a method in which the tape core 1 is formed using exactly one filament layer 52 sandwiched between two impregnation layers 21, 22. This variant comprises the following steps:

[0153] In step ii-1), a first nonwoven fabric 301 is provided; a second nonwoven fabric 302; a first sheet 401 of a first impregnating material, the first impregnating material comprising or essentially consisting of a first thermoplastic, a first thermoplastic elastomer, a first elastomer or a first thermosetting plastic and the above-mentioned optional additives; a second sheet 402 of a second impregnating material, the second impregnating material comprising or essentially consisting of a second thermoplastic, a second thermoplastic elastomer, a second elastomer or a second thermosetting plastic and the above-mentioned optional additives; and reinforcing filaments in the form of a filament layer 52 extending at least partially in a given direction. The reinforcing filaments are pre-oriented so that they are at least partially oriented in a given direction, or are directly provided with such an orientation. Preferably, the total volume of the impregnating materials provided by the first sheet 401 and the second sheet 402 and the unit area weight and thickness D of the two nonwoven fabrics 301, 302 are mp and the material density are selected such that the total void volume of the two nonwoven fabrics 301 , 302 can be filled with the impregnation material (see calculation using the above formula (7)).

[0154] In step ii-2), the filament layer 52, the first nonwoven fabric 301 and the second nonwoven fabric 302 and the first sheet 401 and the second sheet 402 are arranged adjacent to each other, so that there is at least one first nonwoven fabric 301 and at least one first sheet 401 on one side of the filament layer 52, and at least one second nonwoven fabric 302 and at least one second sheet 402 on the other side of the filament layer 52, so that the filament layer 52 is sandwiched between the first nonwoven fabric 301 and the first sheet 401 on the one hand, and between the second nonwoven fabric 302 and the second sheet 402 on the other hand; to form a layered composite material 6. Preferably, the first sheet 401 and the second sheet 402 face the filament layer 52, and the first nonwoven fabric 301 and the second nonwoven fabric 302 are sandwiched in the combination of the first sheet 401 / filament layer 52 / second sheet 402, and the total volume of the impregnated material provided by the first sheet 401 and the second sheet 402 and the unit area weight and thickness D of the two nonwoven fabrics 301, 302 are mp And the material density is selected so that the total void volume of the two nonwoven fabrics 301, 302 can be filled with the impregnation material from the first and second sheets 401, 402 (see calculation using the above formula (7)). This ensures that the filament layer 52 is surrounded and remains surrounded by the molten impregnation material during the subsequent impregnation / bonding step ii-3-c) using heat and pressure, and thus avoids the filament layer 52 being distorted or damaged by any adjacent nonwoven fabrics.

[0155] In step ii-3), there are two sub-variants: a first sub-variant including steps ii-3-a) to ii-3-c), and a second sub-variant including steps ii-3-d) to ii-3-f).

[0156] In a first sub-variant, step i-3-a) is optionally providing one or more additional nonwoven fabrics 303, 304, 305 and one or more additional sheets 403, 404, 405 of additional impregnation material, the additional impregnation material comprising or consisting essentially of additional thermoplastics, additional thermoplastics, additional elastomers or additional thermosetting plastics and optional additives, as outlined above (e.g. Figure 3 The total number of additional sheets 403, 404, 405, the total volume of impregnated material they provide, and the weight per unit area and thickness D of all additional nonwoven fabrics 303, 304, 305 are shown directly in FIG. mpThe material density is preferably selected such that the total void volume of all additional nonwoven fabrics 303, 304, 305 can be filled with the impregnation material (see calculation using the above formula (7)). This may mean that the number of additional nonwoven fabrics 303, 304, 305 is equal to the number of additional sheets 403, 404, 405, but this is not necessarily the case.

[0157] In step ii-3-b), optional one or more other nonwoven fabrics 303,304,305 and one or more other sheets 403,404,405 are arranged to adjacent step ii-2) layered composite 6 and adjacent to each other, so that there is at least one other sheet next to any nonwoven fabric, and there is at least one other nonwoven fabric next to any other sheet. This helps to impregnate the nonwoven fabric evenly and completely by the impregnation material from at least one adjacent sheet.Preferably, on each side of the layered composite material 6, the quantity of other nonwoven fabrics equals the quantity of other sheets.

[0158] In step ii-3-c), use heat and pressure, use heat and pressure respectively, and impregnate any nonwoven fabric 301 or 302 or 303 or 304 or 305 by impregnation from at least one other sheet material next to nonwoven fabric 401 or 402 or 403 or 404 or 405, to form corresponding impregnation layer 21 or 22 or 23 or 24 or 25 respectively; And all such impregnation layers 21, 22, 23, 24, 25 and described layered composite material 6 are combined together. Conditions and devices can be as outlined above under step i-5-c). If (multiple) impregnations are composed of impregnation materials including thermosetting plastics in A-stage or B-stage, then curing to final C-stage can be allowed to occur here.

[0159] In a second sub-variant, step ii-3-d) optionally provides one or more additional impregnation layers, each additional impregnation layer comprising or consisting of an additional nonwoven fabric impregnated with an additional impregnation material, each of which comprises or essentially consists of an additional thermoplastic, an additional thermoplastic, an additional elastomer or an additional thermosetting plastic and optional additives (as outlined above), and without reinforcing filaments. This sub-variant is not directly shown in Figure 3 ii), but similar to providing Figure 3 The impregnated further layers 22, 23, 24, 25 of variant i) are shown in FIG. These optional further impregnated layers 22, 23, 24, 25 may be prepared beforehand by any of the processes outlined above for step i-4).

[0160] Step ii-3-e) is to arrange one or more optional additional impregnation layers 22, 23, 24, 25 adjacent to the layered composite material 6 of step ii-2) and adjacent to each other; and in step ii-3-f), any such optional additional impregnation layers 21, 22, 23, 24, 25 and the layered composite material 6 are combined together using heat and pressure. The conditions and apparatus may be as outlined above under step i-5-c). If the (multiple) impregnations consist of an impregnation material comprising a thermosetting plastic in the A-stage or B-stage, curing to the final C-stage may be allowed to occur here.

[0161] As in step i-5) above, in step ii-3), for the reasons outlined above under step i-5), the number of additional nonwoven fabrics (first sub-variant) or the number of additional impregnated woven fabrics (second sub-variant) arranged on each side of the layered composite material 6 is selected so that the filament layer 52 is in or close to a neutral plane for the finished tape and the intended end use of the tape.

[0162] Figure 3 A third variant iii) (claim 14) illustrates a method in which the core 1 is formed using exactly one filament layer 53 sandwiched between two impregnation layers 22, 23, and the core is built sequentially until the desired number of impregnation layers or the desired core thickness is obtained. This variant allows the direct formation of an annular core of the invention, since the first impregnation layer 21 and then the bonded layered composite material 7 can be formed into an annular loop, onto which the subsequent impregnation layers are wound and bonded. This third variant comprises the following steps:

[0163] In step iii-1), reinforcing filaments in the form of a filament layer 53 extending at least partially in a given direction, and a first impregnated layer 21 are provided, the first impregnated layer 21 comprising or consisting of a first nonwoven fabric, the first nonwoven fabric being impregnated with a first impregnating material, the first impregnating material comprising or substantially consisting of a first thermoplastic, a first thermoplastic elastomer, a first elastomer or a first thermosetting plastic and an optional additive composition (as outlined above), but without reinforcing filaments. The reinforcing filaments are pre-oriented so that they are at least partially oriented in a given direction, or are directly provided with such orientation. The impregnated layer 21 can be prepared in advance by any one of the processes described in the above step i-4), provided that the nonwoven fabric used does not have reinforcing filaments.

[0164] In step iii-2), there are two sub-variants: a first sub-variant including steps iii-2-a) to iii-2-d), and a second sub-variant including steps iii-2-e) to iii-2-h).

[0165] In the first sub-variant, step iii-2-a) is to provide one or more additional nonwoven fabrics 306, 307, 308 and one or more additional sheets 406, 407, 408 of additional impregnation material, which includes or is substantially composed of additional thermoplastics, additional thermoplastic elastomers, additional elastomers or additional thermosetting plastics and optional additives, as outlined above. Here, the number of additional nonwoven fabrics 306, 307, 308 must be equal to the number of additional sheets 406, 407, 408, because the belt is sequentially constructed, wherein each construction cycle uses exactly one additional nonwoven fabric 306, 307, 308 and exactly one additional sheet 406, 407, 408 to form a continuous additional impregnation layer adhered to the bonded layered composite material 7. This number is an integer designated as K, which must be at least 1 and can be arbitrarily high. However, preferably, K is in the range of 1 to 5.

[0166] In step iii-2-b), one of the further nonwoven fabrics 306, one of the further sheets 406 and optionally the filament layer 53 are arranged on one side of the first impregnation layer 21 and adjacent thereto, so that if a filament layer 53 is provided, it is sandwiched between the first impregnation layers 21 on the one hand and is sandwiched between the further nonwoven fabric 306 and the further sheet 406 on the other hand. Preferably, the volume of the impregnation material provided by the further sheet 406 and the weight per unit area and the thickness D of the further nonwoven fabric 306 are 200 μm and 200 μm, respectively. mp And the material density is selected so that the void volume of the further nonwoven fabric 306 can be filled with the impregnation material from the further sheet 406 (see calculation using the above formula (7)). Preferably, the optional filament layer 53 is clamped so that there is a first impregnation layer 21 on one side of the filament layer 53 and a further sheet 406 on the other side, and the further nonwoven fabric 306 is on the further sheet 406 and faces away from the filament layer 53. This ensures that during the simultaneous impregnation and adhesion step iii-3-c) using heat and pressure (see immediately below), the filament layer 53 is surrounded by the softened impregnation material and remains surrounded by the softened impregnation material, and thus avoids the filament layer 53 being distorted or damaged by any adjacent nonwoven fabric.

[0167] In step iii-2-c), the further nonwoven fabric 306 is impregnated with the impregnation material from the further sheet 406 simultaneously using heat and pressure to form a further impregnation layer 22, and the first impregnation layer 21, the optional sandwiched filament layer 53 and the further impregnation layer 22 are bonded together; to form a bonded layered composite material 7. The conditions and apparatus may be as outlined above under step i-5-c).

[0168] Step iii-2-d) is to repeat the above steps iii-2-b) and step iii-2-c) K-1 times for the combined layered composite material 7 using further pairs 307 / 407, 308 / 408 of further nonwoven fabrics and further sheets of further impregnation material, provided that in steps iii-2-b) and step iii-2-c) and in said repetition of said steps, the filament layer (53) is used exactly once in total. Preferably, the volume of impregnation material provided by each further sheet 407, 408 and the weight per unit area and thickness D of each corresponding further nonwoven fabric 307, 308 are mp And the material density is selected so that the void volume of each additional nonwoven fabric 307, 308 can be filled with the impregnation material from the corresponding additional sheet 407, 408 (see calculation using the above formula (7)). Here again, if in any repetition of steps iii-2-b) and iii-2-c), a filament layer 53 is used, the optional filament layer 53 is preferably clamped so that there is a combined layered composite material 7 on one side of the filament layer 53, and on the other side there is an additional sheet 407 or 408, and the additional nonwoven fabric 306 or 307 is on the additional sheet 407 or 408 and facing away from the filament layer 53. The reasons for this layer ordering are as given above for step iii-2-b). Performing K-1 repetitions may mean zero repetitions because K is at least 1. In the case where K=1, the filament layer 53 must have been used in steps iii-2-b) and iii-2-c).

[0169] After step iii-2-c) (if K=1) or during the last repetition of steps iii-2-b) and iii-2-c (if K>1), if the (multiple) impregnations consist of an impregnation material comprising a thermosetting plastic in the A-stage or B-stage, curing to the final C-stage can be allowed to occur here.

[0170] In a second sub-variant, step iii-2-e) provides one or more further impregnated layers 22, 23, 24, 25, each of which comprises or consists of a further nonwoven fabric impregnated with a further impregnating material, each of which comprises or consists essentially of a further thermoplastic, a further thermoplastic elastomer, a further elastomer or a further thermosetting plastic and optional additives (as outlined above). This sub-variant is not directly shown in Figure 3 iii), but similar to providing Figure 34). The further impregnation layers 22, 23, 24, 25 of the variant i) shown in FIG. These further impregnation layers 22, 23, 24, 25 can be prepared in advance by any of the processes outlined above for step i-4). All these further impregnation layers are also free of reinforcing filaments, since the tape comprises only one layer of reinforcing filaments in total, i.e. the filament layer 53. The number of further impregnation layers provided is again designated K, which is an integer that must be at least 1 and can be arbitrarily high. Preferably, however, K is in the range of 1 to 5.

[0171] In step iii-2-f), a further impregnation layer 22 is arranged on one side of the first impregnation layer 21 and adjacent thereto, so that if a filament layer 53 is also provided, the filament layer 53 is sandwiched between the first impregnation layers 21 on the one hand and by the second impregnation layer 22 on the other hand.

[0172] In step iii-2-g), the first impregnated layer 21, the optional sandwiched filament layer 53 and the further impregnated layer 21 are bonded together using heat and pressure; to form a bonded layered composite material 7. The conditions and apparatus may be as outlined above under step i-5-c).

[0173] Step iii-2-h) is to repeat the above steps iii-2-f) and step iii-2-g) K-1 times for the combined layered composite material 7, using one of the further impregnation layers 23, 24, 25 in each repetition, as long as in steps iii-2-f) and iii-2-g) and in the repetition of the steps, the filament layer 53 is used exactly once in total. This is also considering that there is only one layer of reinforcing filaments in the entire belt, which is the filament layer 53. Performing K-1 repetitions may mean zero repetitions, because K is at least 1. In the case of K=1, the filament layer 53 must have been used in steps iii-2-f) and iii-2-g). After step iii-2-g) (if K=1) or during the last repetition of steps iii-2-f) and iii-2-g (if K>1), if (multiple) impregnations consist of an impregnation material comprising a thermosetting plastic in the A-stage or B-stage, curing to the final C-stage can be allowed to occur here.

[0174] exist Figure 3 In the third variant iii), the filament layer 53 is preferably used in the sequential construction step, which will provide a clamped filament layer 53 which, during its use, is close to or in the neutral plane of the linear tape cut from the tape core for the reasons outlined under step i-5) above.

[0175] In all process variants of the invention, the orientation of the filaments present in the initial filament layers 51, 52, 53 will constitute the longitudinal direction of the tape, i.e. the direction of travel of the tape. This means that if a tape formed according to the invention needs to be cut to size so that the two lateral sides are spaced apart by the desired tape width, then such lateral side cutting must be done so that it is parallel to said filament orientation, which will form the direction of travel of the tape.

[0176] exist Figure 3 In all three variants i), ii) and iii) of the invention, the adjacent layers are bonded together by heat and pressure or without the common use of an adhesive. This is particularly possible if the impregnations to be bonded together are made of chemically compatible thermoplastics or thermoplastic elastomers. Alternatively, an adhesive or a primer can be used to bond two chemically incompatible impregnations together.

[0177] The belt core of the present invention is suitable for cutting, stamping or punching out a linear conveyor belt, machine belt, power transmission belt or spindle belt with a given length and width. It is also suitable for cutting, stamping or punching out a rotating conveyor disc or corner belt. In the case of a linear belt, the cutting should be carried out so that the given direction on which the reinforcing filaments in the filament layer of the belt core of the present invention extend at least partially should be or become the longitudinal travel direction of the linear belt. Here, the shape of the filament layer can be any such shape, provided that the reinforcing filaments satisfy the above equation (1). For a disc or a corner belt, it seems preferred that the belt core comprises a filament layer in the form of a grid of a square grid.

[0178] The core of the present invention or the belt or disc obtained therefrom may optionally be further coated with a top covering layer, thereby imparting to the belt or core appropriate advantageous properties, such as chemical resistance, antibacterial properties, hydrophobicity, different friction coefficients or a combination of these properties. This top covering layer may preferably be adhered to the core or the belt obtained therefrom using a thermosetting (cross-linking) adhesive compatible with the materials to be bonded together, such as polyurethane, rubber, rubber mixtures and phenolic resins. As an alternative or in addition, the surface of the outermost impregnated layer of the core or belt (the surface that will face the goods to be transported) may be provided by embossing or surface contours, which impart the surface properties required for the corresponding application, in particular adhesion and / or friction properties. Such embossing or contouring is particularly required to provide discrete longitudinally running surface segments with different static friction coefficients, which are arranged adjacent to each other in the transverse direction of the belt. Thus, the application of such top covering layers and contours or embossing is conventional and well known to those skilled in the art.

[0179] The tapes of the present invention may be made endless using any end joining technique known in the art, such as mechanical joining or finger joining techniques, or using one or more of the thermoplastic or thermoplastic elastomeric materials from the impregnated layers as or in conjunction with the hot melt adhesive.

[0180] The belts of the present invention may be used in any conveying application where prior art belts have been used, such as conveyor belts, machine belts, power transmission belts or spindle belts.

[0181] However, a first preferred application is a so-called "conveyor belt". This is a belt that transports goods from one first main belt to another main belt that is adjacent but not in close proximity to the first main belt. For this purpose, the conveyor belt is usually mounted on transport supports at both ends in the form of so-called "transfer tails" (these transfer tails are belt turning points with wheels of very small diameter on their top sides), or even just on pressure bars, in order to allow the conveyor belt to transport goods until very close to and to the main conveyor belt.

[0182] The second preferred application is the so-called "corner tape". This is an application in which a round tape is cut from the tape core of the invention (as a circular arc segment with a given segment angle β) and the ends of the circular arc segment are joined to form an annular corner tape. The finished corner tape will have a circular tape travel direction moving along the arc in use, and its path length will be close to the arc radius multiplied by β / 2. That is, for example, cutting a circular arc segment with β=π (=180°) and a given radius r from the tape core and joining the ends will provide a circular corner tape with a path length close to π / 2*r. For this application, the tape core of the invention will preferably contain a filament layer in the form of a net with a square grid.

Claims

1. A belt core (1), comprising one, two or more than two impregnation layers (21, 22, 23, 24, 25); characterized in that: i. Each impregnation layer (21, 22, 23, 24, 25) comprises a nonwoven fabric (3, 301, 302, 303, 304, 305, 306, 307, 308) and an impregnation material (4, 401, 402, 403, 404, 405, 406, 407, 408), or is substantially composed of the nonwoven fabric (3, 301, 302, 303, 304, 305, 306, 307, 308) and the impregnation material (4, 401, 402, 403, 404, 405, 406, 407, 408), the impregnation material comprises a first thermoplastic, a first thermoplastic elastomer, a first elastomer or a first thermosetting plastic and optional additives, or the impregnation material basically consists of a first thermoplastic, a first thermoplastic elastomer, a first elastomer or the first thermosetting plastic and optional additives, whereby, in the case of having two or more impregnation layers (21, 22, 23, 24, 25), the impregnation layers are adjacent to each other, ii. In the case where the core (1) comprises one or more impregnation layers (21, 22, 23, 24, 25), reinforcing filaments extending at least partially in a given direction and in the form of a filament layer (51) are embedded in the nonwoven fabric (3) of exactly one impregnation layer in the impregnation layers (21); or In case the tape core (1) comprises two or more of the impregnation layers (21, 22, 23, 24, 25), reinforcing filaments extending at least partially in one given direction and in the form of exactly one filament layer (52, 53) are sandwiched between two adjacent impregnation layers (21 / 22, 24 / 25), and iii. The belt core has no woven fabric.

2. The tape core (1) according to claim 1, wherein: Each nonwoven fabric is completely filled with the impregnation compound.

3. The belt core (1) according to claim 1 or 2, characterized in that: The filament layer (51) is embedded in one or more of the nonwoven fabrics of exactly one of the impregnated layers (21), and the tape core (1) comprises 1 to 8 impregnated layers (21, 22, 23, 24, 25).

4. The belt core (1) according to claim 1 or 2, characterized in that: The filament layers (52, 53) are sandwiched between two adjacent impregnation layers (21 / 22, 24 / 25), and the tape core (1) comprises 2 to 8 impregnation layers (21, 22, 23, 24, 25).

5. The tape core (1) according to any one of claims 1 to 4, wherein: The filament layer (51, 52, 53) comprises reinforcement filaments in the form of a first array of parallel reinforcement filaments.

6. The tape core according to claim 5, wherein: The layer of filaments (51, 52, 53) further comprises a second array of parallel reinforcing filaments extending perpendicularly to the filaments of the first array.

7. The tape core (1) according to any one of claims 1 to 4, wherein: The filament layers (51, 52, 53) are in the form of a grid of reinforcing filaments having a square or rectangular grid.

8. The tape core (1) according to any one of claims 1 to 4, wherein: The filament layers (51, 52, 53) are in the form of a grid having diamond-shaped meshes.

9. A conveyor belt core (1) according to any one of claims 1 to 8, characterized in that All impregnation layers (7, 21, 22, 23, 24, 25) contain the same impregnation material, or are characterized in that The impregnation layers (7, 21, 22, 23, 24, 25) contain different impregnation materials.

10. A linear belt, which can be obtained from a belt core according to any one of claims 1 to 9 by cutting a linear belt of desired width and length from the belt core, so that the one given direction is in the length direction of the cut linear belt, wherein the reinforcing filaments extend at least partially along the one given direction, wherein the linear belt is particularly a transmission belt, a conveyor belt, a machine belt, a power transmission belt or a spindle belt.

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