JP6938987B2 - Method for manufacturing reinforcing fiber base material, manufacturing method for reinforcing fiber preform, and manufacturing method for fiber reinforced composite material molded product - Google Patents

Description

The present invention relates to a method for producing a reinforcing fiber base material, a method for producing a reinforcing fiber preform using the reinforcing fiber base material, and a method for producing a fiber-reinforced composite material molded product using the reinforcing fiber preform.

A fiber-reinforced composite material molded body (FRP molded body) obtained by molding a fiber-reinforced composite material (FRP) in which reinforcing fibers are impregnated with a matrix resin satisfies required properties such as excellent mechanical properties and weight reduction. For this reason, FRP molded products have been mainly used in the fields of aviation, space, and sports.

An autoclave molding method is known as a typical manufacturing method of an FRP molded body. In such a molding method, a prepreg in which a reinforcing fiber bundle is pre-impregnated with a matrix resin is laminated on a molding mold, and then heated and pressed by an autoclave to produce an FRP molded product. Regarding the process of laminating prepregs, in addition to the method of cutting out a desired shape from a sheet-shaped prepreg and laminating by hand, from the viewpoint of improving the material yield and saving labor in the process, automatic as shown in Patent Document 1 A method of laminating tape-shaped prepregs using a laminating device is known.

On the other hand, as a molding method having excellent productivity of the FRP molded body, for example, an injection molding method such as a resin transfer molding molding method (RTM) can be mentioned. In the RTM molding method, a reinforcing fiber base material composed of a dry reinforcing fiber bundle that is not pre-impregnated with a matrix resin is laminated on a molding mold, and a liquid, low-viscosity matrix resin is injected into the matrix resin. This is a molding method for molding an FRP molded product by impregnating and solidifying. Further, in the injection molding method, a preforming step of deforming and fixing the reinforcing fiber base material into a rough product shape is often performed before filling the molding mold. In the preforming step, by using the technique of arranging the thermoplastic polymer material between the layers of the reinforcing fiber base material as shown in Patent Document 2, the mechanical properties of the FRP molded body obtained by fixing the preform and RTM molding are used. Many technologies have been proposed to improve (impact resistance, etc.).

Japanese Unexamined Patent Publication No. 2012-6400 Japanese Patent Application Laid-Open No. 2008-540766

When a reinforcing fiber is directly and automatically laminated on a three-dimensional molded mold using an automatic laminating device as shown in Patent Document 1 to manufacture an FRP molded product, automatic laminating depends on the complexity of the three-dimensional shape in the molding die. There is a problem that the operating speed of the device cannot be increased and the productivity cannot be increased. In order to increase productivity, an FRP molded body is manufactured by shaping a planar reinforcing fiber base material laminate produced by laminating reinforcing fibers in advance and heat-welding them into a three-dimensional reinforcing fiber preform. There is a way to do it. However, the reinforcing fiber base material laminate produced by laminating and heat welding has high rigidity because the respective layers are strongly adhered to each other, and thus is shaped from a planar shape to a three-dimensional reinforcing fiber preform. When this is done, there is a problem that the followability to a complicated three-dimensional shape is low and defects such as wrinkles are likely to occur. Further, when a technique as shown in Patent Document 2 is used in order to fix the preform and improve the mechanical properties of the RTM molded product, the thermoplastic polymer material which is a thermoplastic resin is melted at the time of heat welding. This covers the surface of the reinforcing fiber bundle and blocks the flow path of the matrix resin injected in the resin injection step, so that defects such as non-impregnation of the matrix resin are likely to occur.

In addition, a method of producing a flat-shaped reinforcing fiber base material one layer at a time, transporting the reinforcing fiber base material one layer at a time onto a three-dimensional mold, and then shaping the reinforcing fiber preform to produce an FRP molded product. Can also be mentioned. However, when the reinforcing fiber bundle constituting the reinforcing fiber base material used in such a manufacturing method is in a form in which the tape-shaped reinforcing fiber bundles are simply aligned in one direction, the reinforcing fiber bundles are orthogonal to the fiber axial direction of the reinforcing fibers. Since there is no binding force in the direction of the reinforcing fiber or it is very weak, the position of the reinforcing fiber bundle and the fiber orientation may be lost when the reinforcing fiber base material is conveyed.

The present invention solves the problems of the prior art, and not only has an excellent yield of the reinforcing fiber bundle, but also has ease of handling during transportation (particularly, morphological stability of the reinforcing fiber base material) and preform shaping. An object of the present invention is to provide a method for producing a reinforcing fiber base material having excellent shapeability in a process. In addition, a method for producing a reinforced fiber preform, which has good impregnation property of a matrix resin and is excellent in mechanical properties such as impact resistance, particularly CAI, which is a compressive strength after impact is applied, and a method for producing a fiber reinforced composite material molded product. It is intended to be provided.

The present invention employs the following means in order to solve at least a part of such problems. That is, the present invention is as follows.
[Form 1] A method for producing a reinforcing fiber base material, in which at least one reinforcing fiber bundle is repeatedly placed on a table having a temporary fixing means by aligning the reinforcing fiber bundle from the reinforcing fiber bundle mounting head. On the fiber bundle layer forming step and the reinforcing fiber bundle, polyamide resin, polyester resin, polyphenylene sulfide resin, polyetherimide resin, polyether sulfone resin, polyvinylformal resin, polyether ether ketone resin, polycarbonate resin, polysulfone. A mesh-like resin material sheet arranging step of arranging a mesh-like resin material sheet composed of at least one selected from a resin, a polyphenylene ether resin, a polyimide resin, a polyamideimide resin, and a phenoxy resin or a mixture thereof, and the mesh-like resin material sheet. A bonding step of at least partially adhering the reinforcing fiber bundle to the reinforcing fiber bundle is provided, and in the reinforcing fiber bundle layer forming step, the placement interval between the reinforcing fiber bundles is larger than 0 mm (mm) and 2 mm or less. A method for producing a reinforcing fiber base material.
In addition, the present invention can be realized by the following forms.

(1) A method for producing a reinforcing fiber base material, which is a polyamide resin, a polyester resin, a polyphenylene sulfide resin, a polyetherimide resin, a polyether sulfone resin, a polyvinyl formal resin, and a polyether ether on a table having a temporary fixing means. A mesh-like resin material sheet arrangement step for arranging a mesh-like resin material sheet composed of at least one selected from a ketone resin, a polycarbonate resin, a polysulfone resin, a polyphenylene ether resin, a polyimide resin, a polyamideimide resin, and a phenoxy resin, or a mixture thereof. A step of forming a reinforcing fiber bundle layer in which at least one reinforcing fiber bundle is repeatedly aligned and placed on the mesh-like resin material sheet from the reinforcing fiber bundle mounting head, and the mesh-like resin material sheet. A method for producing a reinforcing fiber base material, comprising an bonding step of at least partially adhering the reinforcing fiber bundle to the reinforcing fiber bundle.

According to the method for producing a reinforcing fiber base material according to (1), not only the yield of the reinforcing fiber bundle is excellent, but also the handleability during transportation (particularly, the morphological stability of the reinforcing fiber base material) and the preform are added. A reinforcing fiber base material having excellent shapeability in the shaping process is produced.

(2) A method for producing a reinforcing fiber base material, in which at least one reinforcing fiber bundle is repeatedly placed on a table having a temporary fixing means by aligning the reinforcing fiber bundle from the reinforcing fiber bundle mounting head. On the bundle layer forming step and the reinforcing fiber bundle, a polyamide resin, a polyester resin, a polyphenylene sulfide resin, a polyetherimide resin, a polyether sulfone resin, a polyvinylformal resin, a polyether ether ketone resin, a polycarbonate resin, and a polyether sulfone resin. , Polyphenylene ether resin, polyimide resin, polyamideimide resin, and phenoxy resin. A method for producing a reinforcing fiber base material, comprising an bonding step of at least partially adhering the reinforcing fiber bundle.

According to the method for producing a reinforcing fiber base material according to (2), the same effect as the method for producing a reinforcing fiber base material according to (1) can be obtained.

(3) In the method for producing a reinforcing fiber base material according to (1), in the reinforcing fiber bundle layer forming step, a color tone difference between the table and the mesh-like resin material sheet is detected, and the color tone difference is obtained. A method for producing a reinforcing fiber base material, wherein the reinforcing fiber bundle is placed at a detected position as a start point and an end point at which the reinforcing fiber bundle is placed.

According to the method for producing a reinforcing fiber base material according to (3), if the mesh-like resin material sheet is cut into a desired shape in advance, it is only necessary to specify the placement interval corresponding to the width of the reinforcing fiber bundle. , It is possible to create a reinforcing fiber base material having an arbitrary shape without performing the coordinate input work.

(4) The method for producing a reinforcing fiber base material according to (1) to (3), wherein the binder resin is attached to the surface of the reinforcing fiber bundle. Production method.

According to the method for producing a reinforcing fiber base material according to (4), the width stability of the reinforcing fiber bundle is brought about, so that a reinforcing fiber base material having excellent stability of gaps and basis weights of adjacent reinforcing fiber bundles can be obtained. Is possible.

(5) The method for producing a reinforcing fiber base material according to (4), wherein the basis weight of the binder resin is 1 to 20 parts by weight when the basis weight of the reinforcing fiber bundle is 100 parts by weight. A method for manufacturing a reinforcing fiber base material.

According to the method for producing a reinforcing fiber base material according to (5), it is possible to obtain a reinforcing fiber base material having more excellent stability of gaps and basis weights of adjacent reinforcing fiber bundles.

(6) The method for producing a reinforcing fiber base material according to (4) or (5), wherein the softening temperature of the binder resin is 50 ° C. or more lower than the softening temperature of the network resin material sheet. do.

According to the method for producing a reinforcing fiber base material according to (6), the shape of the mesh-like resin material sheet is easily maintained even after the bonding step, so that the mesh-like resin material sheet is connected in the plane direction. As a result, the morphological stability of the reinforcing fiber base material is improved. In addition, it is possible to improve the handleability during the transport process in which the reinforcing fiber base material is transported during the production of the reinforcing fiber preform.

(7) The mesh-like resin material sheet according to any one of (1) to (6), wherein the basis weight of the reinforcing fiber bundle layer is 100 parts by weight. A method for producing a reinforcing fiber base material, which has a basis weight of 1 to 550 parts by weight.

According to the method for producing a reinforcing fiber base material according to (7), at least one of an injection molding method and a press molding method can be applied to the laminated reinforcing fiber base material.

(8) A method for producing a reinforcing fiber preform using a reinforcing fiber base material produced by the method for producing a reinforcing fiber base material according to any one of (1) to (7), wherein the reinforcing fiber base material is used. A transport step of transporting the laminated fiber base material from the table using a transport means, a laminating step of laminating the transported reinforcing fiber base material, and a preform treatment for shaping the laminated reinforcing fiber base material into the shape of a molded body. A method for producing a reinforcing fiber preform, which comprises a shaping process.

According to the method for producing a reinforcing fiber preform according to (8), the impregnation property in the resin injection step of injecting the matrix resin is good, and the mechanical properties such as impact resistance, particularly the compressive strength after impact is applied. A reinforcing fiber preform having excellent CAI can be obtained.

(9) A method for producing a fiber-reinforced composite material molded product using a reinforcing fiber preform produced by the method for producing a reinforcing fiber preform according to (8), wherein the reinforcing fiber preform is impregnated with a matrix resin. A method for producing a fiber-reinforced composite material molded body, which comprises a resin impregnation step.

According to the method for producing a fiber-reinforced composite material molded body according to (9), a fiber-reinforced composite material molded body having excellent mechanical properties and being lightweight can be obtained.

According to the present invention, a reinforcing fiber base material and a reinforcing fiber preform having excellent morphological stability, shapeability, and resin impregnation property as well as excellent yield of the reinforcing fiber bundle can be obtained, and impact resistance after molding can be obtained. A fiber-reinforced composite material molded body (FRP molded body) having excellent properties can be obtained.

It is a schematic perspective view which shows typically the reinforcing fiber base material manufactured by the manufacturing method of the reinforcing fiber base material as one Embodiment of this invention. It is explanatory drawing explaining an example of the mesh-like resin material sheet arrangement process in this embodiment. It is explanatory drawing explaining an example of the reinforcing fiber bundle layer forming process in this embodiment. It is explanatory drawing explaining an example of the bonding process in this embodiment. It is explanatory drawing explaining an example of the transfer process in this embodiment. It is explanatory drawing explaining an example of the preform shaping process in this embodiment.

Hereinafter, examples of embodiments of the present invention will be described with reference to the drawings. First, the reinforcing fiber base material 1 manufactured or used for manufacturing in the present embodiment will be described.

A. Reinforced fiber base material:
FIG. 1 is a schematic perspective view schematically showing a reinforcing fiber base material 1 manufactured by a method for producing a reinforcing fiber base material as an embodiment of the present invention. The reinforcing fiber base material 1 is formed by adhering and integrating the reinforcing fiber bundles 11 on one side of the mesh-like resin material sheet 10 after the reinforcing fiber bundles 11 are aligned and placed.

The reinforcing fiber base material 1 has a mesh-like resin material sheet 10 on at least one surface of a reinforcing fiber bundle layer formed by aligning a plurality of reinforcing fiber bundles 11. By allowing the mesh-like resin material sheet 10 to exist on at least one surface of the reinforcing fiber bundle layer, morphological stability such as the position and fiber orientation of the reinforcing fiber bundle 11 in the reinforcing fiber bundle layer placed in a planar shape is improved. At the same time, it is possible to improve the handleability of the reinforcing fiber base material 1 during transportation.

In the present embodiment, the mesh shape means a shape having holes in the thickness direction on a plane. In other words, the mesh shape is a shape in which a resin material is present in a portion corresponding to the mesh of the mesh and holes are formed in the gap portion of the mesh. With such a form, a matrix resin or an air flow path can be secured in the thickness direction of the reinforcing fiber base material 1. Examples of the mesh-like resin material sheet 10 include non-woven fabric, matte, net, mesh, woven fabric, knitted fabric, short fiber group, perforated film, and porous film. Among them, the non-woven fabric, the mat or the mesh is preferable because it can be obtained at a low price and the matrix resin and the air flow path are formed in the plane direction, so that the effect of securing the matrix resin and the air flow path is high.

The mesh-like resin material sheet 10 in the present embodiment includes a polyamide resin, a polyester resin, a polyphenylene sulfide resin, a polyetherimide resin, a polyether sulfone resin, a polyvinyl formal resin, a polyether ether ketone resin, a polycarbonate resin, a polyether sulfone resin, and a polyphenylene. It is composed of a thermoplastic resin material composed of at least one selected from ether resin, polyimide resin, polyamideimide resin and phenoxy resin, or a mixture thereof. Further, the network resin material sheet 10 in the present embodiment may be composed of a mixture of the above-mentioned thermoplastic resin material and a thermosetting resin material selected from unsaturated polyester, vinyl ester, epoxy and phenol. In the preform shaping step in the method for producing a reinforcing fiber preform, which will be described later, an FRP molded product produced by using the reinforcing fiber base material 1 by arranging the mesh-like resin material sheet 10 between the reinforcing fiber bundle layers. Excellent mechanical properties can be achieved. Such an FRP molded product is particularly excellent in CAI, which is the compressive strength after impact is applied.

The reinforcing fiber bundle 11 used in the present embodiment is a multifilament yarn, such as a glass fiber yarn, an organic fiber yarn, and a carbon fiber yarn. The organic fibers in the organic fiber yarn are aramid, PBO, PVA, PE and the like. The carbon fibers in the carbon fiber yarn are PAN-based, pitch-based, and the like. Carbon fiber has excellent specific strength and specific elastic modulus, and hardly absorbs water. Therefore, carbon fiber is preferably used as a reinforcing fiber for aircraft structural materials and automobiles. The number of filaments of the reinforcing fiber bundle used in this embodiment is preferably in the range of 3,000 to 50,000 filaments. The number of filaments of the reinforcing fiber bundle 11 used in the present embodiment is particularly preferably in the range of 12,000 to 24,000 filaments from the viewpoint of handleability. The form of the reinforcing fiber bundle 11 is not particularly limited, but it is preferably a non-twisted yarn having excellent stability in width and thickness. The form of the reinforcing fiber bundle 11 is preferably an open fiber yarn having a further excellent fiber orientation.

Further, it is preferable that the binder resin is attached to the surface of the reinforcing fiber bundle 11 in the present embodiment. Since the binder resin is attached to the reinforcing fiber bundle 11, the reinforcing fiber bundle 11 is provided with morphological stability, so that the reinforcing fiber bundle 11 having excellent width stability can be obtained. In the present embodiment, the reinforcing fiber bundle 11 is aligned and placed from the reinforcing fiber bundle mounting head in the reinforcing fiber bundle layer forming step, but if the width stability of the reinforcing fiber bundle 11 is not good, the reinforcing fiber bundles 11 are adjacent to each other. The fiber bundles 11 may have gaps or overlaps with each other, which may induce unevenness in the basis weight and thickness of the reinforcing fiber base material 1. The binder resin may be any of the thermoplastic resin material, the thermosetting resin material, or a mixture thereof exemplified as the constitution of the mesh-like resin material sheet 10 described above. Further, the binder resin is preferably adhered in a dot shape, a linear shape, a mesh shape, or the like from the viewpoint of the flexibility of the reinforcing fiber bundle 11 and the impregnation property in the resin injection step. The amount of the binder resin attached is preferably such that the basis weight of the binder resin is in the range of 1 to 20 parts by weight when the basis weight of the reinforcing fiber bundle 11 is 100 parts by weight. The amount of the binder resin adhered is more preferably an amount in which the basis weight of the binder resin is in the range of 2 to 18 parts by weight, and further 3 to 16 parts by weight, when the basis weight of the reinforcing fiber bundle 11 is 100 parts by weight. The amount is preferably within the range of. If the basis weight of the binder resin is less than 1 part by weight, not only the width stability effect is difficult to obtain, but also the adhesiveness to the mesh-like resin material sheet 10 cannot be sufficiently obtained, and the morphological stability of the reinforcing fiber base material 1 is obtained. Is not preferable because it reduces. Further, if the basis weight of the binder resin exceeds 20 parts by weight, the flexibility of the reinforcing fiber bundle 11 and the impregnation property in the resin injection step may decrease, which is not preferable. When the flexibility of the reinforcing fiber bundle 11 decreases, when the reinforcing fiber bundle 11 wound around the bobbin is pulled out and placed in the reinforcing fiber bundle layer forming step, the end portion of the placed reinforcing fiber bundle 11 becomes curly. This may cause a problem of floating up, or may reduce the shapeability in the preform shaping process.

B. Manufacturing method of reinforcing fiber base material:
Next, the method for producing the reinforcing fiber base material 1 in the present embodiment will be described. The method for producing the reinforcing fiber base material 1 in the present embodiment includes a mesh-like resin material sheet arranging step, a reinforcing fiber bundle layer forming step, and an bonding step.

B1. Reticulated resin material sheet placement process:
FIG. 2 is an explanatory diagram illustrating an example of a mesh-like resin material sheet arranging process in the present embodiment. In the mesh-like resin material sheet arranging step, the mesh-like resin material sheet 10 is arranged on a table 100 having a temporary fixing means (not shown).

In the present embodiment, a device that performs electrostatic adsorption or adsorption by air suction can be used as the temporary fixing means. The objects to be temporarily fixed are the mesh-like resin material sheet 10 and the reinforcing fiber bundle 11. When the mesh-like resin material sheet 10 is arranged on the table 100 having such a temporary fixing means, the adsorption force due to static electricity or air suction permeates the mesh-like resin material sheet 10, so that it is placed in the subsequent reinforcing fiber bundle layer forming step. It is possible to temporarily fix the reinforcing fiber bundles 11 at the same time. Since the reinforcing fiber bundle 11 can be temporarily fixed by the temporary fixing means, even a reinforcing fiber bundle having no tackiness at room temperature can be placed with high accuracy without causing the end portion to be lifted or the fiber orientation to be misaligned.

The shape of the mesh-like resin material sheet 10 to be arranged may be larger than the area of the reinforcing fiber bundle layer formed by aligning the reinforcing fiber bundles 11 formed in the subsequent reinforcing fiber bundle layer forming step, or the reinforcing fiber bundle 11 may be formed. The mesh-like resin material sheet 10 smaller than the area of the reinforcing fiber bundle layer formed by aligning the two may be selectively arranged only in a necessary portion. Further, in order to improve the shapeability in the preform shaping step in the method for producing the reinforcing fiber preform described later, the mesh-like resin material sheet 10 may have a notch. In this case, it is preferable to have a notch extending in a direction intersecting the fiber direction of the reinforcing fiber bundle 11 as a notch that does not easily affect the orientation of the reinforcing fiber bundle 11.

B2. Reinforcing fiber bundle layer forming process:
FIG. 3 is an explanatory diagram illustrating an example of the reinforcing fiber bundle layer forming step in the present embodiment. In the reinforcing fiber bundle layer forming step, the reinforcing fiber bundle 11 is aligned and placed on the mesh-like resin material sheet 10 by the reinforcing fiber bundle mounting head 110. The reinforcing fiber bundle mounting head 110 in the present embodiment is mounted on a robot arm or a gantry (not shown) and is a part of a so-called automatic laminating device. By using such a device, the reinforcing fiber bundle 11 can be aligned and placed only in a necessary portion. Therefore, as compared with the method of cutting out a desired shape from a sheet-shaped reinforcing fiber base material and laminating it manually, it is possible to obtain effects such as improvement of the yield of the reinforcing fiber bundle 11 and labor saving in the process. can.

The bobbin 111 supplies the reinforcing fiber bundle 11. In this embodiment, the bobbin 111 is built in the reinforcing fiber bundle mounting head 110. In another embodiment, the bobbin 111 may be supplied from a creel station (not shown) installed at a location distant from the reinforcing fiber bundle mounting head 110. Further, in the present embodiment, a plurality of reinforcing fiber bundles 11 are drawn out at the same time from the viewpoint of improving the efficiency of the reinforcing fiber bundle layer forming step, but in other embodiments, the reinforcing fiber bundles 11 are drawn out one by one. Is also good.

In the reinforcing fiber bundle layer forming step, first, the reinforcing fiber bundle mounting head 110 moves to the point A1 on the mesh-like resin material sheet 10 arranged on the table 100, and the end portion of the reinforcing fiber bundle 11 is pressed against the point A1. Temporary fixing is performed by the reinforcing fiber bundle mounting head 110 approaching the point A1. Then, after moving to the point B1 while feeding out the reinforcing fiber bundle 11 according to the moving speed of the reinforcing fiber bundle mounting head 110, the reinforcing fiber bundle 11 is cut by a cutting mechanism (not shown) to form a mesh-like resin material. A reinforcing fiber bundle 11 having a predetermined length is placed on the sheet 10. The reinforcing fiber bundle 11 placed in this way is in a state of being temporarily fixed on the mesh-like resin material sheet 10 by the temporary fixing means from the point A1 to the point B1. Next, the reinforcing fiber bundle mounting head 110 is moved to the point A2, and the reinforcing fiber bundle 11 is newly mounted so as to be adjacent to the previously mounted reinforcing fiber bundle 11 and the reinforcing fiber bundles 11 are parallel to each other. The reinforcing fiber bundle 11 is placed and temporarily fixed on the mesh-like resin material sheet 10. By repeating this operation, a reinforcing fiber bundle layer is formed.

When the reinforcing fiber bundle 11 is placed, the reinforcing fiber bundle 11 is not too far from the already placed reinforcing fiber bundle 11 and the reinforcing fiber bundles 11 are not overlapped with each other. Is preferably placed. If the reinforcing fiber bundles 11 are overlapped or separated too much, the desired material properties cannot be obtained when the FRP molded body is processed, and the surface of the reinforcing fiber base material 1 is uneven, so that dimensional accuracy can be obtained. There is no fear. Therefore, the placement interval between the reinforcing fiber bundles 11 is preferably 0 to 2 mm. Further, even if the reinforcing fiber bundles 11 do not overlap each other, if the placement intervals between the reinforcing fiber bundles 11 are too narrow, the resin impregnation property in the resin injection step of injecting the matrix resin may not be sufficient. Therefore, the placement interval between the reinforcing fiber bundles 11 is more preferably 0.5 to 2 mm.

As a method of mounting while controlling the mounting interval between the reinforcing fiber bundles 11, there is a method of controlling the moving position of the reinforcing fiber bundle mounting head 110 based on the position data input in advance. According to this method, it is necessary to input the coordinates of the start point and the end point on which the reinforcing fiber bundle 11 is placed in a computer or the like in advance before performing the reinforcing fiber bundle layer forming step. Therefore, when the number of types of desired shapes of the reinforcing fiber base material 1 increases, the amount of work for inputting coordinates becomes very large. On the other hand, in the present embodiment, by detecting the color tone difference (contrast) between the mesh-like resin material sheet 10 and the table 100, the start point and the end point on which the reinforcing fiber bundle 11 is placed in the mesh-like resin material sheet 10 are automatically set. It is possible to detect with. In other words, the positions where the contrast is detected are detected as the start point and the end point, and the reinforcing fiber bundle 11 is placed based on the start point and the end point. For example, when the reinforcing fiber bundle 11 is linearly placed on the mesh-like resin material sheet 10, the reinforcing fiber bundle 11 is started from the position of the starting point where the contrast is detected, and the contrast is detected. By cutting the reinforcing fiber bundle 11 at the position of the end point, the reinforcing fiber bundle 11 is placed. That is, if the mesh-like resin material sheet 10 is cut into a desired shape in advance, the placement interval corresponding to the width of the reinforcing fiber bundle 11 can be specified, and the shape can be of any shape without inputting the coordinates. It becomes possible to prepare the reinforcing fiber base material 1. Further, if the contrast between the reinforcing fiber bundle 11 placed immediately before and the mesh-like resin material sheet 10 is detected, it is possible to omit the input of the placement interval.

The basis weight per reinforcing fiber bundle layer in the reinforcing fiber base material 1 of the present embodiment is preferably in the range of ^{50 to 800 g / m 2.} The basis weight per reinforcing fiber bundle layer is more preferably in the range of ^{100 to 500 g / m 2} , and even more preferably in the range of 120 to 300 g / m ^2. The basis weight per reinforcing fiber bundle layer can be calculated from the basis weight (g / m) of the reinforcing fiber bundle and the placement interval of the reinforcing fiber bundle 11 in the reinforcing fiber bundle layer forming step. If the basis weight of the reinforcing fiber bundle layer ^{is less than 50 g / m 2} , the number of laminated layers for obtaining a predetermined thickness of the FRP molded body increases, which is not preferable because the workability of molding is poor. Further, if the basis weight of the reinforcing fiber bundle layer is small, a gap is likely to be formed between the reinforcing fiber bundles 11 in the reinforcing fiber bundle layer, so that the reinforcing fiber volume fraction Vf tends to be partially non-uniform. Therefore, when molded, the thickness of the FRP molded body becomes thicker where the reinforcing fiber volume fraction Vf is large, and the thickness of the FRP molded body becomes thinner where the reinforcing fiber volume fraction Vf is small. That is, the surface of the FRP molded product tends to have an uneven shape. In such a case, if the reinforcing fiber bundle 11 is thinly expanded by a vibrating roller or air jet injection at the stage of preparing the reinforcing fiber bundle 11, the reinforcing fiber volume fraction Vf is increased over the entire surface of the reinforcing fiber base material 1. Since it becomes uniform, an FRP molded body having a smooth surface can be obtained, which is preferable. Further, if the basis weight per layer of the reinforcing fiber bundle layer ^{exceeds 800 g / m 2} , the impregnation property of the matrix resin with respect to the reinforcing fiber base material 1 is deteriorated in the resin injection step of injecting the matrix resin, which is not preferable.

B3. Adhesion process:
FIG. 4 is an explanatory diagram illustrating an example of the bonding process in the present embodiment. In the bonding step of the present embodiment, the mesh-like resin material sheet 10 and the reinforcing fiber bundle 11 are bonded using the indenter 120. The bonding step may be performed on the entire surface of the reinforcing fiber bundle layer formed by aligning the reinforcing fiber bundles 11, or only a necessary portion smaller than the area of the reinforcing fiber bundle layer formed by aligning the reinforcing fiber bundles 11 is selected. It may be adhered to the target. When the entire surface of the reinforcing fiber bundle layer is adhered to the mesh-like resin material sheet 10, the morphological stability of the reinforcing fiber base material 1 is excellent. On the other hand, when the reinforcing fiber bundle layer is partially adhered to the mesh-like resin material sheet 10, when shaping the shape of the molded product in the preform shaping step of the method for manufacturing the reinforcing fiber preform described later. Easy to deform (that is, good formability). Therefore, it is preferable to use these arbitrarily depending on the complexity of the shape of the molded product.

In the present embodiment, the adhesion is performed by heat fusion with the indenter 120, but instead of the indenter 120, heat fusion may be performed using a thermal roller (not shown) or an infrared heater (not shown). .. Further, instead of heat fusion, stitching may be used for bonding.

When the reinforcing fiber bundle 11 to which the binder resin is not attached is used, the heating temperature used in the bonding step ranges from the softening temperature of the mesh-like resin material sheet 10 to a temperature 30 ° C. higher than the softening temperature of the mesh-like resin material sheet 10. It is desirable to be inside.

On the other hand, when the reinforcing fiber bundle 11 to which the binder resin is attached is used, it is desirable that the temperature is within the range of 30 ° C. higher than the softening temperature of the binder resin from the softening temperature of the binder resin. When the heating temperature used in the bonding step is low, the binder resin may not be sufficiently softened and the reinforcing fiber bundle 11 and the mesh-like resin material sheet 10 may not be bonded. Further, when the heating temperature used in the bonding step is high, the binder resin may permeate into the reinforcing fiber bundle 11 and the impregnation property of the matrix resin may deteriorate.

Here, in the present embodiment, the softening temperature refers to the melting point when the binder resin or the mesh-like resin material sheet is a crystalline resin material, and the glass transition point when the binder resin or the mesh-like resin material sheet is an amorphous resin material, and is a differential scanning calorimeter. (DSC) refers to a value measured at a heating rate of 10 ° C./min according to JIS K7121 (1987).

When the binder resin has a softening temperature lower than that of the mesh-like resin material sheet 10, the shape of the mesh-like resin material sheet 10 is maintained even after heat fusion, so that the plane direction of the mesh-like resin material sheet 10 By the connection of the above, it is possible to improve the morphological stability of the reinforcing fiber base material 1 and improve the handleability during transportation and the like. In addition, in the resin injection step of injecting the matrix resin, the mesh-like resin material sheet 10 whose shape is maintained serves as a spacer for securing a space, and the flow path of the matrix resin is formed between the layers of the reinforcing fiber bundle layer. Secure. By securing the flow path of the matrix resin by the mesh-like resin material sheet 10, not only the impregnation of the matrix resin becomes easy, but also the impregnation speed thereof becomes high, so that the productivity of the FRP molded product is improved. The effect is also realized. In order to efficiently realize such an effect, the softening temperature of the binder resin is preferably 50 ° C. or more lower than the softening temperature of the mesh-like resin material sheet 10.

When the bonding means is a stitch, the sewing structure includes, for example, single-ring sewing and 1/1 tricot knitting. The material of the stitch thread can be selected from polyester resin, polyamide resin, polyethylene resin, vinyl alcohol resin, polyphenylene sulfide resin, polyaramid resin, and compositions thereof. Among the listed stitch thread materials, polyester resin and polyamide resin are preferable. From the viewpoint of the shapeability of the reinforcing fiber base material 1, the material of the stitch yarn is preferably a processed yarn of spandex (polyurethane elastic fiber), polyamide resin or polyester resin. The fineness of the stitch thread is preferably 1/5 or less of the reinforcing fiber bundle 11 in order to suppress the crimp of the reinforcing fiber bundle. Further, from the viewpoint of morphological stability and production stability of the reinforcing fiber base material 1, the fineness of the stitch thread is preferably 10 dtex or more, more preferably 30 dtex or more. Further, from the viewpoint of shapeability in the preform shaping step, the stitch thread preferably has elasticity.

The flow of the steps described so far is in the order of "reinforcing fiber bundle layer forming process-> reinforcing fiber bundle layer forming process-> bonding process", but "reinforcing fiber bundle layer forming process-> mesh-like resin material placement process-> bonding process". It is possible to obtain the same effect as the above-mentioned contents by setting the order of "."

The basis weight of the mesh-like resin material sheet 10 in the present embodiment is 1 to 550 parts by weight when the basis weight of the reinforcing fiber bundle layer is 100 parts by weight. For this purpose, in the method for producing an FRP molded product using the reinforcing fiber base material 1, a resin injection step of injecting a liquid matrix resin in the resin impregnation step after laminating the reinforcing fiber base material 1 of the present embodiment. This means that it can be applied to both the "injection molding method" in which the reinforcing fiber base material 1 of the present embodiment is laminated and then hot-pressed. In the "press molding method", the mesh-like resin material sheet 10 itself is impregnated as a matrix resin by a press machine or the like having a heating function.

When the "injection molding method" is performed, the basis weight of the mesh-like resin material sheet 10 in the present embodiment is preferably 1 to 20 parts by weight when the basis weight of the reinforcing fiber bundle layer is 100 parts by weight. The basis weight of the mesh-like resin material sheet 10 is more preferably 2 to 18 parts by weight, still more preferably 3 to 16 parts by weight, when the basis weight of the reinforcing fiber bundle layer is 100 parts by weight. If the basis weight of the mesh-like resin material sheet 10 is less than 1 part by weight, not only the handleability of the reinforcing fiber base material 1 is deteriorated, but also the mechanical properties due to the presence of the mesh-like resin material sheet 10 between the reinforcing fiber bundle layers. This is not preferable because the effect of improving the above is small. Further, when the mesh size of the mesh-like resin material sheet 10 exceeds 20 parts by weight, the volume content of the reinforcing fibers in the FRP molded product becomes too low when the FRP molded product is formed, or the heat resistance and chemical resistance of the FRP molded product are high. It is not preferable because the properties and compressive strength may decrease.

When the "press molding method" is performed, the basis weight of the mesh-like resin material sheet 10 in the present embodiment is preferably 10 to 550 parts by weight when the basis weight of the reinforcing fiber bundle layer is 100 parts by weight. The basis weight of the mesh-like resin material sheet 10 is more preferably 30 to 350 parts by weight, still more preferably 40 to 300 parts by weight, when the basis weight of the reinforcing fiber bundle layer is 100 parts by weight. If the basis weight of the mesh-like resin material sheet 10 is less than 10 parts by weight, the proportion of the reinforcing fiber bundle 11 in the reinforcing fiber base material 1 becomes high, and it becomes difficult to impregnate the matrix resin, which is not preferable. Further, if the basis weight of the mesh-like resin material sheet 10 exceeds 550 parts by weight, the proportion of the reinforcing fiber bundle 11 in the reinforcing fiber base material 1 becomes low, and the matrix resin may flow out during press molding, which is not preferable.

According to the method for producing the reinforcing fiber base material 1 described above, not only the yield of the reinforcing fiber bundle 11 is excellent, but also the handleability during transportation (particularly, the morphological stability of the reinforcing fiber base material) and the preform shaping are performed. A reinforcing fiber base material 1 having excellent shapeability in the process is produced.

C. Manufacturing method of reinforcing fiber preform:
Next, a method for producing a reinforcing fiber preform using the reinforcing fiber base material 1 will be described. The method for producing a reinforcing fiber preform in the present embodiment includes a transporting step, a laminating step, and a preform shaping step.

C1. Transport process:
FIG. 5 is an explanatory diagram illustrating an example of a transfer process in the present embodiment. As shown in FIG. 5, in the transfer step, the reinforcing fiber base material 1 is conveyed from the table 100 to a predetermined position on another table 210 by using a transfer means such as a robot hand 200 (transfer step). The method for holding the reinforcing fiber base material 1 is not particularly limited, and a method such as electrostatic adsorption or air suction can be used in addition to a method such as a clamp or a needle. As described above, since the reinforcing fiber base material 1 produced by the method according to the present embodiment is adhered to the mesh-like resin material sheet 10, the shape of the reinforcing fiber base material 1 is less likely to collapse in the transport process. As a method for holding the reinforcing fiber base material 1, methods such as electrostatic adsorption and air suction attract the reinforcing fiber base material 1 on a surface, so that the reinforcing fiber base material 1 is compared with a method such as a clamp or a needle. It is preferable because it does not easily lose its shape.

C2. Laminating process and preform shaping process:
By repeating the above transfer process, the reinforcing fiber base material 1 is laminated (lamination step) to prepare a reinforcing fiber base material laminated body in which the reinforcing fiber base material 1 is laminated, and then the molded body is shaped and heated. (Preform shaping step) is performed to prepare a reinforcing fiber base material preform. In the preform shaping step, a method such as a pressure shaping using a rubber can be used in addition to the press shaping by the upper and lower molds.

In the case of press shaping (not shown) by the upper and lower molds, the table 210 is a lower mold having the shape of a molded body. The paired upper mold may be a split shape that can be operated independently in order to improve the followability to a fine uneven shape.

FIG. 6 is an explanatory diagram illustrating an example of the preform shaping step in the present embodiment. As the preform shaping step, the reduced pressure shaping using the rubber used in the present embodiment will be described with reference to FIG. A mold 220 and a sealing material 240 in the shape of a molded body are provided on the table 210. Next, the reinforcing fiber base material 1 is repeatedly laminated on the mold 220 to prepare the reinforcing fiber base material laminate 2. The produced reinforcing fiber base material laminate 2 and the mold 220 are covered with the rubber 230, and the rubber 230 is brought into close contact with the table 210 with the sealing material 240 to form a closed space surrounded by the table 210 and the rubber 230. The closed space contracts by discharging the air in the closed space from the suction port 250 provided on the table 210. As the closed space shrinks, the rubber 230 presses the reinforcing fiber base material laminate 2 against the mold 220. The reinforcing fiber base material laminate 2 pressed against the mold 220 is shaped into the shape of the molded body.

In such a preform shaping step, all the number of laminated reinforcing fiber base materials 1 required for the target molded product may be performed at once, or may be performed in several steps.

The heating temperature used in the preform shaping step is the softening temperature of the mesh-like resin material sheet 10 from the softening temperature of the mesh-like resin material sheet 10 when a fiber bundle to which the binder resin is not attached is used as the reinforcing fiber bundle 11. It is desirable that the temperature is within the range of 30 ° C. higher. The heating temperature in the preform shaping step is within the range of 30 ° C. higher than the softening temperature of the binder resin from the softening temperature of the binder resin when the fiber bundle to which the binder resin is attached is used as the reinforcing fiber bundle 11. Is desirable. If the heating temperature used in the preform shaping step is low, the mesh-like resin material sheet 10 or the binder resin may not be sufficiently softened and the preform may not be fixed in shape. Further, if the heating temperature used in the preform shaping step is high, the mesh-like resin material sheet 10 or the binder resin may permeate into the reinforcing fiber bundle 11, and the impregnation property of the matrix resin in the injection molding method may deteriorate. Similar to the above, when the fiber bundle to which the binder resin is attached is used as the reinforcing fiber bundle 11, the mesh-like resin material sheet 10 serves as a spacer for securing a space in the resin injection step, and is used between the layers of the reinforcing fiber bundle layer. Secure a flow path for the matrix resin. By securing the flow path of the matrix resin by the mesh-like resin material sheet 10, not only the impregnation of the matrix resin becomes easy, but also the impregnation speed thereof becomes high, so that the productivity of the FRP molded product is improved. It also realizes such effects.

According to the method for producing a reinforcing fiber preform described above, a reinforcing fiber preform having good impregnation property in the resin injection step of injecting a matrix resin and excellent mechanical properties such as impact resistance can be obtained. Such a reinforcing fiber preform is particularly excellent in CAI, which is the compressive strength after impact is applied.

D. Method for manufacturing fiber-reinforced composite molded article:
Subsequently, a method for producing a fiber-reinforced composite material molded body (FRP molded body) using a reinforcing fiber preform will be described. The method for producing a fiber-reinforced composite material molded product in the present embodiment includes a resin impregnation step.

D1. Resin impregnation process:
As the method for producing the FRP molded product according to the present embodiment, the "injection molding method" and the "press molding method" can be adopted as the resin impregnation step as described above.

As the "injection molding method", RTM (Resin Transfer Molding) molding and VaRTM (Vacum assisted Resin Transfer Molding) molding are preferably applied. The mesh-like resin material sheet 10 adhered to the reinforcing fiber base material 1 of the present embodiment functions as a flow path (air path) when the air inside the reinforcing fiber base material 1 is discharged, and is a medium for diffusing the matrix resin. Demonstrate the function as. Therefore, it is possible to improve the internal quality of the FRP molded product and speed up the resin injection process. Further, since the mesh-like resin material sheet 10 constituting the reinforcing fiber base material 1 of the present embodiment retains its shape even after the bonding step, that is, after heat fusion, it is connected in the plane direction, so that the pressure is high. It is possible to prevent deformation of the reinforcing fiber base material when the matrix resin is injected. Such an injection molding method is excellent in the productivity of the FRP molded product, but the applied matrix resin needs to have a low viscosity. For this reason, in the past, there were cases where the mechanical properties could not be fully exhibited. However, in the FRP molded product manufactured by the method for producing the FRP molded product of the present embodiment, since the mesh-like resin material sheet 10 is arranged between the layers composed of the reinforcing fiber bundles 11, after the resin injection step. Excellent mechanical properties can be achieved in the FRP molded product of. Such an FRP molded product is particularly excellent in CAI, which is the compressive strength after impact is applied.

The matrix resin used is solidified as needed. Solidification means curing or polymerization. Preferred examples of such a matrix resin include a thermosetting resin, a thermoplastic resin for RIM (Reaction Injection Molding), and the like. Among the matrix resins listed, at least one selected from epoxy resins, phenol resins, vinyl ester resins, unsaturated polyester resins, cyanate ester resins, bismaleimide resins and benzoxazine resins suitable for injection molding methods is used. preferable.

In the "press molding method", the mesh-like resin material sheet 10 itself becomes the matrix resin. For impregnation of the matrix resin, a press machine or the like having a heating function can be used.

The FRP molded product produced by the method according to this embodiment has excellent mechanical properties and is lightweight. Therefore, the FRP molded product manufactured by the method according to the present embodiment is used for a primary structural member, a secondary structural member, an exterior member, or an interior member in any of transportation equipment of an aircraft, an automobile, or a ship. Is preferable.

1 ... Reinforcing fiber base material 2 ... Reinforcing fiber base material laminate 10 ... Reinforcing fiber base material sheet 11 ... Reinforcing fiber bundle 100 ... Table 110 ... Reinforcing fiber bundle mounting head 111 ... Bobbin 120 ... Indenter 210 ... Table 220 ... Type 230 ... Rubber 240 ... Sealing material 250 ... Suction port

Claims (9)

A method for manufacturing a reinforcing fiber base material.
On a table having temporary fixing means, polyamide resin, polyester resin, polyphenylene sulfide resin, polyetherimide resin, polyether sulfone resin, polyvinyl formal resin, polyether ether ketone resin, polycarbonate resin, polysulfone resin, polyphenylene ether resin, A mesh-like resin material sheet arranging step for arranging a network-like resin material sheet composed of at least one selected from a polyimide resin, a polyamideimide resin and a phenoxy resin, or a mixture thereof.
A reinforcing fiber bundle layer forming step of repeating the process of repeatedly placing at least one reinforcing fiber bundle on the mesh-like resin material sheet by aligning it from the reinforcing fiber bundle mounting head.
A method for producing a reinforcing fiber base material, comprising an adhesive step of at least partially adhering the mesh-like resin material sheet and the reinforcing fiber bundle. A method for manufacturing a reinforcing fiber base material.
A reinforcing fiber bundle layer forming step in which at least one reinforcing fiber bundle is repeatedly aligned and placed from the reinforcing fiber bundle mounting head on a table having a temporary fixing means, and a step of forming the reinforcing fiber bundle layer.
On the reinforcing fiber bundle, polyamide resin, polyester resin, polyphenylene sulfide resin, polyetherimide resin, polyether sulfone resin, polyvinylformal resin, polyether ether ketone resin, polycarbonate resin, polysulfone resin, polyphenylene ether resin, polyimide A mesh-like resin material sheet arranging step of arranging a network-like resin material sheet composed of at least one selected from a resin, a polyamideimide resin and a phenoxy resin, or a mixture thereof, and
A bonding step of at least partially adhering the mesh-like resin material sheet and the reinforcing fiber bundle is provided .
A method for producing a reinforcing fiber base material, wherein in the reinforcing fiber bundle layer forming step, the placement interval between the reinforcing fiber bundles is larger than 0 mm (millimeter) and 2 mm or less. The method for producing a reinforcing fiber base material according to claim 1.
In the reinforcing fiber bundle layer forming step, the color tone difference between the table and the mesh-like resin material sheet is detected, and the position where the color tone difference is detected is set as a start point and an end point on which the reinforcing fiber bundle is placed. A method for producing a reinforcing fiber base material on which a bundle is placed. The method for producing a reinforcing fiber base material according to any one of claims 1 to 3.
A method for producing a reinforcing fiber base material, which comprises adhering a binder resin to the surface of the reinforcing fiber bundle. The method for producing a reinforcing fiber base material according to claim 4.
A method for producing a reinforcing fiber base material, wherein the binder resin has a basis weight of 1 to 20 parts by weight when the basis weight of the reinforcing fiber bundle is 100 parts by weight. The method for producing a reinforcing fiber base material according to claim 4 or 5.
A method for producing a reinforcing fiber base material, wherein the softening temperature of the binder resin is 50 ° C. or more lower than the softening temperature of the mesh-like resin material sheet. The method for producing a reinforcing fiber base material according to any one of claims 1 to 6.
A method for producing a reinforcing fiber base material, characterized in that the basis weight of the mesh-like resin material sheet is 1 to 550 parts by weight when the basis weight of the reinforcing fiber bundle layer is 100 parts by weight. A method for producing a reinforcing fiber preform using a reinforcing fiber base material produced by the method for producing a reinforcing fiber base material according to any one of claims 1 to 7.
A transporting step of transporting the reinforcing fiber base material from the table using a transporting means,
Laminating process of laminating the conveyed reinforcing fiber base material, and
A method for producing a reinforcing fiber preform, comprising a preform shaping step of shaping the laminated reinforcing fiber base material into the shape of a molded body. A method for producing a fiber-reinforced composite material molded product using a reinforcing fiber preform produced by the method for producing a reinforcing fiber preform according to claim 8.
A method for producing a fiber-reinforced composite material molded body, comprising a resin impregnation step of impregnating the reinforcing fiber preform with a matrix resin.

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