JP2017006680A - Jointing method for jointing fiber-reinforced thermoplastic resin material and joint object, and fiber-reinforced plastic product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel jointing method for jointing a fiber-reinforced thermoplastic resin material and a joint object such as a metal.SOLUTION: A jointing method for jointing a fiber-reinforced thermoplastic resin material 11a, in which a thermoplastic resin cyclic oligomer is made matrix, and a joint object 80 is characterized by comprising: an installation step of setting a press molding mold 50 capable of being heated to a predetermined temperature, with one or two or more sheet-shaped fiber-reinforced thermoplastic resin material of fibers impregnated with a thermoplastic resin cyclic oligomer as a matrix, and a joint object; a heating step of heating the fiber-reinforced thermoplastic resin material disposed in the molding mold; and a compression step of ring-opening polymerizing the thermoplastic resin cyclic oligomer of the fiber-reinforced thermoplastic resin material, into a predetermined shape.SELECTED DRAWING: Figure 6

Description

  The present invention relates to home appliances, electronic equipment, medical equipment, health equipment, sports equipment, vehicle-mounted parts, building materials, structural equipment, and pachinko gaming machines, arrange ball gaming machines, sparrow ball gaming machines, medals or pachinko balls. The present invention relates to a method for joining a fiber reinforced thermoplastic resin material used for a game machine provided as a game machine or the like used as a game medium, and other industrial equipment, and an object to be joined such as metal.

  Conventionally, fiber reinforced thermoplastic resins reinforced with reinforcing fibers such as carbon fibers, glass fibers, and aramid fibers have been widely used in various fields as materials having excellent product thickness reduction, weight reduction, strength, and rigidity. However, there is a drawback that mass production of complicated shapes is not suitable.

  In order to solve these disadvantages and to have a complicated shape and functionality, there is a demand for a joining technique that integrates a fiber-reinforced thermoplastic resin and an object to be joined such as metal or plastic. In order to join the fiber reinforced thermoplastic resin and the metal member, the thermoplastic resin itself used as a matrix in the composite material needs to be firmly joined (for example, fused) to the metal surface.

  For example, Patent Document 1 discloses that a metal frame and a rib made of a thermoplastic resin are integrated by inserting a metal frame coated with an epoxy resin-based paint into an injection mold and then injection-molding the rib. The electronic equipment housing joined to the is described.

  Patent Document 2 discloses that a metal frame and a rib made of a thermoplastic synthetic resin are formed by inserting a metal frame treated with a reducing agent with hydrazine or the like into an injection mold and then injection-molding the rib. An electronic device housing that is integrally bonded is described.

  However, the method using the adhesive of Patent Document 1 requires an adhesive preparation step and an application step, so that it is difficult to reduce the production cost and sufficient reliability of the adhesive strength is not obtained. . Moreover, the method described in Patent Document 2 requires a surface treatment using a reducing agent in advance, and it is difficult to reduce production costs.

JP 2001-298277 A JP 2003-103563 A

  The present invention has been made in view of the above problems, and the present inventor has found that a fiber-reinforced thermoplastic resin material using a thermoplastic resin cyclic oligomer as a matrix is firmly bonded by a predetermined joining method, An object of the present invention is to provide a novel joining method between a reinforced thermoplastic resin material and a joining object such as a metal.

  The present invention adopts the following means in order to achieve the above-mentioned object.

A joining method for joining a fiber reinforced thermoplastic resin material and a joining object using a thermoplastic resin cyclic oligomer according to the present invention as a matrix,
An installation step of installing one or two or more sheet-like fiber reinforced thermoplastic resin materials impregnated into a fiber with a thermoplastic resin cyclic oligomer as a matrix and an object to be joined in a press mold that can be heated to a predetermined temperature;
A heating step of heating the fiber-reinforced thermoplastic resin material installed in the mold;
A pressurizing step for shaping the thermoplastic resin cyclic oligomer of the fiber reinforced thermoplastic resin material into a predetermined form by ring-opening polymerization;
It is characterized by comprising.

In the case of a resin material made of a polymer, it cannot be bonded simply in contact with the surface or has a very weak adhesive force. However, according to the joining method of joining the fiber reinforced thermoplastic resin material and the object to be joined using the thermoplastic resin cyclic oligomer according to the present invention as a matrix, the metal, plastic or other material is brought into contact with the fiber reinforced thermoplastic resin material. By molding under a predetermined condition in a state of being made, it is possible to obtain a high bonding strength that cannot be obtained when molding simultaneously with a thermoplastic polymer resin. Further, even a bonded product that cannot be bonded with a polymer thermoplastic resin can be bonded with high strength. Furthermore, when the thermoplastic resin cyclic oligomer is heated, the viscosity becomes considerably low and the fluidity is too high. Therefore, when the thermoplastic resin cyclic oligomer is produced with a press type mold, the thermoplastic resin cyclic oligomer flows out of the mold or the resin is biased. In spite of the possibility of being a material unsuitable for press-type molding, according to the joining method of the present invention, the viscosity is increased by polymerizing a part of the thermoplastic oligomer by the one-end heating process. Thus, after the fluidity is lowered, the molding is performed in the pressurizing process which is the final fastening, so that these problems can be solved.

  Moreover, in the joining method which joins the fiber reinforced thermoplastic resin material and joining object concerning this invention, the said heating process is 10%-70% ring-opening polymerization of a thermoplastic resin cyclic oligomer, It is characterized by the above-mentioned. It may be. By employ | adopting this structure, it can be set as the state which has a viscosity suitable for shaping | molding in a pressurization process.

  Furthermore, in the joining method which joins the fiber reinforced thermoplastic resin material and joining object concerning this invention, the said heating process may be characterized by heating for 1 minute-2 minutes. By adopting such a configuration, it is possible to provide an optimal time for 10% to 70% ring-opening polymerization of the thermoplastic resin cyclic oligomer.

  Furthermore, in the joining method for joining the fiber-reinforced thermoplastic resin material and the joining object according to the present invention, the pressure step is a position where the fiber-reinforced thermoplastic resin material is thinner than the state where the fiber-reinforced thermoplastic resin material is installed in the installation step. It may be characterized in that it is clamped up to. The present invention uses a fiber reinforced thermoplastic resin material in which a thermoplastic resin cyclic oligomer that becomes low viscosity when heated is used as a matrix, but in part to the extent that the resin can be prevented from flowing out by the heating process. Since pressurization is performed in a polymerized state, the pressurization can be performed so as to be thinner than the initial thickness of the fiber-reinforced thermoplastic resin material. Therefore, it is possible to produce a molded article having higher strength and firmly joined to the joining object and the fiber reinforced thermoplastic resin material.

  Moreover, the fiber reinforced plastic product according to the present invention is produced by a joining method for joining a fiber reinforced thermoplastic resin material and a joining object. A fiber reinforced plastic product characterized in that a fiber reinforced thermoplastic resin material comprising a thermoplastic resin cyclic oligomer according to the present invention as a matrix and the fiber reinforced thermoplastic resin material are bonded together. Without including an adhesive component other than the resin material, it is possible to provide a molded article having higher strength and firmly joined to the object to be joined and the fiber reinforced thermoplastic resin material.

  According to the joining method for joining the fiber reinforced thermoplastic resin material and the joining object according to the present invention, the joining method for joining the fiber reinforced thermoplastic resin material and the joining object using the thermoplastic resin cyclic oligomer as a matrix. According to the present invention, it is possible to obtain a bonding strength that cannot be obtained by molding at the same time as the polymer thermoplastic resin. Furthermore, even a bonded material that cannot be bonded by the polymer thermoplastic resin has a high strength. Can be joined.

FIG. 1 is a perspective view of an outer frame according to the embodiment. FIG. 2 is an end view of the mold 50 according to the embodiment. FIG. 3 is a diagram illustrating a part of the process of the bonding method according to the embodiment. FIG. 4 is a diagram illustrating a part of the process of the bonding method according to the embodiment. FIG. 5 is a diagram illustrating a part of the process of the bonding method according to the embodiment. FIG. 6 is a diagram illustrating a part of the process of the bonding method according to the embodiment. FIG. 7 is a graph showing the results of a tensile bond strength test according to Example 1. FIG. 8 is a graph showing the results of a tensile shear bond strength test according to Example 2.

(Embodiment)
A mode for carrying out the present invention will be described in detail based on the above-described briefly described drawings.

(Embodiment)
The present invention relates to a joining method for joining a sheet-like fiber-reinforced thermoplastic resin material having a thermoplastic resin cyclic oligomer as a matrix to a fiber and an object to be joined. First, the fiber reinforced thermoplastic resin material and the object to be joined used in the joining method of the present invention will be described first.

  The fiber reinforced thermoplastic resin material includes a fiber and a thermoplastic resin cyclic oligomer impregnated in the fiber.

  As the fiber material, glass fiber, carbon fiber, plastic fiber such as aramid fiber, natural fiber, or a mixture thereof can be used. The material is not limited to these. The fiber may be either a long fiber or a short fiber. In the case of a long fiber, it may be a unidirectional continuous fiber or a woven fabric. In the case of woven fabrics, plain weaving that provides uniform strength in any direction, twill weaving that increases strength in an oblique direction by shifting the intersection of warp and weft at a specific interval, and warp and weft alternately intersect Alternatively, any weaving method such as a satin weave with a large interval between the intersections may be used. In the case of a short fiber, a fiber web, a nonwoven fabric, etc. can be used.

  A thermoplastic resin cyclic oligomer is a material that undergoes a polymerization reaction according to the temperature of a molding die and is finally processed into a thermoplastic polymer resin by molding. For example, as a cyclic polyester oligomer, a cyclic polyethylene terephthalate oligomer or a cyclic polybutylene is used. Examples include cyclic polyalkylene arylate oligomers such as terephthalate oligomers and cyclic polypropylene terephthalate oligomers, and cyclic polycyclohexanedimethylene terephthalate. Moreover, cyclic polyphenylene sulfide oligomers, cyclic polyphenylene sulfide sulfone oligomers, cyclic polyphenylene sulfide ketone oligomers, cyclic polyarylene sulfide oligomers such as cyclic polyphenylene sulfide ether oligomers, other cyclic polycarbonate oligomers, etc., and at least selected from these groups Includes one kind. Of course, the present invention is not limited to this, and any thermoplastic resin cyclic oligomer that becomes a polymer by a polymerization reaction in the mold can be used.

  When the cyclic polyester oligomer is used, the average degree of polymerization is preferably about 2 to 35, and more preferably 5 to 20. In addition, the cyclic polyester oligomer having a melting point of about 50 ° C. to 250 ° C. can be suitably used for molding.

  The cyclic polyester oligomer includes two or more kinds selected from the group listed as the cyclic polyester oligomer described above, and if necessary, other resins not included in the group of cyclic polyester oligomers and various additives. Further, it may contain a polymerization accelerator, a catalyst for promoting ring-opening polymerization such as tin, and the like.

  The fiber-reinforced thermoplastic resin material used in this production method is produced in a sheet form by impregnating the above-described fibers with a thermoplastic resin cyclic oligomer. A well-known technique can be used for the method of impregnating the thermoplastic resin cyclic oligomer into the fiber reinforced thermoplastic resin material. For example, as a method for producing a prepreg, a method described in JP-T-2011-516654 is cited.

  As the joining object, various materials can be used as long as they can withstand the heat of the mold, such as synthetic resins such as polycarbonate or ABS resin, metals such as SUS, aluminum and brass, glass and rubber. Further, the form of the object to be joined may be a form such as a boss, a flanged boss, a plate-like object such as a rib, or a base member for mounting, or a sheet coated on the surface of a fiber reinforced thermoplastic resin material. Or a film.

  Next, the molding die 50 used for joining the sheet-like fiber-reinforced thermoplastic resin material 11a thus produced and the joining object 80 will be described.

  In the present embodiment, as shown in FIG. 1, as a fiber reinforced plastic product, the upper frame connecting bracket 20 is attached to the outer frame 11 on the side surface of the outer frame 10 to which a pachinko gaming machine body (not shown) is attached. A description will be given by taking as an example a product to which the receiving metal fitting 30 and the front plate connecting metal fitting 40 are attached. The outer frame 11 according to the present embodiment is made of a fiber reinforced thermoplastic resin material 11a (see FIG. 4), and the upper frame connecting bracket 20, the receiving bracket 30, and the front plate connecting bracket 40 correspond to the joining object 80, respectively. To do. In the present embodiment, a long carbon fiber is used as the fiber, and a cyclic polybutylene terephthalate oligomer is used as the thermoplastic resin cyclic oligomer.

  An end view of the mold 50 used in this embodiment is shown in FIG. The mold 50 used in the present embodiment is a hot press type gold having a movable mold 60 (upper mold) and a fixed mold 70 (lower mold) which are movable in the vertical direction and whose molding surfaces are arranged substantially horizontally. It is a type. At least one of the movable mold 60 and the fixed mold 70 is provided with a heating device (not shown), and the mold can be heated to 180 ° C to 250 ° C. As a heating method, various methods such as a heating medium, for example, a method in which heat such as hot water, steam, oil or the like is transferred to the mold and heated, a method in which the mold is directly heated by electromagnetic induction or a heater, and the like can be used. . Moreover, in order to shorten cycle time arbitrarily, you may provide the cooling device which can cool a type | mold actively. As the cooling device, a method of switching cold water or the like to hot water, steam, oil or the like, a method of switching off electromagnetic induction or a heater, or the like can be used.

  The fixed mold 70 is provided with a plurality of joining object installation portions 71 for installing the joining object 80. The joining object installation portion 71 is formed in a fitting hole in a form inverted with respect to the joining object 80 so that the joining object 80 can be fitted. As shown in FIG. 3, the joining object installation unit 71 is configured so that when the joining object 80 is fitted, the surface 81 of the joining object 80 and the molding surface 72 of the fixed mold 70 are flush with each other. The surface 81 of the joining object 80 may slightly be provided so as to extend from the inner molding surface 72 of the fixed mold 70. By providing in this way, the joining object 80 is slightly embedded in the outer frame 11, and the joining object 80 and the outer frame 11 can be more firmly fixed.

  Now, a joining method (a method for producing the outer frame 11) for joining the sheet-like fiber reinforced thermoplastic resin material 11a and the joining object 80 using the mold 50 configured as described above will be described. To do.

  The joining method according to the present embodiment mainly includes an installation process, a heating process, and a pressurizing process.

  The installation step is a step of installing the joining object 80 and the fiber-reinforced thermoplastic resin material 11a in the mold 50. First, as shown in FIG. 3, the joining object 80 is fitted into the joining object installation portion 71 of the fixed mold 70. Next, as shown in FIG. 4, a sheet-like fiber-reinforced thermoplastic resin material 11 a is installed so as to be laminated on the joining object 80. The number of fiber reinforced thermoplastic resin materials 11a may be one, or a plurality of fiber reinforced thermoplastic resin materials 11a (for example, prepregs) may be laminated as shown in FIG. In addition, since the melting temperature of the cyclic polybutylene terephthalate oligomer is 80 ° C. to 90 ° C. at the stage of the installation process, the fiber reinforced thermoplastic resin material 11a is softened so as to become familiar with the fixed mold 70 in advance. The stationary mold 70 may be heated to about 140 ° C. Further, as will be described later, in order to accelerate the polymerization at this stage, it may be heated to the polymerization temperature.

  The heating process is a process in which the fiber reinforced thermoplastic resin material 11a is molded to a certain form and a part of the thermoplastic resin cyclic oligomer is polymerized. In the installation process, as shown in FIG. 5, the mold 50 is clamped so that an interval wider than the thickness of the finished product is formed in the fiber reinforced thermoplastic resin material without completely clamping. . Since the molds are clamped at intervals wider than the thickness of the finished product, an approximate shape of the product can be formed, but the shape is such that the fiber-reinforced thermoplastic resin material 11a is not compressed. The distance between the molding surface of the movable mold 60 of the molding die 50 and the molding surface of the fixed die 70 is preferably tightened so as to be about 1.3 to 2 times the thickness of the final product. Here, the mold is clamped to increase the heating efficiency and promote polymerization. Therefore, if the heating ability of the mold 50 is high, the mold does not necessarily have to be clamped. Here, the mold clamping is performed at intervals wider than the thickness of the product. The thermoplastic resin cyclic oligomer has a very high fluidity due to heating, so that the mold is clamped to the final product thickness in one step. Then, there is a possibility that the thermoplastic resin cyclic oligomer is shut out from the mold 50 and flows out, and the thermoplastic resin cyclic oligomer may be biased. For this reason, a portion of the thermoplastic resin cyclic oligomer is polymerized in a state where there is a certain amount of clearance or no significant pressure applied, and a viscosity that prevents the thermoplastic resin cyclic oligomer from flowing during mold clamping in the following pressurization process is ensured. It is to do. Preferably, the thermoplastic resin cyclic oligomer is heated to an extent that causes ring-opening polymerization of 10% to 70%. Further, in this state, by increasing the adhesion between the fiber reinforced thermoplastic resin material 11a and the joining object 80, it is possible to further increase the bonding strength when the final product is obtained. For the preheating in the heating step, a value higher than the melting temperature of the thermoplastic resin cyclic oligomer is selected, preferably 100 ° C to 210 ° C, and the heating time is about 30 seconds to 3 minutes, more preferably about 2 to 3 minutes. Do.

  The pressurizing step is a step of forming the fiber reinforced thermoplastic resin material 11a to a final shape and thickness, and polymerizing the thermoplastic resin cyclic oligomer to form a polymer thermoplastic resin. In the pressurizing step, as shown in FIG. 6, by pressurizing and heating so as to be thinner than the original fiber-reinforced thermoplastic resin material 11a, it is molded into the final form and polymerization of the thermoplastic resin cyclic oligomer is performed. To react the entire product to the polymer. In this pressurization process, even if it pressurizes so that it may become thinner than the original thickness of fiber reinforced thermoplastic resin material 11a, a thermoplastic resin cyclic oligomer is partially polymerized by a heating process, and it is in the state where viscosity is high. Therefore, the thermoplastic resin cyclic oligomer can be prevented from flowing out of the mold 50. The pressurizing step is performed at 170 to 210 ° C. for about 4 to 25 minutes. It varies depending on the number of laminated prepregs and thermoplastic resin cyclic oligomers. For example, in the case of 3 laminated sheets, it is heated at 180 ° C. or more for 15 minutes or less, 190 ° C. for 10 minutes or less, and 200 ° C. for about 5 minutes or less. By doing so, it can be preferably polymerized. In addition, when shifting from a heating process to a pressurization process, it becomes possible to shorten the time required for temperature rise by making the set temperature equal.

  When the polymerization reaction is completed, the outer frame as a fiber-reinforced fiber plastic product is completed by cooling to the curing temperature of the polymer and removing the mold. At this time, the cycle time can be shortened by rapid cooling by the cooling device.

  According to the joining method according to the above-described embodiment, a thermoplastic resin cyclic oligomer that is originally unsuitable for use in a press mold is obtained by performing a heating step for increasing the viscosity in advance at the time of molding a product. Can be molded using a fiber reinforced thermoplastic resin material.

  Further, the outer frame produced by the joining method according to the embodiment has a surface in a state where the joining object 80 that cannot be firmly joined with the polybutylene terephthalate by the polymer is not embedded in the fiber reinforced thermoplastic resin material 11a. It can be a fiber reinforced plastic product bonded to the substrate. Therefore, there is no need to re-bond the objects to be joined or to fix them by physical means such as screws or bolts.

  It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that the present invention can be implemented in various modes as long as it belongs to the technical scope of the present invention.

Example 1
As Example 1, a fiber reinforced plastic product produced by the joining method described above was produced, and a tensile adhesive strength test was performed.

As a fiber reinforced plastic product for testing, a fiber reinforced thermoplastic resin material prepared by laminating eight carbon fiber reinforced resin prepregs using a cyclic polybutylene terephthalate oligomer as a matrix (thickness after molding of about 2.0 mm) is prepared. Two stainless steel (SUS303) 12.7 mm square bars were prepared as objects to be joined.
1. Installation process It installed in the metal mold | die (jig) in the state which pinched | interposed the fiber reinforced thermoplastic resin material between the joining objects.
2. Heating step Heating was performed so as to maintain the mold temperature at 100 ° C to 110 ° C and held for 2 minutes.
3. Pressurization process It hold | maintained at 190 degreeC for 10 minute (s), pressurizing with the pressure of 3.0 kg / cm < ² > with a clamp.
4). Cooling step After cooling to the curing temperature of the polymer, it was taken out and used as a product sample.

Five product samples (1 to 5) prepared by the above method were prepared, and the tensile bond strength was measured. The test method was performed based on JIS K6849 (tensile bond strength of adhesive). The test conditions are a test temperature, 23 ° C., and a tensile speed of 1.0 mm / min. The measurement results are shown in Table 1 below and a graph of the measurement results is shown in FIG.

  According to FIG. 7, except for the sample 1, the maximum load is approximately 1100 N or more, the maximum stress is 7 MPa or more, and it was proved that the plastic product has the necessary strength.

(Example 2)
As Example 2, a fiber reinforced plastic product produced by the joining method described above was produced, and a tensile shear bond strength test was performed.

As fiber reinforced plastic products for testing, seven prepregs of carbon fiber reinforced resin 100mm x 35mm with a cyclic polybutylene terephthalate oligomer matrix laminated to a fiber reinforced thermoplastic resin material (approx. 1.6mm thickness after lamination) A plate of stainless steel (SUS304) 100 mm × 25 mm and thickness 1.5 mm was prepared as an object to be joined.
1. Installation Step The fiber reinforced thermoplastic resin material and the object to be joined were installed in a mold (jig) so that a width of 25.0 mm and a length of 12.5 mm overlapped.
2. Heating step Heating was performed so as to maintain the mold temperature at 100 ° C to 110 ° C and held for 2 minutes.
3. Pressurization process It hold | maintained at 190 degreeC for 10 minute (s), pressurizing with the pressure of 3.0 kg / cm < ² > with a clamp.
4). Cooling step After cooling to the curing temperature of the polymer, it was taken out and used as a product sample.

Five product samples (1 to 5) prepared by the above method were prepared, and the tensile bond strength was measured. The test method was performed based on JIS K6850 (adhesive strength tensile shear test). The test conditions are a test temperature, 23 ° C., and a tensile speed of 9.0 MPa / min. The measurement results are shown in Table 2 below and a graph of the measurement results is shown in FIG.

  According to Table 2 and FIG. 8, the maximum load is approximately 4900 N or more, the maximum stress is 15 MPa or more, and it was proved that the plastic product has the necessary strength.

  As shown in the above-described embodiment, it can be used when a product in which various parts are bonded to a fiber reinforced thermoplastic resin material is manufactured.

DESCRIPTION OF SYMBOLS 10 ... Outer frame, 11 ... Outer frame, 11a ... Fiber reinforced thermoplastic resin material, 16 ... Nail hole, 20 ... Upper frame connecting bracket, 30 ... Receiving bracket, 40 ... Front plate connecting bracket, 50 ... Mold, DESCRIPTION OF SYMBOLS 60 ... Movable type | mold, 70 ... Fixed type | mold, 71 ... Joining object installation part, 72 ... Inner side molding surface, 80 ... Joining target object, 81 ... Surface, 100 ... Resin game board

Claims (6)

In a joining method for joining a fiber reinforced thermoplastic resin material and a joining object using a thermoplastic resin cyclic oligomer as a matrix,
An installation step of installing one or two or more sheet-like fiber reinforced thermoplastic resin materials impregnated into a fiber with a thermoplastic resin cyclic oligomer as a matrix and an object to be joined in a press mold that can be heated to a predetermined temperature;
A heating step of heating the fiber-reinforced thermoplastic resin material installed in the mold;
A pressurizing step for shaping the thermoplastic resin cyclic oligomer of the fiber reinforced thermoplastic resin material into a predetermined form by ring-opening polymerization;
A joining method for joining a fiber reinforced thermoplastic resin material and a joining object.   The joining method for joining a fiber reinforced thermoplastic resin material and a joining object according to claim 1, wherein the heating step causes ring-opening polymerization of 10% to 70% of the thermoplastic resin cyclic oligomer.   The said heating process heats for 1 minute-2 minutes, The joining method which joins the fiber reinforced thermoplastic resin material and joining object of Claim 1 or 2 characterized by the above-mentioned.   The said pressurization process clamps the fiber reinforced thermoplastic resin material to the position where it becomes thinner than the state installed in the installation process, The one of Claim 1 to 3 characterized by the above-mentioned. A joining method for joining a fiber-reinforced thermoplastic resin material and an object to be joined. A fiber reinforced thermoplastic resin material having a thermoplastic resin cyclic oligomer as a matrix;
The object to be joined,
A fiber-reinforced plastic product characterized by being bonded.   6. The fiber-reinforced plastic product according to claim 5, wherein the bonding does not include an adhesive component other than the fiber-reinforced thermoplastic resin material.

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