JP6362454B2 - Mesh fiber reinforced composite - Google Patents

Description

  The present invention is excellent in breathability, prevents stuffiness and is lightweight and high in strength, and is basic for hats, various protectors, interior materials (inners) such as artificial limbs (prosthetic limbs, artificial hands), or exterior materials (frames). The present invention relates to a mesh-like fiber reinforced composite material for constituting a structure.

  Conventionally, for example, guards, station staff, police officers, etc. can wear as caps to protect their heads against unexpected fallen objects or external blows, etc. A hat with an inner that can be worn by an ordinary person as an exercise cap or the like to protect the head is proposed, and is commercially available.

  Patent Document 1 describes a cap 100 with a protective inner, as shown in FIGS. 7A and 7B attached to the present application. The cap 100 is a cap-shaped cap body (crown) made of cloth. ) 102 and a collar 103, and a protective inner 110 is provided inside the hat main body 102. Further, as shown in the figure, the protective inner 110 is fitted into the inside of the hat main body 102 and is curved in a substantially spherical shape so that it can be fitted to the human head when worn by the human. An inner body 111 having a basic inner structure made of a fiber reinforced resin material (FRP), which has a curved shape similar to the shape of the top region of the hat body 102, and the inner body 111 It is comprised by the cushion member 112 arrange | positioned inside and the cover sheet | seat 113 arrange | positioned so that the inner main body 111 and the cushion member 112 may be covered.

  The hat 100 with a protective inner described in Patent Document 1 is lightweight, has good air permeability, is excellent in impact resistance, and is excellent in wearability.

  However, in the hat 100 with a protective inner described in Patent Document 1, the inner main body 111 that forms the basic structure of the inner is made of a thermosetting resin or a thermoplastic resin in a reinforcing fiber that is unidirectional or woven. It is made of a fiber reinforced resin material (FRP) impregnated with a matrix resin and cured. Therefore, although it is lightweight and high-strength, it has been found that stuffiness may be felt when worn for a long time, and further improvement is desired in terms of air permeability. Further, as described above, the inner main body 111 has a substantially spherical curved shape so that it can be adapted to the human head, but the reinforcing fiber sheet that is unidirectional or woven is impregnated with resin. Although it is a cured fiber reinforced resin material (FRP), the reinforced fiber sheet that is unidirectional or woven before the resin impregnation has problems in terms of stretchability and draping, and is further improved in terms of moldability. Is desired.

  On the other hand, Patent Document 2 discloses a sheet-like carbon fiber knitted fabric knitted using carbon fibers, and describes that the sheet-like carbon fiber woven fabric is excellent in stretchability and drape. .

Utility Model Registration No. 3187008 Japanese Patent No. 4822528

  Therefore, the present inventors paid attention to the excellent stretchability and drapeability of the sheet-like carbon fiber knitted fabric described in Patent Document 2, and retained this sheet with the predetermined opening ratio possessed by the sheet-like carbon fiber knitted fabric. A mesh-like reinforced fiber composite material made by impregnating a carbon fiber woven fabric with a predetermined amount of resin and curing is used for interior materials (inners) such as hats, various protectors, artificial limbs (prosthetic legs, artificial hands), or exterior materials ( When used as a material for constituting a basic structure such as a frame, it has been found that it provides excellent breathability, can prevent stuffiness, and is lightweight and strong.

  The present invention has been made based on such novel findings of the present inventors.

  The object of the present invention is excellent in stretchability and draping, excellent in moldability to a curved shape, and excellent in breathability, prevents stuffiness, is lightweight and high in strength, hats, various protectors It is to provide a mesh-like fiber reinforced composite material for constituting a basic structure such as an interior material (inner) such as a prosthetic limb (prosthetic leg, prosthetic hand) or an exterior material (frame).

The above object is achieved by the mesh-like fiber reinforced composite material according to the present invention. In summary, according to one aspect of the present invention, a plurality of longitudinal knitting structures produced by knitting a chain stitch yarn while forming a chain stitch continuously in a longitudinal direction in a loop shape, A mesh-like knitted structure formed by an insertion yarn that is inserted laterally with respect to the knitted structure and binds the knitted structures adjacent to each other;
A mesh-like fiber-reinforced composite material shaped into a shape having a curved surface, which is cured by impregnating a resin only in the knitted structure and insertion yarn in the mesh-like knitted structure,
At least a part of the chain knitting yarn and the insertion yarn is a carbon fiber strand made of carbon fiber,
A mesh-like fiber reinforced composite material is provided, wherein the mesh-shaped knitted structure has an opening ratio of 20 to 60%.

According to another aspect of the present invention, a plurality of longitudinal knitting structures produced by knitting a chain knitting yarn while forming a chain stitch continuously in a longitudinal direction in a loop shape, and the longitudinal knitting structure A mesh-like knitted structure that is inserted in a transverse direction and is formed into a sheet formed by an insertion yarn that binds the knitting structures adjacent to each other;
A mesh-like fiber-reinforced composite material obtained by shaping the mesh-like knitted structure into a shape having a curved surface and then impregnating and curing only the knitted structure and insertion yarn in the mesh-like knitted structure. ,
At least a part of the chain knitting yarn and the insertion yarn is a carbon fiber strand made of carbon fiber,
A mesh-like fiber reinforced composite material is provided, wherein the mesh-shaped knitted structure has an opening ratio of 20 to 60%. According to one embodiment of the present invention, the resin impregnated in the mesh-shaped knitted structure is a room temperature curable or thermosetting epoxy resin, vinyl ester resin, MMA resin, acrylic resin, unsaturated polyester resin, Alternatively, a thermosetting resin such as a phenol resin; or a thermoplastic resin such as an epoxy resin, a polyamide resin, a polycarbonate resin, a polyetherimide resin, a polyether ether ketone resin, or a polyphenylene sulfide resin is used.

According to another aspect of the present invention, a plurality of longitudinal knitting structures produced by knitting a chain knitting yarn while forming a chain stitch continuously in a longitudinal direction in a loop shape, and the longitudinal knitting structure A mesh-like knitted structure that is inserted in a transverse direction and is formed into a sheet formed by an insertion yarn that binds the knitting structures adjacent to each other;
A mesh-like fiber reinforced composite material that is impregnated and cured only with the knitted structure and insertion yarn in the mesh-like knitted structure, and then shaped into a shape having a curved surface,
At least a part of the chain knitting yarn and the insertion yarn is a carbon fiber strand made of carbon fiber,
A mesh-like fiber reinforced composite material is provided, wherein the mesh-shaped knitted structure has an opening ratio of 20 to 60%. According to an embodiment of the present invention, the resin impregnated in the mesh-shaped knitted structure is a thermoplastic resin such as an epoxy resin, a polyamide resin, a polycarbonate resin, a polyether ether ketone resin, or a polyphenylene sulfide resin. Is done.

  In each of the present inventions described above, according to one embodiment, the insertion yarn is knitted by waving with respect to the knitted structure every certain course.

  In each of the present inventions described above, according to another embodiment, the number of carbon fiber filaments in the carbon fiber strand is 15000 or less, and the fineness of the carbon fiber strand is 1000 tex or less.

In each of the present invention, according to another embodiment, the chain knitting yarn and the insertion yarn which are not made into carbon fiber strands are polyester-based, polyamide-based, polyacrylonitrile-based, polyvinyl alcohol-based, polyolefin-based fiber, aramid fiber, etc. This is a yarn produced by mixing a plurality of organic fibers; metal fibers such as titanium fibers and steel fibers; and inorganic fibers such as glass fibers.

  The mesh-like fiber reinforced composite material of the present invention is excellent in stretchability and draping properties, and is excellent in moldability into a shape having a curved surface. Moreover, it has excellent breathability, can prevent stuffiness, is lightweight and has sufficient strength, and is used for interior materials (inners) such as hats, various protectors, artificial limbs (prosthetic legs, prosthetic hands), or exterior A basic structure such as a material (frame) can be formed.

FIG. 1A is a partial plan view showing an embodiment of a mesh-like knitted structure, and FIG. 1B is a schematic cross-sectional view for explaining a resin-impregnated state of the mesh-like knitted structure. . It is a fragmentary top view which shows the other Example of a mesh-shaped knitting structure. It is a fragmentary top view which shows the other Example of a mesh-shaped knitting structure. It is a fragmentary top view which shows the other Example of a mesh-shaped knitting structure. FIGS. 5A to 5E are views for explaining an embodiment of a method for forming a mesh-like fiber reinforced composite material of the present invention. 6 (a) and 6 (b) are diagrams for explaining another embodiment of the method for forming the mesh-like fiber reinforced composite material of the present invention. FIGS. 7A and 7B are diagrams showing an embodiment of a cap to which the mesh-like fiber reinforced composite material of the present invention can be applied as an inner material.

  Hereinafter, the mesh fiber reinforced composite material according to the present invention will be described in more detail with reference to the drawings.

Example 1
A mesh-like fiber reinforced composite material 10 according to the present invention has a mesh similar to that of a sheet-like carbon fiber knitted fabric described in Patent Document 2 (Patent No. 4822528) as shown in FIG. 1B. As shown in FIG. 1B, the mesh-like knitted structure is maintained while maintaining the mesh (gap) G formed in the mesh-like knitted structure 1 as shown in FIG. It is a mesh-like fiber reinforced composite material (FRP) obtained by impregnating the body 1 with resin R and curing. This mesh-like fiber reinforced composite material 10 is, for example, a hat as shown in FIG. 7, various other protectors, interior materials (inner) such as artificial limbs (prosthetic limbs, artificial hands), or basic materials such as exterior materials (frame). The molded product is shaped into a predetermined shape having at least a curved surface area for constituting the structure (sometimes simply referred to as “a shape having a curved surface” or “a predetermined shape”).

  More specifically, in this embodiment, the mesh-like knitted structure 1 is knitted as shown in FIG. 1A while the chain knitting yarns 2 are continuously formed in a loop shape in the longitudinal direction to form chain stitches 2A. And a plurality of longitudinally knitted fabrics 20 arranged in parallel, and an insertion yarn 3 for inserting the knitted fabrics 20 adjacent to each other in a lateral direction with respect to the longitudinal knitted fabrics 20. It is formed in a shape. The mesh-like knitted structure 1 is resin only in the knitted structure 20 and the insertion yarn 3 composed of the chain knitting yarns 2 in the mesh-like knitted structure 1 after shaping into a predetermined shape or before shaping as described above. Impregnated with R. That is, as will be described in detail later, the mesh-shaped knitted structure 1 is shaped into a predetermined shape, and then the resin R is impregnated only into the knitted structure 20 and the insertion yarn 3 in the mesh-shaped knitted structure 1 and cured. The mesh-shaped knitted structure 1 is first cured by impregnating only the knitted structure 20 and the insertion yarn 3 with the resin R, and then heat-molded. Thus, a mesh-like fiber reinforced composite material shaped into a predetermined shape is obtained. The mesh-shaped knitted structure 1 having the above-described configuration is excellent in drapeability, can be deep-drawn, and has a very simple forming operation when forming a composite material.

  That is, in the mesh-like fiber reinforced composite material 10 according to the present invention, since the mesh-like knitted structure 1 is a knitted fabric and the loop extends three-dimensionally, the fabric (mesh-like knitted structure 1) and its molded product (mesh-like) The fiber reinforced composite material 10) has a thickness that cannot be obtained with an FRP material molded using a woven fabric, and has a feature that the rigidity of a molded product (FRP) can be obtained by the thickness. On the other hand, in the woven fabric, the reinforcing fibers are easily flattened, and after molding, the fibers are flattened by the molding pressure, and the thickness of the molded product is reduced, resulting in no rigidity.

  In general, since the chain knitting yarn in the knitted base material exists in the most stable curved shape in the knitted fabric, high strength characteristics cannot be expected even with a fiber reinforced composite material. When knitting, each chain knitting yarn, which is a reinforcing fiber, is cured in a state of being stretched from the hemispherical apex to the radial shape (stretching direction) as it is shaped, especially for compression from the apex. On the other hand, it exhibits high strength and is optimal for molded products with curvature.

  Next, the mesh knitted structure 1 constituting the mesh fiber reinforced composite material 10 of the present invention will be further described.

(Mesh knitted structure)
In this embodiment, the mesh-like knitted structure 1 is a sheet-like carbon fiber knitted fabric having a mesh shape using carbon fiber bundles (carbon fiber strands) as the chain knitting yarn 2 and the insertion yarn 3. Fig.1 (a) is the elements on larger scale for demonstrating the sheet-like carbon fiber knitted fabric, especially the mesh-shaped knitted structure 1 used as a sheet-like carbon fiber warp knitted fabric.

  According to the present embodiment, the sheet-like knitted structure 1 is formed by arranging a large number of chain knitting yarns 2 made of carbon fiber strands in parallel while forming a continuous loop in the longitudinal direction (length direction of the sheet). A plurality of insertion yarns 3 made of carbon fiber strands (carbon fiber bundles) are knitted. In the present embodiment, the insertion yarns 3 are interlaced every three of the chain knitting yarns 2 and their directions are reversed (the guides are shaken by three stitches for each course) to form a warp knitted fabric.

  In this embodiment, in a mesh-like knitted structure (sheet material) 1 that is formed into a sheet shape, the carbon fiber strands of the chain knitting yarn 2 form a loop, and the insertion yarn 3 is knitted into the loop to be integrated. Therefore, for example, when the sheet material is pulled in the length direction, the loop expands, and the arrangement angle of the insertion thread 3 also changes accordingly, so that the sheet material can be easily stretched to be highly stretchable and draped. Is also rich. This drapability largely dominates the shapeability of complex curved surfaces. Since the mesh-like knitted structure is excellent in stretchability and drape, it can be shaped even on complex curved surfaces.

  In the mesh-like knitted structure 1, the carbon fiber strands (chain knitting yarns 2) form a loop, and the insertion yarns 3 are also arranged in two directions in a folded form, and the fibers are arranged in multiple directions as a whole. Therefore, when a composite material (FRP) is used, extreme anisotropy is not exhibited as in the case of a unidirectional material or a fabric. Therefore, for example, in the case of using a plurality of mesh-like knitted structures 1 in a stacked manner, a large number of mesh knitted structures 1 may be stacked in the same direction without being stacked while being shaped one by one so that the fiber axes are different. In addition, quasi-isotropic characteristics are obtained, and the molding operation is extremely simple.

  In the present embodiment, the knitted structure 20 in the mesh-like knitted structure 1 is formed because the chain knitting yarn 2 forms a loop in the longitudinal direction and the insertion yarn 3 is knitted into the loop and integrated. However, it is preferable that the fiber orientation is not disturbed during the laminating operation, but it is not limited to this. In addition to this, there are structures such as denbi, tulle, marquisette, and the insertion yarn 3 has an effect of preventing the ear portion from curling the ear portion of the fabric of the denbi tissue, for example. There are many combinations such as the presence or absence of. These may be appropriately designed depending on the intended use and usage pattern.

  Carbon fiber strands, that is, spun yarns obtained by spinning short fibers are also known as carbon fiber yarns. However, since the spun yarns are formed by strong twisting, they are highly converging and have a circular cross-sectional shape. Close to. The mesh-like knitted structure 1 knitted using such a chain knitting yarn 2 has a large number of voids, the surface of the knitted fabric is uneven, and the chain knitting yarn 3 is greatly bent. In addition, since the yarn is formed by spinning short fibers, the strength expression in the FRP is also reduced. Therefore, in the present invention, a continuous carbon fiber bundle in which a large number of continuous filaments are bundled is used.

  The carbon fiber used in this example is oxidized and flameproofed by heating a fiber bundle of polyacrylonitrile in an oxygen atmosphere, and carbonized in a high temperature inert gas under tension. It is a so-called PAN-based carbon fiber manufactured. Accordingly, although it depends on the processing conditions, it becomes a high-performance carbon fiber having a high strength and a high elastic modulus with a tensile strength of 3 to 10 GPa and a tensile elastic modulus of 200 to 600 GPa, and has uniform characteristics with little variation.

  The number of filaments and the fineness of the continuous carbon fiber strand used in this example are 15,000 and 1000 tex or less, for example, about 12,000 and 800 tex may be used. The portion where the knitting yarn 2 and the insertion yarn 3 intersect (location F in FIG. 1A) becomes thicker, while the knitting structure 20 has a void portion where no carbon fiber exists (in FIG. 1A). Since there is a portion G), the FRP has large irregularities. Accordingly, the number of filaments is preferably 6,000 or less (for example, in the range of 1,000 to 6,000), and the fineness of the carbon fiber strand is preferably 400 tex or less (for example, in the range of 60 to 400 tex).

Moreover, it is preferable that the carbon fiber basis weight per square meter of the mesh-like knitted structure 1 in the present embodiment is 100 to 700 g. When surface smoothness is required for the mesh-like fiber reinforced composite material 10 that is an FRP molded product, 100 to 300 g / m ² using fine carbon fiber strands, the mesh-like fiber reinforced composite material 10 has mechanical characteristics. When it is calculated | required or when the mesh-like fiber reinforced composite material 10 with thickness is calculated | required, it is preferable to set it as a fabric weight of 300-700 g / m < ² > using a thick carbon fiber strand. Further, if the basis weight is 100 g / m ² or less, the chain knit 2A has a large knitted fabric (mesh knitted structure 1), the gap G increases, and the mesh-like fiber reinforced composite material 10 has large irregularities, resulting in 700 g / m. ^{If it is 2} or more, the bending (crimp) of the carbon fiber strands will increase due to the crossing of the chain knitting yarns 2, 2 and the insertion yarn 3, and the mechanical properties of the mesh-like fiber reinforced composite material 10 will deteriorate due to the stress concentration. It is not preferable.

  In the mesh-like fiber reinforced composite material 10 in which the mesh-like knitted structure 1 of the present embodiment is laminated, when an impact force is applied, the carbon fiber is bent, so that it looks like a unidirectional material in which the carbon fibers are arranged straight. Immediately, a large load is not applied to the carbon fiber. First, the matrix resin R of the composite material 10 breaks and absorbs impact energy, and then the carbon fiber breaks, so that an FRP molded product having high impact resistance is obtained. .

  In order to further improve the impact resistance of FRP, it is preferable to use a resin having a high elongation at break in order to increase the impact absorption energy at the resin portion. In the case of thermoplastic resin, polyamide resin, polyetherimide resin, and polyetheretherketone resin are used. In the case of thermosetting resin such as epoxy resin and vinyl ester resin, high elongation at break is 4 to 10%. An elongation resin is preferred.

  Since the mesh-like knitted structure 1 of the present embodiment is a knitted fabric using carbon fiber strands that have already been carbonized, it becomes a fabric having a stable width as compared with a carbon fiber knitted fabric obtained by carbonizing a knitted fabric made of a precursor. It becomes a carbon fiber knitted fabric with a uniform basis weight, and a so-called high performance carbon fiber knitted fabric with high strength and high elastic modulus.

  The mesh-like knitted structure 1 is preferably produced by using a Russell knitting machine, in particular, adopting a method for producing a sheet-like carbon fiber knitted fabric described in Patent Document 2 (Patent No. 4822528). Furthermore, knitting can be performed using a tricot knitting machine, a crochet knitting machine, or the like. Since such a knitting manufacturing method is a method well known to those skilled in the art, further detailed description is omitted.

Modified example 1
The mesh-like knitted structure 1 used in the present invention is not limited to the above embodiment. That is, in the above embodiment shown in FIG. 1 (a), the insertion yarn 3 is crossed every three of the chain knitting yarns 2, and the directions are reversed (three stitches inserted per course), and the warp knitted fabric is Although formed, the configuration shown in FIGS. 2, 3, and 4 may be adopted.

  That is, in the embodiment shown in FIG. 2, the insertion yarn 3 intersects every two courses of the chain knitting yarn 2, and the directions are reversed (two needles are inserted per course). In the embodiment shown in FIG. Are mixed every two courses and the direction is reversed every two courses (two stitches inserted every three courses). In the embodiment of FIG. The courses are alternated every two courses, and the directions are reversed to reverse the direction (insertion of two needles every four courses and two courses) to form a warp knitted fabric.

Modified embodiment 2
In the said Example, the mesh-shaped knitting structure 1 demonstrated that all the chain knitting yarn 2 and the insertion yarn 3 used the thread | yarn produced with the carbon fiber strand. In addition, the carbon fiber strand is described as being a PAN-based carbon fiber.

  However, it is not necessary for the mesh-like knitted structure 1 to be entirely made of carbon fiber, that is, the chain knitting yarn 2 and the insertion yarn 3 constituting the mesh-like knitted structure 1 need to be made of carbon fiber strands. In addition, depending on the properties required for the mesh-like fiber reinforced composite material, that is, the strength, weight, etc., either the chain knitting yarn 2 or the insertion yarn 3 or a plurality of the chain knitting yarn 2 and the insertion yarn 3 to be used are used. A part of the inside can be replaced with another fiber. In other words, in other words, in the present invention, at least some of the chain knitting yarn 2 and the insertion yarn 3 are carbon fiber strands made of carbon fibers, and the remaining yarns are yarns made of fibers other than carbon fibers. Articles can be used.

Examples of fibers other than carbon fibers include polyester fibers, polyamide fibers, polyacrylonitrile fibers, polyvinyl alcohol fibers, polyolefin fibers, organic fibers such as aramid fibers , metal fibers such as titanium fibers and steel fibers, and glass fibers. Threads produced by mixing inorganic fibers alone or in combination of a plurality of types are used. The chain knitting yarn 2 and the insertion yarn 3 made of such fibers usually have a fineness of 10 to 600 tex, preferably 30 to 300 tex. When the fineness exceeds 600 tex, the yarn becomes thick, the portion where the chain knitting yarn 2 and the insertion yarn 3 cross each other becomes thick, and a composite material having large irregularities after the resin impregnation is obtained. In addition, it becomes difficult to maintain the drape and stretchability at high performance.

  In the above description, the PAN-based carbon fiber is used as the carbon fiber. However, the whole or a part of the PAN-based carbon fiber can be replaced with the pitch-based carbon fiber. When pitch-based carbon fibers are used, the number of carbon fiber filaments is 6000 or less, preferably 1000 to 3000, and the fineness of the carbon fiber strand is 600 tex or less, preferably 100 to 300 tex. It is preferable that When the number of carbon fiber filaments exceeds 6,000 and the fineness exceeds 600 tex, the carbon fiber strands become thick and the strength of the carbon fiber strands increases as described above, making it difficult to manufacture the mesh-like knitted structure 1 itself. In addition, the portion where the chain knitting yarn 2 and the insertion yarn 3 intersect with each other becomes thicker, resulting in a composite material 10 having large irregularities after impregnation with the resin, and maintaining high drape and stretchability. It becomes difficult.

(Aperture ratio)
In the present invention, the aperture ratio of the mesh-like fiber reinforced composite material 10 produced using the mesh-like knitted structure 1 is important. As described in detail later, the aperture ratio is preferably 20 to 60%, preferably Is 20 to 50%, more preferably 30 to 50%.

  According to the present invention, the mesh-like knitted structure 1 is impregnated with the resin R only in the knitted structure 20 formed by the chain knitting yarn 2 and the insertion yarn 3 in the mesh-like knitted structure 1 and cured. In other words, since the gap G of the mesh knitted structure 1 is not filled with resin, the opening ratio of the mesh-like fiber reinforced composite material 10 is substantially equal to the opening ratio of the mesh knitted structure 1. It is the same.

The aperture ratio generally means, for example, the rate of opening of holes in a plane used in screen-printed mesh fabric or punching metal, and in the present invention, the mesh shape The opening ratio of the knitted structure 1 means the rate of opening of holes in the plane of the mesh-like knitted structure 1. The mesh-like knitted structure 1 is read by a two-dimensional scanner, and the ratio is calculated based on the ratio of the portion with and without the fiber. Actually, it is read by a two-dimensional scanner, and the aperture ratio is calculated by dividing into a void portion and a fiber portion using image software. For example, such an aperture ratio can be efficiently obtained by using a two-dimensional scanner manufactured by Canon Inc. (trade name “CanoScan4400F”).
Opening ratio (%) = {(area of void portion) / (area of fiber portion + area of void portion)} × 100

  As described above, in the present invention, the aperture ratio of the mesh-like knitted structure 1 is set to 20 to 60%. When the opening ratio is less than 20%, the rigidity is very good, but the holes are not opened after molding, the air permeability is poor, and the weight becomes very heavy. When the opening ratio exceeds 60%, the air permeability is very good and the weight is light, but the amount of reinforcing fibers is insufficient as a whole and the rigidity is insufficient. Preferably, it is 20 to 50%, more preferably 30 to 50%.

In the present invention, in the mesh-like knitted structure 1, the size per opening (hole) is also important, and it is important that the area of each opening is ² to 80 mm ^2. is there. If the opening area per piece is less than 2 mm ² , holes may not be formed during molding, and if the opening area exceeds 80 mm ² , the mesh after molding becomes too large, and the mesh-like fiber reinforced composite There is a possibility that the rigidity as the material 10 is lost.

(Impregnated resin)
In the present invention, the mesh-shaped knitted structure 1 is cured by impregnating the resin R only in the knitted structure 20 and the insertion yarn 3 in the mesh-shaped knitted structure 1 after shaping into a predetermined shape or before shaping. Thus, the mesh-like fiber reinforced composite material 10 is obtained. The fiber content in the mesh-like fiber reinforced composite material 10 is 30 to 70%, preferably 40 to 60% in terms of the volume ratio of the fibers.

  In the above embodiment, examples of the thermoplastic resin include polyamide resin, polyetherimide resin and polyether ether ketone resin, and examples of the thermosetting resin include a room temperature curable type or a thermosetting type epoxy resin. Although vinyl ester resin etc. were illustrated, it is not limited to this. Furthermore, epoxy resin, polycarbonate resin, polyphenylene sulfide resin, etc. can be used as the thermoplastic resin, and MMA resin, acrylic resin, unsaturated polyester resin, phenol resin, etc. should be used as the thermosetting resin. Can do.

(Molding method)
Next, a method for forming the mesh fiber reinforced composite material 10 according to the present invention will be described.

  5A to 5C show a press molding method which is one embodiment of the molding method. According to this press molding method, the mesh knitted structure 1 is adapted to the convex male mold 201 and pressed, so that the mesh knitted structure 1 is molded following the male mold 201 (FIG. 5 ( a)). At this time, the mesh-like knitted structure 1 produced according to the present invention has good drape and stretchability, good moldability, and is easy to work as described above.

  Next, in order to impregnate the resin only in the knitting structure 20 composed of the chain knitting yarn 2 of the mesh-like knitting structure 1 and the insertion yarn 3, the impregnation brush (brush) or the like is used to impregnate the mesh-like knitting structure 1 with the resin. R is applied (FIG. 5B). The resin R may be a thermosetting resin or a thermoplastic resin. Thereafter, the concave female mold 202 is installed in conformity with the male mold 201, pressurized with a predetermined pressing force, and heated to cure the resin, and the mesh-like fiber reinforced composite material shaped into a predetermined shape. 10 is formed (FIG. 5C). The mesh-like fiber reinforced composite material 10 is taken out from the mold (FIG. 5D) and finished to a predetermined shape (FIG. 5E).

  6A and 6B show a vacuum forming method which is another embodiment of the forming method. According to this vacuum forming method, the mesh-like knitted structure 1 is a flat mesh-like knitted structure that is made into an FRP material by impregnating and curing only the knitted structure 20 composed of the chain knitting yarn 2 and the insertion yarn 3 with resin. A body 1a is formed. A thermoplastic resin is used as the resin.

  The mesh-like knitted structure 1a impregnated and cured with resin is placed on a concave vacuum mold (female mold) 202 and further covered with a resin film 60 (FIG. 6A). The female mold 202 is evacuated, and the male mold 201 is pressurized with a predetermined pressing force in accordance with the female mold 202 from the resin film 60 side and heated. As a result, the resin impregnated and hardened in the mesh-like knitted structure 1a is softened (melted) to be molded following the female mold 202. By cooling the mold, a mesh-like fiber reinforced composite material 10 shaped into a predetermined shape is obtained (FIG. 6B). Thereafter, as in the press molding method, as shown in FIGS. 5D and 5E, the mesh fiber reinforced composite material 10 is taken out of the mold and finished into a predetermined shape.

  Also in this vacuum molding method, the mesh-like knitted structure 1 when the resin is softened or melted has good drape and stretchability, good moldability, and is molded according to the male mold so that the work is easy. is there.

  According to the vacuum forming method, the holes of the mesh-like knitted structure 1 are not crushed at the time of molding, and the sheet thickness does not become thin at the time of molding, so that a composite material with a thick cross section is obtained and high strength is easily obtained. is there.

(Experimental Examples 1-5, Comparative Examples 1-5)
Next, in order to verify the effects of the mesh-like fiber reinforced composite material 10 and the mesh-like knitted structure 1 according to the present invention, the types of the chain knitting yarn 2 and the insertion yarn 3 of the mesh-like knitted structure 1, the opening ratio ( OR), etc. were changed to verify the strength, weight, breathability, etc. of the mesh fiber reinforced composite material 10. The experimental results are shown in Table 1. In this experimental example and comparative example, the fiber content in the composite material was 50% in terms of the fiber volume ratio.

Experimental example 1
The mesh-like knitted structure 1 used in Experimental Example 1 had the structure described with reference to FIG. The chain knitting yarn 2 and the insertion yarn 3 were PAN-based carbon fiber strands. The number of filaments of the carbon fiber strand was 3000, the fineness was 200 tex, and the carbon fiber basis weight was 600 g / m ² .

The aperture ratio of the mesh-like knitted structure 1 was determined using a two-dimensional scanner manufactured by Canon Inc. (trade name “CanoScan4400F”). The aperture ratio of the mesh-like knitted structure 1 of Experimental Example 1 was 20%. Moreover, the area of the opening part (hole) per piece was 2.5-3.0 mm < ² >.

  The mesh-like knitted structure 1 was formed by forming a mesh-like fiber-reinforced composite material 10 by the press molding method shown in FIG. That is, the mesh-shaped knitted structure 1 was set in a hemispherical male mold 201 having a single layer and a radius of 13 cm. The mesh-like knitted structure 1 had good drape and stretchability, good moldability, and was easy to work. Epoxy resin (manufactured by Nippon Steel & Sumikin Materials Co., Ltd., trade name “FR-E5P”) is applied to the mesh knitted structure 1 set in the male mold 201 with a brush, and the resin is applied only to the knitted structure 20 and the insertion yarn 3. Impregnated.

  Thereafter, the concave female mold 202 is installed in conformity with the male mold 201, pressurized with a predetermined pressing force (10 MPa), and heated (200 ° C.), whereby the resin is cured and shaped into a predetermined shape. A mesh-like fiber reinforced composite material 10 was obtained. The mesh fiber reinforced composite material 10 was taken out from the mold and finished in a predetermined shape.

  The strength of the mesh-like fiber reinforced composite material 10 was evaluated with a universal testing machine one week after molding. The evaluation machine was a Shimadzu universal testing machine (10 ton compatible), and the evaluation method was compression, test speed: 10 mm / min. A silicon jig having a diameter of 10 cm was used for the indenter. The maximum load value of the compression test was read. The load value was 5.5 kN, and the weight was 54 g. It was worn on the head under clear sky for about 2 hours, but no sweat was observed inside.

Experimental example 2
The mesh-like knitted structure 1 used in Experimental Example 2 is the same as that in Experimental Example 1, and the chain knitting yarn 2 and the insertion yarn 3 were PAN-based carbon fiber strands. The number of filaments of the carbon fiber strand was 3000, the fineness was 200 tex, and the carbon fiber basis weight was 400 g / m ² .

The aperture ratio of the mesh knitted structure 1 obtained in the same manner as in Experimental Example 1 was 40%. Moreover, the area of the opening part per piece was 4.0-4.5 mm < ² >.

  The mesh-like knitted structure 1 was obtained by forming the mesh-like fiber-reinforced composite material 10 by the press molding method in the same manner as in Experimental Example 1. That is, the mesh-shaped knitted structure 1 was set in a hemispherical male mold 201 having a single layer and a radius of 13 cm. The mesh-like knitted structure 1 had good drape and stretchability, good moldability, and was easy to work. Epoxy resin (manufactured by Nippon Steel & Sumikin Materials Co., Ltd., trade name “FR-E5P”) is applied to the mesh knitted structure 1 set in the male mold 201 with a brush, and the resin is applied only to the knitted structure 20 and the insertion yarn 3. Impregnated.

  Thereafter, the concave female mold 202 is installed in conformity with the male mold 201, pressurized with a predetermined pressing force (10 MPa), and heated (200 ° C.), whereby the resin is cured and shaped into a predetermined shape. A mesh-like fiber reinforced composite material 10 was obtained. The mesh fiber reinforced composite material 10 was taken out from the mold and finished in a predetermined shape.

  The strength of the mesh-like fiber reinforced composite material 10 was evaluated with a universal testing machine one week after molding. The evaluation machine was a Shimadzu universal testing machine (10 ton compatible), and the evaluation method was compression, test speed: 10 mm / min. A silicon jig having a diameter of 10 cm was used for the indenter. The maximum load value of the compression test was read. The load value was 4.3 kN, and the weight was 39 g. It was worn on the head under clear sky for about 2 hours, but no sweat was observed inside.

Experimental example 3
The mesh-like knitted structure 1 used in Experimental Example 3 is the same as in Experimental Example 1, and the chain knitting yarn 2 and the insertion yarn 3 were PAN-based carbon fiber strands. The number of filaments of the carbon fiber strand was 3000, the fineness was 200 tex, and the carbon fiber basis weight was 300 g / m ² .

The aperture ratio of the mesh-like knitted structure 1 obtained in the same manner as in Experimental Example 1 was 60%. The area of the openings per one was 8.5~9.0mm ^2.

  The mesh-like knitted structure 1 was obtained by forming the mesh-like fiber-reinforced composite material 10 by the press molding method in the same manner as in Experimental Example 1. That is, the mesh-shaped knitted structure 1 was set in a hemispherical male mold 201 having a single layer and a radius of 13 cm. The mesh-like knitted structure 1 had good drape and stretchability, good moldability, and was easy to work. Epoxy resin (manufactured by Nippon Steel & Sumikin Materials Co., Ltd., trade name “FR-E5P”) is applied to the mesh knitted structure 1 set in the male mold 201 with a brush, and the resin is applied only to the knitted structure 20 and the insertion yarn 3. Impregnated.

  Thereafter, the concave female mold 202 is installed in conformity with the male mold 201, pressurized with a predetermined pressing force (10 MPa), and heated (200 ° C.), whereby the resin is cured and shaped into a predetermined shape. A mesh-like fiber reinforced composite material 10 was obtained. The mesh fiber reinforced composite material 10 was taken out from the mold and finished in a predetermined shape.

  The strength of the mesh-like fiber reinforced composite material 10 was evaluated with a universal testing machine one week after molding. The evaluation machine was a Shimadzu universal testing machine (10 ton compatible), and the evaluation method was compression, test speed: 10 mm / min. A silicon jig having a diameter of 10 cm was used for the indenter. The maximum load value of the compression test was read. The load value was 3.0 kN and the weight was 29 g. It was worn on the head under clear sky for about 2 hours, but no sweat was observed inside. However, the compressive strength was about ½ compared to Experimental Example 1.

Experimental Example 4
The mesh-like knitted structure 1 used in Experimental Example 4 had the structure described with reference to FIG. A knitted structure 20 was formed with chain knitting yarn 2 using vinylon fibers. The number of filaments of the chain knitting yarn 2 was 250, and the fineness was 56 tex. As the insertion yarn 3, a PAN-based carbon fiber strand was used. The carbon fiber strand had 3000 filaments and a fineness of 200 tex. The fiber basis weight of the mesh-like knitted structure 1 was 450 g / m ² .

The aperture ratio of the mesh-like knitted structure 1 was calculated and calculated using a two-dimensional scanner (trade name “CanoScan4400F”) manufactured by Canon Inc. The aperture ratio of the mesh-like knitted structure 1 of Experimental Example 4 was 40%. Moreover, the area of the opening part per piece was 4.5-5.0 mm < ² >.

  The mesh-like knitted structure 1 was obtained by forming the mesh-like fiber-reinforced composite material 10 by the press molding method in the same manner as in Experimental Example 1. That is, the mesh-shaped knitted structure 1 was set in a hemispherical male mold 201 having a single layer and a radius of 13 cm. The mesh-like knitted structure 1 had good drape and stretchability, good moldability, and was easy to work. Epoxy resin (manufactured by Nippon Steel & Sumikin Materials Co., Ltd., trade name “FR-E5P”) is applied to the mesh knitted structure 1 set in the male mold 201 with a brush, and the resin is applied only to the knitted structure 20 and the insertion yarn 3. Impregnated.

  Thereafter, the concave female mold 202 is installed in conformity with the male mold 201, pressurized with a predetermined pressing force (10 MPa), and heated (200 ° C.), whereby the resin is cured and shaped into a predetermined shape. A mesh-like fiber reinforced composite material 10 was obtained. The mesh fiber reinforced composite material 10 was taken out from the mold and finished in a predetermined shape.

  The strength of the mesh-like fiber reinforced composite material 10 was evaluated with a universal testing machine one week after molding. The evaluation machine was a Shimadzu universal testing machine (10 ton compatible), and the evaluation method was compression, test speed: 10 mm / min. A silicon jig having a diameter of 10 cm was used for the indenter. The maximum load value of the compression test was read. The load value was 4.2 kN, and the weight was 38 g. It was worn on the head under clear sky for about 2 hours, but no sweat was observed inside.

Experimental Example 5
The mesh-like knitted structure 1 used in Experimental Example 5 had the structure described with reference to FIG. A knitted structure 20 was formed with chain knitting yarn 2 using vinylon fibers. The number of filaments of the chain knitting yarn 2 was 250, and the fineness was 56 tex.

  The insertion thread 3 is composed of a first insertion thread 3a and a second insertion thread 3b. The first insertion thread 3a uses vinylon fibers, and the second insertion thread 3b uses PAN-based carbon fiber strands. . The number of filaments of the vinylon yarn of the first insertion yarn 3a was 250 and the fineness was 56 tex, and the number of filaments of the carbon fiber strand of the second insertion yarn 3b was 3000 and the fineness was 200 tex.

The fiber basis weight of the mesh-like knitted structure 1 was 450 g / m ² .

The aperture ratio of the mesh-like knitted structure 1 was calculated and calculated using a two-dimensional scanner (trade name “CanoScan4400F”) manufactured by Canon Inc. The aperture ratio of the mesh-like knitted structure 1 of Experimental Example 4 was set to 35%. Moreover, the area of the opening part per piece was 3.5-4.0 mm < ² >.

  The mesh-like knitted structure 1 was obtained by forming the mesh-like fiber-reinforced composite material 10 by the press molding method in the same manner as in Experimental Example 1. That is, the mesh-shaped knitted structure 1 was set in a hemispherical male mold 201 having a single layer and a radius of 13 cm. The mesh-like knitted structure 1 had good drape and stretchability, good moldability, and was easy to work. Epoxy resin (manufactured by Nippon Steel & Sumikin Materials Co., Ltd., trade name “FR-E5P”) is applied to the mesh knitted structure 1 set in the male mold 201 with a brush, and the resin is applied only to the knitted structure 20 and the insertion yarn 3. Impregnated.

  Thereafter, the concave female mold 202 is installed in conformity with the male mold 201, pressurized with a predetermined pressing force (10 MPa), and heated (200 ° C.), whereby the resin is cured and shaped into a predetermined shape. A mesh-like fiber reinforced composite material 10 was obtained. The mesh fiber reinforced composite material 10 was taken out from the mold and finished in a predetermined shape.

  The strength of the mesh-like fiber reinforced composite material 10 was evaluated with a universal testing machine one week after molding. The evaluation machine was a Shimadzu universal testing machine (10 ton compatible), and the evaluation method was compression, test speed: 10 mm / min. A silicon jig having a diameter of 10 cm was used for the indenter. The maximum load value of the compression test was read. The load value was 4.1 kN, and the weight was 33 g. It was worn on the head under clear sky for about 2 hours, but no sweat was observed inside.

Comparative Example 1
In Comparative Example 1, 2,2 twill cloth using PAN-based carbon fiber strands was used. The number of filaments of the carbon fiber strand was 3000, the fineness was 200 tex, and the carbon fiber basis weight was 200 g / m ² .

  The twill weave cloth was set in a single layer, a hemispherical male mold 201 having a radius of 13 cm, as in Experimental Example 1. The twill cloth had poor drape and stretchability, poor moldability, and was difficult to work with. The twill weave cloth set in the male mold 201 was impregnated with epoxy resin (manufactured by Nippon Steel & Sumikin Materials Co., Ltd., trade name “FR-E5P”). Thereafter, the twill weave cloth having the same configuration was covered as the second layer, and the same resin was impregnated as in the first layer.

  Thereafter, the concave female mold 202 is installed in conformity with the male mold 201, pressurized with a predetermined pressing force (10 MPa), and heated (200 ° C.), whereby the resin is cured and shaped into a predetermined shape. A fiber reinforced composite material was obtained. The fiber reinforced composite material was taken out from the mold and finished into a predetermined shape.

  The strength of the fiber reinforced composite material was evaluated with a universal testing machine one week after molding. The evaluation machine was a Shimadzu universal testing machine (10 ton compatible), and the evaluation method was compression, test speed: 10 mm / min. A silicon jig having a diameter of 10 cm was used for the indenter. The maximum load value of the compression test was read. The load value was 6.2 kN, and the weight was 72 g. It was worn on the head under clear sky for about 2 hours, but a small amount of sweat was observed inside.

Comparative Example 2
In Comparative Example 2, a fiber reinforced composite material shaped into a predetermined shape was produced in the same manner as in Comparative Example 1. On the fiber reinforced composite material, the next day after molding, 10 circular holes having a diameter of 1.85 cm were formed in the obtained molded product.

  The molded product was evaluated for strength one week after molding with a universal testing machine. The evaluation machine was a Shimadzu universal testing machine (10 ton compatible), and the evaluation method was compression, test speed: 10 mm / min. A silicon jig having a diameter of 10 cm was used for the indenter. The maximum load value of the compression test was read. The load value was 3.0 kN and the weight was 62 g. I put it on my head under clear sky for about 2 hours. Although not as much as in Comparative Example 1, generation of sweat was observed inside.

Comparative Example 3
In Comparative Example 3, a fiber reinforced composite material shaped into a predetermined shape was produced in the same manner as in Comparative Example 1. On the fiber reinforced composite material, 20 holes having a diameter of 1.85 cm were formed in the obtained molded product the day after molding.

  The molded product was evaluated for strength one week after molding with a universal testing machine. The evaluation machine was a Shimadzu universal testing machine (10 ton compatible), and the evaluation method was compression, test speed: 10 mm / min. A silicon jig having a diameter of 10 cm was used for the indenter. The maximum load value of the compression test was read. The load value was 2.0 kN, and the weight was 50 g. It was worn on the head under clear sky for about 2 hours, but no sweat was observed inside.

Comparative Example 4
In Comparative Example 4, a 2,2 twill cloth using PAN-based carbon fiber strands was used. The number of filaments of the carbon fiber strand was 3000, the fineness was 200 tex, and the carbon fiber basis weight was 200 g / m ² .

In the same manner as in Comparative Example 1, the twill weave cloth was set in a hemispherical male mold 201 having a radius of 13 cm. The twill cloth had poor drape and stretchability, poor moldability, and was difficult to work with. The twill weave cloth set in the male mold 201 was impregnated with epoxy resin (manufactured by Nippon Steel & Sumikin Materials Co., Ltd., trade name “FR-E5P”). After that, unlike Comparative Example 1, instead of 2,2 twill cloth using PAN-based carbon fiber strands, a vinylon plain weave cloth (Unitika Ltd., trade name “Bistron plain weave cloth VH205”) was used. . The raw yarn fineness was length, width 1670 dtex, density warp, width 16 pieces / 25 mm, and fiber basis weight was 205 g / m ² .

  Also in Comparative Example 4, a fiber-reinforced composite material shaped into a predetermined shape was produced in the same manner as Comparative Example 1. On the fiber reinforced composite material, 20 holes having a diameter of 1.85 cm were formed in the obtained molded product the day after molding.

  The molded product was evaluated for strength one week after molding with a universal testing machine. The evaluation machine was a Shimadzu universal testing machine (10 ton compatible), and the evaluation method was compression, test speed: 10 mm / min. A silicon jig having a diameter of 10 cm was used for the indenter. The maximum load value of the compression test was read. The load value was 1.8 kN, and the weight was 49 g. It was worn on the head under clear sky for about 2 hours, but no sweat was observed inside.

Comparative Example 5
In Comparative Example 5, molding was performed in the same manner as in Comparative Example 1, and 40 circular holes with a diameter of 1.85 cm were formed in the molded product obtained the next day.

  The molded product was evaluated for strength one week after molding with a universal testing machine. The evaluation machine was a Shimadzu universal testing machine (10 ton compatible), and the evaluation method was compression, test speed: 10 mm / min. A silicon jig having a diameter of 10 cm was used for the indenter. The maximum load value of the compression test was read. The load value was 1.0 kN, and the weight was 45 g. It was worn on the head under clear sky for about 2 hours, but no sweat was observed inside. However, the compressive strength was 1/6 as compared with Comparative Example 1.

Comparative Example 6
In Comparative Example 6, molding was performed in the same manner as in Comparative Example 1, and 60 circular holes having a diameter of 1.85 cm were formed in the molded product obtained the next day.

  The molded product was evaluated for strength one week after molding with a universal testing machine. The evaluation machine was a Shimadzu universal testing machine (10 ton compatible), and the evaluation method was compression, test speed: 10 mm / min. A silicon jig having a diameter of 10 cm was used for the indenter. The maximum load value of the compression test was read. The load value was 0.5 kN, and the weight was 35 g. It was worn on the head under clear sky for about 2 hours, but no sweat was observed inside. However, the compressive strength was 1/12 compared to Comparative Example 1.

DESCRIPTION OF SYMBOLS 1 Mesh-like knitting structure 2 Chain knitting yarn 2A Chain knitting stitch 3 Insertion yarn 10 Mesh-like fiber reinforced composite material 20 Knitting structure

Claims (8)

A plurality of longitudinal knitting structures produced by knitting a chain knitting yarn while forming a chain stitch continuously in a longitudinal direction in a loop, and inserted in the transverse direction with respect to the longitudinal knitting structure, An insertion yarn that binds adjacent knitted structures, and a mesh-like knitted structure formed by:
A mesh-like fiber-reinforced composite material shaped into a shape having a curved surface, which is cured by impregnating a resin only in the knitted structure and insertion yarn in the mesh-like knitted structure,
At least a part of the chain knitting yarn and the insertion yarn is a carbon fiber strand made of carbon fiber,
A mesh-like fiber-reinforced composite material, wherein the mesh-like knitted structure has an opening ratio of 20 to 60%. A plurality of longitudinal knitting structures produced by knitting a chain knitting yarn while forming a chain stitch continuously in a longitudinal direction in a loop, and inserted in the transverse direction with respect to the longitudinal knitting structure, An insertion yarn that binds adjacent knitted structures, and a mesh-like knitted structure formed into a sheet shape,
A mesh-like fiber-reinforced composite material obtained by shaping the mesh-like knitted structure into a shape having a curved surface and then impregnating and curing only the knitted structure and insertion yarn in the mesh-like knitted structure. ,
At least a part of the chain knitting yarn and the insertion yarn is a carbon fiber strand made of carbon fiber,
A mesh-like fiber-reinforced composite material, wherein the mesh-like knitted structure has an opening ratio of 20 to 60%.   The resin impregnated in the mesh-shaped knitted structure is a thermosetting resin such as a room temperature curing type or thermosetting type epoxy resin, vinyl ester resin, MMA resin, acrylic resin, unsaturated polyester resin, or phenol resin. Or a thermoplastic resin such as an epoxy resin, a polyamide resin, a polycarbonate resin, a polyetherimide resin, a polyetheretherketone resin, or a polyphenylene sulfide resin is used. Mesh fiber reinforced composite. A plurality of longitudinal knitting structures produced by knitting a chain knitting yarn while forming a chain stitch continuously in a longitudinal direction in a loop, and inserted in the transverse direction with respect to the longitudinal knitting structure, An insertion yarn that binds adjacent knitted structures, and a mesh-like knitted structure formed into a sheet shape,
A mesh-like fiber reinforced composite material that is impregnated and cured only with the knitted structure and insertion yarn in the mesh-like knitted structure, and then shaped into a shape having a curved surface,
At least a part of the chain knitting yarn and the insertion yarn is a carbon fiber strand made of carbon fiber,
A mesh-like fiber-reinforced composite material, wherein the mesh-like knitted structure has an opening ratio of 20 to 60%.   5. The resin impregnated in the mesh-like knitted structure is a thermoplastic resin such as an epoxy resin, a polyamide resin, a polycarbonate resin, a polyether ether ketone resin, or a polyphenylene sulfide resin. A mesh-like fiber reinforced composite material according to 1.   The mesh-like fiber-reinforced composite material according to any one of claims 1 to 5, wherein the insertion yarn is knitted while being shaken with respect to the knitted structure for each predetermined course.   The mesh-like fiber-reinforced composite material according to any one of claims 1 to 6, wherein the carbon fiber strand has 15,000 or less carbon fiber filaments and the fineness of the carbon fiber strand is 1000 tex or less. . The chain knitting yarn and the insertion yarn which are not made into carbon fiber strands are polyester fibers, polyamide fibers, polyacrylonitrile fibers, polyvinyl alcohol fibers, polyolefin fibers, organic fibers such as aramid fibers; metal fibers such as titanium fibers and steel fibers; The mesh-like fiber-reinforced composite material according to any one of claims 1 to 7, wherein the mesh-like fiber-reinforced composite material is a yarn produced by mixing inorganic fibers such as glass fibers alone or by mixing plural kinds thereof.

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