Fibre composite material made of at least one tape

Abstract

The invention relates to a fibre composite material which is made of at least one tape having a width of 30 mm. The tape comprises at least two hybrid rovings, wherein each hybrid roving comprises at least one layer of reinforcing fibres and at least two layers of thermoplastic fibres. The at least two hybrid rovings are arranged in the tape next to one another and so as to abut one another, without overlapping, transversely to the main propagation direction of the reinforcing fibres. Each hybrid roving has a width transverse to the orientation of the fibre of at least 15 mm and the reinforcing fibres of the hybrid roving are not twisted in the fibre composite material. The invention also relates to a method for producing the fibre composite material, and to the tape itself.

Description

[0001] Fiber composite material made of at least one tape

[0002] Description:

[0003] The invention relates to a fiber composite material made from at least one tape composed of at least two hybrid rovings. Furthermore, the invention relates to a method for producing the fiber composite material and a tape composed of hybrid rovings.

[0004] Hybrid rovings are already known. For example, such hybrid rovings are described in EP 3638492. However, fiber composites made from these hybrid rovings often have mechanical properties that are not homogeneous within the fiber composite. Furthermore, the production of fiber composites from the known hybrid rovings is complex because a large number of hybrid rovings must be unwound and processed via creels. DE 10 2014 019 220 D1 describes a method for producing a bath-shaped semi-finished product. For example, matrix fiber bundles are spread out together with reinforcement fiber bundles and laid on top of one another. The width of the fiber bundles should be between 6 mm and a maximum of 16 mm, and in a three-layer structure, adjacent fiber bundles overlap one another.

[0005] The object of the present invention was therefore to provide a fiber composite material comprising at least one tape, wherein the at least one tape is formed from at least two hybrid rovings, whereby the fiber composite material is easier to produce and its mechanical properties are more homogeneous than in comparison to the prior art.

[0006] The problem is solved with a fiber composite material according to claim 1.

[0007] In the fiber composite material according to the invention, the fiber composite material has at least one tape, wherein the tape is constructed from at least two hybrid rovings. Each of the hybrid rovings consists of at least one layer of reinforcing fibers arranged directly between at least two layers of thermoplastic fibers. The layer of reinforcing fibers and the layers of thermoplastic fibers of each hybrid roving have a width transverse to the main propagation direction of the reinforcing fibers of more than 15 mm. At least two hybrid rovings are arranged next to one another transverse to the main propagation direction of the reinforcing fibers, without overlap, and thus form the at least one tape. The at least one tape has a width transverse to the main propagation direction of the reinforcing fibers of at least 30 mm. At least the reinforcing fibers are present within the fiber composite material without twisting.

[0008] A hybrid roving is understood to be a structure of at least three layers of fiber layers, wherein the different fiber layers within the hybrid roving are arranged on top of one another essentially perpendicular to the main propagation direction of the fibers (reinforcing fibers).

[0009] At least two hybrid rovings are used to form a tape. The hybrid rovings are arranged in the tape such that the fiber layers of the same type and the same layer of the different hybrid rovings lie next to each other, adjacent to one another (Figure 4). This means, for example, that the first layer of thermoplastic fibers of the first hybrid roving lie next to each other, without overlap, adjacent to the first layer of thermoplastic fibers of the second hybrid roving in the tape. The reinforcing fibers of the first hybrid roving, located between the first and second layers of thermoplastic fibers, are also arranged next to each other, without overlap, adjacent to the layer of reinforcing fibers of the second hybrid roving. Accordingly, the second layers of thermoplastic fibers of the first and second hybrid rovings lie next to each other, without overlap.This creates a tape that has a width transverse to the main propagation direction of the reinforcing fibers of at least 30 mm, but in which the fiber distribution is very uniform. The absence of overlapping areas of the same fiber types advantageously avoids localized areas with a higher fiber concentration, which can influence the mechanical properties of the subsequent fiber composite material. Furthermore, the use of tapes for producing the fiber composite material with a width transverse to the main propagation direction of the reinforcing fibers of at least 30 mm enables the fiber composite material to be manufactured from as few spools (of tape material) as possible, thereby reducing setup time. For example, only 10 spools need to be loaded with tape material to produce the fiber composite material instead of 20 or more spools, even though the subsequent fiber composite material is to have the same dimensions.

[0010] The fiber composite material can be formed from a plurality of tapes, wherein each tape can be formed from a plurality of hybrid rovings.

[0011] In one embodiment, the at least one tape is formed from two spread glass fiber rovings (reinforcing fibers) and four spread thermoplastic fiber rovings (which together form two hybrid rovings), with each of the fiber layers having a width of approximately 15 mm, measured transversely to the main propagation direction of the reinforcing fibers. In the tape, the layer of reinforcing fibers and the layers of thermoplastic fibers then have a width of 30 mm, measured transversely to the main propagation direction of the reinforcing fibers.

[0012] During the production of the fiber composite material, a pre-produced tape is preferably unwound from rolls or spools and processed into the fiber composite material. In another embodiment, however, the tape can also be formed during the production of the fiber composite material in a preliminary step by joining hybrid rovings. For example, a plurality of hybrid rovings can be spread apart in a first process step and placed accordingly to form a tape, with the at least one tape then being joined together to form the fiber composite material in a pultrusion process.

[0013] All three layers of each tape are subjected to a pressure of at least 2 bar and heat, preferably during the production of the fiber composite or prior to the production of the fiber composite (e.g., during the production of the tape), so that the thermoplastic fibers melt into a thermoplastic material that encloses the reinforcing fibers. The layer of encased reinforcing fibers is then cooled, preferably under pressure, until the thermoplastic material is no longer flowable. This advantageously makes it possible to produce the tape without overlapping areas and still obtain a manageable (layer-shift-resistant) tape.

[0014] In one embodiment, all three layers of each hybrid roving are subjected to a pressure of at least 2 bar and heat, preferably during the production of the fiber composite or prior to the production of the fiber composite (e.g., during the production of the tape), so that the thermoplastic fibers melt into a thermoplastic material that encloses the reinforcing fibers. Subsequently, the layer of enclosed reinforcing fibers is cooled, preferably under pressure, until the thermoplastic material is no longer flowable.

[0015] In the following, the layers of reinforcing fibers or thermoplastic fibers are also referred to as fiber layers. Furthermore, the at least one tape may also be referred to as tapes.

[0016] A fiber is a continuous or fixed-length structure whose width is negligibly small compared to its length. Both continuous fibers and staple fibers or hollow fibers are considered fibers. The fibers can be multifilament fibers or monofilament fibers. The fibers can also be core-sheath fibers. Furthermore, the fibers can be in the form of a yarn (e.g., multifilament yarn or ribbon yarn).

[0017] A width of the fiber layers in the hybrid roving transverse to the main propagation direction (also called fiber orientation) of the reinforcing fibers means that the width is measured in a plane of the reinforcing fiber layer but at an angle of approximately 90° to the main extension of the fiber. Accordingly, a width of the tape transverse to the main propagation direction (also called fiber orientation) means that the width is measured in a plane of the reinforcing fiber layer but at an angle of approximately 90° to the main extension of the fiber. According to the invention, the at least one tape, constructed from at least two hybrid rovings adjacent to one another without overlap, has a width that was previously unknown for such tapes.This allows the fiber composite material to be produced from a smaller number of hybrid rovings, and according to the invention, at least the reinforcing fibers within the fiber composite material are twist-free. This advantageously allows a uniform fiber orientation of the reinforcing fibers within the fiber composite material to be achieved, resulting in homogeneous, high mechanical properties of the fiber composite material. For example, a fiber composite material can be produced by unwinding and joining (for example, under pressure and heat) a plurality of hybrid rovings. With a large number of hybrid rovings, the hybrid rovings are twisted relative to one another during joining, as previously known from the prior art.The more hybrid rovings required to produce the fiber composite material, the greater the number of hybrid rovings exhibiting a twist. In producing the fiber composite material according to the invention, a smaller number of hybrid rovings can advantageously be used than previously. Combining at least two hybrid rovings into at least one tape also advantageously prevents twisting of the reinforcing fibers during production of the fiber composite material. Furthermore, the process for producing a fiber composite material is significantly simplified by using fewer, wide tapes, as, for example, the assembly time and setup time in the production process can be shortened.If the fiber composite material is produced, for example, by unwinding and joining tape rolls, fewer rolls need to be loaded at the beginning of the manufacturing process and possibly replaced later on. Advantageously, this makes the fiber composite material faster and requires fewer or no interruptions during production. A hybrid roving is a material formed from at least two different starting materials, with each of the starting materials being used as roving in the hybrid roving. A roving is a bundle, strand, or multifilament yarn made up of parallel filaments. One fiber layer of the hybrid roving is formed from one fiber roving.

[0018] A tape comprises at least two hybrid rovings. Each hybrid roving comprises spread fiber rovings that form the layers of thermoplastic fibers and the layer of reinforcing fibers. The hybrid roving can also comprise a plurality of thermoplastic fiber layers and layers of reinforcing fibers, which are then arranged one above the other in the hybrid roving (Figure 2). In a tape, the at least one fiber layer of reinforcing fibers can be formed from a plurality of rovings of reinforcing fibers that lie next to one another (and also one above the other). Likewise, each fiber layer of thermoplastic fibers can be formed from a plurality of rovings of thermoplastic fibers. The number of rovings used in the fiber layer of reinforcing fibers can be the same as or different from the number of rovings for the fiber layer of thermoplastic fibers, depending on how the tape is to be constructed.

[0019] Preferably, all hybrid rovings used to construct the tape are constructed in the same way and therefore have the same number of thermoplastic fiber layers and fiber layers made of reinforcing fibers.

[0020] In one embodiment, the at least one tape has a width measured transversely to the main propagation direction of the reinforcing fibers that is greater than its thickness, measured in the direction from the first fiber layer made of thermoplastic fibers to the second fiber layer made of thermoplastic fibers. Preferably, the width of the tape perpendicular to the fiber orientation is 20 to 25 times greater than the thickness of the tape, measured in the direction from the first fiber layer made of thermoplastic fibers to the second fiber layer made of thermoplastic fibers. Preferably, each hybrid roving also has a width measured transversely to the main propagation direction of the reinforcing fibers that is greater (preferably 20 to 25 times) than its thickness, measured in the direction from the first fiber layer made of thermoplastic fibers to the second fiber layer made of thermoplastic fibers.

[0021] In one embodiment, during the production of the fiber composite material, the thermoplastic fibers in the hybrid rovings—or in at least one tape—melt, and the reinforcing fibers are preferably completely surrounded by the thermoplastic material of the thermoplastic fibers, preferably without an edge region consisting solely of thermoplastic material. Regarding the structure and production of the hybrid roving, reference is made to the disclosure of the ribbon-shaped composite material in EP 3638492, the content of which is incorporated herein by reference.

[0022] In hybrid roving, the fiber layer of reinforcing fibers is preferably in direct contact with the two fiber layers of thermoplastic fibers. In at least one tape, the fiber layer of reinforcing fibers is also preferably in direct contact with the two fiber layers of thermoplastic fibers. The direct arrangement of the at least one layer of reinforcing fibers between the two layers of thermoplastic fibers means that no further layer of a different material is located between the reinforcing fibers and the layers of thermoplastic fibers.

[0023] The thermoplastic fibers in the hybrid rovings, or in at least one tape, can be present as filaments, staple fibers, multifilament fibers, yarn, monofilaments, or ribbon yarn made of thermoplastic material. Any material whose melting range or melting point does not exceed 500 °C, preferably not exceeding 350 °C, is suitable as the thermoplastic material for the thermoplastic fibers.

[0024] Preferably, thermoplastic fibers made of aliphatic and semi-aromatic polyamides, polyoxymethylene (POM), polyesters, PEEK, PEN, POK, PP, PE, or PVC, or mixtures thereof, are used. The thermoplastic fibers may contain thixotropic additives.

[0025] Preferably, pyrogenic silica, Luvotix HAT, Luvotix AB, Luvotix EAB, Luvotix P 100-15, BYK-405, BYK-420 or BYK-425 are used as thixotropic additives.

[0026] In one embodiment of the hybrid roving (or the at least one tape), the reinforcing fibers used for the fiber layer of reinforcing fibers are glass fiber (roving), carbon fiber (tow), basalt fiber, ceramic fiber, viscose fiber, metal fiber, aramid fiber, or natural fiber, or mixtures of the aforementioned fibers. Preferably, the at least one fiber layer of reinforcing fibers consists of approximately 60 to 100%, more preferably 80 to 95%, of one of the aforementioned fibers or a mixture of the aforementioned fibers.

[0027] Particularly preferred reinforcing fibers are glass fibers, with the glass fibers preferably having a fineness of 1200 to 2400 tex.

[0028] Preferably, a fiber layer of thermoplastic fibers consists of at least one layer, preferably two layers, of thermoplastic multifilament yarns arranged unidirectionally and one above the other in the hybrid roving. Preferably, the at least one tape also comprises two layers of thermoplastic multifilament yarns arranged unidirectionally and one above the other.

[0029] Preferably, the at least one fiber layer of reinforcing fibers in the hybrid roving consists of a layer of unidirectionally arranged reinforcing fibers. Preferably, the reinforcing fibers within the fiber layer of reinforcing fibers in the hybrid roving lie adjacent to and against one another without overlapping.

[0030] Preferably, the width of the at least one fiber layer made of reinforcing fibers and the at least two fiber layers made of thermoplastic fibers in the hybrid roving transversely to the main propagation direction of the reinforcing fibers is more than 30 mm, more than 50 mm, more than 100 mm, more than 250 mm, more than 500 mm or more than 600 mm.

[0031] In one embodiment, the at least one tape comprises at least one fiber layer made of reinforcing fibers and at least two fiber layers made of thermoplastic fibers. Preferably, the width of the at least one fiber layer made of reinforcing fibers and the at least two fiber layers made of thermoplastic fibers in the at least one tape, transverse to the main propagation direction of the reinforcing fibers, is more than 30 mm, more than 50 mm, more than 100 mm, more than 250 mm, more than 500 mm, or more than 600 mm.

[0032] In one embodiment, the fiber composite material is formed from hybrid rovings with a plurality of fiber layers of reinforcing fibers, wherein the reinforcing fibers are arranged in the hybrid roving at least in partial regions perpendicular to the main propagation direction of the reinforcing fibers, either offset or without offset, one above the other. In one embodiment, the fiber composite material is formed from at least two tapes, wherein the tapes are arranged in the fiber composite material at least in partial regions perpendicular to the main propagation direction of the reinforcing fibers, either offset or without offset, one above the other.

[0033] In one embodiment, the basis weight within the fiber layer of reinforcing fibers and / or within the fiber layers of thermoplastic fibers in each of the at least two hybrid rovings and / or in the at least one tape is constant. Constant means that the basis weight within the fiber layer varies by less than 5%.

[0034] Preferably, each of the at least two hybrid rovings and / or the at least one tape comprises a temporary binder. Examples of suitable temporary binders include thermoplastic dispersions, such as polypropylene in water, wherein the proportion of binder to the fiber content of the hybrid rovings and / or the at least one tape is in the range from 0.3 to 10 wt.%, preferably 3 wt.%, based on the total fiber content of the hybrid roving or the at least one tape. The binder is a temporary binder if it is removed from the hybrid roving and / or the at least one tape during or before production of the fiber composite material, or is later dissolved in a matrix material of the fiber composite material. For example, the binder can be evaporated using heat before the hybrid rovings are joined to form the at least one tape.In another embodiment, the binder is only evaporated by heat during the production of the fiber composite material. The temporary binder can advantageously strengthen the temporary bonding of the various fiber layers within each hybrid roving, making the hybrid rovings easier to handle. Furthermore, the temporary binder also strengthens the temporary bonding of the various fiber layers of the different hybrid rovings in the at least one tape. This makes it even easier to form the at least one tape without overlapping fiber layers of different hybrid rovings.

[0035] In one embodiment, the temporary binder acts as an adhesion promoter in the subsequent fiber composite material. Preferably, the binder in the hybrid roving binds the various fiber layers together, thereby improving the handleability of the hybrid roving and then ensures better adhesion in the fiber composite material between the material of the hybrid rovings and the additional matrix material that is used in addition to the hybrid rovings to produce the fiber composite material. Preferably, the binder in at least one tape binds the various fiber layers together, thereby improving the handleability of the at least one tape and then ensures better adhesion in the fiber composite material between the material of the at least one tape and the additional matrix material that is used in addition to the fiber composite material to produce the fiber composite material.

[0036] The temporary binder is preferably a pressure-sensitive adhesive. In the present application, a pressure-sensitive adhesive is understood to mean materials that exhibit high initial adhesion (also known to those skilled in the art as "tack"), i.e., that form adhesive bonds with objects that come into contact with the material in question within a very short time. Possible pressure-sensitive adhesives are polymers or copolymers based on acrylates, specifically those based on 2-ethylhexyl acrylate, isoamyl acrylate, hydroxymethacrylate, isooctyl acrylate, acrylic acid, methyl methacrylate, or butyl acrylate. The polymers or copolymers used as pressure-sensitive adhesives may also contain styrene, natural rubber, polyterpene resin, polyisoprene, styrene-butadiene rubber, styrene-butadiene rubber, isobutene-isoprene rubber, acrylonitrile-butadiene rubber, chloroprene rubber, polyvinyl acetate, or polydiphenyldisiloxane. In one embodiment, the pressure-sensitive adhesive contains swellable acrylate beads.In one embodiment, the pressure-sensitive adhesive contains a solvent or swelling agent, such as water, an alcohol such as ethanol, methanol, 1-propanol, or 2-propanol, a ketone such as acetone or methyl ethyl ketone, or an alkane such as n-hexane, n-heptane, or petroleum ether. In one embodiment, the component added as a pressure-sensitive adhesive retains its adhesive strength even after heat treatment of the hybrid roving at, for example, 180°C. In one embodiment, the pressure-sensitive adhesive is designed such that it loses its tacky properties over time, for example, due to exposure to light, atmospheric oxygen, or the evaporation of a solvent or swelling agent.

[0037] In one embodiment, the quantity and type of pressure-sensitive adhesive are selected such that the resulting bond can be released by applying a force of approximately 0.01 mN / tex. In this context, approximately means a deviation of 50% upwards or downwards.

[0038] A further subject matter of the present invention relates to the fiber composite material. Statements regarding the hybrid rovings and the at least one tape apply (where appropriate) to the fiber composite material to be produced from at least two hybrid rovings—in at least one tape. Within the at least one tape, the layers of reinforcing fibers from different hybrid rovings are adjacent to one another without bonding or overlapping, transverse to the main propagation direction of the reinforcing fibers. Preferably, the layers of thermoplastic fibers from different hybrid rovings are also adjacent to one another without bonding or overlapping, transverse to the main propagation direction of the reinforcing fibers, within the at least one tape.

[0039] Preferably, the fiber composite material is formed from fewer than 400, preferably fewer than 300, preferably fewer than 250, preferably fewer than 100, preferably fewer than or equal to 10 hybrid rovings. Preferably, the fiber composite material is formed from fewer than 400, preferably fewer than 300, preferably fewer than 200, preferably fewer than 250, preferably fewer than 150, preferably fewer than 125, preferably fewer than 100, preferably fewer than 50, preferably fewer than or equal to 10, or fewer than or equal to 5 tapes. Preferably, each of these tapes comprises three or more hybrid rovings.

[0040] Preferably, the fiber composite material is made exclusively from one type of hybrid roving, so that all hybrid rovings have the same structure and contain the same material.

[0041] Preferably, the fiber composite material is made exclusively from one type of tape, so that all tapes have the same structure and contain the same material.

[0042] The fiber composite material preferably has a homogeneous fiber distribution in the thickness and / or width direction. A homogeneous fiber distribution means that the fiber distribution of the reinforcing fibers within the fiber composite material varies by less than 5%. This advantageously results in a fiber composite material that has no reinforcing fiber-free regions consisting solely of matrix material. This advantageously makes the mechanical properties of the fiber composite material particularly predictable.

[0043] In one embodiment, the fiber composite material is a pultrudate. A pultrudate is understood to be a fiber composite material formed from at least one tape in a pultrusion process, wherein the at least one tape is formed from at least two hybrid rovings. In one embodiment, the hybrid rovings are guided via fiber guides from a multi-level spool store, spread apart, and joined together to form at least one tape, wherein the fiber layers of the hybrid rovings are adjacent to one another in the tape, without overlap, transverse to the main propagation direction of the reinforcing fibers. The at least one tape is fed into a hot pultrusion tool. In this tool, the thermoplastic fibers melt and form a matrix. The additional addition of matrix material to produce the pultrudate is not necessary when using hybrid rovings.The fibers can pass through several preforming stations so that they are brought to the desired pultrudate shape.

[0044] Preferably, the pultrudate has a rod shape, wherein the rod shape is solid and has a diameter of at least 2 mm.

[0045] In one embodiment, the surface of the pultrudate can have a structure with a predetermined thickness. For example, the pultrudate can have a surface similar to that of steel reinforcement bars in concrete construction.

[0046] Preferably, the pultrudate has a flat profile shape (rectangular), the shape being solid and having a thickness of at least 0.2 mm and a width of at least 6 mm.

[0047] The present invention further relates to a method for producing the fiber composite material as described above. In this respect, the above statements also apply to the manufacturing process.

[0048] In the manufacturing process, 10, no more than 10, or more than 10 hybrid rovings^) are unwound and assembled into at least one tape, wherein the at least one tape is processed into the fiber composite material. Each of the hybrid rovings has a width of at least 15 mm transverse to the fiber orientation of the hybrid roving, and at least the reinforcing fibers are joined together to form the fiber composite material without twisting. Within the at least one tape, the hybrid rovings lie next to one another without overlap, transverse to the main propagation direction of the reinforcing fibers.

[0049] In the manufacturing process, 10, no more than 10, or more than 10 tapes can be unwound and processed into the fiber composite material. In the manufacturing process, 5, no more than 5, or more than 5 tapes can be unwound and processed into the fiber composite material, with each tape being formed from at least two hybrid rovings.

[0050] Preferably, in the manufacturing process of the fiber composite material, no more than 300 hybrid rovings are used for production, wherein each hybrid roving has a width transverse to the fiber orientation of more than 15 mm and / or the fiber composite material has a width transverse to the fiber orientation of more than 30 mm, preferably more than 50 mm.

[0051] By using at least one tape, in which at least two hybrid rovings are joined together, the risk of fiber twisting during the production of the fiber composite is significantly reduced. This increases the uniformity of the fiber composite. Furthermore, friction and pressure fluctuations in the consolidation tool are reduced, since only relatively few tapes need to be used for production. As already described above, this can advantageously improve the mechanical properties of the fiber composite.

[0052] In one embodiment, the hybrid rovings are first combined into a tape in a separate process step. The rolls of tape are then wound up and can be stored. To produce the fiber composite, the rolls (or spools) of tape are then unwound and processed into the fiber composite. However, the at least one tape can also be produced as a temporary intermediate product after the hybrid rovings are unwound and before the fiber composite is produced, without the at least one tape being wound up (stored and later processed).

[0053] Preferably, the hybrid rovings are joined to form at least one tape in such a way that the thermoplastic fibers of the hybrid rovings are also twist-free. However, at the latest during the manufacturing process of the fiber composite material, the thermoplastic fibers are completely melted, so that the fiber orientation of the thermoplastic fibers can no longer be determined in the fiber composite material. The thermoplastic fiber material encloses the reinforcing fibers and forms the matrix of the fiber composite material, or bonds with an added matrix material.

[0054] In one embodiment, the fiber composite material is made from a plurality of tapes, whereby all tapes have the same structure (same material, same number of fibers, same number of layers)

[0055] In another embodiment, the fiber composite material is produced from a plurality of tapes, wherein at least two types of tapes are used. The at least two types of tapes differ from one another in the type of material used for the fibers, the number of fibers within the various layers, the fiber spreading within a layer, and / or the number of fiber layers within the tape. The present invention further provides a tape for producing a fiber composite material as described above, wherein the tape has a width transverse to the main orientation of the reinforcing fibers of at least 30 mm.The tape is formed from at least two hybrid rovings, each with a width of at least 15 mm perpendicular to the main propagation direction of the reinforcing fibers, and whose reinforcing fibers are bonded to one another within the tape and adjacent to one another without overlapping perpendicular to the main propagation direction of the reinforcing fibers. All the above statements regarding the fiber composite material and its manufacturing process apply equally to the tape. Likewise, all subsequent explanations regarding the tape apply to both the manufacturing process of the fiber composite material and the fiber composite material itself.

[0056] The tape has (at least) one fiber layer made of reinforcing fibers, which is formed from the fiber layers made of reinforcing fibers of at least two hybrid rovings, wherein the fiber layers made of reinforcing fibers of different hybrid rovings are arranged adjacent to one another within the tape without overlapping (within the layer of reinforcing fibers of the tape). Furthermore, the fiber layers made of thermoplastic fiber material of the tape are each formed from a plurality of fiber layers made of thermoplastic fibers of different hybrid rovings. Each layer of thermoplastic fiber material in the tape has at least two layers made of thermoplastic fiber material of different hybrid rovings, which are arranged adjacent to one another within the thermoplastic fiber layer of the tape without overlapping.The tape can also be formed from more than two hybrid rovings, in which case this tape is constructed similarly to the tape just described (only with more fiber layers adjacent to one another without overlap). The at least one tape can, for example, be formed from at least 3, at least 5, or at least 10 hybrid rovings, with each layer of reinforcing fibers of the hybrid rovings having a width transverse to the main propagation direction of the reinforcing fibers of at least 15 mm, and the reinforcing fibers of different hybrid rovings within the tape being adjacent to one another without overlap, transverse to the main propagation direction of the reinforcing fibers (thus forming the layer of reinforcing fibers of the tape).

[0057] Within a tape, each hybrid roving may also have a first fiber layer of thermoplastic fibers formed from a different number of fibers and / or a different fiber material type than a second fiber layer of thermoplastic fibers of the same hybrid roving.

[0058] The invention is described in more detail below with reference to figures, wherein the figures merely represent embodiments of the invention and are therefore not restrictive.

[0059] Figure 1 shows schematically a possible manufacturing method of a hybrid roving

[0060] Figure 2 shows schematically an embodiment of a hybrid roving

[0061] Figure 3 shows a schematic diagram of the structure of a tape.

[0062] Figure 4 shows schematically the arrangement of a plurality of tapes for producing the composite material. Figure 5 shows schematically the structure with two tapes which are used for

[0063] Fiber composite material can be processed

[0064] Figure 1 schematically illustrates one possible way of producing a hybrid roving. According to this example, a hybrid roving is produced from three rolls of material as starting material. The outer material webs are spread thermoplastic fibers, with a web of spread reinforcing fibers (e.g., glass fibers) being fed into the center. The reinforcing fibers are then positioned between the webs of thermoplastic fibers, so that the thermoplastic fibers cover a top and bottom side of the reinforcing fibers. In one embodiment, an adhesive and / or a binder can be applied to one or more of the fiber layers before all the fiber layers are combined to form the hybrid roving.In another embodiment for producing the hybrid roving, all layers of thermoplastic fibers and all layers of reinforcing fibers are first combined to form a hybrid roving, and then an adhesive and / or a binder is applied to the hybrid roving. The adhesive and / or binder is preferably applied via a roller application, with one or more fiber webs or the hybrid roving being guided over a roller (roller) provided with the appropriate adhesive and / or binder. The fiber layers are layered on top of one another and then joined together, preferably under pressure, and dried. This fixes the fiber layers to one another, so that the individual fiber layers cannot subsequently be separated from one another without corresponding force.Preferably, the fixation of the various fiber layers within the hybrid roving is so strong that the hybrid roving can be easily wound and later unwound after fixation without the various fiber layers separating. Furthermore, the fixation is so strong that even during the production of the fiber composite material from the hybrid roving (in the form of at least one tape), the fiber layer structure is retained.

[0065] Figure 2 schematically shows an embodiment of a hybrid roving. In the example of Figure 2, the hybrid roving consists of a spread glass fiber roving arranged between two spread rovings made of thermoplastic fibers. Preferably, the glass fiber roving is spread such that it has a thickness (measured in the direction from one fiber layer made of thermoplastic fibers to the other fiber layer made of thermoplastic fibers) that is greater than the individual thicknesses of the fiber layers made of thermoplastic fibers. In this case, the hybrid roving has three fiber layers, two of which are made of the same material (thermoplastic fibers) and one of which is made of reinforcing fibers.The hybrid roving preferably has a width transverse to the main propagation direction of the reinforcing fibers of more than 15 mm and, at the same time, a thickness (measured in the direction from one fiber layer of thermoplastic fibers to the other fiber layer of thermoplastic fibers) of between 0.2 and 0.4 mm. Consequently, the hybrid roving preferably has a width that is significantly greater than its thickness. Preferably, the hybrid roving has a width that is 20 to 25 times greater than its thickness.

[0066] Figure 3 shows a schematic representation of a tape 1. In the embodiment of Figure 3, the tape 1 is formed from two hybrid rovings 2, 2', wherein the hybrid rovings 2, 2' lie adjacent to one another without overlapping within the tape 1. Preferably, within the tape 1, the first layer of thermoplastic fibers of the first and second hybrid rovings lie adjacent to one another without overlapping, the layers of reinforcing fibers 3 of the first hybrid roving and the second hybrid roving lie adjacent to one another without overlapping within the tape, and the second layers of thermoplastic fiber material of the first and second hybrid rovings lie adjacent to one another without overlapping. In Figure 3, the layer of reinforcing fibers 3 of one of the hybrid rovings 2 has only been sketched out.

[0067] Figure 4 again schematically shows the structure of the tape consisting of at least two hybrid rovings 2, 2'. A first hybrid roving 2 has the same structure as a second hybrid roving 2'. The hybrid rovings 2, 2' are laid together to form the tape 1. As can also be seen in the figure, identical fiber layers of the different hybrid rovings lie next to one another without overlapping, adjacent to one another within the tape 1. The different hybrid rovings 2, 2' can, for example, have a binder or a pressure-sensitive adhesive that enables the different fiber layers of each hybrid roving 2, 2' to hold together even without overlapping of the fiber layers. Additionally or alternatively, the fiber layers of the hybrid rovings 2, 2' can also be bonded by pressure and heat to form a tape 1 without overlapping areas.

[0068] Figure 5 shows a structure with two tapes 1 that can be processed into a fiber composite material. Each tape 1 has two hybrid rovings 2, 2' or 2", 2'". The tapes 1 can be arranged one above the other with an offset to one another, as in the example in Figure 4, whereby within a horizontal layer of tapes 1, these tapes lie without offset to one another. Preferably, the tapes 1 lie next to one another in a horizontal layer without overlap. The tapes 1 of different (horizontal) layers can be constructed the same or differently to one another. Preferably, the tapes 1 of a horizontal layer are constructed the same to one another. A layer of reinforcing fibers 3 of a hybrid roving 2' has been shown schematically.

Claims

Claims:

1. Fiber-reinforced composite material comprising at least two hybrid rovings (2, 2'), wherein each of the at least two hybrid rovings (2, 2') is composed of at least one layer of reinforcing fibers (3) and at least two layers of thermoplastic fibers, wherein the at least one layer of reinforcing fibers (3) is arranged between the at least two layers of thermoplastic fibers in the hybrid roving (2, 2') and at least the reinforcing fibers are arranged within the fiber-reinforced composite material without twisting, wherein the layer of reinforcing fibers (3) and the layers of thermoplastic fibers of each hybrid roving (2, 2') have a width transverse to the main propagation direction of the reinforcing fibers which is more than 15 mm, characterized in that the at least two hybrid rovings (2, 2') are arranged side by side without overlap transverse to the main propagation direction of the reinforcing fibers,are provided adjacent to one another in at least one tape (1) within the fiber composite material, wherein the at least one tape (1) has a width transverse to the main propagation direction of the reinforcing fibers of at least 30 mm.

2. Fiber composite material according to claim 1, wherein the width of the at least one tape (1) transverse to the main propagation direction of the reinforcing fibers is more than 50 mm, more than 100 mm, more than 250 mm, more than 500 mm or more than 600 mm. Fiber-reinforced composite material according to at least one of the preceding claims, wherein within the fiber layer of reinforcing fibers (3) in the hybrid roving and / or in the tape (1), the reinforcing fibers are arranged side by side and adjacent to one another without overlap. Fiber-reinforced composite material according to at least one of the preceding claims, wherein, in the case of a plurality of fiber layers of reinforcing fibers (3) within a hybrid roving (2, 2'), the different fiber layers of reinforcing fibers (3) are arranged, at least in partial regions, perpendicular to the main propagation direction of the reinforcing fibers, either without offset or with an offset, one above the other in the hybrid roving (2, 2').Fiber-reinforced composite material according to at least one of the preceding claims, wherein the fiber-reinforced composite material comprises at least two tapes (1) arranged within the fiber-reinforced composite material perpendicular to the main propagation direction of the reinforcing fibers, either without offset or with an offset. Fiber-reinforced composite material according to at least one of the preceding claims, wherein the basis weight is constant in each hybrid roving (2, 2') and / or in the at least one tape (1) within the fiber layer of reinforcing fibers (3) and / or wherein the basis weight is constant within the layers of thermoplastic fibers. Fiber-reinforced composite material according to at least one of the preceding claims, wherein the at least two hybrid rovings comprise a temporary binder.

8. Fiber composite material according to at least one of the preceding claims, wherein the fiber composite material has more than 10 hybrid rovings (2,2'), but preferably less than 100 hybrid rovings (2,2').

9. Fiber composite material according to at least one of the preceding claims, wherein the fiber composite material has a homogeneous fiber distribution in the thickness and / or width direction.

10. Fiber composite material according to at least one of the preceding claims, wherein the fiber composite material is a pultrudate.

11. Fiber composite material according to claim 10, wherein the pultrudate has a rod shape and a diameter of at least 2 mm.

12. Fiber composite material according to at least one of the preceding claims, wherein the layers of reinforcing fibers (3) of different hybrid rovings (2, 2') within the at least one tape (1 ) are arranged side by side without adhesive bonding and without overlapping in the direction of propagation of the reinforcing fibers.

13. Method for producing the fiber composite material according to claim 1, wherein at least two, preferably more than 10, hybrid rovings (2, 2') are unwound and joined together to form a fiber composite material, wherein each hybrid roving (2, 2') has a width of at least 15 mm transverse to the main propagation direction of the reinforcing fibers, wherein the hybrid rovings (2, 2') are laid side by side without overlapping, abutting each other, transverse to the main propagation direction of the reinforcing fibers, forming at least one tape (1) which has a width of at least 30 mm transverse to the main propagation direction of the reinforcing fibers and at least the reinforcing fibers are twist-free to Fiber composite material is assembled. Method for producing the fiber composite material according to claim 13, wherein no more than 400 hybrid rovings (2, 2') are used for production, wherein the fiber composite material has a width transverse to the main propagation direction of the reinforcing fibers of more than 30 mm. Tape (1) for producing a fiber composite material according to claim 1, wherein the tape (1) is formed from at least two hybrid rovings (2, 2') having a width transverse to the main propagation direction of the reinforcing fibers of at least 15 mm, and whose reinforcing fibers are adjacent to one another without overlap within the tape (1) transverse to the main propagation direction of the reinforcing fibers.Tape (1 ) according to claim 15, wherein the tape (1 ) is formed from at least 3, at least 5 or at least 10 hybrid rovings (2,2'), wherein each layer of reinforcing fibers (3) of the hybrid rovings (2,2') has a width transverse to the main propagation direction of the reinforcing fibers of at least 15 mm and the reinforcing fibers of different hybrid rovings (2,2') within the tape (1 ) are adjacent to each other without adhesion and without overlapping transverse to the main propagation direction of the reinforcing fibers.

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