JP2009045924A - Frp production method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an FRP production method contributing to the improvement of a material yield. <P>SOLUTION: In the FRP production method comprising a process of injecting a resin into a reinforced fiber base material 1 using a resin diffusing medium 2, at least one end of the medium 2 is hermetically sealed and further, the whole or a part of the sealed end is arranged overlapping a part of the reinforced fiber base material. Alternatively, in the above FRP production method, the resin diffusing medium 2 is not disposed on at least one end of the base material 1, but a board is disposed thereon. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing a fiber reinforced plastic (hereinafter referred to as FRP) by a vacuum Resin Transfer Molding (hereinafter referred to as vacuum RTM) molding method, and more particularly to a method for producing FRP that contributes to an improvement in material yield. .

  FRP is a lightweight material that can exhibit high mechanical properties, and is used in various fields. As a typical manufacturing method of FRP, a vacuum RTM molding method is known. In the vacuum RTM molding method, after a reinforcing fiber base is placed in a mold, the cavity in the mold is depressurized, and the resin is put into the cavity using the pressure difference between the reduced pressure in the cavity and the external pressure. In this method, the reinforcing fiber substrate is impregnated with the injected resin, and then the resin is cured, and then demolded after the curing to obtain FRP. The vacuum RTM molding method includes a molding method using upper and lower molds, a method in which a reinforcing fiber base is placed on the lower mold and covered with a bag material such as a film or rubber sheet. is there.

  Patent Document 1 discloses a method in which a reinforcing fiber base material and a resin diffusion medium are arranged in a mold, the whole is covered with a bag material, and the pressure is reduced to inject and cure the resin. However, in this method, when it takes time to impregnate the entire reinforcing fiber substrate, for example, when the reinforcing fiber substrate is thick, the injected resin impregnates the entire reinforcing fiber substrate. Before the operation, the normal resin impregnation path is deviated, and a gap in the cavity such as a wrinkle of the bag material is short-passed to reach the vacuum suction port to cause a problem such as blocking the vacuum suction path. In that case, the suction of the reinforcing fiber base cannot be sufficiently performed, and there is a problem of leaving an unimpregnated portion of the resin.

Patent Documents 2 and 3 disclose a technique for preventing a short path of resin by providing a region having a high flow resistance (a region without a resin diffusion medium) at the end of a reinforcing fiber base as an improved method of the vacuum RTM molding method. Has been. However, the quality of the region is poor, and there is a problem that the material yield decreases because trimming after molding is required.
U.S. Pat. No. 4,902,215 JP 2005-271248 A International Publication No. 03/101708 Pamphlet

  An object of the present invention is to solve the conventional problems and provide a method for producing FRP that contributes to an improvement in material yield.

  In order to achieve the above object, the present invention adopts the following configuration.

  (1) In the FRP manufacturing method including a step of injecting a resin into a reinforcing fiber base using a resin diffusion medium, at least one end of the resin diffusion medium is sealed, and the sealed portion A method for producing FRP in which all or part of the above is overlapped with an end of the reinforcing fiber base.

  (2) The method for producing FRP according to (1), wherein the resin diffusion medium is larger than or substantially the same in shape as the maximum outer shape of the reinforcing fiber substrate.

  (3) The method for producing FRP according to (1) or (2), wherein a film material or a filler is used as means for sealing one end.

  (4) The method for producing FRP according to any one of (1) to (3), wherein a mesh material is used as the resin diffusion medium.

  (5) In the FRP manufacturing method including a step of injecting a resin into a reinforcing fiber base using a resin diffusion medium, the resin diffusion medium is not disposed at at least one end of the reinforcing fiber base; and A method for producing FRP, in which a plate material is disposed at the one end.

  (6) The manufacturing method of FRP as described in (5) whose said board | plate material is the same as the thickness of the said resin diffusion medium.

  (7) The manufacturing method of FRP as described in (1)-(6) which arrange | positions a plate on the said resin diffusion medium.

  By adopting the above-described configuration, the present invention can improve the material yield and obtain a molded product with excellent quality.

  Hereinafter, the present invention will be described in more detail based on embodiments shown in the drawings. The present invention is not limited to the specific embodiments described below.

  FIG. 1 is a schematic view showing an example of a manufacturing apparatus used in the FRP manufacturing method of the present invention, and FIG. 2 is a perspective view showing the inside of the bag material of FIG. 1 and 2, 1 is a reinforcing fiber substrate, 2 is a resin diffusion medium, 4 is a peel ply, 9 is a ventilation material, 8 is an injection port, 10 is a suction port, 12 is a sealing material, 11 is a bag material, Each is arranged on the tool plate 5. The resin pot 6 is connected to the injection port 8 through the injection line 7, and the vacuum pump 14 is connected to the suction port 10 through the suction line 13.

  In the FRP manufacturing method of the present invention, as shown in FIG. 1, first, the reinforcing fiber base 1 is disposed on the tool plate 5. As the reinforcing fiber substrate 1, carbon fiber, glass fiber, aramid fiber, high strength fiber such as PBO (polyparaphenylene benzobisoxazole) fiber, and high elastic modulus fiber are preferable. Among these, carbon fiber is more preferable because it is a reinforcing fiber having high strength and high elastic modulus among these fibers, and therefore, FRP having excellent mechanical properties can be obtained. Further, the cross-sectional shape of the reinforcing fiber base 1 is not particularly limited. For example, in addition to (a) rectangle, (b) C type, (c) I type shown in FIG. 6, L type, Z type, Either T type or hat type may be used.

  Next, the auxiliary molding material necessary for injecting the matrix resin is disposed. The molding auxiliary material here refers to the peel ply 4, the resin diffusion medium 2, the injection port 8, the suction port 10, and the like necessary in the vacuum RTM molding method. On the reinforcing fiber substrate 1, a peel ply 4 is disposed as a molding auxiliary material. The peel ply 4 is preferably a woven fabric made of a fiber such as nylon or polyester so that the resin diffusion medium 2 or the like disposed as a matrix resin flow path does not adhere to the molded product after the matrix resin is cured. It is arranged to do.

  In addition, a matrix resin injection port 8 is provided on one end side of the tool plate 5, and suction is performed for vacuum suction of the inside of the reinforcing fiber base 1 and the bag material 11 on the other end side corresponding to the injection port 8. A mouth 10 is provided. For the inlet 8 and the suction port 10, it is preferable to use an open mold material. For example, an aluminum C channel can be used. Further, the resin pot 6 is installed near the injection port 8 and connected by the injection line 7. The injection line 7 is not particularly limited, but a larger inner diameter is preferable because pressure loss can be reduced.

  Further, a resin diffusion medium 2 that guides the matrix resin from the injection port 8 to the reinforcing fiber base 1 is disposed on the peel ply 4. The resin diffusion medium 2 is not particularly limited as long as the resin flow resistance is lower than that of the reinforcing fiber base 1, but a metal mesh material made of resin such as polypropylene or nylon or metal such as iron or aluminum should be used. Is preferred. The mesh material here has a net-like shape, and means, for example, a mesh cloth, a resin net, a metal net, or the like.

  When a mesh material is used as the resin diffusion medium 2, a resin flow path is secured and the injected matrix resin is strengthened even if the bag material 11 is vacuum-sucked to bring the bag material 11 into close contact with the resin diffusion medium 2. The entire fiber substrate 1 can be guided. In FIG. 1, the peel ply 4 and the resin diffusion medium 2 are disposed on the reinforcing fiber base 1. However, from the viewpoint of impregnation property, surface quality, and the like, the peel ply 4 and the resin are disposed below the reinforcing fiber base 1. A diffusion medium 2 may be disposed. As will be described later, at least one end 3 of the resin diffusion medium 2 used in the present invention is sealed, and all or a part of the sealed portion is overlapped with the end 3 of the reinforcing fiber base 1. However, when the peel ply 4 and the resin diffusion medium 2 are arranged on the reinforcing fiber substrate 1, all or part of the sealed portion is the end portion 3 of the reinforcing fiber substrate 1. When the peel ply 4 and the resin diffusion medium 2 are disposed on the upper portion of the reinforcing fiber base material 1 and the resin diffusion medium 2, all or part of the sealed portion is the end portion 3 of the reinforcing fiber base material 1. It is good to place at the bottom of the.

  Moreover, you may use what uses the plate 17 with a resin flow path which has a groove | channel as shown in FIG. 8 as a resin diffusion medium. The groove 18 for the resin flow path formed in the plate 17 with the resin flow path is not particularly limited as long as the unevenness is not transferred to the molded product, and a unidirectional or mesh-shaped groove can be used. The material of the plate 17 with a resin flow path is preferably made of metal such as aluminum or iron or CFRP from the viewpoint of high durability and reusability.

  As described above, as one of the preferred embodiments of the present invention, at least one end 3 of the resin diffusion medium 2 needs to be sealed. The term “sealed” as used herein means that the resin flowing through the resin diffusion medium 2 is configured not to flow out from the end 3 of the resin diffusion medium 2 to the reinforcing fiber base 1 as shown in FIG. It is. In the FRP manufacturing method of the present invention, all or part of the sealed portion of the resin diffusion medium 2 is arranged so as to overlap the end portion 3 of the reinforcing fiber base 1, so that the resin is the end portion of the resin diffusion medium 2. 3 can be prevented from flowing out into the reinforcing fiber substrate 1 (short path), and the resin can be efficiently impregnated in the thickness direction of the reinforcing fiber substrate 1 to prevent the molded product from being impregnated. can do. In addition, since the end portion 3 of the resin diffusion medium 2 does not substantially have a function as the resin diffusion medium 2, the end of the reinforcing fiber base 1 is the same as when the resin diffusion medium 2 is not present. The flow resistance of the portion 3 is increased, and as a result, it is possible to prevent a short path of the resin.

  The method for sealing the end portion 3 of the resin diffusion medium 2 is not particularly limited as long as the resin is configured not to flow out from the end portion 3 of the resin diffusion medium 2 to the reinforcing fiber base 1. It is preferable to cover and seal the front and back of the end portion 3 of the resin diffusion medium 2 with a sealing material 15 such as a material or a tape. The thickness of the sealing material 15 is preferably such that the level difference is not easily transferred to the molded product. From this viewpoint, it is preferably 0.15 mm or less, and more preferably 0.1 mm or less. The material of the sealing material 15 is not particularly limited as long as it does not melt into the resin, but is preferably made of nylon.

  Another preferred method for sealing the end 3 of the resin diffusion medium 2 is to seal the end with a filler 19 as shown in FIG. The filler here is not particularly limited as long as it does not affect the surface quality of the molded product and the resin does not flow out from the end 3 of the resin diffusion medium 2 to the reinforcing fiber base 1. It is not a thing, but rubber-like stuffing (sealant tape, silicone, etc.) and metal spacers can be used. The filling of the resin diffusion medium with the filler is preferably performed later depending on the size of the reinforcing fiber substrate, but a previously filled material may be used.

  In addition, the one end portion referred to here is an end portion of the resin diffusion medium 2 arranged on the reinforcing fiber base 1 as shown in FIG. 2, and according to the impregnation property to the reinforcing fiber base 1, It is desirable that the suction port side, the side surface side, etc. are appropriately set at the ends and sealed. Further, the size of the portion where the sealed portion of the resin diffusion medium 2 and the end portion 3 of the reinforcing fiber substrate 1 overlap (distance D from the edge of the reinforcing fiber substrate 1 to the end portion of the sealing material 15: FIG. 3-a, see FIG. 3-b) is not particularly limited as long as no unimpregnation occurs in the molded product. However, the end of the reinforcing fiber substrate 1 can be efficiently increased by increasing the flow resistance of the end portion. The thickness is preferably 5 to 35 mm, more preferably 15 to 25 mm from the viewpoint of efficiently impregnating the resin up to the portion 3 and preventing a short path of the resin.

  In addition, the resin diffusion medium 2 in which all or a part of the sealed portion is arranged so as to overlap with the end 3 of the reinforcing fiber base 1 is not smaller than the maximum outer shape of the reinforcing fiber base 1 (that is, It is preferably large or substantially the same shape), and more preferably substantially the same shape as the maximum outer shape. By making the resin diffusion medium 2 larger than or substantially the same as the maximum outer shape of the reinforcing fiber substrate 1, a uniform surface without unevenness can be obtained over the entire surface of the molded product, and the end after molding Since it is not necessary to trim the portion, the material yield can be improved. In addition to these advantages, an improvement in the handling property of the resin diffusion medium 2 and the accuracy of arranging the resin diffusion medium 2 can be expected by making the shape substantially the same as the maximum outer shape.

  Further, another desirable embodiment of the present invention is that, as shown in FIG. 7, the resin diffusion medium 2 is not disposed at least at one end portion 3 of the reinforcing fiber base 1, and the plate material 16 is disposed at the one end portion. Is to arrange.

  The one end referred to here is the end of the reinforcing fiber base 1 as shown in FIG. 7, and the suction port side, the side surface side, etc. are appropriately selected according to the impregnation property of the reinforcing fiber base 1. It is desirable to set it at the end. Further, the size of the portion where the plate material 16 and the end portion 3 of the reinforcing fiber base material 1 overlap (the distance from the edge of the reinforcing fiber base material 1 to the end portion of the plate material 16) must be unimpregnated in the molded product. Although not particularly limited, it is preferable from the viewpoint of efficiently increasing the flow resistance of the end portion and efficiently impregnating the resin up to the end portion 3 of the reinforcing fiber base 1 and preventing a short path of the resin. Is 5 to 35 mm, more preferably 15 to 25 mm.

  If the resin diffusion medium 2 that does not have a sealed portion at the end portion is disposed, the resin flows out from the end portion 3 of the reinforcing fiber base 1 and is not preferable because the resin short-passes. Further, if the plate material 16 is not disposed at the end portion 3, it is not preferable because a step in the thickness of the resin diffusion medium 2 is transferred to the molded product. From this point of view, as another desirable embodiment of the present invention, the resin diffusion medium 2 is not disposed at least at one end portion 3 of the reinforcing fiber base 1, and the plate material 16 is disposed at the one end portion. is there. The thickness of the plate material 16 is not particularly limited as long as the surface of the molded product becomes smooth, but is preferably the same as the thickness of the resin diffusion medium 2 from the point that a uniform pressure is applied to the entire surface. . Specifically, if the thickness of the resin diffusion medium 2 is within a range of ± 0.15 mm, the thickness of the plate material 16 and the thickness of the resin diffusion medium 2 can be evaluated to be the same, and the effects of the present invention can be further exhibited.

  The plate material 16 is not particularly limited as long as the resin flow resistance is higher than that of the resin diffusion medium, but it is made of a metal such as aluminum or iron or a CFRP because of its high durability and reusability. preferable.

  Furthermore, in the FRP manufacturing method according to the present invention, when a plate (made of metal or CFRP) is disposed on the resin diffusion medium 2 as shown in FIG. 9, the smooth product of the plate is transferred to the surface of the molded product. In addition, since the pressure can be uniformly applied to the entire reinforcing fiber substrate, the effect of the present invention (improvement of surface quality) can be further exhibited, such as the influence of the step difference at the end portion can be reduced. .

  On the other hand, the ventilation material 9 is disposed on the suction port 10 side of the reinforcing fiber base material 1 so that a part of the left side is in contact with the reinforcing fiber base material 1 and the right side is connected to the suction port 10 so that the suction can be performed under reduced pressure. Is preferred. The suction port 10 is preferably connected to a vacuum pump 14 through a suction line 13.

  The form of the ventilation material 9 is not particularly limited as long as the suction of the reinforcing fiber base 1 is possible. It is sufficient that at least a part is in contact with the reinforcing fiber substrate 1, and the reinforcing fiber substrate 1 can be disposed over the entire end portion. The material of the ventilation material 9 is not particularly limited, and organic fiber cloth, inorganic fiber cloth, mesh material, and the like can be used. For example, a glass fiber woven fabric or mat material having a low basis weight, or a material having low ventilation resistance such as a synthetic fiber nonwoven fabric is preferable from the viewpoint of performing vacuum suction. Alternatively, a mesh-like sheet material or peel ply used as the resin diffusion medium 2 is a preferable form in terms of low resin diffusion resistance and ventilation resistance. If necessary, a film material is disposed on the ventilation material 9 to prevent the matrix resin from forming a short path and being sucked from the suction port 10 before impregnating the reinforcing fiber base 1. This is also a preferred form. A nylon bagging film or the like can be used as the film material.

  Next, the sealing material 12 is disposed around the auxiliary material for molding, and the whole is covered with the bag material 11. The bag material 11 is not particularly limited as long as the material is highly airtight and flexible. For example, a nylon film material may be used. The sealing material 12 is not particularly limited as long as a desired sealing property is obtained, but it is preferable to use a sealant tape having both sealing property and heat resistance.

  Next, the pressure inside the bag material 11 is reduced from the suction port 10. In order not to leave air in the reinforcing fiber substrate 1, it is preferable to reduce the pressure to 10 torr or less. In addition, in order to prevent air leakage into the bag material 11, the first bag may be further doubled to reduce the pressure in the cavity. Next, the resin in the resin pot 6 flows in from the inlet 8 due to the differential pressure between the atmospheric pressure and the degree of vacuum in the reinforcing fiber base 1. In addition, as resin to be used, thermosetting resins, such as an epoxy, unsaturated polyester, phenol, and vinyl ester, are preferable in terms of moldability and cost.

  When the resin impregnation to the reinforcing fiber base 1 is completed, the line 7 on the injection side is closed. The suction side line 13 may be left open if it is desired to remove volatile gas or increase the fiber volume content of the molded product, but may be closed if surface smoothness is required. good. Next, if necessary, the temperature of the reinforcing fiber base 1 is raised to the curing temperature and cured. A molded product can be obtained by removing the auxiliary molding material after curing.

  And as above-mentioned by this invention, it becomes possible to manufacture FRP with a high material yield.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples.

Example 1
In FIG. 1, first, a reinforcing fiber substrate 1 manufactured by Toray Industries, Inc. (“Torayca” T800SC: 190 g / m ² basis weight), size 300 mm × 300 mm on an aluminum tool plate 5 whose surface is coated with a release material. ) Was arranged in 24 ply. Next, as shown in FIG. 2, as the peel ply 4 (made of nylon) and the resin diffusion medium 2 having releasability on the reinforcing fiber base 1, the end 3 except the inlet side is sealed with a nylon film. The resin diffusion medium 2 made of polypropylene having a pitch of 2.5 mm was disposed so that the sealed portion and the end of the reinforcing fiber base overlap (the distance D from the edge of the reinforcing fiber base 1 to the end of the film was 20 mm). ). Next, on the left side of the resin diffusion medium 2, a resin injection port 8 with an opening of an aluminum C-channel material facing down was disposed. The resin pot 6 was installed near the resin injection port 8 and connected by an injection line 7 made of nylon and having an inner diameter of 6 mm. On the other hand, on the right side of the resin diffusion medium 2, a suction ply in which a peel ply from nylon fiber is disposed as a ventilation material 9 on the reinforcing fiber base 1 and an opening of an aluminum C channel material is placed on the right side of the ventilation material 9. 10 was placed. The suction port 10 was connected to a vacuum pump 14 through a vacuum suction line 13 using a nylon tube having an inner diameter of φ6 mm.

  Next, a sealing material 12 (sealant tape) was placed around the set molding auxiliary material, and the bag material 11 was entirely covered with a nylon film. The inside of the bag material 11 was depressurized to 1 torr from the suction port.

  Next, after the temperature of the reinforcing fiber base 1 was heated to 60 ° C., the resin in the resin pot 6 was injected from the resin injection port 8. As the resin, Toray RTM epoxy resin TR-A36 manufactured by Toray was used. The resin is instantaneously filled into the resin injection port 8 and diffused in the resin diffusion medium 2 in about 5 minutes, and then impregnated in the thickness direction of the reinforcing fiber base 1, and the reinforcing fiber base is added to the ventilation material 9 in 30 minutes. The outflow (arrival) of the resin from the material 1 was confirmed. Since the resin completed the impregnation of the entire reinforcing fiber base 1, the injection line 7 and the suction line 13 were closed. Next, the temperature of the reinforcing fiber substrate 1 was raised to 130 ° C., and the resin in the reinforcing fiber substrate 1 was cured. After confirming the curing of the resin, the molded product was demolded. The demolded molded product was free from resin non-impregnated portions, and a good product having a smooth surface with no irregularities on the entire surface was obtained.

(Comparative Example 1)
The resin diffusion medium 2 was molded under the same conditions as in Example 1 except that the end of the resin diffusion medium 2 was not sealed with a nylon film. When the molded product was removed from the mold, large unimpregnation occurred on the tool surface side.

(Comparative Example 2)
4 is a schematic view showing an example of a manufacturing apparatus used in Comparative Example 2, and FIG. 5 is a perspective view showing the inside of the bag material of FIG. As shown in FIG. 5, the reinforcing fiber base material 1 was molded under the same conditions as in Example 1 except that there was no resin diffusion medium at the end portion 3 (suction port side, both side surface portions side, distance from the edge was 20 mm). Moreover, the size 340 mm x 320 mm of the reinforcing fiber base 1 was used in consideration of the trim at the rear end. When the molded product was removed from the mold, a product that was not impregnated with the resin was obtained. Finally, the end 3 of the step was trimmed to obtain a molded product having a size of 300 × 300 mm. That is, a loss of 40 mm × 20 mm corresponding to the step is generated.

(Example 2)
Molding was performed under the same conditions as in Example 1 except that the resin flow path-equipped plate 17 shown in FIG. In the same manner as in Example 1, the resin flow path was sealed (filled) with a filler (sealant tape) at a distance of 20 mm from the end, and fixed with a polyester tape from above. A non-impregnated resin was obtained, and a good product having a smooth surface with no irregularities on the entire surface was obtained.

(Example 3)
As shown in FIG. 9, molding was performed under the same conditions as in Example 1 except that a plate 20 (made of metal or CFRP) was placed on the resin diffusion medium 2. The demolded molded article was not impregnated, and a molded article having good surface smoothness with no step difference at the end could be obtained. When the unevenness of the surface of the molded product was measured, it was Ra = 12 (Example 1, Ra = 22).

  Although this invention is used for the manufacturing method of FRP of a motor vehicle, an aircraft, a ship, and an industrial use, it is not limited to this.

It is the schematic which shows an example of the manufacturing apparatus used for the manufacturing method of FRP of this invention. It is a perspective view which shows the bag material inside of FIG. It is sectional drawing explaining the edge part (when a resin diffusion medium is larger than the largest external shape of a reinforced fiber base material) of the resin diffusion medium of this invention. It is sectional drawing explaining the edge part (when the resin diffusion medium is substantially the same shape as the largest external shape of a reinforced fiber base material) of the resin diffusion medium of this invention. It is the schematic which shows an example of the manufacturing apparatus used for the manufacturing method of FRP of a comparative example. It is a perspective view which shows the bag material inside of FIG. It is the schematic which shows an example of the cross-sectional shape of a reinforced fiber base material. It is sectional drawing explaining the edge part of the reinforced fiber base material of this invention. It is a perspective view explaining the edge part sealing of the plate with a resin flow path. It is sectional drawing explaining the plate arrange | positioned on the resin diffusion medium of this invention.

Explanation of symbols

1: Reinforced fiber base material 2: Resin diffusion medium 3: End part 4: Peel ply 5: Tool plate 6: Resin pot 7: Injection line 8: Injection port 9: Venting material 10: Suction port 11: Bag material 12: Sealing material 13: suction line 14: vacuum pump 15: sealing material 16: plate material 17: plate 18 with resin flow path 18: groove for resin flow path 19: filler 20: plate D: edge of sealing material from edge of reinforcing fiber base Distance of

Claims (7)

In the method for producing FRP, which includes a step of injecting a resin into a reinforcing fiber base using a resin diffusion medium, the resin diffusion medium is sealed at least at one end, and all of the sealed portion or A method for producing FRP, wherein a part of the FRP is disposed so as to overlap with an end of the reinforcing fiber substrate. The manufacturing method of FRP of Claim 1 whose said resin diffusion medium is larger than the largest external shape of the said reinforced fiber base material, or is substantially the same shape. The method for producing FRP according to claim 1 or 2, wherein a film material or a filler is used as means for sealing the one end. The method for producing FRP according to claim 1, wherein a mesh material is used as the resin diffusion medium. In the FRP manufacturing method including a step of injecting a resin into a reinforcing fiber base using a resin diffusion medium, the resin diffusion medium is not disposed at at least one end of the reinforcing fiber base, and the one end Manufacturing method of FRP which arrange | positions board | plate material in the. The manufacturing method of FRP of Claim 5 whose said board | plate material is the same as the thickness of the said resin diffusion medium. The manufacturing method of FRP of Claims 1-6 which arrange | positions a plate on the said resin diffusion medium.

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