Fiber reinforced plastic molding

Abstract

A fiber-reinforced plastic molded body characterized by comprising a laminate (A) which is a planar structure body containing a fiber-reinforced resin and a resin component (B) bonded to a part or the entire area of ​​the outer peripheral side surface of the laminate (A), wherein the laminate (A) has a sandwich structure component (E) in which one or more layers of a unidirectional fiber-reinforced resin (D) composed of unidirectional continuous fibers and a matrix resin are laminated on both surfaces of a core layer (C), and one or more layers of a woven fiber-reinforced resin (F) composed of woven fibers and a matrix resin are laminated on the design surface side surface of the unidirectional fiber-reinforced resin (D), and the resin component (B) is not substantially exposed in the projection plane from the woven fiber-reinforced resin (F) side. Provided is a fiber-reinforced plastic molded body which can improve the appearance design and can achieve smoothness by suppressing warping of the molded body while achieving thin-walled, high-strength, and high-rigidity in the case of an asymmetric laminated structure.

Description

Technical Field

[0001] The present invention relates to a fiber-reinforced plastic molded body suitable for use as parts and housings of personal computers, OA equipment, mobile phones, etc., where light weight, high strength, high rigidity, and thin wall thickness are required. Background Art

[0002] At present, with the development of portable electrical and electronic equipment such as personal computers, OA equipment, AV equipment, mobile phones, landline phones, fax machines, home appliances, toys, etc., further miniaturization and lightness are required. In order to achieve this requirement, it is necessary to avoid the shell from bending greatly when a load is applied to the components (especially the shell) constituting the device from the outside, so as to avoid contact with internal components and cause damage. Therefore, it is required to achieve high strength and high rigidity while also requiring thinning.

[0003] In addition, the housing of electronic devices such as notebook personal computers is visible to the human eye and directly touched by the user, so the design and surface appearance quality are highly valued. Therefore, the housing is usually decorated by exterior painting, and the surface quality is managed according to strict appearance standards. In recent years, the diversification of designs such as transparent metallic coatings and pearlescent transparent coatings has made progress. In order to meet the surface quality, advanced coating technology is required, and the quality requirements for the surface of molded products have also become more stringent. In particular, making the shape and pattern of the carbon fiber fabric as the fiber-reinforced substrate eye-catching and using a new surface pattern as a selling point is considered an important factor in promoting sales.

[0004] Patent document 1 describes a fiber reinforced plastic laminate, which is a fiber reinforced plastic laminate in which a skin material formed of reinforcing fibers and a matrix resin is stacked on at least a core material composed of a resin foam having independent foam cells. In the structure of the fiber reinforced plastic laminate, a unidirectional fiber reinforced plastic layer is arranged in at least one layer of the skin material with a thin plate thickness, and the skin material with a thick plate thickness has a stacked structure, and a fabric fiber reinforced plastic layer is arranged in at least one layer. As the upper surface skin material 3, a layer of prepreg blank A composed of fabric carbon fiber and epoxy resin is stacked on the outermost layer, and four layers of prepreg blank B composed of unidirectional carbon fiber and epoxy resin are stacked thereunder. The following effects obtained thereby are disclosed: while maintaining rigidity and lightness, the poor surface appearance caused by the occurrence of bubble voids, that is, bubble pores, generated inside the structure is suppressed, and the surface state of a good appearance with excellent design properties can be maintained.

[0005] In addition, Patent Document 2 records that a plate (A) having a single-side surface as a design surface is arranged in a mold on the inner side of a component (B) having a frame shape and is separated from the component (B) by at least a portion thereof, and a bonding resin (C) is injection-molded in a gap between the plate (A) and the component (B), thereby integrating the plate (A) and the component (B) at least at the outer peripheral edge of the plate (A). The following effects obtained thereby are disclosed: a plurality of structures are bonded with high bonding strength, and their bonding boundaries have good smoothness, and even if the molded body has components of the plate, warping can be reduced, thereby enabling lightweight and thin-walled products to be achieved.

[0006] In addition, Patent Document 3 records "a composite molded product (I), which is a composite molded product comprising a stacked component (II) having a sandwich structure and a resin component (III) arranged at least partially around the plate end of the stacked component (II), wherein the sandwich structure has a hard component layer (IIa) and a soft component layer (IIb), and in the joint between the stacked component (II) and the resin component (III), the resin component (III) is at least partially formed into a convex shape relative to the soft component layer (IIb)", and discloses that thereby, the effects of light weight, high rigidity, high strength and thin wall can be achieved.

[0007] In addition, Patent Document 4 describes a sandwich structure consisting of a skin layer and a core layer, wherein the core layer includes a fluid core layer formed by discontinuous fibers and a matrix resin (C), and in the structure of the sandwich structure, the skin layer is a fiber reinforced resin layer (X) formed by continuous fibers and a matrix resin (A), and the unidirectional fiber reinforced resin layer and the fabric fiber reinforced resin layer are stacked by more than one layer respectively, and the following effects obtained thereby are disclosed: it is lightweight, high-strength and high-rigidity, and can form vertical portions of complex shapes such as high-strength ribs in the out-of-plane direction of the skin layer by simple methods such as one-shot molding.

[0008] In addition, Patent Document 5 describes a "method for manufacturing a sandwich panel, wherein the sandwich panel comprises a core material and a skin material disposed on both sides of the core material and comprising a fiber-reinforced resin formed by impregnating a matrix resin in reinforcing fibers, wherein in the structure of the sandwich panel, the skin material is a fiber-reinforced resin having a layer structure of one layer or a stacked structure of multiple layers, at least one layer of the fiber-reinforced resin is a fiber-reinforced resin layer containing continuous reinforcing fibers, and the fiber-reinforced resin layer containing continuous reinforcing fibers comprises a fabric of reinforcing fibers", and discloses the following effects obtained thereby: the skin material is composed of a fiber-reinforced resin with high rigidity, the core material is composed of a resin having an apparent density lower than that of the skin material, and since the overall thickness is reduced, the panel has excellent lightness and X-ray transmittance while maintaining rigidity.

[0009] Prior art literature

[0010] Patent Literature

[0011] Patent Document 1: Japanese Patent Application Publication No. 2015-193119

[0012] Patent Document 2: International Publication No. 2018 / 110293 Pamphlet

[0013] Patent Document 3: Japanese Patent Application Laid-Open No. 61-24439

[0014] Patent Document 4: International Publication No. 2017 / 115640 Pamphlet

[0015] Patent Document 5: Japanese Patent Application Publication No. 2012-76464 Summary of the invention

[0016] Problems to be solved by the invention

[0017] The surface of the housing used in electrical and electronic equipment, and the parts constituting the equipment such as the housing, require high design and smoothness. For example, attempts have been made to arrange a sheet-like fiber-reinforced substrate such as a fabric on the surface of a fiber-reinforced plastic molded body to give a unique surface morphology to improve the design. However, in a fiber-reinforced plastic molded body, if a sheet-like fabric fiber-reinforced substrate such as a multiaxial fabric is used on the surface layer, the fabric pattern can be arranged on the surface, but because the carbon fibers of the fabric are in a wave-like shape, the strength such as bending rigidity is sometimes reduced.

[0018] Therefore, by setting the fiber reinforced plastic to a multilayer structure and consisting of a reinforcing base material and a sheet-like woven fiber reinforced base material such as a woven fabric or a multiaxial woven fabric, a certain strength and rigidity can be ensured. However, the molded body becomes an asymmetric stacked structure in the thickness direction, and sometimes the molded body itself warps due to the influence of thermal shrinkage after molding.

[0019] In addition, in order to solve this problem, a method of preforming the mold cavity into a shape that can offset the warping deformation of the fiber reinforced resin sheet caused by the difference in linear expansion coefficient is disclosed (for example, Japanese Patent Publication No. 2015-98173 and Japanese Patent Publication No. 2003-158143). However, the mold needs to be made into a special custom mold, and multiple trial productions need to be performed to confirm whether the shape is appropriate, which is a major factor leading to increased costs.

[0020] In order to solve such a problem, in the above-mentioned Patent Document 1, by configuring a skin material of unidirectional reinforced fiber plastic on both sides of the core material, the decrease in rigidity can be compensated. In addition, by configuring a fabric on the outermost layer of the skin material, high rigidity can be maintained and the appearance design can be improved. However, regarding reducing the warping of the molded body that is likely to occur due to the formation of an asymmetric stacking structure, Patent Document 1 does not recognize the problem related to this, nor does it provide any suggestions for countermeasures, and there is still room for improvement.

[0021] In addition, in Patent Document 2, the bonding resin (C) injected into the outer peripheral edge of the plate (A) is intended to bond the plate (A) and the component (B) with high strength. In addition, although an asymmetric stacking structure is recorded in which a thermoplastic resin layer (D) is provided on the outer surface of the plate (A) and the plate (A) and the bonding resin (C) are bonded via the thermoplastic resin layer (D), Patent Document 2 does not recognize the problem related to the warping of the molded body that may occur when the thermoplastic resin layer (D) is provided to form an asymmetric stack, nor does it provide any suggestions for countermeasures, and there is still room for improvement.

[0022] In addition, Patent Document 3 describes that the hard component layer (IIa) uses a sheet containing unidirectionally arranged continuous reinforcing fibers or a sheet containing continuous reinforcing fiber fabrics, and that the resin component (III) is injection molded around the plate end of the stacked component (II). However, there is no record of setting the stacked component (II) as an asymmetric stacked structure, nor is there any record suggesting the relationship between the injection-molded resin component (III) and the warping of the molded body. Regarding the warping of the molded body, Patent Document 3 does not recognize the problem related to this, nor does it suggest any countermeasures, and there is still room for improvement.

[0023] In addition, Patent Document 4 describes the following: the skin layer is a fiber-reinforced resin layer (X) formed of continuous fibers and a matrix resin (A), and is configured by laminating one or more unidirectional fiber-reinforced resin layers and one or more woven fiber-reinforced resin layers, thereby achieving light weight, high strength, and high rigidity characteristics. However, regarding the warping of the molded body that may occur when a woven fiber-reinforced resin layer is arranged on the surface layer of the skin material to form an asymmetric laminated structure, Patent Document 4 does not recognize the problem related to this, nor does it provide any suggestions for countermeasures, and there is still room for improvement.

[0024] Furthermore, in Patent Document 5, by providing the skin material with a fiber-reinforced resin layer including unidirectionally paralleled reinforcing fibers and woven reinforcing fibers, it is possible to design the strength and elastic modulus more efficiently. However, regarding the warping of the molded body that may occur when a woven fiber-reinforced resin layer is arranged on the surface layer of the skin material to form an asymmetric stacking structure, Patent Document 5 does not recognize the problem related to this, nor does it provide any suggestions for countermeasures, so there is still room for improvement.

[0025] In view of the above-mentioned problems of the prior art, the present invention aims to provide a fiber-reinforced plastic molded body in which a sheet-like textile fiber-reinforced substrate is arranged on the surface of a fiber-reinforced plastic molded body to impart a unique surface morphology to improve the design property, and in which, while having an asymmetric laminated structure, warping of the molded body is suppressed to achieve smoothness, and thinning, high strength and high rigidity are achieved.

[0026] Means for solving problems

[0027] In order to solve the above-mentioned problems, the present invention adopts the following means.

[0028] [1] A fiber-reinforced plastic molded body, characterized in that it is a fiber-reinforced plastic molded body composed of a laminate (A) which is a planar structure containing a fiber-reinforced resin, and a resin member (B) bonded to a part or the entire area of ​​an outer peripheral side surface of the laminate (A),

[0029] The laminate (A) comprises a sandwich structure component (E) in which one or more layers of a unidirectional fiber-reinforced resin (D) composed of unidirectional continuous fibers and a matrix resin are laminated on both surfaces of a core layer (C), and one or more layers of a woven fiber-reinforced resin (F) composed of woven fibers and a matrix resin are laminated on the design surface side surface of the unidirectional fiber-reinforced resin (D).

[0030] The resin member (B) is not substantially exposed in a projection plane from the side of the textile fiber-reinforced resin (F).

[0031] [2] The fiber-reinforced plastic molded body according to [1], characterized in that the textile fiber-reinforced resin (F), or the textile fiber-reinforced resin (F) and the unidirectional fiber-reinforced resin (D) laminated with the textile fiber-reinforced resin (F) have an extension portion exceeding the total width of the core layer (C), and the extension portion covers the resin part (B).

[0032] [3] The fiber-reinforced plastic molded product according to [2], further comprising a first bent portion in which the extended portion is bent to cover the resin member (B).

[0033] [4] The fiber-reinforced plastic molded product according to [1], characterized in that it has a second bent portion in which the end portion of the laminate (A) is covered with the resin member (B).

[0034] [5] The fiber-reinforced plastic molded product according to [3] or [4], wherein the first bent portion or the second bent portion covers at least a portion of an outer edge of the resin member (B).

[0035] [6] A fiber-reinforced plastic molded body according to any one of [1] to [5], characterized in that the laminate (A) is divided into two equal parts in the wall thickness direction, and the ratio Am2 / Am1 of the weight Am1 of the resin component (B) in the area (R1) closer to the design surface side than the divided center line to the weight Am2 of the resin component (B) in the area (R2) closer to the non-design surface side is in the range of 2 to 25.

[0036] [7] The fiber-reinforced plastic molded product according to any one of [1] to [6], wherein the bending rigidity of the sandwich structure component (E) is greater than the bending rigidity of the textile fiber-reinforced resin (F).

[0037] [8] The fiber-reinforced plastic molded body according to any one of [1] to [7], wherein the ratio Md / Mf of the bending modulus Md of the unidirectional fiber-reinforced resin (D) to the bending modulus Mf of the textile fiber-reinforced resin (F) is in the range of 1.2 to 17.

[0038] [9] A fiber-reinforced plastic molded body according to any one of [1] to [8], wherein the flexural modulus Md of the unidirectional fiber-reinforced resin (D) is in the range of 100 to 500 GPa, and the flexural modulus Mf of the textile fiber-reinforced resin (F) is in the range of 30 to 80 GPa.

[0039]

[10] The fiber-reinforced plastic molded body according to any one of [1] to [9], wherein the ratio Te / Tf of the wall thickness Te of the sandwich structure component (E) to the wall thickness Tf of the textile fiber-reinforced resin (F) is in the range of 1.2 to 40.

[0040]

[11] A fiber-reinforced plastic molded body according to any one of [1] to

[10] , wherein the wall thickness Te of the sandwich structure component (E) is in the range of 0.6 to 2 mm, and the wall thickness Tf of the textile fiber-reinforced resin (F) is in the range of 0.05 to 0.5 mm.

[0041]

[12] A fiber-reinforced plastic molded body according to any one of [1] to

[11] , wherein the laminate (A) and the resin component (B) are bonded via a bonding layer (G), and the bonding layer (G) is arranged on a part or the entire area of ​​the outer peripheral edge portion of the fiber-reinforced resin (D) on the non-design surface side of the laminate (A).

[0042]

[13] The fiber-reinforced plastic molded product according to any one of [1] to

[12] , wherein the core layer (C) is formed of any one of a resin foam and a porous substrate containing discontinuous fibers and a thermoplastic resin.

[0043] Effects of the Invention

[0044] According to the fiber reinforced plastic molded body of the present invention, a sheet-like fiber reinforcement substrate such as a woven fabric is arranged on the surface of the fiber reinforced plastic molded body to impart a unique surface morphology to improve the design properties, and while having an asymmetric laminated structure, the molded body can be smoothed while suppressing warping, and can also be thinned and have high strength and high rigidity. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] [ Figure 1 ] is a three-dimensional view of a fiber reinforced plastic molded body involved in one embodiment of the present invention.

[0046] [ Figure 2 ] is a top view showing an example of a base material of the textile fiber in the present invention

[0047] [ Figure 3a ] is a cross-sectional view (A) showing an example of a laminate (A) in the present invention, and is a cross-sectional view (B) showing an example of a state in which only the fabric fiber reinforced resin (F) layer exceeds the total width of the sandwich structure component (E).

[0048] [ Figure 3b ] is a cross-sectional view (A) showing an example of a laminate (A) of the present invention, and is a cross-sectional view (B) showing an example of a state in which only the fabric fiber reinforced resin (F) layer and the unidirectional fiber reinforced resin (D) on the design surface side exceed the total width of the sandwich structure component (E).

[0049] [ Figure 4a ] means along Figure 1 A cross-sectional view of an example of a fiber-reinforced plastic molded body according to the present invention, in a state where the textile fiber-reinforced resin (F) layer of the laminate (A) is bonded to the resin component (B) so that the design surface is covered.

[0050] [ Figure 4b ] means along Figure 1A cross-sectional view of an example of the fiber-reinforced plastic molded body according to the present invention, showing a state in which the textile fiber-reinforced resin (F) layer of the laminate (A) extends toward the side surface and is bonded to the resin member (B), as viewed along the line AA′.

[0051] [ Figure 5 ] is a cross-sectional view of an example of a fiber-reinforced plastic molded body according to the present invention, showing a state in which a bonding layer is formed on the surface of a unidirectional fiber-reinforced resin (D) of a stack (A) and a resin component (B) is bonded to the planar portions of the side portions and the outer peripheral edge portions of the stack (A).

[0052] [ Figure 6 ] is a cross-sectional view showing the state before the components of the stack (A) are arranged in a mold under pressure molding in the manufacturing process of the stack (A).

[0053] [ Figure 7 ] is a cross-sectional view showing a state in which a laminate (A) is formed by press molding by combining a press molding lower mold and a press molding upper mold.

[0054] [ Figure 8 ] is a process diagram showing the manufacturing process of a fiber reinforced plastic molded body, (A) is a cross-sectional view showing a state in which a laminate (A) is arranged in an injection molding mold, and (B) is a cross-sectional view showing a state in which a resin component (B) is injected from an injection gate to mold a fiber reinforced plastic molded body.

[0055] [ Fig. 9 ] is a process diagram showing the manufacturing process of a fiber reinforced plastic molded body in which a bonding layer (G) is provided and a resin component (B) is also bonded to a planar portion of the outer peripheral edge portion of a stack (A), and is a cross-sectional view showing the state before the components of the stack (A) are arranged in a mold under pressure molding.

[0056] [ Fig.10 ] means to continue Fig. 9 The process diagram of the process after the process is a cross-sectional view showing a state in which the press molding lower mold and the press molding upper mold are clamped together to form a laminate (A) by press molding.

[0057] [ Fig.11 ] is a process diagram showing the manufacturing process of a fiber reinforced plastic molded body which is joined to a resin part (B) in a manner covering the designed surface of a laminate (A), and is a cross-sectional view showing a laminate (A) arranged in an injection molding mold, and (B) is a cross-sectional view showing a state in which the resin part (B) is injected from an injection gate to mold the fiber reinforced plastic molded body.

[0058] [ Fig.12] is a process diagram showing the manufacturing process of a fiber reinforced plastic molded body in which a textile fiber reinforced resin (F) layer of a laminate (A) extends toward a side portion and covers a resin component (B), (A) is a cross-sectional view showing the laminate (A) arranged in an injection molding mold, and (B) is a cross-sectional view showing a state in which the resin component (B) is injected from an injection gate to mold the fiber reinforced plastic molded body.

[0059] [ Fig.13 ] is a schematic diagram showing a method for measuring the warpage of a fiber-reinforced plastic molding in the present invention. DETAILED DESCRIPTION

[0060] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings in conjunction with the embodiments. It should be noted that the present invention is not limited in any way by these drawings and the embodiments described below.

[0061] The fiber-reinforced plastic molded body 10 of the present invention is a fiber-reinforced plastic molded body 10 composed of a laminate (A) 20 as a planar structure containing a fiber-reinforced resin, and a resin component (B) 30 bonded to a part or the entire area of ​​the outer peripheral side surface of the laminate (A) 20, wherein the laminate (A) 20 has a sandwich structure component (E) 60 in which one or more layers of a unidirectional fiber-reinforced resin (D) 50 composed of unidirectional continuous fibers and a matrix resin are laminated on both surfaces of a core layer (C) 40, and one or more layers of a woven fiber-reinforced resin (F) 70 composed of woven fibers and a matrix resin are laminated on the design surface side surface of the unidirectional fiber-reinforced resin (D) 50, and the resin component (B) 30 is substantially not exposed in the projection plane from the woven fiber-reinforced resin (F) 70 side.

[0062] like Figure 1 As shown, the fiber reinforced plastic molded body 10 of the present invention comprises a laminate (A) 20 and a resin member (B) 30 composed of reinforcing fibers and a thermoplastic resin joined to a part or the entire area of ​​the outer peripheral side surface of the laminate (A) 20. In addition, a laminate (A) 20 having a design surface side surface laminated with a thermoplastic resin such as Figure 2 The woven fiber 70a shown is a structure of the woven fiber reinforced resin (F) 70. By disposing the woven fiber reinforced resin (F) 70 on the surface layer of the laminate (A) 20, the shape and pattern of the woven fabric are made to stand out and a unique surface morphology is given, thereby improving the design of the appearance.

[0063] Here, it is important that the resin member (B) 30 is not substantially exposed in the projection plane of the fiber-reinforced plastic molded body 10 from the side of the woven fiber-reinforced resin (F) 70. Figure 1It is important that in the projection plane in the direction of the arrow (Y), the resin member (B) 30 is not substantially exposed, that is, only the woven fiber reinforced resin (F) 70 is visible.

[0064] Here, the laminate (A) 20 is further described. An example of a cross-sectional view of the laminate (A) 20 is Figure 3a As shown. One or more layers of unidirectional fiber reinforced resin (D) 50 are laminated on both surfaces of the core layer (C) 40 to form a sandwich structure component (E) 60. Furthermore, any surface of the sandwich structure component (E) 60 is determined as a design surface, and a woven fiber reinforced resin (F) 70 is laminated on the design surface side surface to form a laminate (A) 20. By making the entire area of ​​the design surface side surface have a woven appearance, high design properties for electrical and electronic equipment can be expressed.

[0065] Here, in the present invention, it is preferred that the woven fiber reinforced resin (F) 70, or the woven fiber reinforced resin (F) 70 and the unidirectional fiber reinforced resin (D) 50 laminated with the woven fiber reinforced resin (F) 70 have an extension portion exceeding the total width of the core layer (C) 40, and the extension portion covers the resin part (B) 30.

[0066] like Figure 3a As shown in FIG. 1 , when a woven fiber reinforced resin (F) 70 having an extension portion exceeding the total width of the sandwich structure component (E) 60 is used, it is suitable for a case where the warpage of the laminate (A) 20 is relatively small, as described later, and when the fiber reinforced plastic molded body 10 is desired to be as lightweight as possible. On the other hand, when the warpage of the laminate (A) 20 is relatively large, and it is difficult to suppress the warpage with only the woven fiber reinforced resin (F) 70, as described below. Figure 3b As shown in FIG. 1 , it is preferable to provide an extended portion also on the unidirectional fiber-reinforced resin (D) 50 on which the woven fiber-reinforced resin (F) 70 is laminated.

[0067] It should be noted that, regarding the case where the extension portion is bent, Figure 3a As shown, when only the fabric fiber reinforced resin (F) 70 is bent, the bent portion is used as the first bent portion; Figure 3b As shown, when a part of the end portion or the entire layer of the sandwich structural member E (60) is bent, the bent portion is referred to as the second bent portion.

[0068] Such an extension portion can be formed by preparing in advance a unidirectional fiber reinforced resin (D) 50 or a woven fiber reinforced resin (F) 70 of a size exceeding the total width of the core layer (C) 40. Alternatively, the laminate (A) 20 may be manufactured to the size of the fiber reinforced plastic molded body 10, and the laminate (A) 20 may be cut in a manner to leave the extension portion by post-processing, or the unidirectional fiber reinforced resin (D) 50 on the surface of the core layer (C) 40 and the woven fiber reinforced resin (F) 70 not laminated may be cut. Alternatively, the extension portion may be formed by deforming the laminate (A) 20 during press molding or injection molding, or by deforming the laminate (A) 20 using a fixing jig.

[0069] As a method of bonding the resin member (B) 30 , various methods can be adopted. Figure 4a For Figure 3a The cross-sectional view of the fiber reinforced plastic molded body 10 in which the resin member (B) 30 is joined to the laminate (A) 20 shown has a structure in which the extended portion of the woven fiber reinforced resin (F) 70 covers the resin member (B) 30 .

[0070] In addition, it is preferable to have a bent portion in which the extended portion is bent and covered with the resin member (B) 30. Figure 4b As shown, the extended portion of the woven fiber reinforced resin (F) 70 can be bent toward the non-designed surface side, so that a portion of the resin member (B) 30 enters the inner side thereof and is covered. By forming such a bent shape, it is possible to Figure 1 In addition to the projection surface in the direction of the arrow (Y), the entire area also has a fabric appearance.

[0071] It should be noted that in the present invention, the resin component (B) 30 is not substantially exposed in the projection plane from the woven fiber reinforced resin (F) 70 side of the fiber reinforced plastic molded body 10, specifically, the maximum width of the resin component (B) 30 exposed in the projection plane from the woven fiber reinforced resin (F) 70 side of the fiber reinforced plastic molded body 10 is 5 mm or less. For the resin component (B) 30, when it is more than 5 mm away from the end of the product in the projection plane, the resin component (B) 30 can be visually recognized, so it is preferably 5 mm or less, more preferably 3 mm or less, and even more preferably 1 mm or less.

[0072] In addition, in the present invention, for the outer peripheral side surface where the laminate (A) 20 and the resin member (B) 30 are joined, it is not necessary to make the exposed width of the resin member (B) 30 uniform throughout the entire circumference, and the width can be changed according to the design of the product such as electrical and electronic equipment. In addition, by providing the extension only at the position where the design is required, mass productivity can be further improved.

[0073] Here, the outer peripheral side surface portion of the bonding resin member (B) 30 refers to an end surface portion having a perpendicular surface to the planar portion of the outer peripheral portion of the laminate (A) 20 of the planar structure. Figure 4a , Figure 4b In the illustrated embodiment, a part of the resin member (B) 30 is bonded to the outer peripheral side surface of the laminate (A) 20 .

[0074] The laminate (A) 20 used in the present invention has a fabric fiber reinforced resin (F) 70 laminated on the design surface side surface, and has an asymmetric laminated structure in the thickness direction. As described in detail below, the laminate (A) 20 is usually formed by press molding. Immediately after the press molding is completed, the laminate (A) 20 forms a shape that is roughly flat and free of warping, but sometimes, thereafter, the laminate (A) 20 is deformed downward into a convex shape due to thermal shrinkage caused by cooling. It is believed that the warping is caused by the fact that the fabric fiber reinforced resin (F) 70 laminated on the design surface side surface of the laminate (A) 20 is affected by thermal shrinkage and differs from the thermal shrinkage on the non-design surface side. When used in this state for the housing of an electrical equipment device, etc., it sometimes contacts internal components and causes a bad situation.

[0075] In order to suppress such warping, Figure 4a , Figure 4b or Figure 5 As shown in FIG. 1 , it is important to bond the resin member (B) 30 to a part or the entire area of ​​the outer peripheral side surface of the laminate (A) 20 formed by press molding. By thermally shrinking the resin member (B) 30 to offset the thermal shrinkage that tends to warp the laminate (A) 20, the fiber reinforced plastic molded body 10 as a whole can be smooth without warping.

[0076] In the present invention, the warpage of the fiber reinforced plastic molded body 10 is preferably 2.0% or less. Therefore, when the fiber reinforced plastic molded body 10 according to the present invention is used as a housing of an electronic device, high flatness can be maintained, and thinning and high strength can be achieved without contacting the internal electronic components.

[0077] Here, various materials constituting the fiber reinforced plastic molded body 10 will be described.

[0078] As the reinforcing fibers used in the unidirectional fiber-reinforced resin (D) 50 and the fabric fiber-reinforced resin (F) 70, high-strength and high-modulus fibers such as carbon fibers, glass fibers, alumina fibers, silicon carbide fibers, boron fibers, and silicon carbide fibers can be cited. In order to ensure lightness while maintaining high rigidity, carbon fibers with a high specific elastic modulus, which is the ratio of the elastic modulus to the density, are preferably used. For example, PAN-based, pitch-based, cellulose-based, hydrocarbon-based vapor-grown carbon fibers, graphite fibers, etc. can be used, and two or more of them can also be used in combination. PAN-based carbon fibers with excellent balance between rigidity and price are preferred.

[0079] In addition, in order to ensure high rigidity, for the unidirectional fiber-reinforced resin (D) 50 and the fabric fiber-reinforced resin (F) 70, from the aspect of the rigidity of the fiber-reinforced plastic molded body 10, it is preferable to use reinforcing fibers with a tensile elastic modulus in the range of 200 to 850 GPa. When the tensile elastic modulus of the reinforcing fiber is less than 200 GPa, it may not be possible to ensure the required high rigidity while maintaining lightness; when it is greater than 850 GPa, the compressive strength of the reinforcing fiber becomes weak and it is easily broken, so it is difficult to impregnate the matrix resin in the reinforcing fiber and mold the fiber-reinforced resin. If the tensile elastic modulus of the reinforcing fiber is within the above range, it is preferable in terms of further improving the rigidity of the laminate and the manufacturability of the reinforcing fiber.

[0080] In addition, the fiber fabric contained in the fabric fiber-reinforced resin (F) 70 is preferably at least one fabric selected from plain weave, twill weave, satin weave, and damask weave. Since the fabric fiber-reinforced resin (F) 70 has the characteristic of fiber pattern, the characteristic fiber pattern can be made prominent, and by using the fiber fabric on the outermost layer (design surface side), the shape pattern of the carbon fiber fabric can be made eye-catching and a new surface pattern can be presented.

[0081] In addition, as the matrix resin of the unidirectional fiber-reinforced resin (D) 50 or the fabric fiber-reinforced resin (F) 70, there is no particular limitation, and any of thermosetting resins and thermoplastic resins can be used.

[0082] When a thermosetting resin is used, unsaturated polyester resin, vinyl ester resin, epoxy resin, phenolic (resole type) resin, urea melamine resin, polyimide resin, maleimide resin, benzoxazine resin and other thermosetting resins can be preferably used. In particular, from the viewpoint of mechanical properties and heat resistance of the molded body, epoxy resin is preferred. In order to exhibit its excellent mechanical properties, it is preferred to include epoxy resin as the main component of the resin used, and specifically, it is preferred to include 60% by weight or more of epoxy resin relative to the resin composition.

[0083] In addition, when using a thermoplastic resin, polyester resins such as polybutylene terephthalate (PBT) resin, polytrimethylene terephthalate (PTT) resin, and liquid crystal polyester resins; polyolefin resins such as polybutene resin; polyarylene sulfide resins such as polyoxymethylene (POM) resin and polyphenylene sulfide (PPS) resin; polymethyl methacrylate (PMMA) resin, polyvinyl chloride (PVC) resin, polyphenylene ether (PPE) resin, polyimide (PI) resin, poly Amorphous resins such as polyamide-imide (PAI) resin, polyetherimide (PEI) resin, polysulfone (PSU) resin, polyethersulfone resin, polyarylate (PAR) resin, and thermoplastic elastomers such as phenolic resin, phenoxy resin, polystyrene resin, polyolefin resin, polyurethane resin, polyester resin, polyamide resin, polybutadiene resin, polyisoprene resin, fluorine resin, and acrylonitrile resin, and the like; thermoplastic resins in copolymers and modified products thereof. Among them, polyolefin resins are preferred from the viewpoint of lightness of the obtained molded article, polyamide resins are preferred from the viewpoint of strength, and amorphous resins such as polycarbonate resin, styrene resin, and modified polyphenylene ether resin are preferred from the viewpoint of surface appearance.

[0084] In addition, in the present invention, from the viewpoint of the moldability and strength of the laminate (A) 20, the fiber weight content of the unidirectional fiber-reinforced resin (D) 50 is preferably 50 to 80 weight %, and the fiber weight content of the woven fiber-reinforced resin (F) 70 is preferably 40 to 70 weight %.

[0085] If the fiber weight content of the unidirectional fiber-reinforced resin (D) 50 is less than 50% by weight, it may be difficult to exhibit the strength of the laminate (A) 20. If the fiber weight content of the unidirectional fiber-reinforced resin (D) 50 is more than 80% by weight, it may be difficult to handle as a prepreg due to the excessive amount of fiber. It is preferably 55 to 75% by weight, and more preferably 60 to 70% by weight.

[0086] If the fiber weight content of the textile fiber reinforced resin (F) 70 is less than 40% by weight, it may be difficult to exhibit the strength of the laminate (A) 20. If the fiber weight content of the textile fiber reinforced resin (F) 70 is more than 70% by weight, the design after molding may be impaired due to insufficient resin. It is preferably 45 to 65% by weight, and more preferably 50 to 60% by weight.

[0087] In addition, when laminating one or more layers of unidirectional fiber-reinforced resin (D) 50, it is preferable to laminate them so that the fiber orientation angles of adjacent unidirectional fiber-reinforced resin (D) 50 differ by 45 degrees or 90 degrees. By forming such a laminated structure, the fiber-reinforced plastic molded body 10 can be made thinner and lighter, and rigidity and strength above a certain level can be imparted.

[0088] In addition, the core layer (C) 40 used in the present invention is preferably formed by a resin foam or a porous substrate comprising discontinuous fibers and a thermoplastic resin. In such a configuration, the fiber-reinforced plastic molded body 10 can be made lightweight and highly rigid by making the core layer (C) 40 porous and having voids.

[0089] As the foam, polyurethane resin, phenolic resin, melamine resin, acrylic resin, polyethylene resin, polypropylene resin, polyvinyl chloride resin, polystyrene resin, acrylonitrile-butadiene-styrene (ABS) resin, polyetherimide resin or polymethacrylimide resin can be suitably used. Specifically, in order to ensure lightness, it is preferred to use a resin with an apparent density smaller than that of the skin layer, and polyurethane resin, acrylic resin, polyethylene resin, polypropylene resin, polyetherimide resin or polymethacrylimide resin can be particularly preferably used.

[0090] In addition, when using a composite comprising a thermoplastic resin and discontinuous fibers as the core layer (C) 40, it is preferred to prepare a core layer precursor comprising discontinuous fibers and a thermoplastic resin, heat and pressurize the core layer above the softening point or melting point of the thermoplastic resin, and then release the pressurization, so that the residual stress of the discontinuous fibers is released and they want to return to their original restoring force, the so-called rebound, causing them to expand in the thickness direction to form voids and become a composite.

[0091] As the discontinuous fibers used in the core layer (C) 40, the same type of reinforcing fibers as the above-mentioned continuous fibers can be used. The fiber length of the discontinuous fibers is preferably 1 mm or more and less than 150 mm. In the case of less than 1 mm, it is difficult to use as a substrate for the discontinuous fibers. On the other hand, if the fiber length is 150 mm or more, the deviation of the plate thickness of the fiber-reinforced plastic molded body 10 sometimes becomes large. The thermoplastic resin used in the core layer (C) 40 can also use the same type of resin as the above-mentioned thermoplastic resin.

[0092] In addition, in the present invention, the resin component (B) 30 is preferably composed of discontinuous carbon fibers or glass fibers and a thermoplastic resin. Thus, the laminate (A) 20 and the resin component (B) 30 constituting the fiber-reinforced plastic molded body 10 are joined with high joining strength, and the warpage of the fiber-reinforced plastic molded body 10 can be reduced.

[0093] The thermoplastic resin is preferably at least one thermoplastic resin selected from the above-mentioned polystyrene resin, polyamide resin, polycarbonate resin, polyester resin, polyethylene terephthalate resin, polyethylene resin and polypropylene resin. When a thermoplastic resin is used as a matrix resin of the unidirectional fiber reinforced resin (D) 50 or the woven fiber reinforced resin (F) 70 constituting the laminate (A) 20, the resin component of the resin member (B) 30 can be melted and integrated with the laminate (A) 20, and a strong bonding strength with the resin member (B) 30 can be obtained.

[0094] In addition, the fiber weight content of the resin part (B) 30 is preferably 5 to 30% by weight. This can improve the bonding strength and reduce the warpage of the fiber-reinforced plastic molded body 10. If it is less than 5% by weight, it may be difficult to ensure the strength of the fiber-reinforced plastic molded body 10; if it is more than 30% by weight, the filling of the resin part (B) 30 may become partially insufficient during injection molding. The fiber weight content is more preferably 8 to 28% by weight, and further preferably 12 to 25% by weight.

[0095] In addition, the weight-average fiber length of the discontinuous carbon fiber or glass fiber is preferably 0.3 to 3 mm. Here, continuous fibers and discontinuous fibers are defined. The so-called continuous fibers refer to the form in which the reinforcing fibers contained in the fiber-reinforced plastic molded body 10 are substantially continuously arranged throughout the entire length or width of the fiber-reinforced plastic molded body 10, and the so-called discontinuous fibers refer to the form in which the reinforcing fibers are intermittently divided and arranged. Generally speaking, unidirectional fiber-reinforced resin impregnated with resin in the reinforcing fibers that have been unidirectionally wired belongs to continuous fibers, and the SMC substrate used in press molding, the granular material contained in the reinforcing fibers used in injection molding, etc. belong to discontinuous fibers.

[0096] Among discontinuous fibers, as granular materials used in injection molding, they can be classified into two types: long fiber granules and short fiber granules. The long fibers treated in the present invention refer to fibers with a weight-average fiber length of more than 0.3 mm remaining in the parts composed of discontinuous fibers in the fiber-reinforced plastic molded body 10, and fibers less than 0.3 mm are defined as short fibers.

[0097] By making the remaining reinforcing fibers in the resin part (B) 30 long fibers, the effect of offsetting the warping of the fiber-reinforced plastic molded body 10 can be improved as described later. In the case of short fibers with a weight-average fiber length of less than 0.3 mm, there is sometimes a tendency for the strength of the resin part (B) 30 to decrease. If the weight-average fiber length is greater than 3 mm, the resin viscosity becomes high, and it is sometimes difficult to evenly fill the resin part (B) 30 into the corners of the molding mold during injection molding. The weight-average fiber length of the discontinuous carbon fiber or glass fiber is preferably 0.4 to 2.8 mm, more preferably 0.7 to 1.5 mm, and even more preferably 0.9 to 1.2 mm.

[0098] In addition, in the present invention, the stack (A) 20 is divided into two equal parts in the wall thickness direction, and the ratio Am2 / Am1 of the weight Am1 (g) of the resin component (B) 30 existing in the area (R1) closer to the design surface side compared to the divided center line and the weight Am2 (g) of the resin component (B) 30 existing in the area (R2) closer to the non-design surface side is in the range of 2 to 25.

[0099] exist Figure 4a , Figure 4b or Figure 5 In the figure, the dotted line of the core layer (C) 40 is the center line 120 that divides the wall thickness 110 of the laminate (A) 20 into two equal parts. If the above-mentioned Am2 / Am1 is less than 2, it is sometimes difficult to achieve the effect of offsetting warping. If Am2 / Am1 is greater than 25, the plate thickness of the molded body itself becomes thicker, and it is sometimes difficult to achieve thin-walling. Preferably, Am2 / Am1 is 5 to 22, more preferably Am2 / Am1 is 8 to 20, and further preferably 10 to 18. The resin part (B) 30 is preferably joined to the outer peripheral side portion of the laminate (A) 20 by injection molding. In addition, the amount of the above-mentioned resin part (B) 30 is specified by volume.

[0100] As a specific shape in which the above Am2 / Am1 is within the range of 2 to 25, it is preferred that at least a portion of the resin member (B) 30 has a vertical wall shape portion. Figure 4a , Figure 4b or Figure 5 As shown, the resin member (B) 30 disposed on the side surface of the fiber reinforced plastic molded body 10 has a vertical wall portion 100 extending downward, thereby making the fiber reinforced plastic molded body 10 a box-shaped body.

[0101] In addition, in the present invention, the bending rigidity of the sandwich structure component (E) 60 is preferably greater than the bending rigidity of the textile fiber reinforced resin (F) 70. By stacking the sandwich structure component (E) 60 with large bending rigidity, the strength of the fiber reinforced plastic molded body 10 can be ensured, and even if it is an asymmetric stacking structure, the occurrence of warping (even if small) can be suppressed. Bending rigidity is expressed as rigidity = elastic modulus × section inertia moment, which indicates the difficulty of deformation of the component relative to bending and torsion. Therefore, by specifying this bending rigidity, the correlation with warping can be expressed in a manner that takes into account the thickness and shape of the substrate.

[0102] In addition, in the present invention, when the bending modulus of the unidirectional fiber-reinforced resin (D) 50 is set to Md (GPa) and the bending modulus of the woven fiber-reinforced resin (F) 70 is set to Mf (GPa), Md / Mf is preferably 1.2 to 17. In this way, the strength of the molded body can be ensured, and the effect of offsetting warping can be obtained. If Md / Mf is less than 1.2, the effect of reducing warping sometimes becomes weak. If Md / Mf is greater than 17, the effect of reducing warping sometimes becomes weak. Md / Mf is preferably 3 to 16, more preferably 5 to 15, and further preferably 7 to 14.

[0103] In the present invention, it is preferred that the flexural modulus Md of the unidirectional fiber-reinforced resin (D) 50 is 100 to 500 GPa, and the flexural modulus Mf of the woven fiber-reinforced resin (F) 70 is 30 to 80 GPa. If the flexural modulus Md is less than 100 GPa, the laminate (A) 20 may be excessively warped, and the bonding with the resin component (B) 30 may be insufficient when the resin component (B) 30 is injection molded. If Md is greater than 500 GPa, it may be difficult to handle as a base material, and the material cost may be affected, resulting in a decrease in product competitiveness.

[0104] If Mf is less than 30 GPa, the strength of the fiber reinforced plastic molded body 10 may not be sufficiently ensured. If Mf is greater than 80 GPa, the laminate (A) 20 may be excessively warped, and the bonding with the resin part (B) 30 may become insufficient when the resin part (B) 30 is injection molded.

[0105] Md is preferably 120 to 480 GPa, more preferably 180 to 400 GPa, and even more preferably 220 to 320 GPa. Mf is preferably 35 to 75 GPa, more preferably 45 to 65 GPa, and even more preferably 50 to 60 GPa.

[0106] In addition, in the present invention, when the wall thickness of the sandwich structure component (E) 60 formed by sandwiching the two surfaces of the core layer (C) 40 with the unidirectional fiber reinforced resin (D) 50 is set to Te (mm), and the wall thickness of the textile fiber reinforced resin (F) 70 is set to Tf (mm), Te / Tf is preferably 1.2 to 40.

[0107] By increasing the wall thickness of the sandwich structural component (E) 60 including the unidirectional fiber-reinforced resin (D) 50 compared to the wall thickness of the woven fiber-reinforced resin (F) 70 , the influence of the thermal shrinkage of the woven fiber-reinforced resin (F) 70 can be reduced.

[0108] If Te / Tf is less than 1.2, it may be difficult to achieve the effect of offsetting warping. If Te / Tf is greater than 40, the thickness of the molded body itself becomes thick, and it may be difficult to achieve thin-walling. Te / Tf is preferably 2 to 35, more preferably 5 to 32, and even more preferably 8 to 30.

[0109] In the present invention, the wall thickness Te of the sandwich structure member (E) 60 is preferably 0.6 to 2 mm, and the wall thickness Tf of the woven fiber reinforced resin (F) 70 is preferably 0.05 to 0.5 mm. This is a range that can achieve both the effect of offsetting warpage and thinning.

[0110] If Te is less than 0.6 mm, the strength of the molded body itself may decrease. If Te is greater than 2 mm, the thickness of the molded body itself becomes thicker, and it is sometimes difficult to achieve thin-walling. If Tf is less than 0.05 mm, a poor appearance may occur. If Tf is greater than 0.5 mm, the thickness of the molded body itself becomes thicker, and it is sometimes difficult to achieve thin-walling.

[0111] Preferably, Te is 0.7 to 1.8 mm and Tf is 0.06 to 0.4 mm, more preferably, Te is 0.9 to 1.6 mm and Tf is 0.08 to 0.3 mm, and further preferably, Te is 1 to 1.4 mm and Tf is 0.1 to 0.2 mm.

[0112] In the present invention, it is preferred that the laminate (A) 20 and the resin member (B) 30 are bonded via a bonding layer (G) 80, and the bonding layer (G) 80 is disposed on a portion or the entire area of ​​the outer peripheral edge portion of the unidirectional fiber-reinforced resin (D) 50 on the non-design surface side of the laminate (A) 20. Figure 5 As shown, it is pre-attached to the surface of the unidirectional fiber reinforced resin (D) 50 on the non-designed surface side of the laminate (A) 20. When the resin component (B) 30 is injection molded, the bonding layer (G) 80 is melted by the melting heat of the resin component (B) 30, and can be bonded and integrated with the resin component (B) 30. The fiber reinforced plastic molded body 10 thus obtained can achieve high bonding strength.

[0113] exist Figure 5 In the embodiment, a portion of the resin component (B) 30 extends from the outer peripheral side surface of the laminate (A) 20 to the outer peripheral edge of the laminate (A) 20 to which the bonding layer (G) 80 is attached (resin component (B) 90), and is bonded to the bonding layer (G) 80. By expanding the bonding surface in this way, a stronger bonding strength can be achieved.

[0114] The bonding layer (G) 80 is not particularly limited, and a thermoplastic resin film or a thermoplastic resin nonwoven fabric can be used.

[0115] At this time, it is preferable to divide the laminate (A) 20 into two equal parts in the wall thickness direction, and to make the amount of the resin component (B) 30 existing in the region (R2) 140 on the side where the woven fiber reinforced resin (F) 70 is not laminated relative to the divided center line 120 to be greater by a certain ratio than the amount of the resin component (B) 30 existing in the region (R1) 130 on the side where the woven fiber reinforced resin (F) 70 is laminated. By making the amount of the resin component (B) 30 bonded to the outer peripheral edge and / or outer peripheral side surface of the fiber reinforced plastic molded body 10 as described above uneven, stress in the opposite direction to the warping of the laminate (A) 20 is generated due to the shrinkage of the resin component (B) 30, and the warping is offset as a whole. As a result, even if the laminate is asymmetrically laminated, the occurrence of warping during molding can be suppressed.

[0116] Next, the method for producing a fiber-reinforced plastic molded body of the present invention will be described with reference to the accompanying drawings. Figure 6 to Figure 8 Middle Pair Figure 4a , Figure 4b The method for manufacturing the fiber reinforced plastic molded body 10 shown in FIG. Figure 6 As shown, the woven fiber reinforced resin (F) 70, the unidirectional fiber reinforced resin (D) 50, the core layer (C) 40 and the unidirectional fiber reinforced resin (D) 50 prepared in advance are sequentially stacked on the lower press molding die 210 to form a precursor of the laminate (A) 20. The woven fiber reinforced resin (F) 70 and the unidirectional fiber reinforced resin (D) 50 are preferably in the form of a prepreg in which a thermosetting resin is impregnated in the reinforcing fibers, or in the form of a UD tape or woven fabric containing a thermoplastic resin.

[0117] Then, if Figure 7 As shown, the upper mold 220 for press molding is lowered to a position where it contacts the unidirectional fiber-reinforced resin (D) 50, and the precursor of the laminate (A) 20 is compression molded by a certain pressurizing pressure to produce the laminate (A) 20. At this time, it is also effective to sandwich a release film (not shown) between the mold and the precursor of the laminate (A) 20 to assist in demolding.

[0118] Then, if Figure 8As shown in (A), the laminate (A) 20 is arranged between the lower injection molding mold (M1) 230 and the upper injection molding mold (M1) 240 having a space 26 for forming the resin part (B) 30. Figure 8 As shown in (B), the resin member (B) 30 composed of reinforcing fibers and thermoplastic resin is injection molded from the injection gate 250. Thus, the resin member (B) 30 is joined and integrated with the side surface of the laminate (A) 20.

[0119] In addition, Figures 9 to 11 Middle pair setting Figure 5 The method for manufacturing a fiber reinforced plastic molded body in which the resin component (B) 90 is also bonded to the flat surface of the outer peripheral edge of the laminate (A) 20 by using the bonding layer (G) 80 shown. Fig. 9 As shown, the pre-prepared fabric fiber reinforced resin (F) 70, unidirectional fiber reinforced resin (D) 50, core layer (C) 40, unidirectional fiber reinforced resin (D) 50 and bonding layer (G) 80 are sequentially stacked on the lower mold 210 for press molding.

[0120] Then, if Fig.10 As shown, the upper press-molding die 220 is lowered to a position where it contacts the bonding layer (G) 80 , and the laminate (A) 20 is compression-molded by a certain pressurizing pressure to produce the laminate (A) 20 .

[0121] Then, if Fig.11 As shown in (A), the laminate (A) 20 is arranged between the lower injection molding mold (M1) 230 having a space 260 for forming the resin part (B) 30 and the upper injection molding mold (M2) 241. Fig.11 As shown in (B), the resin component (B) 30 composed of reinforcing fibers and thermoplastic resin is injection molded from the injection gate 250. As a result, the resin component (B) 30 is integrally bonded to the side surface of the stack (A) 20, and is integrally bonded to the planar portion of the outer peripheral edge of the stack (A) 20 via the bonding layer (G) 80.

[0122] Fig.12 In (A), the laminate (A) 20 is arranged between the lower injection molding mold (M2) 231 and the upper injection molding mold (M2) 241 having a space 260 for forming the resin part (B) 30. Next, as Fig.11 As shown in (B), the resin component (B) 30 composed of reinforcing fibers and thermoplastic resin is injection molded from the injection gate 250. As a result, the resin component (B) 30 is integrally bonded to the side surface of the stack (A) 20, and is integrally bonded to the planar portion of the outer peripheral edge of the stack (A) 20 via the bonding layer (G) 80.

[0123] Example

[0124] The fiber reinforced plastic molded body 10 of the present invention will be described in more detail below using examples, but the following examples do not limit the present invention. First, a method for measuring the characteristics of the present invention and examples of material compositions of various parts of the fiber reinforced plastic molded body 10 will be described.

[0125] (1) Determination of number average fiber length

[0126] The number average fiber length Ln of the reinforcing fibers contained in the resin part (B) 30 or the core layer (C) 40 is measured. A portion of the resin part (B) 30 or the core layer (C) 40 to be measured is cut out from the fiber-reinforced plastic molded body 10, and heated at 500°C in air for 60 minutes in an electric furnace to fully incinerate and remove the resin to separate only the reinforcing fibers. More than 400 fibers are randomly extracted from the separated reinforcing fibers. The fiber length of these extracted reinforcing fibers is measured using an optical microscope, and the length of 400 fibers is measured in units of 1 μm, and the number average fiber length Ln is calculated using the following formula.

[0127] Number average fiber length Ln = (ΣLi) / 400

[0128] Li: Fiber length (mm)

[0129] (2) Determination of fiber weight content

[0130] The fiber weight content of the woven fiber reinforced resin (F) 70, unidirectional fiber reinforced resin (D) 50, core layer (C) 40 or resin part (B) 30 constituting the laminate (A) 20 is measured by the following method. The woven fiber reinforced resin (F) 70, unidirectional fiber reinforced resin (D) 50, core layer (C) 40 or resin part (B) 30 to be measured is cut out from the fiber reinforced plastic molded body 10, and its weight w0 (g) is measured. Then, the cut sample is heated in air at 500°C × 1 hour to fully incinerate and remove the resin component, and the weight w1 (g) of the remaining reinforcing fiber is measured. The fiber weight content (wt%) is calculated using the following formula. The measurement is performed with n=3, and the average value is used.

[0131] Fiber weight content (wt%) = (weight of reinforcing fiber w1 (g) / weight of cut sample w0 (g)) × 100

[0132] (3) Determination of flexural rigidity and flexural elastic modulus

[0133] The bending modulus Md of the unidirectional fiber-reinforced resin (D) 50 and the bending modulus Mf of the woven fiber-reinforced resin (F) 70 were measured according to JIS K 7171. The bending rigidity of each member was calculated by bending modulus obtained by the above-mentioned bending modulus measurement×section moment of inertia / plate width.

[0134] (4) Determination of warpage

[0135] exist Fig.13 2 shows a method for measuring the warpage state of the fiber reinforced plastic molded body 10. The warpage of the fiber reinforced plastic molded body 10 is measured using a laser distance meter of BOSCH. First, the fiber reinforced plastic molded body 10 is placed on a flat plate 300 maintained horizontally. Then, a reference surface 320 on which the laser distance meter 310 can move is prepared above the fiber reinforced plastic molded body 10.

[0136] First, the distance between the reference plane 320 and the two extreme ends 330 and 340 of the fiber reinforced plastic molded body 10 is measured by the laser distance meter 310, and the line connecting the ends 330 and 340 is set as the warpage lower reference line 350. If the fiber reinforced plastic molded body 10 is, for example, a rectangular shape, the four sides are measured separately. As for the measurement position, the laser is irradiated near the outer peripheral ends of the four sides of the laminate (A) 20. The end is the end of the laminate (A) 20, and does not include the resin component (B) 30.

[0137] Next, the laser beam 310 is moved between the two end portions 330 and 340 at a constant equal interval, and the distance between the reference surface 320 and the fiber reinforced plastic molded body 10 at each location is measured. Fig.13 7 points are shown as an example of an odd number of points. At the location where the distance between the reference plane 320 and the fiber reinforced plastic molded body 10 is the shortest, a tangent line parallel to the warpage lower reference line 350 is set as the warpage upper reference line 360. When the distance between the two end portions 330 and 340 is set as L (mm), and the distance between the warpage lower reference line 350 and the warpage upper reference line 360 ​​is set as A (mm), it is defined by the following formula.

[0138] Warpage = (A / L) * 100 [%]

[0139] (Material Composition Example 1-1) Preparation of Unidirectional Fiber Reinforced Resin (D) 50

[0140] As a unidirectional fiber-reinforced resin (D) 50 in which PAN-based carbon fiber bundles are unidirectionally arranged in a sheet shape and impregnated with epoxy resin, a unidirectional prepreg (D-1) (manufactured by Toray Industries, Ltd., P3452S-15, carbon fiber weight content 67%, carbon fiber tensile modulus 235 GPa, thickness 0.15 mm), a unidirectional prepreg (D-2) (manufactured by Toray Industries, Ltd., P3452S-10, carbon fiber weight content 67%, carbon fiber tensile modulus 235 GPa, thickness 0.10 mm) and a unidirectional prepreg (D-3) (manufactured by Toray Industries, Ltd., P12453F-16, carbon fiber weight content 67%, carbon fiber tensile modulus 550 GPa, thickness 0.15 mm) were prepared. Separately, a unidirectional prepreg (D-4) (manufactured by Toray Industries, Inc., P12453F-11, carbon fiber weight content 67%, carbon fiber tensile modulus 550 GPa, thickness 0.10 mm) was prepared.

[0141] (Material Composition Example 1-2) Preparation of Textile Fiber Reinforced Resin (F) 70

[0142] As the woven fiber-reinforced resin (F) 70, a woven carbon fiber having a tensile elastic modulus of 230 GPa and an epoxy resin having a glass transition temperature of 135° C. and a unit area weight of 198 g / m 2 , a woven fabric prepreg (F-1) having a carbon fiber content of 56% by weight and a thickness of 0.10 mm.

[0143] (Material Composition Example 2-1) Preparation of Core Layer (C) 40

[0144] A core layer (C-1) 4 composed of foamed polypropylene (manufactured by Toray Industries, Ltd., RC2012W) was prepared.

[0145] (Material Composition Example 2-2) Preparation of Core Layer (C) 40

[0146] As a porous substrate, a core layer (C-2) 4 composed of discontinuous fibers (T700S manufactured by Toray Industries, Ltd., carbon fibers having a number average fiber length of 5 mm) and a thermoplastic resin (polypropylene) was prepared, wherein the weight content of the discontinuous fibers was 30% by weight.

[0147] (Material Composition Example 3) Preparation of Resin Part (B) 30

[0148] Glass fiber pellets for injection molding (GXV3540-UI manufactured by Teijin Limited, glass fiber, number average fiber length 0.2 mm, polycarbonate resin, fiber weight content 40 wt%) were prepared to prepare resin part (B-1) 3.

[0149] Glass fiber pellets for injection molding (manufactured by Toray Industries, Ltd., A503-F1, glass fiber, number average fiber length 0.2 mm, PPS resin, fiber weight content 30 wt%) were prepared to prepare a resin part (B-2) 3.

[0150] (Material Composition Example 4) Preparation of Bonding Layer (G) 80

[0151] A polyester resin ("Hytrel" (registered trademark) 4057 manufactured by Toray-DuPont Co., Ltd.) was fed from the hopper of a twin-screw extruder, melt-kneaded in the extruder, and extruded from a T-die. The film was then cooled and solidified by pulling with a cooling roll at 60°C to obtain a polyester resin film having a thickness of 0.05 mm. This was used as a thermoplastic bonding layer (G) 80.

[0152] (Example 1)

[0153] Using the unidirectional prepreg prepared in Material Composition Example 1-1 and the foamed polypropylene prepared in Material Composition Example 2-1, a 304 mm×304 mm rectangular sandwich structure component (E) 60 precursor was prepared by stacking in the order of [unidirectional prepreg (D-1) 0° / unidirectional prepreg (D-2) 90° / foamed polypropylene / unidirectional prepreg (D-2) 90° / unidirectional prepreg (D-1) 0°]. Next, 2 ply (2 layers) of the 304 mm×304 mm×0.1 mmt woven fabric prepreg (F-1) 70 prepared in Material Composition Example 1-2 were stacked on one side of the precursor of the sandwich structure component (E) 60, to prepare a precursor of a laminate (A) 20. Regarding the bending modulus Md of the unidirectional fiber-reinforced resin (D) 50, the elastic modulus of the cured prepreg stacked on the core layer (C) 50 with "unidirectional prepreg (D-1) 0° / unidirectional prepreg (D-2) 90°" was measured.

[0154] Then, if Figure 6 As shown in FIG. 1 , the precursor of the laminate (A) 20 is sandwiched by a release film (not shown) and placed on a 310 mm×310 mm rectangular lower press molding mold 210. Figure 7 As shown, after the upper die 220 for press molding is set, it is placed on a disk surface with a disk surface temperature of 150°C, the disk surface is closed, and heat pressurization is performed at 3MPa. After 5 minutes from the start of pressurization, the disk surface is opened to obtain a carbon fiber reinforced resin plate, i.e., a laminate (A-1) 20, which is formed into a rectangular flat plate shape of 1.8mm thick and 304mm×304mm.

[0155] Then, to become Figure 3aBy machining the outer periphery of the sandwich structural component (E) 60 using an NC machining machine as shown in the cross-sectional view, a laminate (A) is obtained in which the total width of only the woven fiber reinforced resin (F) 70 layers is extended compared to the sandwich structural component (E) 60.

[0156] Then, if Figure 8 As shown in (A), in the space formed by the injection molding lower mold 230 and the injection molding upper mold 240, the stacked body (A-1) 20 is arranged, as shown in FIG. Figure 8 As shown in (B), the resin part (B-1) 30 obtained in material composition example 3 is injection molded from the injection gate 250 in a manner such that Am1 / Am2 becomes 20, thereby manufacturing a fiber reinforced plastic molded body 10 in which the exposed width of the resin part (B-1) 30 from the projection plane is 3 mm.

[0157] (Example 2)

[0158] Using the unidirectional prepreg prepared in Material Composition Example 1-1 and the foamed polypropylene prepared in Material Composition Example 2-1, a 310 mm×310 mm rectangular sandwich structure component (E) 60 precursor was prepared by stacking in the order of [unidirectional prepreg (D-1) 0° / unidirectional prepreg (D-2) 90° / foamed polypropylene / unidirectional prepreg (D-2) 90° / unidirectional prepreg (D-1) 0°]. Next, 2 ply of the 310 mm×310 mm×0.1 mmt woven fabric prepreg (F-1) 70 prepared in Material Composition Example 1-2 was stacked on one side of the precursor of the sandwich structure component (E) 60, to prepare a precursor of a laminate (A) 20. Regarding the bending modulus Md of the unidirectional fiber-reinforced resin (D) 50, the elastic modulus of the cured prepreg stacked on the core layer (C) 50 with "unidirectional prepreg (D-1) 0° / unidirectional prepreg (D-2) 90°" was measured.

[0159] Then, if Figure 6 As shown in FIG. 1 , the precursor of the laminate (A) 20 is sandwiched by a release film (not shown) and placed on a 310 mm×310 mm rectangular lower press molding mold 210. Figure 7 As shown, after the upper die 220 for pressurization is set, it is placed on a plate surface with a plate surface temperature of 150°C, the plate surface is closed, and heat and pressurization are performed at 3MPa. After 5 minutes from the start of pressurization, the plate surface is opened to obtain a carbon fiber reinforced resin plate, i.e., a laminate (A-1) 20, which is formed into a rectangular flat plate shape of 0.5mm thick and 310mm×310mm.

[0160] Then, to become Figure 3aBy machining the outer periphery of the sandwich structural component (E) 60 using an NC machining machine as shown in the cross-sectional view, a laminate (A) is obtained in which the total width of only the woven fiber reinforced resin (F) 70 layers is extended compared to the sandwich structural component (E) 60.

[0161] Then, if Fig.12 As shown in (A), in the space formed by the injection molding lower mold 231 and the injection molding upper mold 240, the stacked body (A-1) 20 is arranged, as shown in FIG. Fig.12 As shown in (B), the resin part (B-1) 30 obtained in material composition example 3 is injection molded from the injection gate 250 in a manner such that Am1 / Am2 becomes 20, thereby manufacturing a fiber-reinforced plastic molded body 10 with high designability and coated with a layer of textile fiber-reinforced resin (F) 70 toward the non-design surface side.

[0162] (Example 3)

[0163] Using the unidirectional prepreg prepared in Material Composition Example 1-1 and the porous substrate prepared in Material Composition Example 2-2, a 310 mm×310 mm rectangular sandwich structure component (E) 60 precursor was prepared by stacking in the order of [unidirectional prepreg (D-1) 0° / unidirectional prepreg (D-2) 90° / porous substrate / unidirectional prepreg (D-2) 90° / unidirectional prepreg (D-1) 0°]. Next, 1 ply of the 310 mm×310 mm×0.1 mmt woven fabric prepreg (F-1) 70 prepared in Material Composition Example 1-2 was stacked on one side of the precursor of the sandwich structure component (E) 60, to prepare a precursor of a laminate (A) 20. Regarding the bending modulus Md of the unidirectional fiber-reinforced resin (D) 50, the elastic modulus of the cured prepreg stacked on the core layer (C) 50 with "unidirectional prepreg (D-1) 0° / unidirectional prepreg (D-2) 90°" was measured.

[0164] Then, if Figure 6 As shown in FIG. 1 , the precursor of the laminate (A) 20 is sandwiched by a release film (not shown) and placed on a 310 mm×310 mm rectangular lower press molding mold 210. Figure 7 As shown, after the upper die 220 for pressurization is set, it is placed on a plate surface with a plate surface temperature of 150°C, the plate surface is closed, and heat and pressurization are performed at 3MPa. After 5 minutes from the start of pressurization, the plate surface is opened to obtain a carbon fiber reinforced resin plate, i.e., a laminate (A-1) 20, which is formed into a rectangular flat plate shape of 0.5mm thick and 310mm×310mm.

[0165] Then, to become Figure 3bAs shown in the cross-sectional view, the outer periphery of the sandwich structural component (E) 60 is processed by an NC processing machine to obtain a laminate (A-1) 20 in which the woven fiber reinforced resin (F) 70 layer and a part of the sandwich structural component (E) 60 are extended.

[0166] Then, if Fig.12 As shown in (A), in the space formed by the injection molding lower mold 231 and the injection molding upper mold 240, the stacked body (A-1) 20 is arranged, as shown in FIG. Fig.12 As shown in (B), the resin part (B-1) 30 obtained in material composition example 3 is injection molded from the injection gate 250 in a manner such that Am1 / Am2 becomes 20, thereby manufacturing a fiber-reinforced plastic molded body 10 with high designability and coated with a layer of textile fiber-reinforced resin (F) 70 toward the non-design surface side.

[0167] (Example 4)

[0168] A laminate (A-1) 20 was prepared in the same configuration as in Example 1 with a size of 308 mm×305 mm.

[0169] Then, if Fig.12 As shown in (A), in the space formed by the injection molding lower mold 231 and the injection molding upper mold 240, the stacked body (A-1) 20 is arranged, as shown in FIG. Fig.12 As shown in (B), the resin part (B-1) 30 obtained in Material Composition Example 3 is injection molded from the injection gate 250 in a manner such that Am1 / Am2 becomes 22, thereby manufacturing a fiber-reinforced plastic molded body 10 with high designability, in which a textile fiber-reinforced resin (F) 70 layer is coated toward the non-design surface side and the exposed width of the resin part B becomes 2 to 5 mm.

[0170] (Comparative Example 1)

[0171] In Comparative Example 1, a laminate (A-1) 20 with a size of 270 mm × 270 mm was prepared in the same configuration as in Example 1. Next, injection molding was performed under the same conditions as in Example 1, and as a result, a fiber reinforced plastic molded body 10 with low design properties was obtained, in which a surface resin component (B-1) 30 was exposed with a width of 20 mm on the design surface side.

[0172] The above results are summarized in Table 1.

[0173] [Table 1]

[0174]

[0175] Industrial Applicability

[0176] The fiber-reinforced plastic molded article of the present invention can be effectively used for automobile interior and exterior decoration, housings of electric and electronic equipment, bicycles, structural parts for sporting goods, aircraft interior decoration parts, transportation boxes, and the like.

[0177] Description of Reference Numerals

[0178] 10 Fiber-reinforced plastic moldings

[0179] 20 Laminated body (A)

[0180] 30 Resin parts (B)

[0181] 40 Core Material(C)

[0182] 50 Unidirectional fiber reinforced resin (D)

[0183] 60 Sandwich laminated components (E)

[0184] 70 Textile fiber reinforced resin (F)

[0185] 71 Surface area of ​​textile fiber reinforced resin

[0186] 72 R-shaped area of ​​textile fiber reinforced resin

[0187] 70a Textile fiber base material

[0188] 70b 1st bending part

[0189] 70c Second bending part

[0190] 80 Bonding layer (G)

[0191] 90 A resin member (B) bonded to the flat surface of the outer peripheral edge of the laminate (A)

[0192] 100 vertical wall shape part

[0193] 110 Wall thickness of laminate (A) 20

[0194] 120 The center line of the segment

[0195] 130 Region (R1) on the side where the fabric fiber reinforced resin (F) is laminated

[0196] 140 Area (R2) on the side of the unlaminated fabric fiber reinforced resin (F)

[0197] 210 Pressurized lower mold

[0198] 220 Pressurized upper mold

[0199] 230 Injection molding lower mold (M1)

[0200] 231 Injection molding lower mold (M2)

[0201] 240 Injection molding upper mold (M1)

[0202] 241 Injection molding upper mold (MM2)

[0203] 250 Injection Gate

[0204] 260 Space for forming resin part (B)

[0205] 300 Tablet

[0206] 310 Laser Distance Meter

[0207] 320 datum plane

[0208] 330, 340 The two ends of the molded body

[0209] 350 Warp lower reference line

[0210] 360 Warp Upper Baseline

Claims

1. Fiber reinforced plastic moldings, It is characterized in that The fiber-reinforced plastic molded body comprises a laminate (A) which is a planar structure containing a fiber-reinforced resin, and a resin member (B) bonded to a part or the entire area of ​​the outer peripheral side surface of the laminate (A). The laminate (A) comprises a sandwich structure component (E) in which one or more layers of a unidirectional fiber-reinforced resin (D) composed of unidirectional continuous fibers and a matrix resin are laminated on both surfaces of a core layer (C), and one or more layers of a woven fiber-reinforced resin (F) composed of woven fibers and a matrix resin are laminated on the design surface side surface of the unidirectional fiber-reinforced resin (D). In the projection plane from the side of the textile fiber reinforced resin (F), the resin component (B) is not substantially exposed, The stack (A) is divided into two equal parts in the wall thickness direction, and the ratio Am2 / Am1 of the weight Am1 of the resin component (B) in the area (R1) closer to the design surface side than the divided center line and the weight Am2 of the resin component (B) in the area (R2) closer to the non-design surface side is in the range of 2 to 25.

2. The fiber-reinforced plastic molded body according to claim 1, It is characterized in that The woven fiber reinforced resin (F), or the woven fiber reinforced resin (F) and the unidirectional fiber reinforced resin (D) laminated with the woven fiber reinforced resin (F) have an extension portion exceeding the total width of the core layer (C), and the extension portion covers the resin component (B).

3. The fiber-reinforced plastic molded body according to claim 2, It is characterized in that The extending portion is bent to cover the resin member (B) and has a first bent portion.

4. The fiber-reinforced plastic molded body according to claim 1, It is characterized in that The end portion of the laminate (A) is provided with a second bent portion covered with the resin member (B).

5. The fiber-reinforced plastic molded body according to claim 3, in, The first bent portion covers at least a portion of an outer edge of the resin member (B).

6. The fiber-reinforced plastic molded body according to claim 4, in, The second bent portion covers at least a portion of the outer edge of the resin member (B).

7. The fiber-reinforced plastic molded product according to any one of claims 1 to 4, in, The flexural rigidity of the sandwich structural component (E) is greater than the flexural rigidity of the textile fiber reinforced resin (F).

8. The fiber-reinforced plastic molded product according to any one of claims 1 to 4, in, A ratio Md / Mf of a flexural modulus Md of the unidirectional fiber-reinforced resin (D) to a flexural modulus Mf of the textile fiber-reinforced resin (F) is in the range of 1.2 to 17.

9. The fiber-reinforced plastic molded product according to any one of claims 1 to 4, in, The unidirectional fiber-reinforced resin (D) has a bending elastic modulus Md in the range of 100 to 500 GPa, and the flexural elastic modulus Mf of the textile fiber-reinforced resin (F) is in the range of 30 to 80 GPa.

10. The fiber-reinforced plastic molded product according to any one of claims 1 to 4, in, The ratio Te / Tf of the wall thickness Te of the sandwich structure component (E) to the wall thickness Tf of the textile fiber reinforced resin (F) is in the range of 1.2 to 40.

11. The fiber-reinforced plastic molded product according to any one of claims 1 to 4, in, The wall thickness Te of the sandwich structure component (E) is in the range of 0.6 to 2 mm, and the wall thickness Tf of the textile fiber reinforced resin (F) is in the range of 0.05 to 0.5 mm.

12. The fiber-reinforced plastic molded product according to any one of claims 1 to 4, in, The laminate (A) and the resin component (B) are bonded via a bonding layer (G), and the bonding layer (G) is arranged on a part or the entire area of ​​the outer peripheral edge portion of the unidirectional fiber-reinforced resin (D) on the non-design surface side of the laminate (A).

13. The fiber-reinforced plastic molded product according to any one of claims 1 to 4, in, The core layer (C) is formed of either a resin foam or a porous base material containing discontinuous fibers and a thermoplastic resin.

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