Fabric and fabric prepreg

Abstract

To provide an intermediate base material for molding a fiber-reinforced plastic, which is excellent in mechanical characteristics while having shape followability.SOLUTION: There are provided: a woven fabric composed of a fiber bundle of continuous carbon fibers, wherein the average fiber bundle meandering rate in at least one fiber bundle direction is 1.05 or more and 2.0 or less; and a woven fabric prepreg obtained by impregnating the woven fabric with a resin.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a woven fabric used mainly for intermediate substrates (prepregs) of fiber-reinforced plastics. [Background technology]

[0002] Demand for fiber-reinforced plastics is increasing year by year due to their excellent mechanical properties, such as high specific strength and specific modulus of elasticity, as well as their high performance properties, such as weather resistance and chemical resistance.

[0003] Prepreg, which is made by impregnating continuous reinforcing fibers with a matrix resin, is widely used as an intermediate substrate for fiber-reinforced plastics. Prepreg has high mechanical properties because it is possible to increase the reinforcing fiber content by orienting the reinforcing fibers in one direction. However, because the reinforcing fibers are continuous, it has the problem of poor conformability to complex shapes such as three-dimensional shapes.

[0004] To address this issue, a cut prepreg has been disclosed, in which cuts are inserted into a prepreg with reinforcing fibers oriented in one direction, as an intermediate substrate that combines mechanical properties and shape conformability (for example, Patent Document 1). Although this cut prepreg is composed of discontinuous fibers, it has the high fiber volume content and reinforcing fiber orientation that are unique to prepreg, and therefore has high mechanical properties while also being able to be molded into complex shapes that are not possible with conventional continuous fiber prepregs.

[0005] Furthermore, a preform using a reinforcing fiber fabric has been disclosed as an intermediate substrate that combines mechanical properties and shape conformability (for example, Patent Document 2). A fabric made of reinforcing fibers has shape conformability due to shear deformation of the weave, and is therefore used to mold three-dimensional shapes. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-146151 [Patent Document 2] Japanese Patent Application Publication No. 2018-145539 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the incised prepreg described in Patent Document 1 has incisions that separate the reinforcing fibers, which means that it has inferior mechanical properties compared to continuous fiber prepregs. Furthermore, because the reinforcing fibers are cut, the incisions can open wide depending on the molding shape, causing the incised prepreg itself to break. In the preform described in Patent Document 2, the deformation of the preform is limited by the weave structure, so the shapes that can be molded are limited.

[0008] An object of the present invention is to provide an intermediate substrate for molding fiber-reinforced plastics that has shape conformability and excellent mechanical properties. [Means for solving the problem]

[0009] The above-mentioned problems can be solved by a woven fabric composed of fiber bundles made of continuous carbon fibers, in which the average meandering ratio of the fiber bundles in at least one fiber bundle direction is 1.05 or more and 2.0 or less, and a woven fabric prepreg made from such a woven fabric. [Effects of the Invention]

[0010] According to the present invention, an intermediate substrate for molding carbon fiber reinforced plastics can be obtained that has shape conformability and excellent mechanical properties, thereby making it possible to easily mold molded articles having complex shapes. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram illustrating one embodiment of a woven fabric of the present invention. [Figure 2] Schematic diagram of the cut prepreg used in the examples. DETAILED DESCRIPTION OF THE INVENTION

[0012] [fabric] In the present invention, a woven fabric refers to a textile composed of fiber bundles of continuous fibers and having intersections between the fiber bundles. The fiber bundle refers to a collection of fibers in which continuous reinforcing fibers oriented in approximately the same direction are bundled. The weave of the woven fabric of the present invention is not particularly limited, but examples include plain weave, twill weave, and satin weave. Among these, plain weave is preferred because it has an excellent balance of shape conformability and mechanical properties.

[0013] The woven fabric of the present invention is a woven fabric made from fiber bundles of carbon fibers, i.e., a carbon fiber woven fabric. The use of carbon fibers has the effect of providing lightweight and excellent mechanical properties when used in fiber-reinforced plastics. Furthermore, because the carbon fibers themselves have a high elastic modulus and are rigid, entanglement of the carbon fibers within the fiber bundles is unlikely to occur, making it easy to form meandering fibers in the woven fabric, as described below. Furthermore, because the strength is high and breakage of the meandering fiber bundles during elongation is suppressed, fiber-reinforced plastics with excellent mechanical properties can be obtained.

[0014] The type of carbon fiber contained in the fiber bundle is not particularly limited, and may be PAN-based, pitch-based, or rayon-based carbon fiber. PAN-based carbon fiber is preferred because it is easy to form a meandering shape (described later) and has an excellent balance between strength and elastic modulus in terms of improving the mechanical properties of the fiber-reinforced plastic after molding. While a carbon fiber bundle is typically a fiber bundle consisting of only carbon fibers, in the present invention, it also includes a fiber bundle in which 90% or more of the reinforcing fibers, calculated as the number of fibers, are carbon fibers, as long as the effect is not lost. Examples of reinforcing fibers other than carbon fibers that may be contained in the fiber bundle include glass fibers, aramid fibers, alumina fibers, silicon carbide fibers, boron fibers, metal fibers, natural fibers, and mineral fibers.

[0015] The number of fibers constituting the fiber bundle is not particularly limited, but from the viewpoint of facilitating the formation of meandering as described below, the number of reinforcing fibers contained in the fiber bundle is preferably 12,000 or less, more preferably 6,000 or less, and most preferably 3,000 or less.

[0016] The woven fabric of the present invention has an average fiber bundle meandering ratio of 1.05 to 2.0 in at least one fiber bundle direction. By satisfying this condition, the meandering fiber bundles can be stretched in the fiber bundle direction, resulting in a woven fabric that has excellent shape conformability during fiber-reinforced plastic molding and mechanical properties when made into fiber-reinforced plastic.

[0017] The woven fabric of the present invention will be described in detail with reference to FIG. 1. FIG. 1 is a schematic diagram of the woven fabric of the present invention viewed from the out-of-plane direction. The woven fabric 1 of the present invention has a weave structure composed of a plurality of fiber bundles 2. The weave structure includes fiber bundle groups 4 composed of groups of fiber bundles in which the orientation direction 3 of each fiber bundle is substantially the same. Here, the fiber bundle orientation direction 3 is defined as the direction along a line segment extracted from the fiber bundle 2, connecting the ends 5 of the fiber bundles at the shortest distance, with the length of the line segment being 100 mm or longer. When the orientation direction 3 of an arbitrarily selected fiber bundle 2 is taken as a reference direction, a fiber bundle group 4 is identified as a collection of fiber bundles whose orientation direction 3 intersects or is parallel to the reference direction at an angle of 20° or less. The fiber bundle groups 4 identified in this manner are considered to have the same fiber bundle direction. Note that the woven fabric of the present invention may have multiple fiber bundle groups with different fiber bundle directions. FIG. 1 shows an example formed from two fiber bundle groups 4 with different fiber bundle directions.

[0018] The meandering ratio of a fiber bundle is a value defined as "the length of the extracted fiber bundle" divided by "the length of the line segment" when a portion of each fiber bundle 2 is extracted such that the length of the line segment connecting the ends 5 at the shortest distance is 100 mm or more. The larger the meandering ratio, the greater the meandering of the fiber bundle relative to the orientation direction of the fiber bundle. The average meandering ratio is calculated by averaging the meandering ratios of 10 fiber bundles 2 arbitrarily selected from one fiber bundle 2 belonging to one fiber bundle group 4. If the number of fiber bundles 2 belonging to one fiber bundle group 4 is less than 10, the average meandering ratio calculated for all fiber bundles may be used. If the average meandering ratio is less than 1.05, shape conformability may be insufficient, and a fiber-reinforced plastic with the desired shape may not be obtained. If the average meandering ratio exceeds 2.0, significant meandering of the fiber bundles may remain in the fiber-reinforced plastic, preventing the desired mechanical properties from being obtained and possibly adversely affecting surface quality. The average meandering ratio is more preferably in the range of 1.1 or more and 1.8 or less, and even more preferably in the range of 1.2 or more and 1.5 or less.

[0019] In the woven fabric of the present invention, the average meandering ratio of the fiber bundles in at least one fiber bundle direction may be within the above range, but in order to impart isotropic shape conformability, it is preferable that the average meandering ratios in all fiber bundle directions be within the above range.

[0020] In the woven fabric of the present invention, the coefficient of variation of the meandering ratio of the meandering fiber bundle is preferably 20% or less. When this condition is satisfied, the variation in the length of the fiber bundles contained in one fiber bundle group is suppressed, and the disorder of the weave structure during shape conformity can be suppressed. Here, the coefficient of variation of the meandering ratio is expressed as "standard deviation" / "average value" of the meandering ratios of 10 fiber bundles arbitrarily selected to calculate the average meandering ratio × 100 [%], and the smaller this value, the smaller the variation in the meandering ratio. The coefficient of variation of the meandering ratio is more preferably 10% or less, and even more preferably 5% or less.

[0021] In the woven fabric of the present invention, it is preferable that the meandering fiber bundles meander in the in-plane direction of the fabric. When this condition is satisfied, good shape conformability is exhibited during molding of the fiber-reinforced plastic. Furthermore, when this condition is satisfied, unevenness in the thickness direction of the woven fabric of the present invention is suppressed, resulting in a fiber-reinforced plastic with excellent surface quality. Whether the fiber bundles meander in the in-plane direction of the fabric is determined as follows. First, when the woven fabric is observed from the out-of-plane direction as shown in Figure 1, if the fiber bundle 2 and the line segment connecting the ends 5 of the fiber bundles 2 at the shortest distance (the line segment overlapping with the fiber bundle orientation direction 3) do not overlap and intersect at least one point other than the ends 5, the fiber bundle is determined to meander in the in-plane direction. Next, ten fiber bundles randomly selected from fiber bundles belonging to one fiber bundle group are determined to meander in the in-plane direction for each fiber bundle. If eight or more of the ten fiber bundles are determined to meander in the in-plane direction, the fiber bundles in that fiber bundle direction, i.e., one fiber bundle group, are determined to meander in the in-plane direction of the fabric.

[0022] In the woven fabric of the present invention, it is preferable that the meandering fiber bundles meander at a substantially constant pitch. When this condition is satisfied, the woven fabric exhibits uniform shape-following properties. Here, "fiber bundles meander at a substantially constant pitch" refers to a state in which, in one fiber bundle group, the fiber bundles have multiple bends, and the coefficient of variation, expressed as the standard deviation / average value x 100 [%] of the distance (pitch) in the fiber bundle orientation direction 3 between adjacent vertices 6 of the bends, is 20% or less. Whether or not the fiber bundles meander at a substantially constant pitch is determined for each fiber bundle group. The coefficient of variation of the pitch is calculated for each of 10 fiber bundles arbitrarily selected from the fiber bundles belonging to one fiber bundle group, and if the average value is 20% or less, the fiber bundles included in that fiber bundle group are determined to meander at a substantially constant pitch.

[0023] In the woven fabric of the present invention, it is preferable that the meandering fiber bundle meanders at a substantially constant width. Meeting this condition is preferable because good shape conformability is exhibited during molding of fiber-reinforced plastic. Here, "a fiber bundle meanders at a substantially constant width" refers to a state in which the fiber bundle has multiple bends, and the coefficient of variation, expressed as the standard deviation / average value x 100 [%] of the distance (width) between adjacent vertices 6 of the bends in a direction perpendicular to the orientation direction of the fiber bundle, is 20% or less. Whether or not the fiber bundle meanders at a substantially constant width is determined for each fiber bundle group. The coefficient of variation of the width is calculated for each of 10 fiber bundles arbitrarily selected from fiber bundles belonging to one fiber bundle group. If the average value is 20% or less, the fiber bundles included in that fiber bundle group are determined to meander at a substantially constant width.

[0024] The woven fabric of the present invention does not necessarily have to be composed of carbon fiber bundles alone, and may contain auxiliary threads, stitch threads, etc. as needed.

[0025] [Woven prepreg] The woven fabric of the present invention is preferably used as a material for a prepreg, which is an intermediate substrate in the production of fiber-reinforced plastics. Such a woven fabric prepreg obtained by impregnating the woven fabric of the present invention with a resin is one aspect of the present invention, and has excellent shape conformability during fiber-reinforced plastic molding and mechanical properties of the molded product. When the woven fabric is used alone, the force applied to the woven fabric may not be transmitted, resulting in disorder of the weave structure. However, by impregnating the woven fabric with a resin, the force is transmitted over a wide range via the resin, making it possible to maximize the shape conformability of the woven fabric and suppress disorder of the weave structure during molding.

[0026] In the woven fabric prepreg of the present invention, the type of resin is not particularly limited, and thermosetting resins, thermoplastic resins, and copolymers thereof can be used. A mixture of multiple resins may also be used. As a thermosetting resin, epoxy resin is particularly preferred from the viewpoint of the mechanical properties and heat resistance of the molded article. As a thermoplastic resin, polyolefin is preferred from the viewpoint of the light weight of the resulting molded article, polyamide is preferred from the viewpoint of strength, polyarylene sulfide is preferred from the viewpoint of heat resistance, polyether ether ketone is preferred from the viewpoint of continuous use temperature, and fluorine-based resin is preferred from the viewpoint of chemical resistance. In the present invention, if the main component of the matrix resin (a component exceeding 50% by weight when the entire matrix is ​​taken as 100% by weight), it is called a thermoplastic resin, and if it is a thermosetting resin, it is called a thermosetting resin. Among these, a thermosetting resin is most preferred from the viewpoint of shape conformability and mechanical properties.

[0027] [Preform] A preform including a woven fabric prepreg obtained by impregnating a woven fabric of the present invention with a resin, particularly a preform obtained by laminating the woven fabric prepreg of the present invention with a discontinuous fiber prepreg containing discontinuous reinforcing fibers and a resin, is preferred because it has an excellent balance of shape conformability and mechanical properties. Therefore, such a preform is also an aspect of the present invention. While discontinuous fiber prepregs have high shape conformability due to the discontinuous reinforcing fibers, they may break if large local deformation occurs. Therefore, by laminating the woven fabric or woven fabric prepreg of the present invention onto a discontinuous fiber prepreg, a preform with better shape conformability than a preform using a conventional woven fabric prepreg can be obtained. Meanwhile, the fiber bundles made of continuous carbon fibers contained in the woven fabric or woven fabric prepreg of the present invention can suppress large local deformation of the discontinuous fiber prepreg and prevent breakage. Furthermore, the mechanical properties derived from the continuous carbon fibers can be imparted to fiber-reinforced plastics.

[0028] The type of discontinuous fiber prepreg is not particularly limited, but examples include nonwoven fabric prepregs formed by impregnating a nonwoven fabric made of discontinuous fibers with resin, SMC (sheet molding compound), and slit prepregs formed by impregnating unidirectionally oriented continuous reinforcing fibers with resin and inserting slits to cut the continuous reinforcing fibers, etc. In particular, slit prepregs are preferred as the discontinuous fiber prepreg because they have an excellent balance between mechanical properties and shape conformability.

[0029] The incised prepreg will be described in more detail with reference to FIG. 2. FIG. 2 is a schematic diagram of the incised prepreg used in the examples described below. The incised prepreg 7 has reinforcing fibers 8 oriented in one direction, a resin impregnated into the reinforcing fibers 8, and incisions 9 for cutting the reinforcing fibers 8. The reinforcing fibers contained in the incised prepreg are not particularly limited, and carbon fibers, glass fibers, aramid fibers, alumina fibers, silicon carbide fibers, boron fibers, metal fibers, natural fibers, mineral fibers, etc. can be used. The matrix resin contained in the incised prepreg is not particularly limited, and the above-mentioned thermosetting resins and thermoplastic resins can be used. However, from the viewpoint of shape conformability, it is preferable that the matrix resins contained in the woven prepreg and the incised prepreg are the same type of resin (for example, a combination of epoxy resins, but not a combination of epoxy resin and polyamide). It is more preferable that they are the same resin (for example, a combination of epoxy resins, where the resin compositions of both resins are the same). In the incised prepreg, it is preferable that substantially all of the reinforcing fibers are cut by the incisions to form discontinuous fibers. The average fiber length of the reinforcing fibers contained in the incised prepreg is preferably 100 mm or less.

[0030] The preform of the present invention is preferably formed by laminating the incised prepreg on both sides of a woven prepreg, which is preferable because such lamination results in a fiber-reinforced plastic having high lightness and mechanical properties derived from the continuous carbon fiber, as well as a good appearance quality due to the reinforcing fibers being oriented in one direction.

[0031] [Fiber reinforced plastic] A fiber-reinforced plastic obtained by molding the woven fabric prepreg or preform of the present invention is also an aspect of the present invention. The fiber-reinforced plastic of the present invention has high mechanical properties derived from the continuous carbon fibers, even if it has a complex shape. [Example]

[0032] The present invention will be described in more detail below with reference to examples.

[0033] <Evaluation method> (1) Meandering rate measurement method The woven fabrics produced in the Examples and Comparative Examples were placed on a flat table, and a portion of each fiber bundle constituting the woven fabric was extracted so that the length of the line segment connecting the ends of the fiber bundles at the shortest distance was 100 mm, and the orientation direction of the fiber bundle was set. Next, one fiber bundle was arbitrarily selected, and all fiber bundles whose orientation direction intersected or was parallel to the orientation direction of the selected fiber bundle at an angle of 20° or less were extracted, and fiber bundle group A was set. At this time, the fiber bundle direction of fiber bundle group A was set as fiber bundle direction A. Next, one fiber bundle was arbitrarily selected from the fiber bundles contained in the woven fabric that did not belong to fiber bundle group A, and fiber bundles belonging to the same fiber bundle group as the selected fiber bundle were extracted using the same procedure as above, and fiber bundle group B was set. Next, 10 fiber bundles were randomly selected from each of fiber bundle group A and fiber bundle group B, and a portion of each selected fiber bundle was extracted so that the length of the line segment connecting the ends of the selected fiber bundle at the shortest distance was 100 mm or more. The meandering rate, which was expressed as [length of extracted fiber bundle] / [length of the line segment], was measured, and the average meandering rate and its coefficient of variation were calculated.

[0034] (2) How to confirm that the fiber bundles are meandering in the in-plane direction of the fabric For each of the fiber bundles contained in the woven fabrics produced in the Examples and Comparative Examples, a portion of 10 fiber bundles extracted in the same manner as in (1) was counted, and the number of fiber bundles judged to be meandering in the in-plane direction was counted, distinguishing between fiber bundle groups A and B. If 8 or more of the 10 fiber bundles were found to be meandering in the in-plane direction, the respective fiber bundle group was deemed to be meandering in the in-plane direction of the fabric.

[0035] (3) How to confirm that the fiber bundle meanders at a roughly constant pitch For each fiber bundle contained in the woven fabrics produced in the Examples and Comparative Examples, the coefficient of variation of the pitch was measured for some of the 10 fiber bundles extracted in (1), distinguishing between fiber bundle groups A and B, and if the coefficient of variation was 20% or less, it was considered that the fiber bundle meandered at a substantially constant pitch.

[0036] (4) How to confirm that the fiber bundle meanders at a substantially constant width For each fiber bundle contained in the woven fabrics produced in the Examples and Comparative Examples, the coefficient of variation of the width was measured for some of the 10 fiber bundles extracted in the same manner as in (1), distinguishing between fiber bundle groups A and B, and if the coefficient of variation was 20% or less, it was considered that the fiber bundle meandered at a substantially constant width.

[0037] (5) Shape followability evaluation The woven fabric prepregs prepared in the Examples and Comparative Examples were cut into 100 mm x 100 mm pieces and, if necessary, laminated with the incised prepregs prepared in the Examples to form preforms, yielding molded substrates. The molded substrates were then sandwiched between smooth metal plates and pressed for 20 minutes at a molding temperature of 150°C and a molding pressure of 3 MPa to obtain flat fiber-reinforced plastics. The resulting fiber-reinforced plastics were observed, and their elongation was calculated as [area of ​​the region containing the woven fabric in the fiber-reinforced plastic after molding] / [area of ​​the region containing the woven fabric in the woven fabric prepreg before molding] × 100 [%]. Here, the area of ​​the region containing the woven fabric was calculated as the area enclosed by a closed curve obtained by connecting the ends of the fiber bundles constituting the woven fabric with straight lines. The elongation serves as an index of the shape conformability of the molded substrate; a higher value indicates a higher shape conformability.

[0038] (6) Fiber bundle orientation evaluation The average meandering ratio of the fiber-reinforced plastics molded in the Examples and Comparative Examples was calculated using the following method. First, for each of the 10 fiber bundles belonging to fiber bundle group A and fiber bundle group B selected in (1), the shortest length connecting the ends of the fiber bundles contained in the fiber-reinforced plastic was measured, and the meandering ratio of the fiber bundle in the fiber-reinforced plastic was calculated from [length of the fiber bundle before molding] / [length of the shortest length connecting the ends of the fiber bundle after molding]. Then, for each of fiber bundle group A and fiber bundle group B, the average meandering ratio was calculated from the average value calculated for the 10 fiber bundles. The smaller the average meandering ratio of the fiber-reinforced plastic, the less meandering the fiber bundles contained in the fiber-reinforced plastic will be, and this is evaluated as preferable because it will result in superior appearance quality and mechanical properties as a molded product.

[0039] <Materials used> [Reinforced fiber] Carbon fiber 1 ("TORAYCA (registered trademark)" T700SC-12K, manufactured by Toray Industries, Inc.) Glass fiber 1 (ERS4800-317, manufactured by Central Glass Fiber Co., Ltd.) [Matrix resin] An epoxy resin (35 parts by weight of "jER®" 828, 30 parts by weight of "jER®" 1001, and 35 parts by weight of "jER®" 154, manufactured by Japan Epoxy Resins Co., Ltd.) was mixed with 5 parts by weight of thermoplastic resin polyvinyl formal ("Vinylec®" K, manufactured by Chisso Corporation) in a kneader to dissolve the polyvinyl formal uniformly. The mixture was then mixed with 3.5 parts by weight of curing agent dicyandiamide (DICY7, manufactured by Japan Epoxy Resins Co., Ltd.) and 4 parts by weight of curing accelerator 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU99, manufactured by Hodogaya Chemical Co., Ltd.) in a kneader to prepare an uncured epoxy resin composition. This epoxy resin composition was applied to silicone-coated release paper using a reverse roll coater to a basis weight of 50 g / m. 2 Resin film 1 was prepared.

[0040] [Textiles 1~3] Carbon fiber 1 was used as the fiber bundle of the present invention, and 150 mm x 150 mm woven fabrics were manually produced by meandering carbon fiber 1 to form a plain weave structure, to obtain woven fabrics 1 to 3 shown in Table 1. The characteristics of woven fabrics 1 to 3 are shown in Table 1. The fiber weight per unit area of ​​woven fabrics 1 to 3 was 50 g / m 2 It was.

[0041] [Textile 4] Carbon fiber 1 was used as the fiber bundle of the present invention, and a 150 mm x 150 mm woven fabric was manually produced so as to form a plain weave structure without meandering carbon fiber 1, to obtain woven fabric 4 shown in Table 1. The fiber weight of woven fabric 4 was 50 g / m 2 It was.

[0042] [Woven Prepreg 1-4] Resin film 1 was laminated on both sides of each of woven fabrics 1 to 4, and then sandwiched between metal plates heated to 100°C and pressed at a pressure of 0.5 MPa to impregnate the woven fabric with the resin, thereby obtaining woven fabric prepregs 1 to 4 shown in Table 1.

[0043] [Slit prepreg] The glass fiber prepreg was obtained by sandwiching the glass fiber 1 in one direction on both sides of the fiber substrate with the resin film 1, sandwiching it between metal plates heated to 100°C, and pressing it at a pressure of 0.5 MPa. The fiber weight of the fiber substrate was 100 g / m 2 Next, slits were made in the glass fiber prepreg to cut the glass fibers, to obtain slit prepreg 1 having an average fiber length of 20 mm. The slits were made as shown in Figure 2, with a length of 2 mm and an angle of 15° relative to the orientation direction of the glass fibers.

[0044] <Evaluation of woven prepreg> Example 1 Using woven prepreg 1 as the molding substrate, shape conformability and fiber bundle orientation were evaluated. The results are shown in Table 1.

[0045] Example 2 The shape conformability evaluation and fiber bundle orientation evaluation were carried out in the same manner as in Example 1, except that woven fabric prepreg 2 was used instead of woven fabric prepreg 1 as the molding substrate.

[0046] Example 3 The shape followability evaluation was carried out in the same manner as in Example 1, except that a preform formed by laminating incised prepreg 1 / woven prepreg 1 / incised prepreg 1 was used as the molding substrate.

[0047] (Comparative Example 1) The shape conformability evaluation and fiber bundle orientation evaluation were carried out in the same manner as in Example 1, except that woven fabric prepreg 4 was used instead of woven fabric prepreg 1 as the molding substrate.

[0048] (Comparative Example 2) The shape conformability evaluation and fiber bundle orientation evaluation were carried out in the same manner as in Example 1, except that woven fabric prepreg 3 was used instead of woven fabric prepreg 1 as the molding substrate.

[0049] [Table 1] [Explanation of symbols]

[0050] 1:Textile 2: Fiber bundle 3: Fiber bundle orientation direction 4: Fiber bundle group 5: End of fiber bundle 6: Apex of bend 7: Cut prepreg 8: Reinforced fiber 9: Cut

Claims

1. A woven fabric made of continuous fiber bundles of carbon fibers, wherein the average meandering ratio of the fiber bundles in at least one fiber bundle direction is 1.05 or more and 2.0 or less.

2. The woven fabric according to claim 1 , wherein the coefficient of variation of the meandering rate of the fiber bundle is 20% or less.

3. 3. The woven fabric according to claim 1, wherein the average meandering ratio in all fiber bundle directions is 1.05 or more and 2.0 or less.

4. The woven fabric according to claim 1 or 2, wherein the fiber bundles meander in the in-plane direction of the woven fabric.

5. The woven fabric according to claim 1 or 2, wherein the fiber bundles meander at a substantially constant pitch.

6. The woven fabric according to claim 1 or 2, wherein the fiber bundles meander with a substantially constant width.

7. 3. The woven fabric according to claim 1 or 2, which is a plain weave.

8. 3. The woven fabric according to claim 1, which is used in the production of fiber-reinforced plastics.

9. A woven fabric prepreg obtained by impregnating the woven fabric according to claim 1 with a resin.

10. The woven prepreg according to claim 9, wherein the resin is a thermosetting resin.

11. a discontinuous fiber prepreg containing discontinuous reinforcing fibers and a resin; A preform obtained by laminating the woven fabric according to claim 1 or the woven fabric prepreg according to claim 9.

12. The preform according to claim 11, wherein the discontinuous fiber prepreg is a cut prepreg formed by impregnating continuous reinforcing fibers oriented in one direction with a resin and providing a cut to cut the continuous reinforcing fibers.

13. The preform according to claim 12, wherein the incised prepreg is laminated on both sides of the woven fabric prepreg according to claim 9.

14. A fiber-reinforced plastic obtained by molding the woven fabric prepreg according to claim 9 or the preform according to claim 11.

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