JP2013199016A - Method of producing fiber reinforced plastic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of producing a FRP (Fiber Reinforced Plastic) which improves a quality level of an end face shape of a FRP molded product having a thickness ranging from 10 mm to several ten mm and contributes to the improvement of material yield in a RTM (Resin Transfer Molding) or VaRTM (Vacuum assisted Resin Transfer Molding) method.SOLUTION: A method of producing a fiber reinforced plastic is provided in which a laminate comprising a reinforcing fiber base material is arranged in a mold, resin diffusion media having resin flow resistance lower than that of the reinforced fiber base material extended from a resin injection port are arranged on both surfaces of the laminate, the inside of mold is evacuated through a resin suction medium to reduce the pressure and after that, the resin is injected through the resin diffusion medium into the mold to impregnate the laminated with the resin, In the method, a smooth supporting member is arranged to be along the side wall formed by the thickness of the laminate and a through hole for sucking the resin is provided in the supporting member arranged along the side wall formed by the thickness of the laminate in a position on the opposed side to the resin injection port.

Description

  The present invention relates to a method for producing a fiber reinforced plastic (hereinafter sometimes abbreviated as FRP (abbreviation of Fiber Reinforced Plastic)), and in particular, the end face shape of a thick FRP molded product having a thickness of 10 mm to several tens of mm. The present invention relates to a method for producing FRP that can be improved and contributes to an improvement in material yield.

  The fiber reinforced plastic manufacturing method includes an autoclave molding method in which a prepreg impregnated with a resin in advance to a reinforcing fiber base is heated and pressurized by an autoclave, or a reinforcing fiber base not impregnated with a resin as an upper mold. RTM (Resin Transfer Molding), which is placed in the gap formed by the lower mold and injects the pressurized resin into the gap in a state where the mold is pressurized using a hydraulic press, etc., and then heat cures and molds Law.

  In addition, VaRTM (Vacuum Assisted Resin Transfer Molding) method uses a bagging film instead of the upper mold, depressurizes the inside sealed with the bagging film by vacuum suction, and uses the pressure difference from the atmospheric pressure. This is a method in which a resin is injected into a reinforcing fiber base and then cured by heating and is not practically used as a molding method that can be molded at low cost because it does not use a pressurizing device such as a hydraulic press. Yes.

If it is assumed that the resin impregnation into the reinforcing fiber base in the RTM method or the VaRTM method follows Darcy's law, the flow velocity v (m / s) of the resin is the ease of impregnation of the resin into the reinforcing fiber base (value) Permeability K (m), resin pressure P (Pa), and resin viscosity μ (Pa · s), which are indicators of indicating greater impregnation)
v = −K · ∇P / μ (1)
It is represented by

  That is, the impregnation distance of the resin is proportional to the permeability K (m) of the reinforcing fiber base and the pressure P (Pa) of the resin, and inversely proportional to the viscosity μ (Pa · s) of the resin.

  Therefore, in order to impregnate a thick member using a predetermined reinforcing fiber base (having permeability K (m)), the resin injection pressure P (Pa) is increased or a resin having a low viscosity is used. However, since there is a limit to reducing the viscosity of the resin, it is necessary to substantially increase the injection pressure P (Pa) of the resin.

  In order to increase the resin injection pressure P (Pa), a hydraulic press device or the like can be used to maintain a predetermined gap without opening the mold even when resin is injected into the gap of the mold. It is necessary to press the mold using the pressurizing apparatus.

  On the other hand, since the VaRTM method uses atmospheric pressure, no pressurizing device is required, but the resin injection pressure is limited to atmospheric pressure, so there is a problem that impregnation thickness is limited (Patent Documents 1 and 2). . As a means for solving this problem, a method has been proposed in which a resin diffusion medium or a resin passage is provided on both surfaces of a laminate, and the impregnated thickness is increased by impregnating the resin from both surfaces (Patent Documents 3 and 4). .

  However, both Patent Documents 3 and 4 describe a method for preventing the resin injected from the resin diffusion medium or the resin passage from being discharged through the vacuum suction port by short-passing before the reinforcing fiber base material is impregnated. However, there is a concern that unimpregnation may occur due to the resin being discharged from the vacuum suction port before impregnating the reinforcing fiber base.

  Further, since Patent Documents 3 and 4 do not describe a method for preventing a void from being trapped between resins impregnated from both sides of the laminate, voids are generated in the molded fiber-reinforced plastic. There was concern.

  In Patent Document 5, there is a description on a FRP molding method for preventing the formation of a short path to the resin suction port and eliminating the occurrence of an unimpregnated portion of the resin in the vacuum RTM molding method. There is no description relating to resin injection from one side of the laminate, there is no description relating to resin injection and impregnation from both sides of the laminate to enable impregnation into a thick plate as disclosed in the present invention, and short path Although there was no unimpregnation of the resin due to, there was a concern that the impregnation of the thick plate could not be performed and the unimpregnation occurred.

  Another problem with the above molding method is that it is difficult to obtain good smoothness for the end shape of the molded product. In other words, when molding thick materials (thick plates), the edges of the molded product are uneven due to bagging material such as a film or rubber sheet pressed by atmospheric pressure, and trimming after molding is necessary. Therefore, there is a problem that the material yield is lowered.

  In order to cope with such a problem, it is conceivable to use a concave mold as the lower mold, but in this case, not only the cost of the mold is increased, but it takes a lot of time and labor to demold the molded product. Become. In addition, the pressure is reduced by vacuum suction through the resin diffusion medium before injecting the resin into the mold, but in this step, the side surface of the laminate and the side surface of the mold are not sufficiently adhered. There is a concern that non-impregnation may occur by being discharged from the vacuum suction port before the resin is formed and impregnated into the reinforcing fiber.

JP 2005-527410 A JP 2009-45924 JP 2004-181627 A JP 2006-130733 A JP 2005-271248 A

  The object of the present invention is to solve the above-mentioned problems in the above-mentioned conventional technology, and in particular to improve the quality of the end face shape of a thick FRP molded product having a thickness of 10 mm to several tens of mm, and contribute to the improvement of the material yield. An object of the present invention is to provide a method for manufacturing FRP.

  In order to achieve the above object, a method for producing a fiber reinforced plastic according to the present invention includes a laminate comprising a reinforcing fiber substrate disposed in a mold, and extending from both sides of the laminate from a resin injection port. A resin diffusion medium having a resin flow resistance lower than that of the reinforcing fiber substrate is disposed, and the pressure inside the mold is reduced by vacuum suction through the resin suction medium, and then the resin diffusion medium is inserted into the mold. In the fiber reinforced plastic manufacturing method of injecting resin and impregnating the laminate with resin, a support member is disposed along the side wall formed by the thickness of the laminate, and is positioned on the side opposite to the resin injection port. The support member arranged along the side wall formed by the thickness of the laminated body has a resin suction through hole, and the resin is injected and impregnated from both sides of the laminated body, and the resin suction through Resin from hole It is intended to suction.

  In this way, the method of impregnating the resin from both sides of the laminate can greatly improve the impregnation thickness of the resin as compared with the method of injecting and impregnating the resin from only one surface, and the resin can be added to the laminate. After impregnating in the thickness direction from the resin injection port side to the resin suction port side, the resin impregnated in the thickness direction of the laminate can be sucked from the resin suction through hole, thereby forming a resin short path The occurrence of non-impregnation due to can be suppressed. Also, by placing a smooth support member along the side wall formed by the thickness of the laminate, a bagging material such as a film or a rubber sheet pressed by atmospheric pressure is pressed against the side of the laminate. And the formation of irregularities at the end of the molded product can be suppressed.

  In addition, in this invention, the both surfaces of a laminated body refer to the upper and lower surfaces of the thickness direction of a laminated body. In the description of the present invention, the upper surface of the laminate may be referred to as (front) and the lower surface as (back).

  Here, the resin diffusion medium is not particularly limited as long as it is a material capable of efficiently diffusing and sucking the resin, and can be appropriately selected depending on the reinforcing fiber base used for molding, the resin, and the molding conditions. For example, the form may be mesh, punching, non-woven fabric, etc. Particularly, a mesh having a mesh side length of about 2 to 10 mm is preferable because it has excellent resin diffusion and suction capabilities. If it is smaller than 2 mm, the resin diffusion and suction ability tends to be small, and if it is larger than 10 mm, a bagging film or the like disposed on the resin diffusion medium enters the voids of the mesh and tends to reduce the voids. There is a fear.

  The resin diffusion medium can be made of a resin such as nylon or polyester, or a metal such as stainless steel. It has resistance to the injected resin, heat resistance of the molding temperature, and pressure resistance to the pressure required for molding. If it is, it will not specifically limit. The thickness is preferably 0.5 to 2 mm. If it is smaller than 0.5 mm, the resin diffusing ability tends to be small, and if it is larger than 2 mm, the amount of the resin held in the resin diffusing medium increases, and the yield of the resin may decrease.

  The bagging film is made of a resin such as nylon or polyester, and can be suitably used with a thickness of about 50 to 100 μm. The resistance to the injected resin, the heat resistance of the molding temperature, and the pressure resistance to the pressure of molding. If it has, it will not specifically limit.

  Furthermore, the resin suction through-holes of the support member arranged along the side wall formed by the thickness of the laminate located on the side opposite to the resin injection port join the resin impregnated into the laminate from both sides of the laminate. The resin injected from the resin diffusion medium disposed on both sides of the laminate is impregnated in the thickness direction from both sides of the laminate, and the resin is merged to dispose the resin in the thickness direction. After the impregnation is completed, the resin can be sucked by a resin suction medium, which is preferable because the occurrence of non-impregnation can be suppressed and the resin impregnation thickness can be improved.

  The size of the through hole for resin suction provided in the support member arranged along the side wall formed by the thickness of the laminate located on the side opposite to the resin injection port is 0.1 to 5 mm in height and width Is preferably 0.1 to 50 mm, and the shape of the hole is not particularly limited.

  As the material of the support member on the suction side, it is preferable to use an elastic material such as silicon in order to further improve the sealing performance. In addition, when an elastic material is used, the thickness is preferably 10 mm or more in order to increase rigidity. However, the elastic material is thinned by using the elastic material in combination with a rigid material such as metal or plastic. You can also. Moreover, it is preferable that the support member has such smoothness that the light reflected from the surface is not significantly distorted by visual observation.

  The resin diffusion medium is disposed so as to contact along the side wall formed by the thickness of the laminate positioned on the resin injection port side, so that the injected resin is impregnated in the thickness direction from both sides of the laminate. Further, since the impregnation proceeds from the interlayer on the injection port side, it is possible to prevent a void from being confined between the resins impregnated from both surfaces of the laminate.

  By arranging the resin suction gate so as to include the resin suction through-hole of the support member located on the resin suction side, it is possible to suck the resin through the shortest path and improve the resin yield. . Moreover, since a complicated resin suction mechanism is not required, the working time can be shortened.

  Since the injected resin is impregnated in the thickness direction from both surfaces of the laminate, it is preferable to use a rectangular cross-sectional shape.

  On the surface of the laminate on which the resin diffusion medium is arranged, it is preferable to have a gap where the resin diffusion medium is not arranged between the side wall on which the support member located on the resin suction side is arranged. By providing such a gap, the resin gradually impregnates in the in-plane direction even in a position where the resin diffusion medium is not present, while the resin is impregnated in the thickness direction of the laminate at the position where the resin diffusion medium is disposed. . Furthermore, it is sucked from the resin suction through-hole only after the resin is impregnated into the laminated body in a place where there is no resin diffusion medium. Therefore, the time until the injected resin is sucked from the resin suction medium can be adjusted by adjusting the length of the gap.

  More specifically, even if the resin is impregnated in the thickness direction of the laminate at the place where the resin diffusion medium is disposed, if the resin is not impregnated in the gap portion, the resin is immediately sucked from the through hole for resin suction. Not. In particular, even when an unexpected unimpregnated part occurs during resin injection and impregnation, the gap allows sufficient time for the resin to be sucked in, so the resin impregnates the unimpregnated part. After that, the resin can be sucked from the resin suction medium.

  On the surface of the laminate on which the resin diffusion medium is arranged, the length of the gap in which the resin diffusion medium is not arranged between the side wall on which the support member located on the resin suction side is arranged is 1 to 30 mm. preferable. If it is shorter than 1 mm, the above-mentioned effect can hardly be expected. On the other hand, when it is longer than 30 mm, there is a concern that the gap portion is not impregnated. Moreover, it is preferable that the length of this clearance gap is provided in the substantially constant width over the width direction of a laminated body.

  The resin flow resistance of the resin diffusion medium is preferably low, and the resin flow resistance is preferably 1/3 or less of the resin flow resistance of the reinforcing fiber substrate. If the resin flow medium of the resin diffusion medium is sufficiently lower than the ventilation resistance of the reinforcing fiber base material, it can suppress the vacuum degree inside the laminate, so that even thick laminates are impregnated with resin. It is preferable because it does not impair the performance.

  More preferably, it is 1/10 or less of the resin flow resistance of the reinforcing fiber substrate. Thus, if the flow resistance is low, the diffusibility of the resin injected into the resin diffusion medium in the surface direction of the reinforcing fiber base is sufficiently ensured, and the resin injected into the resin diffusion medium is the reinforcing fiber base. While rapidly diffusing in the direction along the surface, the reinforcing fiber base material is also rapidly impregnated in the thickness direction.

  The resin diffusion medium is preferably removed from the fiber reinforced plastic after molding. Resin diffusion media are often removed because they are not members used as fiber reinforced plastics. By disposing the laminated body so as to be in contact with the side wall formed by the thickness of the laminated body through a peel ply for peeling, etc., it can be easily peeled off and removed after molding.

In addition, the present invention is preferable because a remarkable effect can be expected when the reinforcing fibers are substantially arranged in only one direction. A laminated body in which reinforcing fibers are arranged in only one direction is a laminated body in which reinforcing fibers are laminated at different angles (for example, an 8-layer laminated body in which four layers laminated in the thickness direction are symmetrical: [45 ° / [0 ° / −45 ° / 90 °] _S )), the reinforcing fibers can be arranged more densely, but the resin impregnation tends to be reduced due to the trade-off relationship. For this reason, conventionally, the thickness that can be impregnated with a resin has been greatly limited. On the other hand, if the molding method according to the present invention is used, the effect of the efficient resin impregnation according to the present invention can be exhibited more significantly without generating an unimpregnated portion even in a laminate in which reinforcing fibers are arranged in one direction. This is preferable because it is possible.

  As described above, according to the method for producing a fiber-reinforced plastic of the present invention, it is possible to improve the quality of the end face shape of a thick member having a thickness of 10 mm or more, and to improve the material yield.

In RTM shaping | molding of the fiber reinforced plastics in this invention, it is the figure which showed the cross-sectional schematic diagram of what has arrange | positioned the supporting member to the vacuum suction port side of a laminated body. In RTM shaping | molding of the fiber reinforced plastics in this invention, it is the figure which showed the cross-sectional schematic diagram of what has arrange | positioned the 2nd supporting member to the vacuum suction port side of a laminated body. It is the figure which showed the cross-sectional schematic diagram of what was supported by the material which has rigidity in the vacuum suction port side of a laminated body in the RTM shaping | molding of the fiber reinforced plastics in this invention. It is a cross-sectional schematic diagram using a double-sided mold in the RTM molding of the fiber reinforced plastic in the present invention. It is the figure which showed the cross-sectional schematic diagram of the RTM shaping | molding of the fiber reinforced plastic in a prior art.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the specific embodiments described below.

  Prior to the present invention, a conventional RTM molding technique will be described. FIG. 3 shows a schematic cross-sectional view of a prior art fiber reinforced plastic RTM molding specification.

  In FIG. 3, a resin diffusion medium (back) 3 connected to the resin injection port 2 is disposed on the mold 1, and the laminate 4 is disposed thereon. Further, a resin diffusion medium (table) 5 is disposed on the laminate 4, and a resin suction medium 11 connected to the vacuum suction port 7 is disposed in order to depressurize the inside sealed with the bagging film 9 by vacuum suction. The whole is covered with a bagging film 9, and the space between the mold 1 is sealed with a sealing material 8. If the bagging film 9 is the upper mold of the mold, the inside of the mold formed by the bagging film 9 and the mold 1 is decompressed by vacuum suction from the vacuum suction port 7 using a vacuum pump, etc. Resin is injected from the inlet 2.

  The injected resin begins to impregnate in the thickness direction of the laminate while diffusing into the resin diffusion medium (back) 3 and the resin diffusion medium (front) 5. Since the resin suction medium 11 is disposed at the central portion of the side wall formed by the thickness of the laminated body, the resin impregnated in the thickness direction through the resin diffusion media 3 and 5 is attracted by the resin suction medium 11 in the in-plane direction. The impregnation progresses, and the resin diffusion media 3 and 5 can be impregnated with the resin, and generation of unimpregnated portions can be suppressed.

  However, when the inside of the mold formed by the bagging film 9 and the mold 1 is vacuum-sucked, the bagging film 9 and the mold 1 are formed from the outside of the bagging film 9 due to a pressure difference with the bagging film 9 as a boundary. Although pressure is generated toward the inside of the mold, only the material that is easily deformed by an external force such as the resin diffusion medium 5 and the bagging film 9 is disposed on the side wall formed by the thickness of the laminate. There was a concern that the side wall formed by the thickness of the laminated body was crushed and bent, and irregularities were formed. In addition, when the support member 6 on the suction side is made of an elastic material such as silicon and has a small thickness, the support member is curved by an external force, so that there is a concern that a curved surface is formed on the side wall formed by the thickness of the laminate. It was.

  The present invention overcoming the above-described prior art will be described in detail below. 1-a shows a schematic cross-sectional view of an RTM molding specification of a fiber-reinforced plastic according to an embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same member as the member used by FIG.

  In the present invention, a resin diffusion medium (back) 3 connected to a resin injection port 2 is disposed on a mold 1, and a laminate 4 is disposed thereon. Further, the resin diffusion medium (table) 5 is arranged on the laminate 4 and the smooth support member 6 contacts along the side wall formed by the thickness of the laminate 4 located on the opposite side to the resin injection port 2. Arrange to do. The support member 6 has a through hole X for sucking resin.

  The vacuum suction port 7 is arranged so as to include the resin suction through-hole X, the whole is covered with the bagging film 9, the gap between the bagging film 9 and the mold 1 is sealed with the sealing material 8, and the vacuum suction port 7 is illustrated. Using a vacuum pump or the like, the inside sealed with the bagging film 9 is vacuumed to reduce the pressure.

  Here, the resin suction through-hole X is disposed so as to include an interlayer where the resin impregnated in the laminated body joins from both sides of the laminated body 4.

  In this state, when the resin is injected from the resin injection port 2, the resin begins to be impregnated in the thickness direction of the laminate while diffusing into the resin diffusion medium (back) 3 and the resin diffusion medium (front) 5. Since the resin suction through hole X is disposed at the center of the side wall formed by the thickness of the laminate, the resin impregnated in the thickness direction through the resin diffusion media 3 and 5 is sucked by the resin suction through hole X. The impregnation proceeds in the in-plane direction, and the resin diffusion media 3 and 5 can be impregnated with the resin, and the occurrence of the unimpregnated portion can be suppressed.

  If the reinforcing fiber bases constituting the laminate are the same and the laminate configuration is symmetric with respect to the thickness direction, the merge of the resin impregnated in the thickness direction of the laminate is the center of the thickness. The arrangement of the through holes X is preferably at the thickness center of the laminate.

  On the other hand, for example, if the laminate is configured using a plurality of types of reinforcing fiber bases such as different types of reinforcing fibers, basis weight, and woven structure, and the laminated configuration is not symmetrical with respect to the thickness direction, the resin Since the impregnation speed in the thickness direction of the fiber depends on the impregnation property of each reinforcing fiber base constituting the laminate, it is not necessarily the same. As a result, the location where the resin impregnated in the laminate is merged is not necessarily It does not necessarily become the thickness center of a laminated body.

  Therefore, in the case of such asymmetry, the resin suction medium 7 is checked in advance by the impregnation test or the like where the impregnation of the resin is joined, or impregnation calculation or impregnation simulation using FEM (Finite Element Method) is used. It is preferable to arrange the resin so as to include the layers where the resin merges by confirming the merged portions of the resin estimated based on the analysis results.

  The resin diffusion medium (back) 3 is arranged so as to contact along the side wall formed by the thickness of the laminate 4 located on the resin injection port 2 side. Therefore, the resin diffused in the resin diffusion medium is impregnated in the thickness direction of the laminate, and can also be impregnated along the layers from the side wall formed by the thickness of the laminate 4 located on the resin inlet 2 side. It is possible to prevent the voids from being confined between the resins impregnated from both sides of the laminate 4. Further, since the resin diffusion medium (back) 3 is fixed by the mold 1 and the laminate 4, the resin diffusion medium (back) 3 can be prevented from being broken, and the laminate 4 can be prevented from short-circuiting the resin. The resin can diffuse through the resin diffusion medium (back) 3 to the back side of the laminate, and can be impregnated from the back surface of the laminated body 4 without causing an unimpregnated portion of the resin.

  The resin suction port 7 is disposed so as to include the resin suction through hole X of the support member 6 located on the resin suction side. Therefore, the resin can be sucked by the shortest path, and the yield of the resin can be improved.

  Since the injected resin is impregnated in the thickness direction from both surfaces of the laminate 4, it is preferable to use a rectangular cross section as the laminate 4.

  Even if the resin is impregnated in the thickness direction of the laminated body 4 at the place where the resin diffusion media 3 and 5 are arranged, if the resin is not impregnated in the gap Y, the resin is immediately sucked from the through hole X for sucking the resin. Not. In particular, even when an unexpected unimpregnated portion occurs during resin injection and impregnation, the gap Y can secure a sufficient time until the resin is sucked. After impregnation, the resin can be sucked from the resin suction through hole X.

  That is, in the laminate 4, the impregnation time in the thickness direction of the resin varies due to variations in quality such as the impregnation property and thickness in the thickness direction of the reinforcing fiber base, and the resin injection port 2 of the laminate 4 does not necessarily have a variation. The impregnation is not always completed sequentially from the side. Therefore, it is possible that the resin reaches the resin suction through-hole X and is sucked in a state where an unimpregnated portion is left inside the laminate 4. Here, by providing the gap Y, the resin is impregnated from the resin diffusion media 3 and 5 in the thickness direction of the laminated body and merged, and then the resin is sucked after impregnating only the gap Y in the in-plane direction. Therefore, even when an unimpregnated portion is generated inside the laminated body 4 after the resin has joined unexpectedly, the time until the resin suction through hole X is reached after the resin has joined is utilized. The impregnation of the unimpregnated portion can be completed.

  Moreover, since the curvature of the support member 6 can be suppressed by fixing the support member 6 and the second support member 10 to the side wall formed by the thickness of the laminate 4, the gap Y is short-circuited. Even if there is resin, the resin does not flow between the side wall formed by the thickness of the laminate 4 and the support member 6. In addition, suppressing the bending of the support member 6 can bring the laminate 4 close to an ideal rectangular cross-sectional shape, and can eliminate variations in quality such as impregnation property and thickness in the thickness direction of the laminate 4. The impregnation in the resin thickness direction is stable.

  FIG. 1-b shows a schematic cross-sectional view of a fiber-reinforced plastic RTM molding specification according to another embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same member as the member used by FIG.

  When the support member 6 is made smaller than 10 mm as shown in FIG. 1-b, the second support member 10 made of a rigid material such as metal or plastic is provided on the vacuum suction port side in order to suppress bending deformation from the vacuum pressure. It is preferable to use together.

  FIG. 1-c shows a schematic cross-sectional view of an RTM molding specification of a fiber reinforced plastic according to another embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same member as the member used by FIG.

  When the support member 6 is made smaller than 10 mm as shown in FIG. 1-c, vacuum suction, which is a rigid material such as metal or plastic, over the entire surface of the support member 6 in order to suppress bending deformation from the vacuum pressure. It is preferable to arrange the mouth 7.

  FIG. 2 shows a schematic cross-sectional view of a fiber reinforced plastic RTM molding specification according to another embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same member as the member used by FIG.

  When the double-sided mold is specified as shown in FIG. 2, the molding mold has a resin injection port 2 on the resin diffusion medium 3 side contacting the side wall of the laminate 4 and a resin suction through hole on the support member 6 side. It is preferable to arrange the combined vacuum suction port 7.

Example 1
Toray Industries, Inc. carbon fiber (T620SC-24000) is arranged in one direction, and a carbon fiber base material having a carbon fiber basis weight of 600 g / m ² is used, and the carbon fiber base material is aligned in one direction. A laminate in which 56 sheets were laminated was prepared. This laminated body was arrange | positioned on the shaping | molding die 1 as shown to FIG.

  The resin diffusion medium (front) 5 and the resin diffusion medium (back) 3 were all made of the same polypropylene mesh, and the shape of each gap was 2.5 mm on a side and about 0.6 mm in thickness. The resin diffusion medium (back) 3 and the resin diffusion medium (front) 5 were arranged so that the gap Y shown in FIG.

  The support member 6 having the resin suction through-hole X was disposed over the entire length of the side wall formed by the thickness of the laminate 4 as shown in FIG. 1a, and a silicon material having a Shore A hardness of HS50 was used. In addition, the resin suction through-holes X were arranged at 20 mm intervals with a hole diameter of 3 mm.

  An aluminum channel having a width of 12 mm, a height of 10 mm, and a thickness of 1 mm is used as the resin injection port 2 and the vacuum suction port 6, and the resin injection port 2 is connected to the resin diffusion medium (table) 5 and the resin as shown in FIG. After arranging the vacuum suction port 7 on the diffusion medium (back) 3 so as to include the resin suction through hole X of the support member 6, a nylon tube (not shown) having an outer diameter of 8 mm and an inner diameter of 6 mm. Was inserted into the resin injection port 2 and the vacuum suction port 7.

  Further, from above, the whole was covered with a bagging film 9 and sealed with a molding material 1 using a sealing material 8.

  With the nylon tube inserted into the resin injection port 2 closed, the nylon tube inserted into the vacuum suction port 7 is connected to a vacuum pump (not shown), and the inside sealed with the bagging film 9 is vacuumed. Reduced pressure. The thickness T of the laminate 4 in this state was about 30 mm.

  In a state where the inside of the bagging film 9 is depressurized by vacuum suction, a liquid epoxy resin is injected through a nylon tube inserted into the resin injection port 2 using atmospheric pressure, and a resin diffusion medium (table 5) The laminate 4 was diffused and impregnated using the resin diffusion medium (back) 3.

  The epoxy resin is a resin of a two-component mixture of a main agent and a curing agent, and the viscosity of the resin has an initial viscosity of about 160 mPas and has a tendency to increase by about 2 times after 60 minutes.

  As a result, it was observed that the resin impregnated in the laminate 4 oozed out into the nylon tube inserted into the vacuum suction port 7 about 60 minutes after the start of injection. It is judged that the resin impregnation into the laminate 4 has been completed by the seepage of the resin, the vacuum suction port 7 is closed, the vacuum suction is stopped, the resin injection port 2 is closed, and the resin injection is stopped. did.

  The laminate 4 impregnated with the resin was heated for 24 hours at room temperature and 15 hours at 60 ° C. using an oven with the resin inlet 2 and the vacuum suction port 6 closed to cure the resin. After the resin was completely cured, the molded body was removed from the mold 1.

  As a result of observing the cut surface by cutting the molded body over the entire length at the center in the width direction, it was confirmed that there was no unimpregnated portion. Moreover, the unevenness | corrugation and the curved surface were not formed in the molded object edge part, but the smooth surface was formed.

(Comparative Example 1)
As shown in FIG. 3, a flat plate is used as the mold, and a support member 6 made of a silicon material having a thickness of 2 mm is arranged on the suction side, and the resin suction medium 11 and the airtight material 12 are used. Molded in the same manner as in Example 1.

  As a result of observing the end face of the molded body, it was observed that the resin diffusion medium 5 had an uneven surface due to crushing and a curved surface due to the suction side support member 6 curve.

DESCRIPTION OF SYMBOLS 1 Mold 2 Resin injection port 3, 5 Resin diffusion medium 4 Laminated body 6 Support member 7 Vacuum suction port 8 Sealing material 9 Bagging film 10 Second support member 11 Resin suction medium 12 Airtight material

Claims (10)

  A laminate comprising a reinforcing fiber substrate is disposed in a mold, and a resin diffusion medium having a resin flow resistance lower than that of the reinforcing fiber substrate extending from a resin injection port is disposed on both surfaces of the laminate. A method for producing a fiber reinforced plastic in which after the pressure inside the mold is reduced by vacuum suction through a suction medium, a resin is injected into the mold through the resin diffusion medium, and the laminate is impregnated with the resin. The support member is disposed along the side wall formed by the thickness of the laminate, and the support member disposed along the side wall located on the side opposite to the resin injection port has a through hole for resin suction. A method for producing a fiber-reinforced plastic, characterized in that:   The through holes for resin suction of the support member arranged along the side wall located on the side opposite to the resin injection port are arranged so as to include an interlayer where the resin impregnated in the laminated body merges from both sides of the laminated body. The method for producing a fiber-reinforced plastic according to claim 1.   The method for producing a fiber-reinforced plastic according to claim 1, wherein the resin diffusion medium is disposed so as to contact along the side wall located on the resin injection port side.   The method for producing a fiber reinforced plastic according to any one of claims 1 to 3, wherein a resin suction port is disposed so as to include a through hole for resin suction of the support member positioned on the resin suction side.   The method for producing a fiber-reinforced plastic according to any one of claims 1 to 4, wherein a rectangular shape is used as a cross-sectional shape of the laminate.   On the surface of the laminate on which the resin diffusion medium is arranged, there is a gap where the resin diffusion medium is not arranged between the side wall on which the support member located on the resin suction side is arranged. The manufacturing method of the fiber reinforced plastic in any one of Claims 1-5.   The resin flow resistance of the resin diffusion medium is 1/3 or less of the resin flow resistance of the reinforcing fiber substrate, The method for producing a fiber reinforced plastic according to any one of claims 1 to 6.   The resin flow resistance of the resin diffusion medium is 1/10 or less of the resin flow resistance of the reinforcing fiber substrate, The method for producing a fiber reinforced plastic according to any one of claims 1 to 7.   The method for producing a fiber reinforced plastic according to any one of claims 1 to 8, wherein the resin diffusion medium is removed from the fiber reinforced plastic after molding.   The method for producing a fiber-reinforced plastic according to any one of claims 1 to 9, wherein the laminated body has reinforcing fibers arranged substantially only in one direction.

Images