JP2007261014A - Fiber-reinforced resin plate and manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fiber-reinforced resin plate of a good and thick molding, which is impregnated with and diffuses a resin efficiently and has no or almost no defect such as unimpregnation, a void, or a pit, and a manufacturing method. <P>SOLUTION: The fiber-reinforced resin plate which is formed by a fiber laminate with fiber-reinforced layers and impregnation auxiliary layers being laminated and integrated alternately and in which the impregnation auxiliary layer is a base material promoting the impregnation of a resin impregnated with a thermosetting resin is composed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention impregnates the resin in the direction parallel to each base material from the side to the base material in which the fiber reinforced base material and the impregnation auxiliary base material are alternately laminated. The present invention relates to a method for producing a fiber reinforced resin plate and a fiber reinforced resin plate capable of obtaining a thick molded article having no crack.

  The resin transfer molding method is a kind of molding method using a thermosetting resin, and a molded product (composite material) is obtained by injecting a resin into a mold cavity and curing it. As the mold for injecting the resin, a highly rigid mold is generally used. When the purpose is to produce a large molded article, molding is performed by replacing a part of the mold with a flexible bagging film.

  To mold a composite material using the resin transfer molding method, after laminating a molding material such as a fiber reinforced base material on a mold, the resin is injected into the mold cavity to impregnate the fiber reinforced base material with the resin. Harden.

  Since resin injection does not apply excessive pressure to the mold or the molded product, a low-pressure sealing molding method using vacuum assist is used. When the resin is injected into the cavity formed by the mold using this method, the resin is easily injected because the mold is not deformed. However, when the fiber reinforced substrate is sealed with the mold and the bagging film, the pressure between the mold and the bagging film reduces the pressure between the bagging film and the resin flow path. Since it is blocked, impregnation and diffusion of the resin are hindered. If impregnation and diffusion of the resin are hindered, it takes a long time to inject the resin, and defects such as non-impregnation, voids and pits occur. This defect becomes more prominent as the molded product becomes larger.

  For this reason, when manufacturing a composite material using a bagging film, a resin diffusion medium (media) is usually used so that the resin is easily diffused. The resin diffusion medium is a mesh-like sheet. After the fiber reinforced base material is laminated on the mold, the resin diffusion medium is laminated on the fiber reinforced base material. The resin diffusion medium is necessary for efficiently diffusing the resin. However, depending on the lamination method, it may cause defects such as non-impregnation, voids, pits, and the like.

  In addition, conventional techniques for improving resin impregnation and diffusion without using a resin diffusion medium include providing grooves on the surface of a core material made of polyurethane or other balsa material, or subdividing the core material. There is a resin transfer molding method (see, for example, Patent Documents 1 and 2). This method uses a plurality of parts in which a core material having a groove network coated with a fiber reinforced base material is used to arrange the parts into the shape of a desired molded product, and then a resin is supplied to the core material groove to form a fiber reinforced base material. It is impregnated and integrated to obtain a final product.

However, with this method, it is difficult to reduce the thickness of the core material to 3 mm or less, and it is very difficult to form a groove on the surface of the core material having a thickness of 3 mm or less.
JP 2000-501659 A (page 21, FIG. 1) JP-T-2001-510748 (page 11, paragraph number [0017])

  The object of the present invention is to solve the above-mentioned problems of the prior art, and the resin is efficiently impregnated and diffused, and there are no defects such as non-impregnation, voids and pits, and there is almost no defect. An object of the present invention is to provide a fiber reinforced resin plate and a manufacturing method for a thick molded article.

  Another object of the present invention is to obtain a molded product having a thinner thickness than a method using a grooved core material, and further forming a molding material having the same thickness from a molded product using a fiber reinforced base material. An object of the present invention is to provide a fiber-reinforced resin plate and a production method capable of producing a molded product having comparable physical performance at a low cost.

The present invention for solving the above-described problems employs the following configuration. That is,
(1) The fiber reinforced layer and the impregnation auxiliary layer are formed by a fiber laminated body in which the fiber reinforced layer and the impregnation auxiliary layer are alternately laminated and integrated, and the base material for promoting the resin impregnation is impregnated with the thermosetting resin. A fiber-reinforced resin plate characterized by being

  (2) The fiber reinforced resin plate according to (1), wherein the fiber reinforced layer has a thickness of 1 to 10 mm, and the impregnation auxiliary layer has a thickness of 1.0 mm or less.

  (3) The fiber reinforced resin plate according to (1) or (2), wherein the fiber volume content of the reinforcing fibers constituting the fiber reinforced layer is 40 to 70%.

  (4) The fiber reinforcement according to any one of (1) to (3) above, wherein the fiber laminate in which the fiber reinforcement layers and the impregnation auxiliary layers are alternately laminated has a thickness of 5 to 60 mm. Resin plate.

  (5) The fiber reinforcing layer having a fiber volume content of 40 to 70% and the impregnation auxiliary layer having a fiber volume content of 10 to 30% form a layer in the thickness direction, and the thickness ratio occupied by the fiber reinforcing layer is 5 to 5. 95. The fiber-reinforced resin plate according to any one of (1) to (4), wherein the total thickness of the fiber-reinforced layer is 3 to 57 mm.

  (6) Fiber reinforcement characterized by impregnating a base material in which a fiber reinforced base material and an impregnation auxiliary base material are alternately laminated with liquid thermosetting resin under vacuum in a direction parallel to each base material from the side and curing. Manufacturing method of resin plate.

    (7) The method for producing a fiber-reinforced resin plate according to (6) above, wherein the fiber volume ratio of the substrate used for the impregnation auxiliary substrate is 10 to 30%.

  (8) The fiber according to any one of (6) and (7), wherein a base material for inducing the resin is provided to each of the impregnation auxiliary base materials on the injection-side end face of the thermosetting resin. A method for producing a reinforced resin plate.

  (9) The base material for inducing the resin to the impregnation auxiliary base material is obtained by cutting the impregnation auxiliary base material longer in the injection direction of the thermosetting resin than the fiber reinforced base material and laminating so as to protrude from the end face. The manufacturing method of the fiber reinforced resin board as described in said (8).

  (10) The method for producing a fiber-reinforced resin plate according to any one of (6) to (9), wherein the resin has a viscosity of 1 to 4 Pa · s during injection.

  According to the present invention, since a continuous strand mat (hereinafter sometimes abbreviated as CSM) for uniformly impregnating and diffusing the resin is used between the layers, the resin impregnation and diffusion are good, unimpregnated, It is possible to provide a good thick article having no or almost no defects such as voids and pits. Further, by setting the thickness of the CSM to 1 mm or less, it is possible to provide a thick article without reducing the fiber volume content.

  Hereinafter, the present invention will be described in more detail based on embodiments shown in the drawings.

  FIG. 1 is a side sectional view showing an embodiment of a method for producing a fiber-reinforced resin plate according to the present invention, FIG. 2 is a top view of FIG. 1, and FIG. 3 is a fiber-reinforced resin according to the present invention. It is a general | schematic expansion | deployment perspective view which shows an example of the fiber laminated body used for the manufacturing method of a resin board.

  As shown in FIGS. 1 and 2, the fiber-reinforced resin plate of the present invention has fiber-reinforced substrates 3a, 3b, 3c,... 3f and impregnation auxiliary substrates 4a, 4b, 4c,. It consists of a laminated fiber laminate 1.

  The fiber reinforced layer constituting the fiber reinforced resin plate of the present invention obtained by impregnating the fiber reinforced substrate with resin by the production method described later has a thickness of 1 to 10 mm, and the thickness of the impregnation auxiliary layer is 1.0 mm or less. Preferably there is.

  The fiber reinforced substrate 3 is a substrate made of reinforced fibers. As a material of this fiber reinforced base material, the material used for normal fiber reinforced base materials, such as carbon fiber, glass fiber, aramid fiber, boron fiber, and metal fiber, can be used. Among these, carbon fiber, glass fiber, and aramid fiber are preferable.

  As a material of the fiber reinforced base material, any woven material may be used, but the fiber reinforced base materials are preferably used in combination so as to be symmetrical with each other. By making the fiber-reinforced base material symmetrical with respect to the impregnation auxiliary base material, it is possible to prevent warping of the molded product. Examples of the woven fabric that can be plane-symmetric with respect to the impregnation assisting substrate include a plain woven fabric, a twill woven fabric, a satin woven fabric, a unidirectional woven fabric, and a multiaxial woven fabric.

  The unidirectional woven fabric refers to a woven fabric in which reinforcing fiber bundles (strands) arranged in parallel are knitted with nylon yarn, polyester yarn, glass fiber or the like. A polyaxial woven fabric refers to a woven fabric in which sheet-like reinforcing fibers aligned in one direction are laminated at different angles and knitted with nylon yarn, polyester yarn, glass fiber or the like.

  The thickness of the fiber reinforced layer in the present invention obtained by impregnating the fiber reinforced base material with a resin by the production method described later is preferably 1 to 10 mm, and is appropriately selected depending on the use of the molded product. 2-9 mm is preferable.

  For the purpose of improving the surface quality of the molded product, fiber reinforced substrates 2a and 2b having a thickness of less than 1.0 mm may be used for the outermost layer portion of the fiber reinforced substrate 3. For example, a plain-woven carbon fiber reinforced fabric or a glass fiber reinforced fabric.

  The impregnation auxiliary base material 4 constituting the fiber laminate 1 serves as a base material that promotes resin impregnation when resin is injected in resin transfer molding. As the base material for promoting the impregnation of the resin, any resin can be used without limitation as long as the speed at which the resin is impregnated from the fiber reinforced base material is equal or higher.

  As a base material for promoting the impregnation of the resin constituting the impregnation auxiliary base material 4 in the present invention, continuous fiber bundles (strands) are dispersed in a random direction and laminated to a uniform thickness, and a fiber bundle using a binder. It is composed of a sheet-like material bonded together, and generally a continuous strand mat (CSM) can be used.

  As the material for the impregnation auxiliary base material, materials used for ordinary fiber reinforced base materials such as carbon fiber, glass fiber, aramid fiber, boron fiber, and metal fiber can be used. Among these, carbon fiber, glass fiber, and aramid fiber are preferable.

  The thickness of the impregnation auxiliary layer in the present invention obtained by impregnating the impregnation auxiliary base material with the resin by the production method described below is preferably 1.0 mm or less, and more preferably 0.3 to 0.6 mm. . When the thickness exceeds 1.0 mm, the amount of resin required increases, and the weight of the molded product increases.

Further, it is preferable that the basis weight of the impregnated auxiliary substrate is 250~500g / m ^2. The impregnation auxiliary base material of less than 250 g / m ² is difficult to produce, and if it exceeds 500 g / m ² , the resin diffusion rate tends to decrease.

  The fiber volume fraction Vf of the impregnation assisting substrate used in the present invention is preferably 10 to 30%, and the fiber volume fraction Vf of the fiber reinforced substrate is preferably 40 to 70%. By setting each fiber volume ratio within this range, the resin injected into the fiber laminate penetrates the impregnation auxiliary base material and diffuses throughout the fiber laminate in a short time.

  The fiber volume fraction of the impregnation auxiliary base material and the fiber reinforced base material in the present invention represents the volume ratio occupied by fibers in each base material, and the thickness (actual measurement value) and the basis weight of each base material (actual measurement) Value) and fiber density (catalog value or actual measurement value). Specifically, the basis weight is calculated from an average value by cutting out five 100 mm square samples from each base material, measuring each weight with an electronic balance. Thickness is measured by applying a flat plate (aluminum plate, etc.) having a thickness of 2 mm to both surfaces of each substrate, measuring 5 points each based on JISB7502, and calculating the average value of the values obtained by subtracting the thickness of the flat plate. Thickness. The fiber volume ratio is calculated from these values and the fiber density. The density of the fiber may be a catalog value, or may be measured using Archimedes method or the like using a solvent in which the fiber to be measured does not swell. Although a fiber reinforced base material laminated on both surfaces of the impregnation auxiliary base material may be used, the fiber laminate may be laminated with one fiber reinforced base material on each side of the impregnation auxiliary base material, A fiber reinforced base material may be laminated.

  The thickness of the fiber reinforced substrate laminated on the impregnation auxiliary substrate is preferably 1 to 10 mm per side.

  Hereinafter, the fiber-reinforced resin plate molding method of the present invention will be described with reference to FIGS. 1 and 2.

  The fiber reinforced base material 3 constituting the fiber reinforced layer and the impregnation auxiliary base material 4 constituting the impregnation auxiliary layer are cut into predetermined dimensions. At this time, as shown in FIG. 1, if the impregnation assisting base material is cut long in the resin impregnation direction, the work efficiency in the subsequent process is good.

  First, the fiber reinforced substrate 2b is laminated on the mold 11 subjected to the mold release treatment. Subsequently, the impregnation auxiliary base material 4g is laminated on the fiber reinforced base material 2b so as to protrude to the resin injection side, the fiber reinforced base material 3f is further laminated thereon, and the impregnation auxiliary base material 4f is further formed thereon. Lamination is performed so as to protrude to the resin injection side, and thereafter, this operation is sequentially repeated to form the fiber laminate 1. Here, the impregnation assisting base material 4 f that protrudes from the fiber laminate 1 to the resin injection side serves as a device for guiding the resin to the fiber laminate 1. Next, the pressure plate 5 is disposed on the fiber laminate 1, and the resin injection port line 7 is installed on the impregnation assisting base material protruding from the resin injection side. If the length of the impregnation auxiliary base material is insufficient, the same material is additionally laminated. On the other hand, a peel ply and a bleeder 6 are appropriately disposed on the exhaust (evacuation) side of the fiber laminate 1, and a vacuum suction port line 8 is installed.

  A bagging film 10 is disposed so as to cover the fiber laminate 1, the resin inlet line 7, and the vacuum suction line 8, and a peripheral edge of the bagging film 10 is formed with a mold 11 using a sealant 9. Airtightly seal and seal. A well-known sealant and a sealing method using the sealant can be used.

  After sealing the fiber laminate 1 using the bagging film 10, the gas between the mold 11 and the bagging film 10 is exhausted and decompressed. Next, a resin is injected from a resin injection port line 7 formed at one end in the bagging film 10. The injected resin passes through the impregnation auxiliary base material 4 in the direction parallel to each layer while moving toward the vacuum suction port line 8 formed at the other end opposite to the resin injection port line 7 in the bagging film 10. Impregnate and diffuse throughout the fiber laminate.

  Since the resin can be injected at a low pressure, a low-pressure sealing molding method using vacuum assist can be used if necessary.

  Thereafter, the resin impregnated in the entire fiber laminate 1 and the resin covering the surface of the fiber laminate are cured at room temperature.

  When heating is necessary for curing the resin, the fiber laminate 1, the mold 11 and the bagging film 10 are heated using an oven or the like. When heating, it is preferable to exhaust the gas between the mold 11 and the bagging film 10.

  In addition, after impregnating the impregnation auxiliary base material with the resin, in order to efficiently impregnate the entire fiber laminate, the pressure may be applied from the outside of the bagging film 10 toward the fiber laminate 1.

  Moreover, a peel ply or the like may be stacked on the fiber laminate 1 as necessary for the purpose of improving the releasability when taking out the molded product.

  As the resin used in the resin transfer molding method of the present invention, a thermosetting resin usually used for the production of a molded product can be used. Specifically, epoxy resin, unsaturated polyester resin, phenol resin, melamine resin, polyurethane resin, silicone resin, maleimide resin, vinyl ester resin, cyanate ester resin, resin obtained by prepolymerizing maleimide resin and cyanate ester resin, etc. In the present invention, a mixture of these resins can also be used. When a fiber reinforced composite material is used, an epoxy resin composition and a vinyl ester resin composition excellent in heat resistance, elastic modulus, and chemical resistance are preferable. These thermosetting resins may contain a curing agent, a curing accelerator and the like.

  The thermosetting resin preferably has a resin viscosity of 1 to 4 Pa · s at the time of injection.

  In the present invention, a CSM excellent in resin diffusion is used as a resin diffusion medium, and this resin diffusion medium is integrally formed with a fiber reinforced base material to obtain a molded product. Conventionally, as a method of increasing the resin diffusion rate by using a material that becomes a part of a molded product by performing integral molding, a method of inserting a core material having grooves or through holes into a fiber reinforced base material has been used. . However, it is difficult for the core material to have a thickness of 3 mm or less, and it is very difficult to form a groove on the surface of the core material having a thickness of 3 mm or less.

  Generally, when a composite material is manufactured using a bagging film, a resin diffusion medium (media) is usually used so that the resin is easily diffused. The resin diffusion medium is a mesh-like sheet. After the fiber reinforced base material is laminated on the mold, the resin diffusion medium is laminated on the fiber reinforced base material. The resin diffusion medium is necessary for efficiently diffusing the resin. However, depending on the lamination method, it may cause defects such as non-impregnation, voids, pits, and the like.

  According to the present invention, the impregnation auxiliary base material is disposed uniformly or randomly between the layers of the fiber reinforced base material, and each impregnation auxiliary base material is cut long in the injection direction to prevent non-uniform flow of resin such as a shortcut. It is possible to obtain a molded article having a thickness of 5 to 60 mm with no or almost no defects such as impregnation, voids and pits. In the molded product, the fiber reinforced base material is completely impregnated with the resin through the impregnation auxiliary base material, the fiber reinforcing layer having a fiber volume content of 40 to 70%, and the impregnation auxiliary having a fiber volume content of 10 to 30%. It is preferable that the layers form a layer in the thickness direction, the thickness ratio occupied by the fiber reinforced layer is 5 to 95%, and the total thickness of the fiber reinforced layer is 3 to 57 mm.

  Here, the measurement of the fiber volume content of each layer is performed as follows.

When the fiber volume ratio before molding of the base material of each layer (before resin impregnation) and the number of base materials in each layer are known by the above-described measurement before molding, the thickness of each layer of the molded body is a thickness described later. By the measuring method, it can obtain | require by the following Formula from the measured thickness.
(Fiber volume ratio of base material) x (thickness of base material) x (number of base materials included in layer) ÷ (thickness of layer)
When the fiber volume ratio before molding, the thickness of the base material, and the number of base materials in each layer are unknown, the resin is thermally decomposed at 500 to 550 ° C., and each base material is taken out. The fiber volume ratio and the thickness of the base material are obtained by the volume ratio measuring method, and calculated using the above formula.

  The thickness of each layer of the molded body used in the previous fiber volume content measurement is determined by the following measurement method.

  (1) The periphery of the rectangular shaped body is cut off with a width of at least 30% of the thickness of the central portion of the shaped body.

(2) The thickness is measured at the eight corners of the rectangular corner and the central part of each side, and the average is obtained (n = 1 at each point)
(3) Thickness is measured by mirror-polishing the measured part (rough polishing: paper file → finish: buff + abrasive), magnified 10 times with an optical microscope, and measured with a scale of 1 mm on the minimum scale. Measure to 1 mm.

The thickness ratio is obtained by dividing the total thickness of each base material layer (fiber reinforced layer, impregnation auxiliary layer, etc.) obtained in the above (1) to (3) by the total thickness of the molded body.

  Hereinafter, the present invention will be described more specifically with reference to examples.

Example 1
Carbon fiber woven fabric (two directions, plain weave) CO 6343B (weight per unit area: 200 g / m ² ) manufactured by Toray Industries, Inc. was cut to 25 × 50 cm and laminated on the release-treated glass plate in the [0/90] direction (see FIG. 2 of 2). On top of that, one sheet of CSM M8609 300 1000 (weight per unit area 300 g / m ² ) manufactured by Asahi Glass Fiber Co., Ltd. cut to 25 × 70 cm is laminated (4 g in FIG. 2), and further on it is 25 × 50 cm in the [0] direction. laminating 30 sheets of cut was manufactured by Toray Industries, Inc. carbon fiber fabric (unidirectional fabrics) BT-7-30 (basis weight 300 g / m ²⁾ (3f in Fig. 2) were further laminated the CSM thereon (FIG. 2 4f). This series of laminations was repeated to obtain a fiber laminate having the structure shown in FIGS. Thereafter, the pressure plate 5 is placed on the fiber laminate, the sealant tape, the peel ply / bleeder 6, the resin inlet line 7, the vacuum suction line 8, the resin injection hose and the resin discharge hose are arranged on the glass plate, and the laminated material The whole was covered with a bagging film 10 and sealed. The mouth of the resin injection hose was closed, the resin discharge hose was evacuated with a vacuum pump, and the inside of the bag was evacuated.
Thereafter, a mixed liquid obtained by mixing 100 parts by mass of unsaturated polyester resin “Rigolac (registered trademark)” RI-230FRM (manufactured by Showa Polymer Co., Ltd.) and 1 part by mass of “Permec (registered trademark)” N (manufactured by NOF Corporation) It injected into the laminated material from the resin injection hose and cured the mixed solution to obtain the product of the present invention. The thickness of the obtained molded product was 54.28 mmt, and the unidirectional fabric difficult to impregnate was uniformly impregnated with the resin, and it was a good product free from resin chipping and defects (voids and pits).
Similarly, as a comparative product, one carbon fiber woven fabric (two-way, plain weave) CO6343B (weight per unit area: 200 g / m ² ) manufactured by Toray Industries, Inc. is laminated, and a carbon fiber woven fabric (one-way woven fabric) CK6223CL (toray) A laminate of 30 sheets having a basis weight of 200 g / m ² ) was further laminated on top of which CO6343B was formed, and molding was carried out using a spacer net TSX-312N made by Tokyo Polymer as a medium. Table 1 shows the results of the product of the present invention and the comparative product.

  The product of the present invention was a good product that was uniformly impregnated with resin and free from resin chipping and defects (voids and pits) despite the use of a unidirectional fabric that was difficult to impregnate.

It is side surface sectional drawing which shows one embodiment of the manufacturing method of the fiber reinforced resin which concerns on this invention. FIG. 2 is a top view of FIG. 1. It is a general | schematic expansion | deployment perspective view which shows an example of the fiber laminated body used for the manufacturing method of the fiber reinforced resin board which concerns on this invention.

Explanation of symbols

1: Fiber laminates 2a, 2b: Fiber reinforced base material 3: Fiber reinforced base material 4: Impregnation auxiliary base material 5: Pressure plate 6: Peel ply / bleeder 7: Resin injection port line 8: Vacuum suction port line 9: Sealant 10 : Bagging film 11: Mold

Claims (10)

The fiber reinforced layer and the auxiliary impregnation layer are formed of a fiber laminate in which the auxiliary layers are alternately laminated and integrated, and the impregnation auxiliary layer is obtained by impregnating a base material that promotes resin impregnation with a thermosetting resin. A fiber-reinforced resin plate characterized by being. The fiber-reinforced resin plate according to claim 1, wherein the fiber-reinforced layer has a thickness of 1 to 10 mm, and the impregnation auxiliary layer has a thickness of 1.0 mm or less. The fiber-reinforced resin plate according to claim 1 or 2, wherein the fiber volume content of the reinforcing fibers constituting the fiber-reinforced layer is 40 to 70%. The fiber reinforced resin plate according to any one of claims 1 to 3, wherein a thickness of the fiber laminate in which the fiber reinforced layers and the auxiliary impregnation layers are alternately laminated is 5 to 60 mm. A fiber reinforcing layer having a fiber volume content of 40 to 70% and an impregnation auxiliary layer having a fiber volume content of 10 to 30% form a layer in the thickness direction, and the thickness ratio occupied by the fiber reinforcing layer is 50 to 95%. The total thickness of a fiber reinforcement layer is 3-57 mm, The fiber reinforcement resin board in any one of Claims 1-4 characterized by the above-mentioned. A fiber reinforced resin plate comprising a substrate in which a fiber reinforced base material and an impregnation auxiliary base material are alternately laminated, and a liquid thermosetting resin under vacuum being impregnated in a direction parallel to each base material from the side and cured. Production method. The fiber volume percentage of the base material used for the said impregnation auxiliary base material is 10 to 30%, The manufacturing method of the fiber reinforced resin board of Claim 6 characterized by the above-mentioned. 8. The method for producing a fiber-reinforced resin plate according to claim 6, wherein a base material for inducing the resin to each of the impregnation auxiliary base materials is provided on the end surface on the injection side of the thermosetting resin. . The base material for inducing the resin to the laminate is obtained by cutting the impregnation auxiliary base material longer in the direction of the thermosetting resin inlet line than the fiber reinforced base material and laminating so as to protrude from the end face. The manufacturing method of the fiber reinforced resin board of Claim 8. The method for producing a fiber-reinforced resin plate according to any one of claims 6 to 9, wherein the viscosity of the resin at the time of pouring is 1 to 4 Pa · s.

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