Fiber-reinforced resin molded article and method for manufacturing a fiber-reinforced resin molded article

Abstract

The present invention provides a fiber-reinforced resin molded article having a surface with multiple high-strength protrusions and a surface with high adhesive strength to an adhesive. [Solution] The fiber-reinforced resin molded body (1) of the present invention integrally comprises a main body (10) including a matrix resin (18) and reinforcing fibers (17) contained within the matrix resin (18) and extending continuously in the longitudinal direction, and a plurality of protrusions (20) projecting from one side in the thickness direction of the main body (10), each having a certain cross-section and extending continuously in the longitudinal direction, and being arranged adjacent to each other in the width direction, and the surface area of ​​one side in the thickness direction of the fiber-reinforced resin molded body (1) is 110% or more and 200% or less of the area of ​​the reference plane (11), which is a virtual plane forming the boundary between the plurality of protrusions (20) and the main body (10).

Description

Technical Field

[0001] The present invention relates to a fiber-reinforced resin molded body containing reinforcing fibers and a matrix resin.

Background Art

[0002] A plate-like fiber-reinforced resin molded body containing reinforcing fibers and a matrix resin is known. The fiber-reinforced resin molded body is used, for example, as a reinforcing material for products such as vehicles, aircraft, ships, electronic devices, medical devices, civil engineering and construction materials, home appliances, tools, etc. Specifically, the adhesive surface of the fiber-reinforced resin molded body is adhered to the target surface of the product by an adhesive.

[0003] In the fiber-reinforced resin molded body as described above, when the adhesive surface was smooth, the fiber-reinforced resin molded body might peel off from the target surface of the product over time. That is, since the adhesive surface of the fiber-reinforced resin molded body was smooth, the contact area between the adhesive surface of the fiber-reinforced resin molded body and the adhesive was small, so the adhesive strength between the adhesive surface of the fiber-reinforced resin molded body and the adhesive was low.

[0004] On the other hand, if irregularities were formed on the adhesive surface, the adhesive strength could be increased. As such a fiber-reinforced resin molded body, the one disclosed in Patent Document 1 below is known. Specifically, Patent Document 1 discloses a drawn molded product in which a surface layer with irregularities formed on the surface of a molded product body made of a linear continuous fiber-reinforced thermosetting resin is formed. The surface layer contains a thermosetting resin and a plurality of fillers. There is also a method of forming irregularities on the surface of the fiber-reinforced resin molded body by rough machining by polishing.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the pultruded product described in Patent Document 1, an uneven surface is formed on the surface layer, increasing the contact area between the adhesive surface of the pultruded product and the adhesive. However, the surface layer does not contain reinforcing fibers, which may result in insufficient strength of the surface layer itself. Furthermore, in the case of roughening, there is a risk of reduced reinforcing effect due to the reinforcing fibers breaking midway or being exposed on the surface, and a decrease in adhesive strength due to the presence of polishing debris on the adhesive surface.

[0007] The present invention has been made in view of the above circumstances, and aims to provide a fiber-reinforced resin molded article having a surface with multiple protrusions that have high strength and a surface that has high adhesive strength with an adhesive, and a method for manufacturing a fiber-reinforced resin molded article. [Means for solving the problem]

[0008] To solve the above problems, a fiber-reinforced resin molded article according to one aspect of the present invention is a fiber-reinforced resin molded article that extends in the longitudinal direction and has constant dimensions in the width direction and thickness direction over the longitudinal direction, comprising: a main body portion including a matrix resin and reinforcing fibers contained in the matrix resin and extending continuously in the longitudinal direction; and a plurality of protrusions comprising a matrix resin and reinforcing fibers contained in the matrix resin and extending continuously in the longitudinal direction, projecting from one side of the main body portion in the thickness direction, wherein each of the plurality of protrusions extends continuously in the longitudinal direction with a constant cross-section and is arranged adjacent to each other in the width direction, and the surface area of ​​one side of the fiber-reinforced resin molded article in the thickness direction is 110% or more and 200% or less of the area of ​​a reference plane which is a virtual plane forming the boundary between the plurality of protrusions and the main body portion.

[0009] According to the present invention, the surface area on one side in the thickness direction of the fiber-reinforced resin molded article is 110% to 200% of the area of ​​the reference surface, so the contact area between the fiber-reinforced resin molded article and the adhesive is increased. As a result, the adhesive strength between the fiber-reinforced resin molded article and the adhesive is improved. Furthermore, since each of the multiple protrusions contains reinforcing fibers, a decrease in strength can be suppressed. Moreover, since the multiple protrusions extend along the longitudinal direction in which the reinforcing fibers extend, the reinforcing fibers are not cut compared to the case where the multiple protrusions do not extend in the longitudinal direction, so the generation of reinforcing fiber chips and the like on the surface of the fiber-reinforced resin molded article can be suppressed.

[0010] Preferably, the total fiber volume content, which is the volume ratio of the reinforcing fibers to the fiber-reinforced resin molded body, is 50% or more and 80% or less, and the difference obtained by subtracting the local fiber volume content, which is the volume ratio of the reinforcing fibers to the plurality of protrusions, from the total fiber volume content is less than 10%.

[0011] In this embodiment, since the difference obtained by subtracting the local fiber volume content from the total fiber volume content is less than 10%, a large amount of reinforcing fibers are present even in multiple protrusions, and the reinforcing effect of the reinforcing fibers can be fully exerted.

[0012] Preferably, each of the multiple protrusions has a slope that moves further away from the reference plane towards one or the other side in the width direction, and the angle between the slope and the reference plane is 30° or more and 60° or less.

[0013] If the angle between the slope and the reference plane is less than 30°, the adhesive strength between the fiber-reinforced resin molded body and the adhesive may decrease. On the other hand, if the angle between the slope and the reference plane exceeds 60°, the adhesive may not reach the other end (the far end) in the thickness direction of the slope, that is, the bottom of the valley formed between adjacent protrusions, when the adhesive is applied.

[0014] Preferably, the inclined surface has a first inclined surface that is further away from the reference surface as it moves toward one side in the width direction, and a second inclined surface that is further away from the reference surface as it moves toward the other side in the width direction, and the first inclined surface and the second inclined surface are arranged alternately along the width direction.

[0015] In this embodiment, since the first and second slopes are arranged alternately along the width direction, it is possible to further suppress the problem of the adhesive not reaching the other end (back side) of the slope (bottom of the valley) in the thickness direction of the slope when the adhesive is applied.

[0016] A method for manufacturing a fiber-reinforced resin molded article according to another aspect of the present invention includes the steps of: preparing a mold having a die hole inside which extends in the longitudinal direction and whose dimensions in the width and thickness directions are constant along the longitudinal direction; impregnating reinforcing fibers that extend continuously in the longitudinal direction with an uncured matrix resin to obtain a resin-impregnated fiber material; and heating the resin-impregnated fiber material while passing it through the die hole in the longitudinal direction to obtain a fiber-reinforced resin molded article including the matrix resin and the reinforcing fibers contained therein, wherein the die hole has a main body hole of a predetermined cross-section and a plurality of grooves formed on one side of the main body hole in the thickness direction, the plurality of grooves each have a constant cross-section and extend continuously in the longitudinal direction and are arranged adjacent to each other in the width direction, and the surface area of ​​one side of the die hole in the thickness direction is 110% or more and 200% or less of the area of ​​a reference plane which is a virtual plane forming the boundary between the plurality of grooves and the main body hole.

[0017] According to the present invention, since the surface area on one side in the thickness direction of the die hole is 110% or more and 200% or less of the area of ​​the reference surface, a fiber-reinforced resin molded article can be obtained in which the surface area on one side in the thickness direction of the fiber-reinforced resin molded article is 110% or more and 200% or less of the size of the reference surface. [Effects of the Invention]

[0018] As described above, according to the present invention, it is possible to provide a fiber-reinforced resin molded body having a surface with a plurality of convex portions having high strength and a high adhesive strength with an adhesive, and a method for manufacturing the fiber-reinforced resin molded body.

Brief Description of Drawings

[0019] [Figure 1] It is a perspective view showing a fiber-reinforced resin molded body according to an embodiment of the present invention. [Figure 2] It is an enlarged cross-sectional view showing a part of the fiber-reinforced resin molded body according to this embodiment. [Figure 3] It is a microscopic photograph of the convex portion of the fiber-reinforced resin molded body according to this embodiment. [Figure 4] It is a cross-sectional view schematically showing a manufacturing apparatus for manufacturing the above fiber-reinforced resin molded body. [Figure 5] It is a perspective view showing a mold according to this embodiment. [Figure 6] It is a flowchart summarizing the manufacturing procedure of the fiber-reinforced resin molded body by the above manufacturing apparatus. [Figure 7] It is an enlarged cross-sectional view showing a modified example of the fiber-reinforced resin molded body according to an embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0020] Hereinafter, preferred embodiments of the fiber-reinforced resin molded body and its manufacturing method of the present invention will be described while referring to the drawings. The fiber-reinforced resin molded body of the present invention is a molded product including continuous reinforcing fibers and a matrix resin including the continuous reinforcing fibers, and is molded by, for example, draw molding. The fiber-reinforced resin molded body can take various shapes, and can be, for example, plate-shaped.

[0021] [Structure of Fiber-Reinforced Resin Molded Body] Figure 1 is a perspective view showing a fiber-reinforced resin molded body 1 according to one embodiment of the present invention. Figure 2 is an enlarged cross-sectional view showing a part of the fiber-reinforced resin molded body 1 according to this embodiment. Figure 3 is a micrograph of a protrusion 20 of the fiber-reinforced resin molded body 1 according to this embodiment. In Figures 1 to 3, the directional relationships will be explained using mutually orthogonal XYZ Cartesian coordinates. One direction in the X-axis direction is referred to as the "+X side," and the other direction opposite to the one direction in the X-axis direction is referred to as the "-X side." One direction in the Y-axis direction is referred to as the "+Y side," and the other direction opposite to the one direction in the Y-axis direction is referred to as the "-Y side." One direction in the Z-axis direction is referred to as the "+Z side," and the other direction opposite to the one direction in the Z-axis direction is referred to as the "-Z side."

[0022] Figures 1 to 3 show the X-axis direction, Y-axis direction, and Z-axis direction, respectively. These directions are shown for convenience to explain the structure of the fiber-reinforced resin molded body 1 according to this embodiment and do not limit the manner in which the fiber-reinforced resin molded body 1 can be used according to the present invention. Furthermore, the X-axis direction corresponds to an example of the "longitudinal direction" in this disclosure. The Y-axis direction corresponds to an example of the "width direction" in this invention. The Z-axis direction corresponds to an example of the "thickness direction" in this invention.

[0023] As shown in Figure 1, the fiber-reinforced resin molded body 1 is a plate-like body having a length L, a thickness T, and a width W. The length L is the dimension along the X-axis of the fiber-reinforced resin molded body 1. The thickness T is the dimension along the Z-axis of the fiber-reinforced resin molded body 1. The width W is the dimension along the Y-axis of the fiber-reinforced resin molded body 1. The application of the fiber-reinforced resin molded body 1 is not particularly limited, but it can be used as a reinforcing material for products such as vehicles, aircraft, ships, electronic equipment, medical equipment, civil engineering and construction materials, home appliances, and tools. Furthermore, the fiber-reinforced resin molded body 1 has high adhesive strength with various materials such as fiber-reinforced resin molded bodies, concrete, metal, synthetic resin (plastic), wood, and glass via an adhesive, and can be used as a reinforcing material for products formed from various materials such as fiber-reinforced resin molded bodies, concrete, metal, synthetic resin, wood, and glass. Specifically, the +Z side of the fiber-reinforced resin molded body 1 is bonded to the target surface of a product formed from various materials, for example, with an epoxy resin adhesive.

[0024] The fiber-reinforced resin molded body 1 comprises a main body portion 10 and a plurality of protrusions 20. The main body portion 10 is a plate-like body having a length L, a thickness TA, and a width W. Specifically, the main body portion 10 has a virtual plane 11 that forms the boundary between the plurality of protrusions 20 and the main body portion 10, a bottom surface 12, a front side surface 13, a rear side surface 14, a right side surface 15, and a left side surface 16. The virtual plane 11 corresponds to an example of a "reference surface" in the present invention.

[0025] The virtual plane 11 and the bottom surface 12 are both planes perpendicular to the Z-axis direction, and the shapes of the virtual plane 11 and the bottom surface 12 are identical. The virtual plane 11 and the bottom surface 12 face each other in the Z-axis direction. The virtual plane 11 is positioned on the +Z side of the bottom surface 12. The area of ​​the virtual plane 11 is length L × width W.

[0026] As shown in Figures 2 and 3, the main body 10 includes a matrix resin 18 and reinforcing fibers 17. In Figure 2, only a portion of the reinforcing fibers 17 is shown. The matrix resin 18 is a thermosetting resin that has been cured by heat treatment. Various thermosetting resins can be used as the matrix resin 18, but epoxy resin is preferred, for example. Alternatively, a thermoplastic resin may be used as the matrix resin 18.

[0027] The reinforcing fibers 17 are embedded in the matrix resin 18. The reinforcing fibers 17 extend along the X-axis. Specifically, the reinforcing fibers 17 extend continuously from the front surface 13 to the rear surface 14.

[0028] Various fibers that contribute to reinforcing the fiber-reinforced resin molded body 1 can be used as the reinforcing fiber 17, but carbon fiber is preferred, for example. In the case of carbon fiber, it is more preferable to use PAN (polyacrylonitrile) based carbon fiber, which has relatively high strength, as the reinforcing fiber 17. Of course, pitch-based carbon fiber may also be used as the reinforcing fiber 17. Furthermore, it is also possible to use fibers other than carbon fiber, such as glass fiber, ceramic fiber, aramid fiber, basalt fiber, PBO fiber (poly(p-phenylenebenzoxazole) fiber), etc., as the reinforcing fiber 17.

[0029] Furthermore, the reinforcing fibers 17 are widely dispersed in the matrix resin 18. From the viewpoint of strength, the fiber volume content (Vf) of the main body 10 is preferably 50% or more and 80% or less. If the fiber volume content (Vf) of the main body 10 is less than 50%, the reinforcing effect of the reinforcing fibers may not be fully realized. On the other hand, if the fiber volume content (Vf) of the main body 10 exceeds 80%, the reinforcing fibers may separate from each other.

[0030] Referring again to Figures 1 to 3, the multiple protrusions 20 will be described in detail. As shown in Figure 1, each of the multiple protrusions 20 extends along the X-axis direction. Specifically, each of the multiple protrusions 20 extends continuously from the front surface 13 to the rear surface 14. Also, each of the multiple protrusions 20 projects from the virtual plane 11 toward the +Z side. Specifically, each of the multiple protrusions 20 is projected from the virtual plane 11 at a height TB. Furthermore, the multiple protrusions 20 are arranged on the virtual plane 11 so as to be adjacent to each other along the Y-axis direction.

[0031] Each of the multiple protrusions 20 extends continuously in the X-axis direction with a constant cross-section. Specifically, each of the multiple protrusions 20 can be a triangular prism, a rectangular prism, or a semi-cylindrical shape with an axis in the X-axis direction, but a triangular prism shape with an axis in the X-axis direction is preferred. The rectangular prism shape may be a trapezoid when viewed from the X-axis direction. The triangular prism shape may be an isosceles triangle or a right triangle when viewed from the X-axis direction. The surface area on the +Z side of the fiber-reinforced resin molded body 1 according to this embodiment is 110% to 200% of the area of ​​the virtual plane 11. The surface area on the +Z side of the fiber-reinforced resin molded body 1 according to this embodiment is substantially the same as the total area of ​​the inclined surfaces 21 of the multiple protrusions 20 described later. As a result, the area in contact between the +Z side surface of the fiber-reinforced resin molded body 1 and the adhesive increases. Therefore, the adhesive strength between the fiber-reinforced resin molded body 1 and the adhesive is improved.

[0032] Specifically, as shown in Figures 2 and 3, it is preferable that each of the multiple protrusions 20 has a slope 21 that moves further away from the virtual plane 11 as it moves toward the +Y or -Y side in the Y-axis direction. More specifically, the angle α between the slope 21 and the virtual plane 11 is 30° or more and 60° or less. If the angle α between the slope 21 and the virtual plane 11 is less than 30°, the adhesive strength between the fiber-reinforced resin molded body 1 and the adhesive may decrease. On the other hand, if the angle α between the slope 21 and the virtual plane 11 exceeds 60°, the adhesive may not reach the -Z side end of the slope 21, that is, the bottom of the valley formed between adjacent protrusions 20 when the adhesive is applied.

[0033] More specifically, the inclined surface 21 has a first inclined surface 21a that moves further away from the virtual plane 11 as it moves toward the +Y side in the Y-axis direction, and a second inclined surface 21b that moves further away from the virtual plane 11 as it moves toward the -Y side in the Y-axis direction. The first inclined surface 21a and the second inclined surface 21b are arranged alternately along the Y-axis direction. In other words, each of the multiple protrusions 20 is a triangular prism shape with an axis in the X-axis direction, and this triangular prism shape is an isosceles triangle when viewed from the X-axis direction. Specifically, the angle α between the first inclined surface 21a and the virtual plane 11 and the angle α between the second inclined surface 21b and the virtual plane 11 are the same. In this embodiment, since the first inclined surface 21a and the second inclined surface 21b are arranged alternately along the Y-axis direction, it is possible to further suppress the adhesive from not reaching the -Z side end (bottom of the valley) of the inclined surface 21 when the adhesive is applied.

[0034] Furthermore, the multiple protrusions 20 include a matrix resin 28 and reinforcing fibers 27 that extend continuously in the X-axis direction and are embedded within the matrix resin 28. The material of the matrix resin 28 is the same as the material of the matrix resin 18, and the material of the reinforcing fibers 27 is the same as the material of the reinforcing fibers 17.

[0035] The total fiber volume content (Vfs), which is the volume ratio of reinforcing fibers 17 and 27 in the fiber-reinforced resin molded body 1, is preferably 50% to 80% from the viewpoint of strength. Furthermore, the reinforcing fibers 27 are widely dispersed in the matrix resin 28. The difference obtained by subtracting the local fiber volume content (Vfp), which is the volume ratio of reinforcing fibers 27 in multiple protrusions 20, from the total fiber volume content (Vfs) is preferably less than 10%. As a result, a large amount of reinforcing fibers 27 are present in the multiple protrusions 20, and the reinforcing effect of the reinforcing fibers 27 can be fully exerted.

[0036] [Manufacturing method] The fiber-reinforced resin molded body 1 described above can be manufactured by the following method. Figure 4 is a schematic side view of a manufacturing apparatus 50 for manufacturing the fiber-reinforced resin molded body 1. As shown in Figure 4, the manufacturing apparatus 50 is a so-called pultrusion molding machine for manufacturing the fiber-reinforced resin molded body 1.

[0037] The manufacturing apparatus 50 comprises a feeder 51, a resin tank 52, a mold 54, a plurality of guides 530, and a take-up machine 55. The feeder 51, resin tank 52, the plurality of guides 530, the mold 54, and the take-up machine 55 are arranged in this order from the upstream side (left side in Figure 4) in the withdrawal direction. Here, the top and bottom of the manufacturing apparatus 50 are defined as shown in Figure 4, but this is not intended to limit the installation orientation of the manufacturing apparatus 50.

[0038] The feeder 51 is a device that supplies fiber bundles 30 to the resin tank 52. The feeder 51 includes a plurality of discharge rollers 511 around which the fiber bundles 30 are wound, and a guide 512 that guides the fiber bundles 30 that are discharged from each discharge roller 511 along the longitudinal direction (fiber direction) to the downstream side. Each discharge roller 511 discharges the fiber bundles 30 downstream by rotating. The plurality of fiber bundles 30 discharged from each discharge roller 511 are each guided by the guide 512 and led toward the resin tank 52 on the downstream side, where they are stacked vertically (thickness direction) on the upstream side of the resin tank 52.

[0039] Although Figure 4 shows a total of three feed rollers 511 for simplicity, the number of feed rollers 511, or in other words, the number of fiber bundles 30 to be stacked, can be appropriately set according to the target thickness T of the fiber-reinforced resin molded body 1 (Figure 1), and in practice, it can be set to a number significantly larger than three, such as several dozen.

[0040] The resin tank 52 is a tank for impregnating the fiber bundle 30 with uncured matrix resin 523. The uncured matrix resin 523 is an uncured thermosetting resin. For example, the matrix resin 523 can be an epoxy resin.

[0041] Multiple guide rollers 521 and 522 are arranged inside and outside the resin tank 52. The upstream guide roller 521 guides the fiber bundles 30 so that they are introduced into the resin tank 52 after being laminated. The downstream guide roller 522 leads the laminate of fiber bundles 30, which have been impregnated with matrix resin 523 by passing through the resin tank 52, to the downstream side of the resin tank 52 and guides it toward the mold 54. Hereinafter, the laminate of fiber bundles 30 led out of the resin tank 52, that is, the laminated fiber bundles 30 impregnated with uncured matrix resin 523, will be referred to as resin-impregnated fiber material 31.

[0042] Multiple guides 530 are positioned upstream of the mold 54. The multiple guides 530 guide the resin-impregnated fiber material 31 so that it is introduced into the die hole 542 of the mold 54, which will be described later.

[0043] Here, Figure 5 is a perspective view showing the mold 54 according to this embodiment. Although Figure 5 shows the X-axis, Y-axis, and Z-axis directions, these directions are shown for convenience in explaining the structure of the mold 54 according to this embodiment and do not limit the manner in which the mold 54 according to this disclosure can be used. As shown in Figure 5, the mold 54 is a mold that receives and heats the resin-impregnated fiber material 31. The mold 54 comprises a die 541 having die holes 542 inside and a heating device (not shown).

[0044] The die hole 542 penetrates the die 541 in the drawing direction. The shape of the die hole 542 corresponds to the fiber-reinforced resin molded body 1. The die hole 542 has a main hole 600 with a predetermined cross-section and a plurality of grooves 548 formed on the +Z side in the Z-axis direction of the main hole 600. Specifically, the main hole has a virtual plane 543, a bottom surface 544, a right side surface 546, and a left side surface 547. The virtual plane 543 corresponds to an example of a "reference plane" in this disclosure. The virtual plane 543 forms the boundary between the plurality of grooves 548 and the main hole 600.

[0045] Each of the multiple grooves 548 extends along the X-axis. Each of the multiple grooves 548 extends continuously in the X-axis direction with a constant cross-section. Furthermore, the multiple grooves 548 are arranged on the virtual plane 543 so that they are adjacent to each other along the Y-axis.

[0046] Furthermore, the surface area of ​​the die hole 542 on the +Z side is between 110% and 200% of the area of ​​the virtual plane 543. As a result, a fiber-reinforced resin molded body 1 can be obtained in which the surface area of ​​the fiber-reinforced resin molded body 1 on the +Z side is between 110% and 200% of the area of ​​the virtual plane 11 (see Figure 1).

[0047] The heating device raises the temperature of the inner wall of the die hole 542. The heating device heats the resin-impregnated fiber material 31 at least downstream of the mold 54 until the temperature of the matrix resin 523 exceeds its curing temperature. That is, the uncured matrix resin 523 contained in the resin-impregnated fiber material 31 hardens due to heating inside the mold 54. The resin-impregnated fiber material 31 inside the die hole 542 is shaped by heating with the heating device to have a cross-sectional shape corresponding to the die hole 542. This produces a fiber-reinforced resin molded body 1 having a plurality of protrusions 20 (see Figure 1). That is, the fiber-reinforced resin molded body 1 includes a plurality of fiber bundles 30 supplied from the delivery roller 511 of the feeder 51. As the plurality of fiber bundles 30 pass through the resin tank 52 and the mold 54, the matrix resin 523 impregnates and hardens the reinforcing fibers 17 and reinforcing fibers 27 contained in the plurality of fiber bundles 30, thereby forming the fiber-reinforced resin molded body 1. In other words, the fiber-reinforced resin molded body 1 includes reinforcing fibers 17 and 27, and thermosetting matrix resins 18 and 28 derived from the matrix resin 523.

[0048] As shown again in Figure 4, the take-up machine 55 is a device that takes up the fiber-reinforced resin molded body 1 discharged from the mold 54 and sends it further downstream. In this embodiment, the take-up machine 55 uses an endless belt 552, but any type of take-up machine that is appropriate to the shape of the fiber-reinforced resin molded body 1, such as a clamp type, can be used.

[0049] Next, with reference to Figure 6, the manufacturing procedure for the fiber-reinforced resin molded article 1 will be explained. Figure 6 is a flowchart summarizing the manufacturing procedure for the fiber-reinforced resin molded article 1 using the manufacturing apparatus 50 described above. As shown in Figure 6, the manufacturing method for the fiber-reinforced resin molded article 1 generally includes a first step S101, a second step S102, and a third step S103.

[0050] The first step S101 is the step of preparing the manufacturing apparatus 50. The manufacturing apparatus 50 includes, for example, a mold 54 as shown in Figure 4.

[0051] The second step S102 is a step in which a plurality of fiber bundles 30 are stacked and then passed through a resin tank 52 to obtain a resin-impregnated fiber material 31 in which a matrix resin 523 is impregnated into the stack of fiber bundles 30. The second step S102 is realized by a feeder 51 and a resin tank 52.

[0052] The third step S103 is a step in which a fiber-reinforced resin molded body 1 having a plurality of protrusions 20 is obtained by heating the resin-impregnated fiber material 31 while passing it through the mold 54. The third step S103 is carried out by the mold 54 and the take-up machine 55.

[0053] Through the processes S101 to S103 described above, a fiber-reinforced resin molded body 1 having a cross-sectional shape schematically shown in Figure 1 is manufactured. That is, a fiber-reinforced resin molded body 1 comprising a main body portion 10 and a plurality of protrusions 20 is manufactured.

[0054] [Effects and Effects] As described above, in this embodiment, the surface area of ​​the fiber-reinforced resin molded body 1 on the +Z side is 110% to 200% of the area of ​​the virtual plane 11, so the area in contact between the fiber-reinforced resin molded body 1 and the adhesive is increased. As a result, the adhesive strength between the fiber-reinforced resin molded body 1 and the adhesive is improved. In addition, since each of the multiple protrusions 20 contains reinforcing fibers 27, a decrease in strength can be suppressed. Furthermore, since the multiple protrusions 20 extend along the X-axis direction in which the reinforcing fibers 27 extend, the reinforcing fibers 27 are not cut compared to the case where the multiple protrusions 20 do not extend along the X-axis direction, so the generation of reinforcing fiber 27 chips and the like on the surface of the fiber-reinforced resin molded body 1 can be suppressed.

[0055] [Differentiation] Although preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and the following modifications are possible, for example.

[0056] (1) In the above embodiment, each of the multiple protrusions 20 was a triangular prism shape having an axis in the X-axis direction, but each of the multiple protrusions 20 may be a rectangular prism shape having an axis in the X-axis direction. The rectangular prism shape may be trapezoidal when viewed from the X-axis direction. An example of a case where the protrusions are trapezoidal is shown in Figure 7 as an enlarged cross-sectional view. The fiber-reinforced resin molded body 601 shown in Figure 7 comprises a main body 610 and a plurality of protrusions 620.

[0057] Each of the multiple protrusions 620 has a first slope 621a that moves further away from the virtual plane 611 as it moves toward the +Y side in the Y-axis direction, a second slope 621b that moves further away from the virtual plane 611 as it moves toward the -Y side in the Y-axis direction, and a plane 621c positioned between the first slope 621a and the second slope 621b. The angle α between the first slope 621a and the virtual plane 611 and the angle α between the second slope 621b and the virtual plane 611 are the same. The angle α is preferably between 30° and 60°. The plane 621c is perpendicular to the Z-axis direction. Each of the multiple protrusions 620 is projected from the virtual plane 611 at a height TC.

[0058] The +Z side surface area of ​​the fiber-reinforced resin molded body 601 in the modified example shown in Figure 7 is 110% to 200% of the area of ​​the virtual plane 611. Furthermore, the +Z side surface area of ​​the fiber-reinforced resin molded body 601 in the modified example is substantially the same as the total area of ​​the first inclined surface 621a, the second inclined surface 621b, and the plane 621c of the multiple protrusions 20. As a result, the contact area between the +Z side surface of the fiber-reinforced resin molded body 601 and the adhesive increases. Therefore, the adhesive strength between the fiber-reinforced resin molded body 601 and the adhesive is improved.

[0059] (2) In the above embodiment, multiple fiber bundles 30 were laminated and then passed through a resin tank 52 storing uncured matrix resin 523 to adhere (impregnate) the laminate of fiber bundles 30 with matrix resin 523. However, the method of adhering the matrix resin 523 is not limited to this. For example, the matrix resin 523 may be adhered to the laminate of fiber bundles 30 inside the mold 54 by injecting the uncured matrix resin 523 into the upstream part of the mold 54. In other words, the apparatus for adhering the matrix resin 523 to the laminate of fiber bundles 30 (resin adhesion apparatus) only needs to be an apparatus that can supply the matrix resin 523 so that the matrix resin 523 adheres to the laminate of fiber bundles 30 in or upstream of the mold 54, and the resin tank 52 is merely one example.

[0060] The present invention will be described in more detail below with reference to examples, but the scope of the present invention is not limited thereto. [Examples]

[0061] <Example 1> In the first step, a manufacturing apparatus was prepared in which a mold 54 was installed, which had a die hole 542 having a concave groove 548 with an isosceles triangle cross-section where the angle between the inclined surface 549 and the virtual plane 543 is 45° (see Figure 5). In the second step, fiber bundles 30 made of PAN-based carbon fibers were laminated and then passed through a resin tank 52 storing uncured epoxy resin to obtain a resin-impregnated fiber material 31 in which matrix resin 523 was impregnated into the laminate of fiber bundles 30 (see Figure 4). In the third step, the resin-impregnated fiber material 31 was heated while being passed through the die hole of the mold 54 to obtain a fiber-reinforced resin molded body 1 according to Example 1 (see Figure 1). The surface area on the +Z side of the fiber-reinforced resin molded body 1 according to Example 1, that is, the total surface area on the +Z side of all the protrusions 20, was 141% of the area of ​​the virtual plane 11. Furthermore, the total fiber volume content (Vfs) of the fiber-reinforced resin molded body 1 according to Example 1 was 70%.

[0062] <Example 2> In the first step, instead of setting up a mold 54 having a die hole 542 with a concave groove 548 having an isosceles triangle cross-section where the angle between the inclined surface 549 and the virtual plane 543 is 45°, a mold 54 having a die hole 542 with a concave groove 548 having an isosceles triangle cross-section where the angle between the inclined surface 549 and the virtual plane 543 is 30° was set up. Otherwise, the fiber-reinforced resin molded body 1 according to Example 2 was obtained in the same manner as in Example 1. The surface area on the +Z side of the fiber-reinforced resin molded body 1 according to Example 2 was 115% of the area of ​​the virtual plane 11. The total fiber volume content (Vfs) of the fiber-reinforced resin molded body 1 according to Example 2 was 70%.

[0063] <Example 3> In the first step, instead of setting up a mold 54 having a die hole 542 with a concave groove 548 having an isosceles triangle cross-section where the angle between the inclined surface 549 and the virtual plane 543 is 45°, a mold 54 having a die hole 542 with a concave groove 548 having an isosceles triangle cross-section where the angle between the inclined surface 549 and the virtual plane 543 is 60° was set up. Otherwise, the fiber-reinforced resin molded body 1 according to Example 3 was obtained in the same manner as in Example 1. The surface area on the +Z side of the fiber-reinforced resin molded body 1 according to Example 3 was 200% of the area of ​​the virtual plane 11. The total fiber volume content (Vfs) of the fiber-reinforced resin molded body 1 according to Example 3 was 70%.

[0064] <Example 4> In the first step, instead of using a mold 54 having a die hole 542 with a concave groove 548 having an isosceles triangular cross-section where the angle between the inclined surface 549 and the virtual plane 543 is 45°, a mold 54 having a die hole having a concave groove with a trapezoidal cross-section was used. Except for this, the process was the same as in Example 1, and a fiber-reinforced resin molded body 601 according to Example 4, as shown in Figure 7, was obtained. The angle α between the first inclined surface 621a and the virtual plane 611 and the angle α between the second inclined surface 621b and the virtual plane 611 were both 60°, and the surface area on the +Z side of the fiber-reinforced resin molded body 601 according to Example 4 was 158% of the area of ​​the virtual plane 611. The total fiber volume content (Vfs) of the fiber-reinforced resin molded body 601 according to Example 4 was 70%.

[0065] <Comparative Example 1> In the first step, a die 54 having a die hole 542 with a concave groove 548 having an isosceles triangular cross-section where the angle between the inclined surface 549 and the virtual plane 543 is 45° was replaced with a die 54 having a die hole with a square cross-section without a concave groove. The fiber-reinforced resin molded article according to Comparative Example 1 was obtained in the same manner as in Example 1. The surface area on the +Z axis side of the fiber-reinforced resin molded article according to Comparative Example 1 was 100% of the area of ​​the virtual plane. The total fiber volume content (Vfs) of the fiber-reinforced resin molded article according to Comparative Example 1 was 70%.

[0066] <Comparative Example 2> A fiber-reinforced resin molded article according to Comparative Example 2 was obtained by performing a polishing process on the +Z side of the fiber-reinforced resin molded article according to Comparative Example 1 using sandpaper with a grit size of #120. The total fiber volume content (Vfs) of the fiber-reinforced resin molded article according to Comparative Example 2 was 70%.

[0067] <Test Method 1> Tensile Adhesion Strength Using the fiber-reinforced resin molded articles from Examples 1 to 4 and Comparative Examples 1 to 2, two adherends measuring 25 mm in width, 100 mm in length, and 2.0 mm in thickness were prepared in accordance with JIS K6850. Then, test specimens from Examples 1 to 4 and Comparative Examples 1 to 2 were prepared by bonding a portion of the +Z side surface of one adherend to a portion of the +Z side surface of the other adherend using an epoxy resin adhesive.

[0068] Using a testing machine, the maximum load at which the bonded portion of the test specimens for Examples 1 to 4 and Comparative Examples 1 to 2 broke, separating the two test specimens, was measured. The tensile bond strength was defined as the maximum load at which the two test specimens separated divided by the bonded area. The tensile bond strengths are shown in Table 1.

[0069] <Test Method 2> Tensile Test of Concrete Pieces Using the fiber-reinforced resin molded bodies described in Examples 1 to 4 and Comparative Examples 1 to 2, a substrate measuring 25 mm in width, 100 mm in length, and 2.0 mm in thickness was prepared in reference to JIS K6850. Then, a portion of the +Z side surface of the substrate was bonded to a concrete piece measuring 25 mm in width, 100 mm in length, and 10 mm in thickness using epoxy resin adhesive to prepare test specimens described in Examples 1 to 4 and Comparative Examples 1 to 2.

[0070] Using a testing machine, the fracture of the adhesive portion of the test specimens for Examples 1 to 4 and Comparative Examples 1 to 2 was visually observed. A ○ was indicated when the concrete piece was destroyed without the test specimen detaching, and a × was indicated when the test specimen detached from the concrete piece. The results are shown in Table 1.

[0071] <Test Method 3> Fiber Volume Content Microscopic images of the protrusions of the fiber-reinforced resin molded articles according to Examples 1 to 4 were observed, and the local fiber volume content (Vfp) of multiple protrusions was calculated. The evaluation results are shown in Table 1.

[0072] <Test Method 4> Cross-sectional observation The cross-sections (surfaces) of the fiber-reinforced resin molded articles of Examples 1 to 4 and Comparative Examples 1 to 2 were observed according to the following criteria. The evaluation results are shown in Table 1. ○: No protrusion of reinforcing fibers from the surface of the fiber-reinforced resin molded body, and no cracks in the matrix resin near the surface. ×: There is either protrusion of reinforcing fibers from the surface of the fiber-reinforced resin molded product, or cracks in the matrix resin near the surface.

[0073] [Table 1]

[0074] <Test Results> As shown in Table 1, the tensile adhesive strength of the test specimen for Comparative Example 1 was 17.3 N / mm². 2 However, the tensile adhesive strength of the test specimens according to Examples 1 to 4 was 17.3 N / mm². 2 It was larger. In particular, the tensile adhesive strength of the test specimens according to Examples 1 to 3 was 20.0 N / mm². 2 The results were as described above, and were very large. From these results, it was found that when the surface area on the +Z side of the fiber-reinforced resin molded body was between 110% and 200% of the area of ​​the virtual plane, the adhesive strength between the fiber-reinforced resin molded body and the epoxy resin adhesive improved. Furthermore, it was found that when the shape of the convex part was a triangular prism, the adhesive strength between the fiber-reinforced resin molded body and the epoxy resin adhesive improved even further.

[0075] Furthermore, as shown in Table 1, the test specimens for Comparative Examples 1 and 2 peeled off from the concrete piece, but the test specimens for Examples 1 to 4 did not peel off, and the concrete piece was destroyed. In other words, the test specimens for Examples 1 to 4 did not peel off from the concrete piece even when the concrete piece was destroyed. From these results, it was found that when the surface area on the +Z side of the fiber-reinforced resin molded body was between 110% and 200% of the area of ​​the virtual plane, the adhesive strength between the fiber-reinforced resin molded body and the concrete piece improved.

[0076] Furthermore, as shown in Table 1, in the fiber-reinforced resin molded articles of Examples 1 to 4, the difference obtained by subtracting the local fiber volume content (Vfp) of multiple protrusions from the total fiber volume content (Vfs) of the fiber-reinforced resin molded article was less than 10%, meaning that a large amount of reinforcing fibers were present even in the multiple protrusions, and the reinforcing effect of the reinforcing fibers was fully demonstrated. In addition, although irregularities were formed on the +Z side surface of the fiber-reinforced resin molded article of Comparative Example 2, cracks were observed in the matrix resin near the surface, and reinforcing fibers were observed protruding from the +Z side surface of the fiber-reinforced resin molded article. [Explanation of symbols]

[0077] 1,601 Fiber-reinforced resin molded body 10, 610 Main unit 11, 611 Virtual plane (reference plane) 17, 27 Reinforced Fibers 18, 28 Matrix resin 20,620 convex part 54 Molding mold

Claims

1. A fiber-reinforced resin molded body that extends in the longitudinal direction and has constant dimensions in the width and thickness directions along the longitudinal direction, A main body comprising a matrix resin and reinforcing fibers contained within the matrix resin and extending continuously in the longitudinal direction, The main body comprises a matrix resin and reinforcing fibers contained within the matrix resin and extending continuously in the longitudinal direction, and includes a plurality of protrusions projecting from one side in the thickness direction of the main body, Each of the multiple protrusions extends continuously in the longitudinal direction with a certain cross-section and is arranged adjacent to one another in the width direction. The fiber-reinforced resin molded body wherein the surface area on one side in the thickness direction is 110% or more and 200% or less of the area of ​​the reference plane, which is a virtual plane forming the boundary between the plurality of protrusions and the main body.

2. The total fiber volume content, which is the volume ratio of the reinforcing fibers to the fiber-reinforced resin molded body, is 50% or more and 80% or less. The fiber-reinforced resin molded article according to claim 1, wherein the difference obtained by subtracting the local fiber volume content, which is the volume ratio of the reinforcing fibers in a plurality of protrusions, from the total fiber volume content is less than 10%.

3. Each of the multiple protrusions has a slope that moves further away from the reference plane towards one side or the other side in the width direction, The fiber-reinforced resin molded article according to claim 1, wherein the angle between the inclined surface and the reference surface is 30° or more and 60° or less.

4. The slope has a first slope that moves further away from the reference plane as it moves toward one side in the width direction, and a second slope that moves further away from the reference plane as it moves toward the other side in the width direction. The fiber-reinforced resin molded article according to claim 3, wherein the first inclined surface and the second inclined surface are arranged alternately along the width direction.

5. A step of preparing a mold having a die hole inside that extends in the longitudinal direction and whose width and thickness dimensions are constant along the longitudinal direction, A step of impregnating the reinforcing fibers that extend continuously in the longitudinal direction with an uncured matrix resin to obtain a resin-impregnated fiber material, The process includes a step of heating the resin-impregnated fiber material while passing it through the die hole in the longitudinal direction to obtain a fiber-reinforced resin molded body containing the matrix resin and the reinforcing fibers contained therein, The die hole has a main body hole with a predetermined cross-section and a plurality of grooves formed on one side of the main body hole in the thickness direction, Each of the aforementioned grooves has a constant cross-section and extends continuously in the longitudinal direction, and is arranged adjacent to one another in the width direction. A method for manufacturing a fiber-reinforced resin molded article, wherein the surface area on one side in the thickness direction of the die hole is 110% or more and 200% or less of the area of ​​the reference plane, which is a virtual plane forming the boundary between the plurality of grooves and the main body hole.

Images