JP6161559B2 - MANUFACTURING METHOD FOR FIBER-REINFORCED COMPOSITE, MEMBER FOR TRANSPORTATION DEVICE, AND MEMBER FOR AUTOMOBILE - Google Patents

Description

  The present invention relates to a method for producing a fiber-reinforced composite, a transport device constituent member, and an automobile member.

  In recent years, fiber-reinforced synthetic resins reinforced with fibers are lightweight and have high mechanical strength, so they are used in fields where high mechanical strength and light weight are required, such as the automotive field, ship field, and aircraft field. Is expanding. Among them, in automotive applications, it is required to have mechanical strength while satisfying lightness.

  In order to satisfy the above requirements, a fiber reinforced composite has been proposed in which a foam molded body is used as a core material and a fiber reinforced plastic layer is laminated and integrated on the surface of the core material. This fiber-reinforced composite can be used for members such as automobile floor panels, roofs, bonnets, fenders, and undercovers. When used for these members, mechanical strength is not sufficient only by laminating and integrating a fiber reinforced plastic layer on the surface of a core material made of a foam-molded product, and higher mechanical strength is required.

  For example, Patent Document 1 discloses a step of forming a first gel coat layer on the surface of a molded lower mold, and a groove for first resin diffusion on the entire surface of the first gel coat layer opposite to the molded lower mold. A step of forming, a step of disposing the first reinforcing fiber base material in the lower mold toward the first gel coat layer in a state where the first reinforcing fiber base material and the core material are stacked, and the core A step of attaching an encapsulating film to the lower mold so as to enclose the material and the first reinforcing fiber base, a step of reducing the pressure by sucking air inside the encapsulating film from an air suction port, A liquid resin is injected into the encapsulating film from a resin injection port, and the liquid resin is caused to flow through the first resin diffusion groove and diffuse in the surface direction of the first reinforcing fiber base. Impregnating and curing the first reinforcing fiber base. A method for producing a fiber reinforced plastic structure is disclosed, and a resin diffusion groove is formed on the surface of the first gel coat layer formed on the surface of the molding lower mold, thereby forming a resin diffusion groove formed on the surface of the core material. A manufacturing method of a fiber-reinforced plastic structure excellent in productivity, in which no groove is required, is disclosed.

JP 2013-67071 A

  However, the fiber reinforced plastic structure manufactured by the method for manufacturing a fiber reinforced plastic structure described in Patent Document 1 has a fiber reinforced plastic structure obtained by transferring a groove for resin diffusion to the surface of the fiber reinforced plastic layer. There is a problem that the appearance of the body is low.

  Moreover, in the manufacturing method of the fiber reinforced plastic structure of patent document 1, although the groove | channel for resin diffusion is formed in the surface of a 1st gel coat layer, it is aiming at the spreading | diffusion of liquid resin to the 1st reinforced fiber base material. The supply degree of the liquid resin to the first reinforcing fiber base changes between the portion where the groove for resin diffusion is formed and the portion where the groove is not formed, so that the first reinforcing fiber base is impregnated with the resin. May become non-uniform, resulting in a problem that the mechanical strength of the resulting fiber-reinforced plastic structure is lowered.

  The present invention relates to a method for producing a fiber reinforced composite having excellent appearance, mechanical strength and light weight, and a transportation equipment configuration using the fiber reinforced composite produced by the method for producing the fiber reinforced composite. A member and an automotive member are provided.

  The method for producing a fiber-reinforced composite of the present invention includes a laminating step of laminating reinforcing fibers on the surface of a foamed molded body to produce a laminated body, supplying a synthetic resin to the reinforcing fibers of the laminated body, and supplying the reinforcing fibers to the reinforcing fibers. An impregnation step in which the synthetic resin is impregnated; and the reinforcing fiber impregnated with the synthetic resin is made into a fiber reinforced plastic layer by solidifying or curing the synthetic resin, and the fiber reinforced plastic layer is used as a surface of the foam molded body. A method of manufacturing a fiber reinforced composite including an integration step of laminating and integrating, wherein in the impregnation step, the amount of movement of the reinforcing fibers in the surface direction of the foamed molded product is 0.05 to 10%. It is characterized by being.

  The form of the foam-molded body 1 used in the method for producing a fiber-reinforced composite is not limited to the sheet shape as shown in FIG. 1 and may be any desired shape.

  The synthetic resin constituting the foamed molded body 1 is not particularly limited, and examples thereof include polycarbonate resins, acrylic resins, thermoplastic polyester resins, polyphenylene ether resins, polymethacrylimide resins, polyolefin resins, and polystyrene resins. Thermoplastic resins such as thermoplastic polyester resins, polystyrene resins, acrylic resins and the like because of their excellent adhesion to thermosetting resins or thermoplastic resins impregnated in fiber reinforced plastic layers. Polyphenylene ether resins are preferable, and thermoplastic polyester resins and acrylic resins are more preferable. In addition, a synthetic resin may be used independently or 2 or more types may be used together.

  The thermoplastic polyester resin is a high molecular weight linear polyester obtained as a result of a condensation reaction between a dicarboxylic acid and a dihydric alcohol. Examples of the thermoplastic polyester resin include an aromatic polyester resin and an aliphatic polyester resin.

  The aromatic polyester resin is a polyester containing an aromatic dicarboxylic acid unit and a diol unit, for example, polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polycyclohexanedimethylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, etc. And polyethylene terephthalate is preferred. Polyethylene terephthalate may be modified by adding 1,4-cyclohexanedimethanol, 1,3-propanediol, 1,4-butanediol, etc. to a part of the diol unit. In addition, an aromatic polyester resin may be used independently or 2 or more types may be used together.

  In addition to the aromatic dicarboxylic acid unit and the diol unit, the aromatic polyester resin includes, for example, a tricarboxylic acid such as trimellitic acid such as trimellitic acid, a tetracarboxylic acid such as pyromellitic acid, or a polyvalent carboxylic acid having a valence of 3 or more. Or a triol or higher polyhydric alcohol such as a triol such as glycerin or a tetraol such as pentaerythritol may be contained as a structural unit.

  As the aromatic polyester resin, a recycled material recovered and recycled from a used PET bottle or the like can be used.

  Polyethylene terephthalate may be crosslinked by a crosslinking agent. Known crosslinking agents are used, and examples thereof include acid dianhydrides such as pyromellitic anhydride, polyfunctional epoxy compounds, oxazoline compounds, and oxazine compounds. In addition, a crosslinking agent may be used independently or 2 or more types may be used together.

  When polyethylene terephthalate is crosslinked with a crosslinking agent, the crosslinking agent may be supplied to the extruder together with the polyethylene terephthalate. If the amount of the cross-linking agent supplied to the extruder is too small, the melt viscosity at the time of melting of the polyethylene terephthalate may become too small, and bubbles may be broken, and if it is too much, the melt viscosity at the time of melting of the polyethylene terephthalate. Becomes too large, and extrusion foaming may be difficult when the foamed molded article is produced by extrusion foaming. Therefore, 0.01 to 5 parts by weight with respect to 100 parts by weight of polyethylene terephthalate is preferable. -1 part by weight is more preferred.

  Examples of the aliphatic polyester resin include a polylactic acid resin. As the polylactic acid-based resin, a resin in which lactic acid is polymerized by an ester bond can be used. From the viewpoint of commercial availability and imparting foamability to the polylactic acid-based resin expanded particles, D-lactic acid (D-form) 1 or 2 selected from the group consisting of a copolymer of L-lactic acid (L-form), a homopolymer of either D-lactic acid or L-lactic acid, D-lactide, L-lactide and DL-lactide The above lactide ring-opening polymer is preferred. In addition, polylactic acid-type resin may be used independently, or 2 or more types may be used together.

  Examples of the polyphenylene ether resin include a mixture of a polyphenylene ether and a polystyrene resin, a modified polyphenylene ether obtained by graft copolymerization of a styrene monomer with a polyphenylene ether, a mixture of this modified polyphenylene ether and a polystyrene resin, and a phenolic resin. Examples thereof include a block copolymer obtained by oxidative polymerization of a monomer and a styrene monomer in the presence of a catalyst such as an amine complex of copper (II), a mixture of this block copolymer and a polystyrene resin, and the like. In addition, polyphenylene ether resin may be used independently or 2 or more types may be used together.

  Examples of the polyphenylene ether resin include poly (2,6-dimethylphenylene-1,4-ether), poly (2,6-diethylphenylene-1,4-ether), and poly (2,6-dichlorophenylene- 1,4-ether), poly (2,6-dibromophenylene-1,4-ether), poly (2-methyl-6-ethylphenylene-1,4-ether), poly (2-chloro-6-methyl) Phenylene-1,4-ether), poly (2-methyl-6-isopropylphenylene-1,4-ether), poly (2,6-di-n-propylphenylene-1,4-ether), poly (2 -Bromo-6-methylphenylene-1,4-ether), poly (2-chloro-6-bromophenylene-1,4-ether), poly (2-chloro-6-ethylphenyle) 1,4 ether). The degree of polymerization of the polyphenylene ether resin is usually 10 to 5000.

  The acrylic resin is produced by polymerizing a (meth) acrylic monomer. In addition, (meth) acryl means either one or both of acryl and methacryl.

  The (meth) acrylic monomer is not particularly limited, and (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, lauryl (meth) acrylate, (meth ) 2-ethylhexyl acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, (meth) acrylamide and the like.

  The acrylic resin may contain a monomer unit copolymerizable with the above (meth) acrylic monomer. Examples of such monomers include maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, crotonic acid, maleic amide, maleic imide and the like.

  The polystyrene resin is not particularly limited, and for example, a homopolymer or copolymer containing a styrene monomer such as styrene, methylstyrene, ethylstyrene, i-propylstyrene, dimethylstyrene, chlorostyrene, bromostyrene as a monomer unit. Copolymers, copolymers containing styrene monomers, and one or more vinyl monomers copolymerizable with the styrene monomers as monomer units, and the like. A copolymer containing one or more possible vinyl monomers as monomer units is preferred, and a copolymer containing methacrylic acid and / or methyl methacrylate and a styrene monomer as monomer units is more preferred. In addition, a polystyrene resin may be used independently or 2 or more types may be used together.

  Examples of vinyl monomers copolymerizable with styrenic monomers include acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid, acrylic acid esters (methyl acrylate, ethyl acrylate, butyl acrylate, etc.), and methacrylic acid esters (methacrylic acid). Acrylic monomers such as methyl acid, ethyl methacrylate, butyl methacrylate, etc.), maleic anhydride, acrylamide and the like, acrylic monomers are preferred, methacrylic acid and methyl methacrylate are more preferred, methacrylic acid, Methyl methacrylate is particularly preferred.

  The method for producing the foam molded body 1 is not particularly limited. For example, (1) foam particles having re-foamability are filled in a mold, and the foam particles are heated by a heat medium such as hot water or steam. A method for producing a foamed molded product having a desired shape by re-foaming and fusing the foamed particles together by the foaming pressure of the foamed particles (in-mold foam molding method), (2) supplying thermoplastic resin to the extruder A foamed molded article having a desired shape, such as a method of producing a foamed molded article by melt-kneading in the presence of a physical foaming agent and extrusion foaming from a die attached to an extruder (extruded foam molding method). Therefore, the in-mold foam molding method is preferable.

  Examples of physical foaming agents include propane, normal butane, isobutane, normal pentane, isopentane, hexane and other saturated aliphatic hydrocarbons, dimethyl ether and other ethers, methyl chloride, 1,1,1,2-tetrafluoro Examples include chlorofluorocarbons such as ethane, 1,1-difluoroethane, monochlorodifluoromethane, carbon dioxide, nitrogen, etc., preferably dimethyl ether, propane, normal butane, isobutane, carbon dioxide, more preferably propane, normal butane, isobutane, and normal butane. Isobutane is particularly preferred. In addition, a physical foaming agent may be used independently or 2 or more types may be used together.

  You may age the obtained foaming molding and reduce the quantity of the foaming agent contained in the foaming molding (aging process). In the aging step, if the ambient temperature when aging the foam molded product is too low, the amount of the foaming agent contained in the foam molded product may not be reduced. Deformation may occur and the appearance of the resulting fiber-reinforced composite may be deteriorated, so 40 to 80 ° C is preferable, and 50 to 70 ° C is more preferable.

  In the aging step, if the time for aging the foamed molded product is too short, the amount of the foaming agent contained in the foamed molded product may not be reduced. Depending on the case, the foamed molded product may be deformed and the appearance of the resulting fiber-reinforced composite may be deteriorated. Therefore, 48 to 216 hours are preferable, and 72 to 168 hours are more preferable.

  The amount of the remaining foaming agent in the foamed molded product is appropriately changed in size in the impregnation step to be described later to improve the orientation of the reinforcing fiber or promote free movement of the reinforcing fiber into the reinforcing fiber. 0.05 to 1.0% by weight is preferable because the impregnation of the synthetic resin can be made uniform and sufficient and the mechanical strength of the resulting fiber-reinforced plastic layer can be improved.

The amount of the remaining foaming agent in the foamed molded product is measured as follows. The weight W ₁ of the entire foamed molded product is measured. The amount of residual foaming agent in the foamed molded product can be measured using a gas chromatograph. For example, the amount of residual foaming agent in the foamed molded product can be measured using the following apparatus under the following conditions.

Place 10-30 mg of the foamed molded sample in a 20 mL vial, precisely weigh it, seal the vial and set it on a gas chromatograph with an autosampler, heat the vial at 210 ° C. for 20 minutes, The gas in the upper space of the bottle is quantitatively analyzed by the MHE (Multiple Headspace Extraction) method, and the gas content W ₂ in the foamed molded product is measured.

The MHE method referred to here is a quantitative method that utilizes the attenuation of the peak area obtained by repeating the release of gas phase gas in gas-solid equilibrium.
[GC measurement conditions]
Measuring device: Gas chromatograph Clarus500 (Perkin-Elmer)
Column: DB-1 (1.0 μm × 0.25 mmφ × 60 m: manufactured by J & W)
Detector: FID
GC oven temperature rising condition: initial temperature 50 ° C. (6 minutes)
Temperature increase rate: 40 ° C / min (up to 250 ° C)
Final temperature: 250 ° C (1.5 minutes)
Carrier gas (He), inlet temperature: 230 ° C, detection temperature: 310 ° C
Range: 20
Vent gas 30 mL / min (He), additional gas 5 mL / min (He)
Gas pressure: Initial pressure 18 psi (10 minutes), pressurization speed: 0.5 psi / min (up to 24 psi)
[HS measurement conditions]
Measuring device: HS autosampler TurboMatrix HS40 (Perkin-Elmer)
Heating temperature: 210 ° C, heating time: 20 minutes, pressurized gas pressure: 25 psi, pressurizing time: 1 minute Needle temperature: 210 ° C, transfer line temperature: 210 ° C, sample introduction time: 0.08 minutes [Calculation conditions]
Standard gas for calibration curve: Gas mixture (manufactured by GL Sciences Inc.)
Mixed gas content: i-butane about 1% by weight, n-butane about 1% by weight, balance nitrogen Calculation method: The amount of gas contained in the sample was calculated by the MHE method. The results were all converted to i-butane.

The amount of the remaining foaming agent in the foamed molded product can be calculated based on the following formula.
Residual foaming agent amount (% by weight) in the foamed molded product = 100 × W ₂ / W ₁

  If the crystallinity of the surface layer of the foam molded product is too low, the foam molded product may be deformed by the heat of the synthetic resin in the impregnation step, and the appearance of the resulting fiber reinforced composite may be reduced. If the amount is too high, the fiber-reinforced plastic layer and the foamed molded body may be insufficiently integrated and the mechanical strength may be lowered, so 5 to 40% is preferable, and 10 to 30% is more preferable.

  The surface layer of the foam-molded body is between the surface of the foam-molded body and a portion that is inside by a dimension corresponding to 5% of the thickness of the foam-molded body in the direction perpendicular to the surface. This refers to the part of the foamed molded product that exists.

  The crystallinity of the surface layer of the foam molded article is measured by the method described in JIS K7122: 1987 “Method for measuring the transition heat of plastic”.

  Specifically, using a differential scanning calorimeter (trade name “DSC6220 type” manufactured by SII Nano Technology Co., Ltd.), it was cut out from the surface layer of the foamed molded product so that there was no gap at the bottom of the aluminum measurement container. Preferably, about 6 mg of a rectangular parallelepiped sample is filled, and the sample is held at 30 ° C. for 2 minutes under a nitrogen gas flow rate of 30 mL / min.

Thereafter, a DSC curve is obtained when the sample is heated from 30 ° C. to 290 ° C. at a rate of 10 ° C./min. The reference material at that time was alumina. The degree of crystallinity of the surface layer of the foamed molded product is the difference between the heat of fusion (mJ / mg) determined from the area of the melting peak and the heat of crystallization (mJ / mg) determined from the area of the crystallization peak. This is the ratio that is gradually determined by the theoretical heat of fusion ΔH ₀ of the crystal. For example, ΔH ₀ of polyethylene terephthalate is 140.1 mJ / mg. The crystallinity of the surface layer of the foam molded product is calculated based on the following formula.
Crystallinity of surface layer of foamed molded product (%)
= 100 × (| heat of fusion (mJ / mg) | − | heat of crystallization (mJ / mg) |) / ΔH ₀ (mJ / mg)

  Separately, four foam moldings are further prepared, and the degree of crystallinity of the surface layer of each foam molding is measured in the same manner as described above, and the degree of crystallinity of each surface layer of the five foam moldings is measured. The arithmetic average value is defined as the crystallinity of the surface layer of the foam molded article.

  As a method for producing re-expandable foam particles used in the in-mold foam molding method, (1) a synthetic resin is supplied into an extruder, melt-kneaded in the presence of a physical foaming agent, and attached to the extruder. A method in which a synthetic resin extrudate is cut while being extruded and foamed from a nozzle mold and then cooled to produce expanded particles. (2) The synthetic resin is supplied into an extruder and melt-kneaded in the presence of a physical foaming agent. A method of producing a synthetic resin extrudate in the form of a strand by extruding and foaming from a nozzle mold attached to an extruder, and cutting the synthetic resin extrudate at predetermined intervals, (3) Synthesis A resin is supplied into an extruder, melted and kneaded in the presence of a physical foaming agent, extruded and foamed from an annular die or a T-die attached to the extruder to produce a foam, and then synthesized by cutting the foam Those who produce resin foam particles And the like.

  In the impregnation step described later, it is preferable that the foam molded article undergo a dimensional change appropriately. Specifically, the dimensional change rate of the foam molded article under a reduced pressure of 100 ° C. and 0.1 MPa is −2 to 10%. Preferably, -1.5 to 5% is more preferable. Uniform and sufficient impregnation of the synthetic resin into the reinforcing fiber by improving the orientation of the reinforcing fiber or promoting the free movement of the reinforcing fiber by appropriately changing the size of the foam molded article during the impregnation process. And the mechanical strength of the resulting fiber-reinforced plastic layer can be improved. The dimensional change rate of the foam molded body can be controlled, for example, by adjusting the atmospheric temperature or the aging time in the aging step described above and adjusting the amount of the foaming agent contained in the foam molded body.

  In addition, the dimensional change rate in 100 degreeC and the pressure_reduction | reduced_pressure of 0.1 Mpa in a foaming molding means the value measured in the following way. A rectangular parallelepiped test piece having a length of 40 mm, a width of 40 mm, and a thickness of 30 mm is cut out from the foamed molded article, and the test piece is left to stand at 23 ° C. and a relative humidity of 60% for 24 hours. The thickness of this test piece is measured at three arbitrary locations, and the arithmetic average value of the thicknesses at these three locations is taken as the “dimension before heating” of the test piece.

Next, after supplying the test piece into an oven maintained at 100 ° C., the pressure inside the oven was reduced to 0.1 MPa, and the test piece was left in the oven for 15 minutes. Thereafter, the test piece was taken out of the oven and allowed to stand for 1 hour at 23 ° C. and 60% relative humidity under normal pressure. The thickness of the test piece is measured at the same three places measured before heating, and the arithmetic average value of the thicknesses at these three places is taken as the “dimension after heating” of the test piece. The dimensional change rate is calculated based on the following formula. When the dimensional change rate becomes a negative value, the test piece is contracted. When the dimensional change rate becomes a positive value, the test piece is expanded. In addition, as an oven, the vacuum oven marketed with the brand name "LHV-112" from the TABAI ESPEC CORP company can be used.
Dimensional change rate (%) = 100 × (size after heating−size before heating) / size before heating

Apparent density of the expanded molded article 1 is preferably ^{0.05~1.2g / cm 3, 0.08~0.9g / cm} 3 is more preferable. If the apparent density of the foam molded article 1 is too low, the mechanical strength of the fiber-reinforced composite may be lowered. If the apparent density of the foamed molded product 1 is too high, the lightweight property of the fiber-reinforced composite may be lowered. The apparent density of the foamed molded product refers to a value measured according to JIS K7222 “Foamed plastics and rubber—Measurement of apparent density”. The apparent density of the foam molded body 1 of the fiber reinforced composite B is measured based on the foam molded body after the fiber reinforced plastic layer 4 is peeled from the fiber reinforced composite B.

  If the degree of surface irregularity of the foamed molded article 1 is too large, the appearance of the fiber-reinforced composite may be deteriorated, so 0.4 mm or less is preferable, and 0.3 mm or less is more preferable. In addition, the surface unevenness degree of the foaming molding 1 cut | disconnects a foaming molding, and image | photographs the cut surface at 200 time using a scanning electron microscope. The maximum value of the depth of the concave / convex concave portion (difference between the lowest portion of the concave portion and the apex of the convex portion adjacent to the concave portion) appearing in the enlarged photograph is defined as the degree of surface irregularity of the foam molded article. Moreover, when the groove part mentioned later is formed in the surface of the foaming molding 1, in measuring the surface unevenness degree of a foaming molding, a groove part is excluded.

  The laminate A is manufactured by laminating the reinforcing fibers 2 on at least one surface of the foamed molded body 1 (lamination step). When the foam molded body 1 is a foam sheet, it is not necessary to laminate reinforcing fibers on both sides of the foam molded body 1 as shown in FIG. What is necessary is just to laminate | stack. What is necessary is just to determine suitably lamination | stacking of a reinforced fiber according to the use of a fiber reinforced composite. Among these, in consideration of the surface hardness and mechanical strength of the fiber reinforced composite, it is preferable to laminate reinforcing fibers on both surfaces in the thickness direction of the foam molded body 1.

Reinforcing fibers include glass fibers, carbon fibers, silicon carbide fibers, alumina fibers, Tyranno fibers (registered trademark) , basalt fibers, ceramic fibers, and other inorganic fibers; stainless steel fibers, steel fibers, and other metal fibers; aramid fibers, polyethylene fibers Organic fibers such as polyparaphenylene benzoxador (PBO) fiber; boron fiber and the like. Reinforcing fibers may be used alone or in combination of two or more. Among these, carbon fiber, glass fiber, and aramid fiber are preferable, and carbon fiber is more preferable. These reinforcing fibers have excellent mechanical strength despite being lightweight.

  The reinforcing fiber is preferably used as a reinforcing fiber substrate processed into a desired shape. Examples of the reinforcing fiber base material include woven fabrics, knitted fabrics, nonwoven fabrics, and face materials obtained by binding (sewing) fiber bundles (strands) obtained by aligning reinforcing fibers in one direction with yarns. . Examples of the weaving method include plain weave, twill weave and satin weave. Examples of the yarn include synthetic resin yarn such as polyamide resin yarn and polyester resin yarn, and stitch yarn such as glass fiber yarn. As a reinforced fiber base material, what is marketed by Mitsubishi Rayon under the brand name "Pyrofil" can be used, for example.

  The reinforcing fiber substrate may be used without laminating only one reinforcing fiber substrate, or a plurality of reinforcing fiber substrates may be laminated and used as a laminated reinforcing fiber substrate. As a laminated reinforcing fiber base material in which a plurality of reinforcing fiber base materials are laminated, (1) a plurality of reinforcing fiber base materials of only one kind are prepared, and a laminated reinforcing fiber base material in which these reinforcing fiber base materials are laminated, 2) A plurality of types of reinforcing fiber base materials are prepared, a laminated reinforcing fiber base material obtained by laminating these reinforcing fiber base materials, and (3) a fiber bundle (strand) in which the reinforcing fibers are aligned in one direction is bound with a thread ( A plurality of reinforcing fiber base materials prepared by stitching) are prepared, and these reinforcing fiber base materials are superposed so that the fiber directions of the fiber bundles are different from each other. A laminated reinforcing fiber base material integrated (stitched) with is used. Examples of the yarn include synthetic resin yarns such as polyamide resin yarns and polyester resin yarns, and stitch yarns such as glass fiber yarns.

  The thickness of the reinforcing fiber 2 is preferably 0.02 to 2 mm, and more preferably 0.05 to 1 mm. By using the reinforcing fiber having a thickness within the above range, the obtained fiber-reinforced plastic layer is excellent in mechanical strength despite being lightweight.

Basis weight of the reinforcing fibers 2 is preferably ^{50~4000g / m 2, 100~1000g / m} 2 is more preferable. By using the reinforcing fiber having a basis weight within the above range, the obtained fiber-reinforced plastic layer is excellent in mechanical strength despite being lightweight.

  Before the impregnation step described later, it is preferable that the foam molded body 1 and the reinforcing fibers 2 laminated on the surface of the foam molded body 1 are temporarily fixed. Before the reinforcing fiber is impregnated with the synthetic resin, the foam molded body 1 and the reinforcing fiber 2 are temporarily fixed, and the foam molded body 1 and the reinforcing fiber 2 are temporarily fixed with the synthetic resin impregnated in the reinforcing fiber. Is preferably released. In the initial stage of the impregnation step in which the reinforcing fiber is impregnated with the synthetic resin, since the resistance when the reinforcing fiber is impregnated with the synthetic resin is relatively large, the entire reinforcing fiber is easy to move on the surface of the foam molded body. Therefore, in the process of impregnating the reinforcing fiber with the synthetic resin, the reinforcing fiber is temporarily placed on the surface of the foam molded body in order to dispose the reinforcing fiber at a desired position of the foam molded body without generating wrinkles or the like in the reinforcing fiber. It is preferable to fix it. As the process of impregnating the reinforced fiber with the synthetic resin progresses, the reinforced fiber and the synthetic resin become familiar, and the resistance when the reinforced fiber is impregnated with the synthetic resin gradually decreases. It is not necessary to fix it to the surface of the body, and in the process excluding the initial stage of the impregnation of the synthetic resin into the reinforcing fiber, the temporary fixing between the reinforcing fiber and the foamed molded body is released and strengthened as described later. It is rather preferable to ensure free movement of the fiber.

  In addition, when using a lamination | stacking reinforcing fiber base material as a reinforcing fiber, it is preferable that the reinforcing fiber base materials are also temporarily fixed for the same reason as the above.

  The temporary fixing between the reinforcing fiber and the foamed molded body and the temporary fixing between the reinforcing fiber bases may be performed using a synthetic resin similar to a synthetic resin described later impregnated in the reinforcing fiber or a general-purpose glue as a temporary fixing agent. However, when the temporary fixing agent comes into contact with the synthetic resin in a molten state impregnated in the reinforcing fibers, it is necessary to melt and fix the fixing force.

If the reinforcing fiber is temporarily fixed to the surface of the foamed molded product, if the temporary fixing force is too small, the reinforcing fiber moves from a desired position on the surface of the foamed molded product in the step of impregnating the reinforcing fiber with the synthetic resin. Or, there is a possibility that wrinkles may occur in the reinforcing fiber, and if it is too large, the state in which the reinforcing fiber is fixed to the surface of the foamed molded article is unexpectedly maintained in the impregnation step, and the reinforcing fiber is free to move. As a result, impregnation of the synthetic resin into the reinforced fiber is not performed smoothly, and the resulting fiber reinforced plastic layer may be insufficiently integrated with the foamed molded product. fear that bubbles are generated, or because there is a possibility that wrinkles are generated in the fiber reinforced plastic layer lowers the appearance of the fiber-reinforced composite, preferably ^{1~30N / cm 2, 1~20N / cm} 2 is More preferable 1 to 10 N / cm ² is particularly preferable, and 1 to 5 N / cm ² is most preferable.

  In addition, the temporary fixing force of the reinforcing fiber to the surface of the foamed molded product is a shear tension measured at a test speed of 10 mm / min using a test piece cut out from the laminate in accordance with JIS K6850 (1999). I say power. The temporary fixing force of the reinforcing fiber to the surface of the foamed molded product can be measured using, for example, a small tabletop testing machine (trade name “FGS-1000TV / 1000N + FGP-100” manufactured by Nidec Symposium).

Moreover, when using a laminated reinforcing fiber base material in which a plurality of reinforcing fiber base materials are laminated as reinforcing fibers, if the temporary fixing force between the reinforcing fiber bases is too small, the reinforcing fibers are impregnated with a synthetic resin. In the process, the reinforcing fiber base may move from a desired position on the surface of the foam molded body, or wrinkles may occur in the reinforcing fiber base. If it is too large, the reinforcing fiber base is reinforced in the impregnation step. The free movement of the fibers is obstructed, and as a result, the synthetic fiber is not smoothly impregnated into the reinforcing fiber substrate, and the resulting fiber-reinforced plastic layer and the foamed molded product may not be sufficiently integrated. In addition, there is a possibility that bubbles may be generated in the fiber reinforced plastic layer, or wrinkles may be generated in the fiber reinforced plastic layer and the appearance of the fiber reinforced composite may be reduced, so 1 to 30 N / cm ² is preferable. 1~20N / cm ² Gayori preferable.

  In addition, the temporary fixing force between the reinforcing fiber bases is based on JIS K6850 (1999), except that the specimen cut out from the laminated reinforcing fiber base is used as a reinforcing fiber to the surface of the foam molded body. The value measured in the same manner as the temporary fixing force.

  Next, as shown in FIG. 1, after the laminate A is supplied into the male and female molds 31 and 32, the male and female molds 31 and 32 are clamped. Thereafter, a synthetic resin in a molten state is supplied into the cavity 33 of the male and female molds 31 and 32 through a resin supply path (not shown) so that the reinforcing fiber 2 is entirely impregnated with the synthetic resin and the reinforcing fiber 2 The synthetic resin is spread over the entire surface of the foam molded body 1 (impregnation step). When supplying synthetic resin into the cavity 33 of the male and female molds 31, 32, the synthetic resin may be press-fitted into the cavity 33 of the male and female molds 31, 32, or the synthetic resin may be injected into the cavity of the male and female molds 31, 32. 33 may be supplied under atmospheric pressure, but the reinforcing fiber can be more uniformly impregnated with a synthetic resin, and the resulting fiber-reinforced plastic layer can be more firmly laminated and integrated into the foam molded body. It is preferable to press-fit the synthetic resin into the cavity 33 of the male and female molds 31 and 32.

  By forming a groove for resin distribution on the surface of the foam molded body 1, the synthetic resin impregnated in the reinforcing fiber and reaching the interface between the reinforcing fiber 2 and the foam molded body 1 is passed through the groove for resin distribution. The interface between the reinforcing fiber 2 and the foam molded body 1 can be spread over the entire time in a short time, and a fiber reinforced composite can be produced in a short time. The body can be integrated more firmly.

  For example, a plurality of groove portions for resin distribution may be formed in parallel on the surface of the foam molded body with a predetermined interval. If the width of the groove for resin circulation is too narrow, the synthetic resin may not flow smoothly. If it is too wide, the integration of the reinforcing fiber and the foamed molded article may be hindered. 5-5 mm is preferable and 1-3 mm is more preferable. The width of the groove for resin circulation refers to the width of the opening end of the groove.

  If the depth of the resin distribution groove is too deep, the reinforcing fibers fall into the resin distribution groove, and the reinforcing fibers are not uniformly impregnated with synthetic resin. The strength may be reduced, or the appearance of the fiber reinforced plastic layer obtained may be reduced by dropping the reinforcing fiber into the groove for resin circulation, so 0.5 to 10 mm is preferable. 5 mm is more preferable.

  If the gap (pitch) between the groove portions for resin circulation is too small, a lot of synthetic resin may be impregnated in the groove portions and lightness may be lost.If it is too large, the synthetic resin may not flow smoothly. Therefore, 2 to 50 mm is preferable, and 3 to 30 mm is more preferable.

  In the impregnation step, the reinforcing fiber 2 is impregnated with the synthetic resin. During the impregnation, the reinforcing fiber 2 is adjusted to move within a predetermined range. By moving the reinforcing fiber within a predetermined range during the impregnation of the synthetic resin into the reinforcing fiber, the impregnation of the synthetic resin into the reinforcing fiber is performed almost uniformly and smoothly and is included in the reinforcing fiber. Air is smoothly removed along with the impregnation of the synthetic resin into the reinforcing fiber, and the reinforcing fiber is firmly bonded and integrated with the synthetic resin. The resulting fiber-reinforced plastic layer has excellent mechanical strength.

  Furthermore, since the reinforcing fiber is smoothly impregnated with the synthetic resin, no extra external force is unexpectedly applied to the reinforcing fiber, and the reinforcing fiber is not deformed or wrinkled on the reinforcing fiber. The resulting fiber reinforced plastic layer has an excellent appearance.

  Further, as described above, the reinforcing fiber moves within a predetermined range, so that the reinforcing resin is substantially uniformly impregnated into the reinforcing fiber as described above, and a part of the synthetic resin impregnated into the reinforcing fiber is part of the reinforcing fiber. The whole surface is supplied to the interface between the reinforcing fiber and the foam molded body, and the supplied synthetic resin pushes and removes the air present at the interface between the reinforcing fiber and the foam molded body. Therefore, the obtained fiber-reinforced plastic layer and the foamed molded body are firmly integrated by the synthetic resin supplied to the interface between the reinforcing fiber and the foamed molded body.

  In this way, during the impregnation step, the reinforcing fibers move with an appropriate degree of freedom, so that the synthetic fibers are impregnated substantially uniformly and smoothly in the reinforcing fibers, and the reinforcing fibers and the reinforcing fibers and the foamed molding. Air present at the interface with the body is also smoothly removed, and the resulting fiber reinforced plastic layer has excellent appearance and mechanical strength, and the fiber reinforced plastic layer is firmly integrated with the foamed molded product, and the resulting fiber reinforced The composite has excellent appearance and mechanical strength.

  Specifically, the moving amount of the reinforcing fiber during the impregnation step is limited to 0.05 to 10% in the surface direction of the foamed molded article on which the reinforcing fiber is laminated, and preferably 0.05 to 5%. The moving amount of the reinforcing fiber during the impregnation step is determined by the magnitude of the pressing force applied to the laminate in the lamination direction of the reinforcing fiber relative to the foam molded product, the basis weight of the reinforcing fiber, and the temporary fixing force of the reinforcing fiber to the surface of the foam molded product Alternatively, it can be controlled by adjusting a temporary fixing force between the reinforcing fiber bases.

The moving amount of the reinforcing fiber is a value measured in the following manner. A planar square measurement point (initial area S ₀ : 1 cm ² ) having a side of 1 cm is drawn on the surface of the reinforcing fiber of the laminate produced in the lamination step. As the ink for drawing the measurement point, an ink that causes color transfer when it comes into contact with another member is used. The measurement point should not affect the impregnation of the reinforcing fiber with the synthetic resin.

Next, after performing the impregnation step as described later, the ink used to draw the measurement point on the surface of the reinforcing fiber is transferred to the mold surface or the flexible film. The total area S ₁ (cm ² ) subjected to this color transfer is calculated and calculated based on the following formula.
Transfer amount (%) of reinforcing fiber = 100 × (S ₁ −S ₀ ) / S ₀

  The temperature of the molten synthetic resin supplied into the cavity 33 of the male and female molds 31 and 32 is adjusted to be lower than the glass transition temperature Tg of the synthetic resin constituting the foamed molded body 1. As described above, by adjusting the temperature of the synthetic resin in the molten state and the glass transition temperature Tg of the synthetic resin constituting the foam molded article, the synthetic resin supplied into the cavity 33 of the male and female molds 31 and 32 The synthetic resin can be smoothly impregnated into the reinforcing fiber while preventing the foamed molded body 1 from being deformed by foaming, and the synthetic resin can be smoothly applied to the interface between the reinforcing fiber and the foamed molded product. The reinforcing fiber can be integrated with the surface of the foamed molded product having a desired shape, and the resulting fiber-reinforced composite has excellent mechanical strength and appearance.

  In the present invention, the glass transition temperature of the thermoplastic resin is measured by the method described in JIS K7121: 1987 "Method for measuring plastic transition temperature". However, the sampling method and temperature conditions are as follows. Using a differential scanning calorimeter device, about 6 mg of the sample is filled so that there is no gap at the bottom of the aluminum measurement container, and the sample is cooled from 30 ° C. to −40 ° C. for 10 minutes under a nitrogen gas flow rate of 20 mL / min. The sample was heated from -40 ° C. to 290 ° C. (1st Heating), held at 290 ° C. for 10 minutes, and then cooled from 290 ° C. to −40 ° C. (Cooling) for 10 minutes. The DSC curve was obtained when the temperature was raised from −40 ° C. to 290 ° C. (2nd Heating). In addition, all the temperature increase rates and temperature decrease rates are performed at 10 ° C./min, and alumina is used as a reference material. In the present invention, the glass transition temperature refers to the midpoint glass transition temperature obtained from the DSC curve obtained in the 2nd Heating process. The midpoint glass transition temperature is obtained from JIS K7121: 1987 (9.3 “How to Obtain Glass Transition Temperature”). In addition, as a differential scanning calorimeter apparatus, the differential scanning calorimeter apparatus marketed by the SII nanotechnology company by the brand name "DSC6220 type | mold" can be used, for example.

  In the present invention, the glass transition temperature of the thermosetting resin refers to a temperature measured in the following manner. When measuring the glass transition temperature of a thermosetting resin, it is necessary to harden the thermosetting resin in advance. The curing temperature of the thermosetting resin is set to an exothermic peak temperature ± 10 ° C. measured in JIS K7121: 1987. The curing time of the thermosetting resin is 60 minutes as a guide. When the exothermic peak of the thermosetting resin after curing is measured according to JIS K7121: 1987, the curing is complete if no exothermic peak is observed. The glass transition temperature of the thermosetting resin is measured in the manner described later using the cured thermosetting resin. In addition, the detailed measuring method of the exothermic peak temperature used as the standard of the curing temperature of the thermosetting resin mentioned above is as follows. The exothermic peak temperature of the thermosetting resin is measured by the method described in JIS K7121: 1987 “Method for measuring plastic transition temperature”. However, the sampling method and temperature conditions are as follows. Using a differential scanning calorimeter device, about 6 mg of the sample is filled so that there is no gap at the bottom of the aluminum measurement container, alumina is used as a reference material under a nitrogen gas flow rate of 20 mL / min, and the sample is heated from 30 ° C. to 220 ° C. The temperature is raised to 5 ° C. at a rate of 5 ° C./min. In the present invention, the exothermic peak temperature of the thermosetting resin is a value obtained by reading the temperature at the peak top at the first temperature rise. In addition, as a differential scanning calorimeter apparatus, the differential scanning calorimeter apparatus marketed by the SII nanotechnology company by the brand name "DSC6220 type | mold" can be used, for example.

  The glass transition temperature of the thermosetting resin is a temperature measured in accordance with 9.3 “How to obtain glass transition temperature” in JIS K7121 (1987) “Method for measuring plastic transition temperature”. Specifically, 6 mg of a thermosetting resin after curing for measuring the glass transition temperature is taken as a sample. Using a differential scanning calorimeter device, the sample was heated from 30 ° C. to 200 ° C. at a rate of temperature increase of 20 ° C./min in a nitrogen gas flow at a flow rate of 20 mL / min. Hold for a minute. Thereafter, the sample is quickly taken out from the apparatus and cooled to 25 ± 10 ° C., and then the sample is again heated to 200 ° C. at a heating rate of 20 ° C./min under a nitrogen gas flow rate of 20 mL / min in the apparatus. The glass transition temperature (intermediate point) is calculated from the DSC curve obtained when the temperature is raised. In the measurement, alumina is used as a reference material. In addition, as a differential scanning calorimeter apparatus, the differential scanning calorimeter apparatus marketed by the SII nanotechnology company by the brand name "DSC6220 type | mold" can be used, for example.

In the impregnation step, the surface of the foam molded body 1 is preferably heated to 10 to 90 ° C., more preferably 15 to 80 ° C., and then the reinforcing fibers are impregnated with the synthetic resin. By maintaining the surface of the foam molded body 1 in the above temperature range, the synthetic resin supplied to the reinforcing fibers is prevented from solidifying or resulting in poor flow due to a decrease in melt viscosity. The synthetic resin can be impregnated substantially uniformly, and the synthetic resin can be substantially uniformly supplied also to the interface between the reinforcing fiber and the foamed molded body. Furthermore, when the foam molded body 1 undergoes a dimensional change in the impregnation process, the dimensional change of the foam molded body starts from the initial stage of the impregnation process, and the orientation of the reinforcing fibers can be improved. In particular, when the foam molded body 1 expands in the impregnation step, the foam molded body is prevented from being crushed by the supply pressure of the synthetic resin, and the reinforcing fiber is pressed against the mold or a flexible film described later. Thus, the orientation of the reinforcing fiber can be further improved. Therefore, it is possible to form a fiber reinforced plastic layer having excellent appearance and mechanical strength, and to improve the mechanical strength and appearance of the fiber reinforced composite by firmly laminating and integrating the fiber reinforced plastic layer on the foam molded body. Can be made.

  In the impregnation step, the temperature of the synthetic resin impregnated into the reinforcing fiber is preferably 40 to 90 ° C, more preferably 50 to 80 ° C. By maintaining the temperature of the synthetic resin in the above temperature range, it prevents the synthetic resin supplied to the reinforcing fiber from solidifying or causing a flow failure due to a decrease in melt viscosity, and the reinforcing fiber has a synthetic resin. Can be impregnated substantially uniformly, and the synthetic resin can also be supplied substantially uniformly to the interface between the reinforcing fiber and the foamed molded product. Furthermore, when the foam molded body 1 undergoes a dimensional change in the impregnation process, the dimensional change of the foam molded body starts from the initial stage of the impregnation process, and the orientation of the reinforcing fibers can be improved. In particular, when the foam molded body 1 expands in the impregnation step, the foam molded body is prevented from being crushed by the supply pressure of the synthetic resin, and the reinforcing fiber is pressed against the mold or a flexible film described later. Thus, the orientation of the reinforcing fiber can be further improved. Therefore, it is possible to form a fiber reinforced plastic layer having excellent appearance and mechanical strength, and to improve the mechanical strength and appearance of the fiber reinforced composite by firmly laminating and integrating the fiber reinforced plastic layer on the foam molded body. Can be made.

  In the impregnation process, if the difference between the surface temperature of the foam molded body before impregnating the reinforcing fiber with the synthetic resin and the temperature of the synthetic resin supplied to the reinforcing fiber is large, the synthetic resin supplied to the reinforcing fiber is the foam molded body. The melt viscosity of the synthetic resin fluctuates in the process of being impregnated in the reinforcing fiber by being heated or cooled by, and the fluidity of the synthetic resin fluctuates in the reinforcing fiber. And the appearance of the fiber-reinforced plastic layer to be obtained may be lowered or the mechanical strength may be lowered. Therefore, the temperature is preferably 60 ° C. or lower, more preferably 50 ° C. or lower, and particularly preferably 40 ° C. or lower.

  Part of the synthetic resin supplied into the cavity 33 of the male and female molds 31 and 32 is sequentially discharged out of the male and female molds 31 and 32 through a resin discharge path (not shown). The synthetic resin may be discharged out of the cavity 33 of the male and female molds 31 and 32 under atmospheric pressure, or may be actively sucked and discharged using a vacuum pump or the like.

  In this way, while the synthetic resin is continuously supplied to the laminate A accommodated in the cavity 33 of the male and female molds 31 and 32, excess synthetic resin is discharged out of the cavity 33 of the male and female molds 31 and 32. By this, it is possible to supply the synthetic resin to the reinforcing fiber 2 of the laminate A and the interface between the reinforcing fiber 2 and the foamed molded body 1 as a whole and substantially uniformly, and in the reinforcing fiber 2 and Air present at the interface between the reinforcing fibers 2 and the foamed molded body 1 can be efficiently removed, and the reinforcing fibers can be tightly bonded and integrated with each other by a synthetic resin. It can be laminated in a state of being in close contact with the surface. By sucking and discharging excess synthetic resin out of the cavity 33 of the male and female molds 31 and 32, the inside of the cavity 33 of the male and female molds 31 and 32 is brought into a depressurized state, and the laminate A is disposed under a reduced pressure. Thus, the reinforcing fiber can be impregnated with a synthetic resin, and the above-described effects can be more effectively exhibited.

  As the synthetic resin impregnated into the reinforcing fiber 2, either a thermoplastic resin or a thermosetting resin can be used, and a thermosetting resin is preferably used. The thermosetting resin impregnated in the reinforcing fiber 2 is not particularly limited. For example, epoxy resin, unsaturated polyester resin, phenol resin, melamine resin, polyurethane resin, silicone resin, maleimide resin, vinyl ester resin, cyanate ester Examples thereof include resins, resins obtained by prepolymerizing maleimide resins and cyanate ester resins, and the like, and epoxy resins and vinyl ester resins are preferred because they are excellent in heat resistance, impact absorption or chemical resistance. The thermosetting resin may contain additives such as a curing agent and a curing accelerator. In addition, a thermosetting resin may be used independently or 2 or more types may be used together.

  The thermoplastic resin impregnated in the reinforcing fiber 2 is not particularly limited, and examples thereof include olefin resins, polyester resins, thermoplastic epoxy resins, amide resins, thermoplastic polyurethane resins, sulfide resins, acrylic resins, and the like. Among them, polyester resins and thermoplastic epoxy resins are preferable because they are excellent in adhesiveness with the foamed molded article or adhesiveness between the reinforcing fibers constituting the fiber-reinforced plastic layer. In addition, a thermoplastic resin may be used independently or 2 or more types may be used together.

  The thermoplastic epoxy resin may be a polymer or copolymer of epoxy compounds having a linear structure, or a copolymer of an epoxy compound and a monomer that can be polymerized with the epoxy compound. And a copolymer having a linear structure. Specifically, as the thermoplastic epoxy resin, for example, bisphenol A type epoxy resin, bisphenol fluorene type epoxy resin, cresol novolac type epoxy resin, phenol novolac type epoxy resin, cyclic aliphatic type epoxy resin, long chain aliphatic type An epoxy resin, a glycidyl ester type epoxy resin, a glycidylamine type epoxy resin and the like can be mentioned, and a bisphenol A type epoxy resin and a bisphenol fluorene type epoxy resin are preferable. In addition, a thermoplastic epoxy resin may be used independently or 2 or more types may be used together.

  Examples of the thermoplastic polyurethane resin include a polymer having a linear structure obtained by polymerizing diol and diisocyanate. Examples of the diol include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, and the like. Diols may be used alone or in combination of two or more. Examples of the diisocyanate include aromatic diisocyanate, aliphatic diisocyanate, and alicyclic diisocyanate. Diisocyanate may be used independently or 2 or more types may be used together. In addition, a thermoplastic polyurethane resin may be used independently or 2 or more types may be used together.

  Next, when the synthetic resin supplied into the cavities 33 of the male and female molds 31 and 32 is a thermoplastic resin, the thermoplastic resin is solidified by cooling, and the reinforcing fibers 2 are impregnated with the synthetic resin. A fiber reinforced plastic layer 4 is formed, and this fiber reinforced plastic layer 4 can be laminated and integrated on at least one surface of the foam molded body 1 to produce a fiber reinforced composite B (see FIG. 2) (integration step). ).

  In addition, when the synthetic resin supplied into the cavity 33 of the male and female molds 31 and 32 is a thermosetting resin, the resin temperature when the thermosetting resin is supplied into the cavity 33 of the male and female molds 31 and 32 is used. The fiber reinforced plastic layer 4 is formed by impregnating the reinforced fiber 2 with a synthetic resin, and the fiber reinforced plastic layer 4 is formed into at least one of the foam-molded body 1. The fiber-reinforced composite B (see FIG. 2) can be manufactured by being laminated and integrated on the surface (integration step).

  20-70 weight% is preferable and, as for content of the synthetic resin in the fiber reinforced plastic layer 4 of the obtained fiber reinforced composite B, 30-60 weight% is more preferable. If the content of the synthetic resin is too small, the binding property between the reinforcing fibers and the adhesion between the fiber reinforced plastic layer and the foamed molded product are insufficient, and the mechanical strength of the fiber reinforced plastic layer and the fiber reinforced composite is sufficient. There is a possibility that it cannot be improved. If the content of the synthetic resin 22 is too large, the mechanical strength of the fiber reinforced plastic layer may be lowered, and the mechanical strength of the fiber reinforced composite may not be sufficiently improved.

  In the manufacturing method shown in FIG. 1, as the male and female molds 31 and 32, molds formed from a rigid body such as a metal such as steel, aluminum, or invariant steel (INVAR), fiber reinforced plastic (FRP), wood, or plaster are used. Although the case where it used was demonstrated, you may use a flexible film instead of a male metal mold | die.

  Specifically, as shown in FIG. 3, after the laminated body A is disposed in the female mold 31, the female mold 31 in which the laminated body A is disposed is surrounded by the flexible film 5. The female mold 31 is disposed in the sealed space 51 together with the laminate A in a sealed state. In addition, as a flexible film, what is necessary is just to be able to enclose the female metal mold | die 31 with which the laminated body A was arrange | positioned in the sealed state, and a synthetic resin film etc. are mentioned. Examples of the synthetic resin constituting the synthetic resin film include amide resins such as nylon, fluorine resins, and silicone resins.

  Thereafter, a synthetic resin in a molten state is supplied into the sealed space 51 so that the reinforcing fiber 2 is entirely impregnated with the synthetic resin, and the synthetic resin is spread over the interface between the reinforcing fiber 2 and the foamed molded body 1. When supplying the synthetic resin into the sealed space 51, the synthetic resin may be press-fitted into the sealed space 51, or the synthetic resin may be supplied into the sealed space 51 under atmospheric pressure. Since the synthetic resin can be more uniformly impregnated and the resulting fiber-reinforced plastic layer can be more firmly laminated and integrated with the foamed molded article, it is preferable to press-fit the synthetic resin into the sealed space 51.

  A part of the synthetic resin supplied into the sealed space 51 is sequentially discharged out of the sealed space 51. The synthetic resin may be discharged out of the sealed space 51 under atmospheric pressure, or may be positively sucked and discharged using a vacuum pump or the like. The other points are the same as those in the manufacturing method shown in FIG.

  The fiber reinforced composite obtained in this way is excellent in mechanical strength and lightness, so that it can be used for transportation equipment such as automobiles, airplanes, railway vehicles or ships, household appliances, information terminals, furniture, It can be used for a wide range of applications such as the power generation equipment field.

  For example, a fiber reinforced composite is a component of a transport device, a transport device component member (particularly a member for an automobile) including a structural member constituting the main body of the transport device, a cushioning material for a helmet, an agricultural box, a heat insulation container. It can be suitably used as a transport container, a parts packing material, and a power generation equipment member. As a member for motor vehicles, members, such as a floor panel, a roof, a bonnet, a fender, and an undercover, are mentioned, for example. Examples of the power generation device member include members such as a windmill and a blade for hydroelectric power generation.

  Since the method for producing a fiber-reinforced composite of the present invention has the above-described configuration, a fiber-reinforced composite having excellent mechanical strength, light weight, and appearance can be easily produced.

It is the schematic cross section which showed an example of the manufacturing point of a fiber reinforced composite. It is sectional drawing which showed the fiber reinforced composite_body | complex. It is the schematic cross section which showed another example of the manufacturing procedure of a fiber reinforced composite.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the examples.

(Examples 1-5, Comparative Examples 1-4)
Modified polyethylene terephthalate containing 1,4-cyclohexanedimethanol as part of the diol unit (modified PET, trade name “EN099” manufactured by Eastman, melting point: 238.5 ° C., glass transition temperature Tg: 75.6 ° C.) 100 Modified by containing 1.8 parts by weight of a masterbatch (polyethylene terephthalate content: 60% by weight, talc content: 40% by weight) and 0.26 parts by weight of pyromellitic anhydride containing talc in polyethylene terephthalate The polyethylene terephthalate composition was supplied to a single screw extruder having a diameter of 65 mm and an L / D ratio of 35, and melt kneaded at 290 ° C.

  Next, from the middle of the single screw extruder, butane containing 35% by weight of isobutane and 65% by weight of normal butane was melted so as to have the amount shown in Table 1 with respect to 100 parts by weight of the total amount of modified polyethylene terephthalate and polyethylene terephthalate. It was press-fitted into the modified polyethylene terephthalate composition in a state and uniformly dispersed in the modified polyethylene terephthalate composition.

  Thereafter, after the molten modified polyethylene terephthalate composition was cooled to 280 ° C. at the front end of the extruder, the modified polyethylene terephthalate composition was extruded and foamed from a nozzle of a multi-nozzle mold attached to the front end of the extruder. . The multi-nozzle mold had a nozzle having a diameter of 1 mm at the outlet.

  The modified polyethylene terephthalate extrudate extruded and foamed from the outlet of the nozzle of the multi-nozzle mold was cut with a rotary blade and immediately cooled to produce modified polyethylene terephthalate expanded particles having a substantially spherical re-foaming property. The modified polyethylene terephthalate extrudate was composed of an unfoamed portion immediately after being extruded from the nozzle of the multi-nozzle mold and a foamed portion in the course of foaming continuous with the unfoamed portion. The modified polyethylene terephthalate extrudate was cut at the opening end of the outlet portion of the nozzle, and the modified polyethylene terephthalate extrudate was cut at the unfoamed portion.

  An in-mold foam molding machine equipped with a male and female mold was prepared. In a state where the male mold and the female mold are clamped, a rectangular parallelepiped cavity having an internal dimension of 300 mm in length, 400 mm in width, and 30 mm in height is formed between the male and male molds.

  Modified polyethylene terephthalate foam particles were filled in the mold cavity of the in-mold foam molding machine, and the mold was clamped. After that, water vapor is introduced into the cavity from one mold and passed through the other mold, and the modified polyethylene terephthalate expanded particles with water vapor at a gauge pressure of 0.05 MPa and at a temperature shown in Table 1 in the heating step. Is heated for the heating time shown in Table 1 (first foaming step), and then modified polyethylene terephthalate in a double-sided heating step in which water vapor is introduced into the cavity from both molds and the water vapor supplied into the cavity is not discharged. The modified polyethylene terephthalate foamed particles are re-foamed by heating the foamed particles at a gauge pressure of 0.12 MPa and with the steam having the temperature shown in Table 1 for the heating time shown in Table 1 (second foaming step), Foamed particles obtained by re-foaming terephthalate foamed particles are heat-sealed and integrated by these foaming pressures. After stopping the supply of water vapor and performing a heat retention process for 3 seconds to cool the mold to the atmosphere, the mold was cooled to the temperature shown in Table 1 to cool the foamed molded body (cooling process) Above, the foaming molding was picked out from the metal mold | die. The foamed molded body was aged at the atmospheric temperature shown in Table 1 for the time shown in Table 1 (aging process). Residual foaming agent amount, surface layer crystallinity, apparent density, dimensional change rate under reduced pressure of 100 ° C. and 0.1 MPa (represented simply as “dimensional change rate” in Table 1) Table 1 shows the degree of surface unevenness (in Table 1, “surface unevenness before heating”). Table 1 shows the degree of surface irregularity of the foamed molded product after measuring the dimensional change rate under reduced pressure of 100 ° C. and 0.1 MPa of the foamed molded product (shown as “degree of surface irregularity after heating” in Table 1). It was.

Eight reinforcing fiber base materials (trade name “Pyrofil TR3523M” manufactured by Mitsubishi Rayon Co., Ltd., basis weight: 200 g / m ² , thickness: 0.23 mm) prepared by twilling carbon fibers were prepared. Four of these reinforcing fiber base materials are laminated and reinforced by sequentially superimposing their warp yarn length directions to be 45 °, −45 °, 0 °, and 90 °. Two sets of fiber substrates were prepared. The reinforcing fiber substrates were temporarily fixed using a spray glue 77 manufactured by 3M as a temporary fixing agent. The temporary fixing force between the reinforcing fiber bases was 1.5 N / cm ² . In Table 1, “Temporary fixing force between reinforcing fiber substrates” is expressed as “Temporary fixing force (reinforcing fiber substrates)”. The four reinforcing fiber bases were cut out from a portion where all the reinforcing fiber bases overlapped into a plane rectangular shape of 300 mm in length and 400 mm in width and used as a laminated reinforcing fiber base. The warp yarn length direction is based on the warp yarn length direction of any reinforcing fiber base (0 °), and the clockwise angle is + (plus), counterclockwise. The direction was expressed as-(minus).

  Laminated reinforcing fiber base materials 2 and 2 were laminated on both surfaces of the foam molded body 1 in the thickness direction to produce a laminated body A (lamination step). The laminated reinforcing fiber bases 2 and 2 were temporarily fixed on both surfaces of the foamed molded body 1 using a spray glue 77 manufactured by 3M as a temporary fixing agent. Table 1 shows the temporary fixing force of the laminated reinforcing fiber base material to the foam molded article. In Table 1, “Temporary fixing force of the laminated reinforcing fiber base material relative to the foam molded body” is expressed as “Temporary fixing force (foaming molded body / laminated reinforcing fiber base material)”. In the two laminated reinforcing fiber bases 2 and 2, the reinforcing fiber base having the warp length direction of 90 ° in the reinforcing fiber base is the outermost, and the warp length of the outermost reinforcing fiber base is The foam molded body 1 was laminated on both surfaces so that the vertical directions were perpendicular to each other.

  Next, the layered product A was heated so that the surface temperature became the heating temperature shown in Table 1. As shown in FIG. 1, the male and female molds 31 and 32 were clamped after the laminate A was supplied into the male and female molds 31 and 32. On the other hand, a molten epoxy resin (“DxENATOOL XNR 6809” manufactured by Nagase ChemteX Corp., glass transition temperature Tg: 65.0 ° C.) heated to the temperature shown in Table 1 was prepared.

  The molten epoxy resin is supplied into the cavities 33 of the male and female molds 31 and 32 through a resin supply path (not shown) at an injection pressure of 0.2 MPa, and the epoxy resin is entirely applied to the laminated reinforcing fiber bases 2 and 2. While impregnating the resin, the epoxy resin was spread over the interface between the laminated reinforcing fiber bases 2 and 2 and the foamed molded body 1. The temporary fixing between the laminated reinforcing fiber base and the foamed molded body and the temporary fixing between the reinforcing fiber bases were released with the impregnation of the molten epoxy resin.

  A part of the epoxy resin supplied in the cavity 33 of the male and female molds 31 and 32 was sucked and discharged outside the male and female molds 31 and 32 through a resin discharge path (not shown) using a vacuum pump. Accordingly, the inside of the cavity 33 of the male and female molds 31 and 32 is in a reduced pressure state (impregnation step).

  Next, the male and female molds 31 and 32 are heated to 120 ° C. and held for 90 minutes, and the epoxy resin supplied into the cavity 33 of the male and female molds 31 and 32 is cured. 32 is cooled to 30 ° C., and a fiber reinforced composite B in which fiber reinforced plastic layers 4 and 4 are integrally laminated and integrated with an epoxy resin in which reinforced fibers are cured is laminated on the foamed molded body 1. (Integration process). The fiber reinforced plastic layer 4 of the fiber reinforced composite B was impregnated with an epoxy resin in the amount shown in Table 1.

(Example 6)
A foamed molded article was produced in the same manner as in Example 4. On each surface having dimensions of 300 mm in length and 400 mm in width in the foam-molded product, straight resin circulation grooves having a width of 1 mm and a depth of 5 mm extending in the vertical direction were formed at intervals of 10 mm in the horizontal direction. A cell cross section of the foamed molded product was exposed on the surface of the groove for resin circulation. A fiber-reinforced composite B was produced in the same manner as in Example 4 except that this foamed molded product was used.

(Example 7)
An in-mold foam molding machine equipped with a male and female mold was prepared. In a state where the male mold and the female mold are clamped, a rectangular parallelepiped cavity having an internal dimension of 300 mm in length, 400 mm in width, and 30 mm in height is formed between the male and male molds. In the cavity formed between the male and female molds of the in-mold foam molding machine, a straight groove-forming convex portion extending in the vertical direction having a width of 1 mm and a height of 5 mm is formed on the inner surface formed 300 mm long × 400 mm wide. It was formed at intervals of 10 mm in the lateral direction.

  A foam-molded article was produced using the in-mold foam molding machine. On each of the surfaces having dimensions of 300 mm in length and 400 mm in width in the foamed molded product, straight resin flow grooves having a width of 1 mm and a depth of 5 mm extending in the vertical direction were formed at intervals of 10 mm in the horizontal direction. . Bubbles in the foamed molded product were not exposed in the groove for resin distribution. A fiber-reinforced composite B was produced in the same manner as in Example 4 except that this foamed molded product was used.

(Examples 8 and 9)
A 300 mm long, 400 mm wide, 30 mm high rectangular molded foam containing an acrylic resin and having an unfoamed skin on its surface (expanding ratio 10 times, manufactured by Sekisui Plastics Co., Ltd. 1000 grade ") was used as the foam molded body, and the laminate A was heated so that the surface temperature thereof became the temperature shown in Table 1 and then supplied into the male and female molds 31 and 32. In the same manner as in Example 5, a fiber-reinforced composite B was produced.

(Comparative Example 5)
A 300 mm long, 400 mm wide, 30 mm high cuboid foam molded article containing an acrylic resin and having an unfoamed skin on its surface (foaming magnification 10 times, manufactured by Sekisui Plastics Co., Ltd., product name “Formac # 1000 A fiber-reinforced composite B was produced in the same manner as in Example 8 except that “grade”) was used as the foam molded article.

  In Examples and Comparative Examples, the movement amount of the reinforcing fiber in the impregnation process is shown in Table 1. The strength uniformity and surface property of the fiber reinforced composites obtained in the examples and comparative examples were measured in the following manner, and the results are shown in Table 1. The resin injection time in the impregnation process was measured and evaluated in the following manner. In Examples 6 and 7, a groove for resin distribution was formed on the surface of the foamed molded product, and the resin injection time was shortened because the epoxy resin was easily distributed.

(Strength uniformity)
A plane rectangular test piece having a length of 150 mm × width of 25 mm is cut out from any 15 locations of the fiber reinforced composite, and each test piece is tested under the conditions of a test speed of 10 mm / min and a support jig 5R in accordance with JIS K6767. A bending test was performed to measure the maximum point load. The strength uniformity was calculated based on the maximum point load of each test piece, and evaluated based on the following criteria.
Strength uniformity (%) = 100 × (maximum point load at maximum value−maximum point load at minimum value)
/ The average value of the maximum point load ○ was less than 10%.
Δ: 10% or more and less than 20%.
X: 20% or more.

(Surface property)
The surface of both fiber reinforced plastic layers of the fiber reinforced composite was visually observed over the entire surface, and the number of recesses having a size of 0.1 mm or more was counted. Based on the number of recesses obtained, the number of recesses present per 10 cm ² was calculated and evaluated based on the following criteria.
○: Less than 3
Δ: 3 or more and less than 8.
X ... 8 or more.

(Resin injection time)
The time when the epoxy resin started to be discharged from the resin discharge path after the injection of the epoxy resin into the cavity 33 of the male and female molds 31 and 32 was measured and evaluated based on the following criteria.
○: Less than 3 minutes.
Δ: 3 minutes or more and less than 6 minutes.
X ... 6 minutes or more.

DESCRIPTION OF SYMBOLS 1 Foam molding 2 Reinforcing fiber 4 Fiber reinforced plastic layer 5 Flexible film A Laminate B Fiber reinforced composite

Claims (4)

Lamination process for producing a laminate by laminating reinforcing fibers on the surface of the foam molded body, an impregnation process for supplying a synthetic resin to the reinforcing fibers of the laminate and impregnating the reinforcing fibers with the synthetic resin, and the synthesis A fiber including an integration step in which the reinforcing fiber impregnated with the synthetic resin is made into a fiber-reinforced plastic layer by solidifying or curing the resin, and the fiber-reinforced plastic layer is laminated and integrated on the surface of the foamed molded body In the laminated body before the impregnation step, the reinforcing fiber is temporarily fixed to the surface of the foamed molded body with a temporary fixing force of ¹ to 30 N / cm2 , and the impregnation is performed. the temporary fixing by the synthetic resin impregnated into the reinforcing fibers is released in step, the moving amount of the reinforcing fibers in the surface direction of the foam moldings in the impregnation step is 0. Method for producing a fiber-reinforced composite, wherein the 5 to 10%. 2. The method for producing a fiber-reinforced composite according to claim 1 , wherein a dimensional change rate under reduced pressure of 100 ° C. and 0.1 MPa in the foamed molded product is −2 to 10%. 3. The synthetic resin at 40 to 90 ° C. is supplied to the reinforcing fiber after the foamed molded body is heated so that its surface temperature becomes 10 to 90 ° C. in the impregnation step. A method for producing a fiber-reinforced composite. In the impregnation process, according to claim 1 to 3, characterized and the surface temperature of the foamed molded body before impregnating the synthetic resin to reinforcing fibers, the difference between the temperature of the supplied synthetic resin into the reinforcing fibers is 50 ° C. or less The manufacturing method of the fiber reinforced composite of any one of these.

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