JP6600982B2 - FIBER-REINFORCED PLASTIC MOLDED BODY, ITS MANUFACTURING METHOD, AND LAMINATE - Google Patents

Description

  The present invention relates to a fiber-reinforced plastic molded body, a method for producing the same, and a laminate.

Carbon fiber reinforced plastic moldings containing reinforced fibers and matrix resin compositions are widely used in industrial applications such as aircraft and automobiles due to their excellent mechanical properties, etc. It is coming. For example, there is known a fiber-reinforced plastic molded body formed by heating and pressurizing a prepreg laminate in which a plurality of sheet-like prepreg base materials in which reinforcing fibers are impregnated with a matrix resin composition are laminated.
As the matrix resin composition, a thermosetting resin composition containing a phenol resin, a melamine resin, a bismaleimide resin, an unsaturated polyester resin, an epoxy resin, or the like is often used because of its excellent impregnation and heat resistance. . Among these, epoxy resin compositions are widely used because a fiber-reinforced plastic molded article having excellent heat resistance and moldability and higher mechanical strength can be obtained.

  Moreover, as a fiber reinforced plastic molded object, the prepreg laminated body is used for the purpose of suppressing the fiber existing near the surface from being seen through (that is, preventing the fiber from being sufficiently embedded in the resin layer and being exposed). There is known a fiber-reinforced plastic molded body that is molded by heating and pressing in a state where a resin film containing reinforcing fibers and a thermosetting resin composition is further laminated on the surface. The resin film has a higher ratio of the thermosetting resin composition and a lower ratio of reinforcing fibers than the prepreg base material.

  As a method for producing a fiber-reinforced plastic molded body, for example, a method using an autoclave (Patent Document 1), a method using a vacuum bag (Patent Document 2), a compression molding method (Patent Document 3), and the like are known. However, in these methods, when the prepreg laminate is cured by heating and pressing, heating at 160 ° C. or higher for about 2 to 6 hours is required until curing, and energy consumption is large and productivity is low.

High cycle press molding is known as a molding method frequently used for automobile applications (Patent Document 4). In high cycle press molding, in order to enable mass production of products, curing is performed in a short time of about several minutes to several tens of minutes at about 100 to 150 ° C. under high pressure.
However, when molding is performed by laminating a resin film on the surface of the prepreg laminate, the viscosity of the thermosetting resin composition contained in the resin film is decreased due to an increase in temperature under high pressure. The conductive resin composition may flow out excessively from the edge portion of the mold. As described above, when the thermosetting resin composition on the surface excessively flows out of the mold, fibers are exposed due to resin withering on the surface of the obtained molded body, or fiber meandering due to excessive flow of the resin occurs. Deterioration of the appearance such as In this case, even if the molded body surface is painted, the appearance is poor.

JP-A-10-128778 JP 2002-159613 A JP-A-10-95048 International Publication No. 2004/48435

  The present invention provides a fiber reinforced plastic molded article in which appearance defects such as resin withering and fiber meandering on the surface are suppressed even when high cycle press molding is adopted, and fibers on the surface are suppressed from being seen through. It aims at providing the manufacturing method of the fiber reinforced plastic molding which can be manufactured. Further, the present invention relates to a fiber reinforced plastic molded body in which occurrence of poor appearance such as resin withering and fiber meandering on the surface and suppression of fiber see-through are suppressed, and a laminate used for the production of the fiber reinforced plastic molded body The purpose is to provide.

The manufacturing method of the fiber reinforced plastic molding of this invention is a method which has the following lamination process and a formation process.
Lamination process: The following thermoplastic resin particles (on the surface of at least one of the prepreg laminates obtained by laminating a plurality of sheet-like prepreg substrates in which the reinforcing fiber substrate (A) is impregnated with the thermosetting resin composition (B) The process of obtaining the laminated body by laminating | stacking the resin film formed with the thermosetting resin composition (C) containing c1).
Molding step: a step of heating and pressurizing the laminate with a mold to obtain a fiber-reinforced plastic molded body.
Thermoplastic resin particles (c1): particles containing at least one thermoplastic resin selected from the group consisting of polyethersulfone, polyphenylene sulfide, polyetheretherketone, polyimide and polyetherimide.

The resin film preferably contains a reinforcing fiber base (D) having a fiber basis weight of 50 g / m ² or less.
The thermoplastic resin particles (c1) preferably have an average particle size of 0.1 to 100 μm.
The reinforcing fiber substrate (D) is preferably a nonwoven fabric made of reinforcing fibers.
The glass transition temperature of the thermoplastic resin particles (c1) is preferably equal to or higher than the mold temperature in the molding step.
The thermoplastic resin particles (c1) are preferably polyethersulfone particles.
The thermosetting resin composition (C) preferably contains an epoxy resin.
The thermosetting resin composition (B) preferably contains an epoxy resin.
The method for producing a fiber-reinforced plastic according to the present invention further includes a shaping step of shaping the laminate obtained in the lamination step to obtain a preform prior to the molding step, and the laminate in the molding step The preform may be used as

The laminate of the present invention is formed on the surface of at least one of the prepreg laminates obtained by laminating a plurality of sheet-like prepreg substrates in which the reinforcing fiber substrate (A) is impregnated with the thermosetting resin composition (B). It is a laminate in which a resin film formed of a thermosetting resin composition (C) containing the plastic resin particles (c1) is further laminated.
The fiber-reinforced plastic molded body of the present invention is a fiber-reinforced plastic molded body formed by heating and pressing the laminate of the present invention.

According to the method for producing a fiber-reinforced plastic molded body of the present invention, even when high cycle press molding is employed, it is possible to suppress appearance defects such as resin withering and fiber meandering on the surface, and fibers on the surface can be seen through. It is possible to produce a fiber-reinforced plastic molded product in which this is suppressed.
By using the laminate of the present invention, it is possible to obtain a fiber-reinforced plastic molded product in which appearance defects such as resin withering and fiber meandering on the surface and fiber see-through are suppressed.
In the fiber-reinforced plastic molded body of the present invention, occurrence of poor appearance such as resin withering and fiber meandering on the surface, and fiber see-through are suppressed.

It is sectional drawing which showed an example of the laminated body used for the manufacturing method of the fiber reinforced plastic molding of this invention. It is sectional drawing which showed an example of the shaping | molding process in the manufacturing method of the fiber reinforced plastic molding of this invention. It is sectional drawing which showed an example of the fiber reinforced plastic molding of this invention.

[Production method of fiber reinforced plastic molding]
The manufacturing method of the fiber reinforced plastic molding of this invention has the following lamination process and a shaping | molding process.
Lamination process: Thermoplastic resin particles (c1) on at least one surface of a prepreg laminate in which a plurality of sheet-like prepreg substrates in which the reinforcing fiber substrate (A) is impregnated with the thermosetting resin composition (B) are laminated. The process of laminating | stacking the resin film formed with the thermosetting resin composition (C) containing), and obtaining a laminated body.
Molding step: a step of heating and pressurizing the laminate with a mold to obtain a fiber-reinforced plastic molded body.

(Lamination process)
In the present invention, as a material of the reinforced fiber plastic molded body, a sheet-like prepreg base material in which a reinforced fiber base material (A) is impregnated with a thermosetting resin composition (B), and thermoplastic resin particles (c1) are used. The resin film formed with the thermosetting resin composition (C) to contain is used.
In the lamination step, a resin film is laminated on at least one surface of the prepreg laminate. That is, in the present invention, the resin film may be laminated only on one side of the prepreg laminate (ie, the surface of one outermost layer), or the resin film is laminated on both sides of the prepreg laminate (ie, the surfaces of both outermost layers). May be.

For example, when laminating a resin film only on the upper surface of a prepreg laminate, a plurality of sheet-like prepreg base materials are laminated to form a prepreg laminate, and a resin film is further laminated on the outermost surface of the prepreg laminate. Let it be the body.
The operation of laminating a plurality of prepreg base materials and the operation of laminating the prepreg laminate and the resin film may be performed outside the mold used in the molding process, or may be performed within the mold.

<Laminated body>
In the laminate used in the present invention, a resin film is laminated on at least one surface of a prepreg laminate in which a plurality of prepreg substrates are laminated. For example, as shown in FIG. 1, a resin film 14 is further laminated on a prepreg laminate 12 in which a plurality of sheet-like prepreg base materials 10 are laminated to form a laminate 1.

≪Prepreg base material≫
The prepreg base material used in the present invention is a sheet-like prepreg base material in which the reinforcing fiber base material (A) is impregnated with the thermosetting resin composition (B).
The reinforcing fiber constituting the reinforcing fiber base (A) is not particularly limited, and for example, inorganic fibers, organic fibers, metal fibers, or hybrid fibers that combine these can be used.
Examples of the inorganic fiber include carbon fiber, graphite fiber, silicon carbide fiber, alumina fiber, tungsten carbide fiber, boron fiber, and glass fiber. Examples of the organic fibers include aramid fibers, high density polyethylene fibers, other general nylon fibers, and polyester fibers. Examples of metal fibers include fibers such as stainless steel and iron, and carbon fibers coated with metal may be used. Among these, carbon fibers are preferable in consideration of mechanical properties such as strength of the reinforced fiber plastic molded body.

The reinforcing fiber of the reinforcing fiber base (A) may be a long fiber or a short fiber, and is preferably a long fiber from the viewpoint of excellent rigidity. As a form of the reinforcing fiber base, a form in which a large number of long fibers are aligned in one direction to form a UD sheet (unidirectional sheet), a form in which long fibers are woven to form a cloth material (woven fabric), and a non-woven fabric made of short fibers And the like.
Examples of the cloth weaving method include plain weave, twill weave, satin weave, and triaxial weave.

Fiber basis weight of the reinforcing fiber base material (A) is preferably from ^{50~800g / m 2, 75~300g / m} 2 is more preferable. If the fiber basis weight of the reinforcing fiber substrate (A) is at least the lower limit value, it is preferable because the number of laminated layers required for obtaining a molded product having a desired thickness is not increased. If the fiber basis weight of the reinforcing fiber base (A) is not more than the upper limit value, it is preferable because a prepreg base material in a good impregnation state is easily obtained.

Examples of the thermosetting resin (b1) used in the thermosetting resin composition (B) include epoxy resins, vinyl ester resins, unsaturated polyester resins, polyimide resins, maleimide resins, and phenol resins. When carbon fiber is used as the reinforcing fiber, an epoxy resin or a vinyl ester resin is preferable, and an epoxy resin is particularly preferable from the viewpoint of adhesiveness with the carbon fiber.
As the thermosetting resin (b1), one type may be used alone, or two or more types may be used in combination.

The thermosetting resin composition (B) preferably contains a curing agent in addition to the thermosetting resin (b1). For example, when the thermosetting resin (b1) is an epoxy resin, the curing agent is preferably dicyandiamide or an imidazole curing agent.
The thermosetting resin composition (B) preferably further contains a curing aid. For example, when the thermosetting resin (b1) is an epoxy resin, a urea compound is preferable as the curing aid.
Further, the thermosetting resin composition (B) may contain additives such as inorganic fine particles.

The viscosity at 30 ° C. of the thermosetting resin composition (B) is preferably 1.0 × 10 ^{2 to} 1.0 × 10 ⁵ Pa · s, and 5.0 × 10 ^{2 to} 9.8 × 10 ⁴ Pa · s. s is more preferable, and 1.0 × 10 ^{3 to} 9.7 × 10 ⁴ Pa · s is more preferable. If the viscosity of the thermosetting resin composition (B) is equal to or higher than the lower limit, the handleability of the prepreg base material is excellent, and operations such as preparation, lamination, and molding of the prepreg base material are facilitated. If the viscosity of the thermosetting resin composition (B) is not more than the upper limit value, the reinforcing fiber base (A) can be easily impregnated with the thermosetting resin composition (B), and it is not necessary to heat excessively during the impregnation. . Moreover, the draping property of the prepreg base material is not easily impaired.

  As for the minimum viscosity in the temperature rising viscosity measurement which heats up a thermosetting resin composition (B) at 2 degree-C / min, 1.0-50 Pa.s is preferable. If the minimum viscosity is within the above range, the flow rate of the thermosetting resin composition (B) at the time of molding can be easily controlled within an appropriate range. If the minimum viscosity is not less than the lower limit of the above range, excessive flow of the thermosetting resin composition (B) at the time of molding is easily suppressed, and appearance defects such as irregularities are less likely to occur on the surface of the molded body. If the minimum viscosity is less than or equal to the upper limit of the above range, it is easy to suppress the flow amount of the thermosetting resin composition (B) from being excessively reduced, and the thermosetting resin composition is formed in every corner of the fiber-reinforced plastic molded body. Good (B) is easy to get around.

  As a prepreg base material, for example, a cross prepreg base material in which a reinforcing fiber base material (A) in which reinforcing fibers are woven in biaxial directions is impregnated with a thermosetting resin composition (B), the reinforcing fibers are in one direction. Examples thereof include a prepreg base material (UD prepreg base material) in which the aligned reinforcing fiber base material (A) is impregnated with the thermosetting resin composition (B). In addition, the reinforcing fiber base (A) in which the reinforcing fibers are aligned in one direction is cut into the prepreg base material impregnated with the thermosetting resin composition (B), and the reinforcing fibers in the prepreg base material are cut short. You may use what you did.

  The fiber length of the reinforcing fiber in the prepreg base material is preferably 12.7 mm or more, and more preferably 25.4 mm or more. If the fiber length of the reinforcing fiber is equal to or more than the lower limit value, the mechanical properties of the fiber-reinforced plastic molded body are likely to be sufficiently high.

The laminated structure of the prepreg laminate is not particularly limited. For example, when using a UD prepreg base material, the structure which laminated | stacked each UD prepreg base material so that the fiber axis of the reinforced fiber of the UD prepreg base material adjacent on the upper and lower sides may be mentioned. In the prepreg laminate, only the same type of prepreg base material may be laminated, or different types of prepreg base materials may be laminated.
The number of laminated prepreg base materials is not particularly limited, and can be appropriately determined according to required characteristics.

≪Resin film≫
The resin film used for this invention is a resin film formed with the thermosetting resin composition (C) containing a thermoplastic resin particle (c1).
The thermoplastic resin particles (c1) are particles containing at least one thermoplastic resin selected from the group consisting of polyethersulfone, polyphenylene sulfide, polyetheretherketone, polyimide and polyetherimide.

The average particle diameter of the thermoplastic resin particles (c1) is preferably 0.1 to 100 μm, and more preferably 1 to 50 μm. If the average particle diameter of the thermoplastic resin particles (c1) is not less than the lower limit value, excessive flow of the thermosetting resin composition (C) during molding can be easily suppressed. As a result, it becomes easy to suppress appearance defects such as resin withering and fiber meandering on the surface of the obtained fiber reinforced plastic molding. If the average particle diameter of the thermoplastic resin particles (c1) is not more than the upper limit value, it is easy to obtain a reinforced fiber plastic molded article having excellent surface smoothness.
The average particle diameter of the thermoplastic resin particles (c1) means a particle diameter (D50) having a cumulative frequency of 50% on a volume basis measured by a laser diffraction method.

  The glass transition temperature (Tg) of the thermoplastic resin particles (c1) is preferably equal to or higher than the mold temperature in the molding step, more preferably 20 ° C. higher than the mold temperature, and 40 ° C. higher than the mold temperature. More preferably. Considering a general mold temperature when producing a fiber-reinforced plastic molded body, the Tg of the thermoplastic resin particles (c1) is preferably 140 ° C. or higher, and more preferably 180 ° C. or higher. If the Tg of the thermoplastic resin particles (c1) is equal to or higher than the lower limit, an effect of suppressing excessive flow of the thermosetting resin composition (C) at the time of molding can be more easily obtained, and the fiber-reinforced plastic molded article can be obtained. Appearance defects such as resin withering and fiber meandering are less likely to occur on the surface.

  As the thermoplastic resin particles (c1), polyethersulfone particles are particularly preferable from the viewpoint of heat resistance.

As a thermosetting resin (c2) used for a thermosetting resin composition (C), the same thing as what was mentioned by the thermosetting resin (b1) is mentioned, for example.
As a thermosetting resin (c2) used for a thermosetting resin composition (C), an epoxy resin is preferable from the point of heat resistance and mechanical strength.

The thermosetting resin composition (C) preferably contains a curing agent in addition to the thermosetting resin (c2). For example, when the thermosetting resin (c1) is an epoxy resin, an imidazole-based curing agent is preferable as the curing agent.
The thermosetting resin composition (C) preferably further contains a curing aid. For example, when the thermosetting resin (c1) is an epoxy resin, a urea compound is preferable as the curing aid.
Further, the thermosetting resin composition (C) may contain additives such as a dispersant for dispersing the thermoplastic resin particles (c1) and inorganic fine particles.

  The ratio of the mass of the thermoplastic resin particles (c1) to the total mass of the thermoplastic resin particles (c1) and the thermosetting resin (c2) in the thermosetting resin composition (C) is preferably 3 to 50% by mass. 5 to 35% by mass is more preferable. If the ratio of the thermoplastic resin particles (c1) is equal to or more than the lower limit value, excessive flow of the thermosetting resin composition (C) during molding is suppressed, and the molded body surface is subjected to resin withering, fiber meandering, and the like. It is easy to obtain the effect of suppressing appearance defects. When the ratio of the thermoplastic resin particles (c1) is not more than the above upper limit value, handleability such as tackiness is preferable.

The viscosity at 30 ° C. of the thermosetting resin composition (C) is preferably 1.0 × 10 ^{2 to} 1.0 × 10 ⁵ Pa · s, and 5.0 × 10 ^{2 to} 9.8 × 10 ⁴ Pa · s. s is more preferable, and 1.0 × 10 ^{3 to} 9.7 × 10 ⁴ Pa · s is more preferable. If the viscosity of a thermosetting resin composition (C) is more than a lower limit, the handleability of a resin film will be excellent. If the viscosity of a thermosetting resin composition (C) is below an upper limit, it will become easy to impregnate a reinforcing fiber base material (D) with a thermosetting resin composition (C).

  As for the minimum viscosity in the temperature rising viscosity measurement which heats up a thermosetting resin composition (C) at 2 degree-C / min, 1.0-50 Pa.s is preferable. If the minimum viscosity is within the above range, the flow rate of the thermosetting resin composition (C) during molding can be easily controlled within an appropriate range. If the minimum viscosity is not less than the lower limit of the above range, excessive flow of the thermosetting resin composition (C) at the time of molding is easily suppressed, and appearance defects such as resin withering and fiber meandering are more likely to occur on the surface of the molded body. It becomes difficult to occur. If the minimum viscosity is not more than the upper limit of the range, it is easy to suppress the flow rate of the thermosetting resin composition (C) from being excessively reduced.

The resin film preferably contains a reinforcing fiber substrate (D) having a fiber basis weight of 50 g / m ² or less. Thereby, the mechanical strength can be further increased while suppressing the occurrence of appearance defects such as resin withering and fiber meandering on the surface of the fiber-reinforced plastic molded body.

It does not specifically limit as a reinforcing fiber which comprises a reinforcing fiber base material (D), For example, the same thing as what was mentioned by the reinforcing fiber base material (A) is mentioned.
The reinforcing fiber base is in a state where a long one is wound into a roll shape, and is often used while being drawn out from the state. In this case, the reinforcing fiber base is easily contracted in the width direction due to the tension when drawn out from the roll state. As the reinforcing fibers of the reinforcing fiber substrate (D), it is preferable to use reinforcing fibers that are less likely to shrink in the width direction and have a low water absorption even when used from a roll-like state. Specifically, carbon fibers and glass fibers are preferable as the reinforcing fibers of the reinforcing fiber substrate (D).

The reinforcing fibers of the reinforcing fiber base (D) may be long fibers or short fibers.
The form of the reinforcing fiber base (D) includes a form in which a large number of long fibers are aligned in one direction to form a UD sheet (unidirectional sheet), a form in which long fibers are woven to form a cloth material (woven fabric), and short fibers The form made into the nonwoven fabric which consists of etc. is mentioned. Especially, the nonwoven fabric which consists of a reinforced fiber is preferable as a reinforced fiber base material (D) from the point which is easy to obtain the fiber reinforced plastic excellent in surface smoothness.

The fiber basis weight of the reinforcing fiber base material (D) is that the reinforcing fiber base material (D) used for the prepreg base material is easy to suppress the see-through of the reinforcing fiber base material (D) on the surface of the molded body. Is preferably smaller. The upper limit value of the fiber basis weight of the reinforcing fiber base (D) is 50 g / m ² , and preferably 30 g / m ² .
The lower limit value of the fiber basis weight of the reinforcing fiber base (D) is preferably 1 g / m ² from the viewpoint of easy production of the reinforcing fiber base (D).

  When the resin film contains the reinforcing fiber base (D), the fiber length of the reinforcing fiber in the resin film is preferably 5 to 50 mm, and more preferably 10 to 30 mm. If the fiber length of the reinforcing fiber is equal to or more than the lower limit value, the mechanical properties of the fiber-reinforced plastic molded body are likely to be sufficiently high. If the fiber length of the reinforcing fiber is not more than the above upper limit value, the moldability of the laminate is improved.

When the resin film contains the reinforcing fiber substrate (D), the fiber volume content (Vf) in the resin film is preferably 50% by volume or more, and more preferably 70% by volume or more. When Vf is equal to or higher than the lower limit, the mechanical properties of the fiber-reinforced plastic molded body are likely to be sufficiently high.
In addition, Vf of a resin film means the value measured by the method similar to Vf of a prepreg base material.

When the resin film contains the reinforcing fiber substrate (D), the resin content in the resin film is preferably larger than that of the reinforcing fiber substrate (D). In this case, the resin content in the resin film is preferably ^{50~500g / m 2, 100~300g / m} 2 is more preferable. If the resin content in the resin film is equal to or higher than the lower limit, the reinforcing fiber base (D) is hardly exposed on the surface of the molded body, and a fiber-reinforced plastic molded body having excellent surface smoothness is easily obtained. If resin content in a resin film is below an upper limit, handling of a resin film will become easy.

  The thickness of the resin film is preferably 20 to 400 μm, and more preferably 40 to 300 μm. If the thickness of a resin film is more than a lower limit, it is excellent in the fiber-shielding property in the molded object surface, and preferable. If the thickness of the resin film is less than or equal to the upper limit value, it is preferable because the thickness of the molded body does not increase more than necessary.

The number of resin films laminated on one surface of the prepreg laminate is not particularly limited, and may be one or may be two or more.
In addition, the resin film which does not contain a reinforced fiber base material (D) may be sufficient as the resin film used for this invention.

[Molding process]
The laminated body obtained in the laminating step is heated and pressed with a mold to obtain a fiber-reinforced plastic molded body.
As a method for forming a laminate using a mold, a known forming method can be employed, and examples thereof include autoclave forming, oven forming, internal pressure forming, and press forming.
Compared to other molding methods, press molding makes it easier to obtain a fiber-reinforced plastic molded body having a resin layer formed from a resin film on the surface, but the molding pressure is high and the resin flows out of the mold. It tends to be easy to do. Therefore, the present invention that can suppress the resin outflow from the mold during molding is more effective when press molding is employed in the molding process, and is particularly effective when high cycle press molding is employed.

  For example, the case where the laminated body 1 is press-molded with the metal mold | die 100 illustrated in FIG. 2 is demonstrated. The mold 100 includes a lower mold 110 provided with a convex portion 112 on the upper surface side, and an upper mold 120 provided with a concave portion 122 on the lower surface side. When the upper mold 120 is brought close to the lower mold 110 and the mold 100 is closed, a cavity having a shape complementary to the shape of the target fiber-reinforced plastic molded body is formed between the convex portion 112 and the concave portion 122 in the mold 100. Is to be formed.

As shown in FIG. 2A, the laminate 1 is disposed on the convex portion 112 of the lower mold 110 in the heated mold 100 so that the resin film 14 is on the upper side.
Next, as shown in FIG. 2B, the upper mold 120 is brought close to the lower mold 110 to close the mold 100, and the laminate 1 is molded by heating and pressing. By being heated while being pressed by the mold 100, the thermosetting resin composition (B) and the thermosetting resin composition (C) in the laminate 1 are cured while flowing. At this time, since the thermoplastic resin particles (c1) are contained in the resin film 14, it is suppressed that the thermosetting resin composition (C) flows excessively. Outflow of the curable resin composition (C) is suppressed (that is, excessive outflow can be prevented).
After curing, as shown in FIG. 2 (c), the mold 100 is opened and the fiber-reinforced plastic molded body 2 is taken out.

As the molding conditions, known molding conditions can be adopted except that the above-described laminate is used.
100-180 degreeC is preferable and the mold temperature at the time of shaping | molding has more preferable 120-160 degreeC.
The surface pressure during molding is preferably 1 to 15 MPa, and more preferably 4 to 10 MPa.
The molding time is preferably 1 to 15 minutes, and more preferably 2 to 5 minutes.

[Shaping process]
In the manufacturing method of the fiber reinforced plastic of this invention, you may have further the shaping | molding process which shapes the laminated body obtained at the lamination process and obtains a preform prior to a formation process. That is, in the manufacturing method of the fiber reinforced plastic of this invention, the method of performing a lamination process, a shaping process, and a shaping | molding process in this order may be sufficient. In this case, a fiber reinforced plastic is manufactured by shaping the laminate obtained in the lamination step in the shaping step to obtain a preform, and then molding the preform by heating and pressing in the molding step.

  The method for shaping the laminate is not particularly limited as long as it can be shaped into an intermediate shape based on the shape of the target fiber-reinforced plastic molded article, and a known method is adopted except that the laminate of the present invention is used. Can do.

In the method for producing a fiber-reinforced plastic molded body of the present invention described above, a resin film formed of a thermosetting resin composition (C) containing thermoplastic resin particles (c1) is laminated on the surface of a prepreg laminate. The laminated body used is used. By containing the thermoplastic resin particles (c1) in the resin film, the thermosetting resin composition (C) is suppressed from excessively flowing in the mold during molding. Thereby, even if it is a case where high cycle press molding is employ | adopted, it is suppressed that the thermosetting resin composition (C) contained in a resin film flows out of a metal mold | die. Therefore, appearance defects such as resin withering and fiber meandering are suppressed from occurring on the surface of the obtained fiber-reinforced plastic molded body.
Further, in the method for producing a fiber reinforced plastic molded body of the present invention, since the resin film is laminated on the surface of the prepreg laminate, the fiber may be seen through the surface of the obtained fiber reinforced plastic molded body. It is suppressed.

[Fiber-reinforced plastic molding]
The fiber-reinforced plastic molded body of the present invention is a fiber-reinforced plastic molded body molded by heating and pressing the above-described laminate.
The fiber-reinforced plastic molded body of the present invention includes a composite material portion formed from a prepreg laminate, and a resin layer formed from a resin film on the surface of the composite material portion. The said composite material part contains the hardened | cured material of a reinforced fiber base material (A) and a thermosetting resin composition (B). The said resin layer contains the hardened | cured material of a thermosetting resin composition (C), and the reinforced fiber base material (D) used as needed.
The shape and size of the fiber-reinforced plastic molded body of the present invention are not particularly limited and can be appropriately determined according to the application.

For example, a fiber reinforced plastic molded body 2 obtained by molding the laminated body 1 with a mold 100 includes a composite material portion 20 formed from a prepreg laminated body 12 and a surface of the composite material portion 20 as shown in FIG. And a resin layer 22 formed from the resin film 14. The composite material part 20 contains the hardened | cured material of a reinforced fiber base material (A) and a thermosetting resin composition (B). The resin layer 22 contains a cured product of the thermosetting resin composition (C) and a reinforcing fiber base (D) used as necessary.
Further, the fiber reinforced plastic molded body 2 of this example has a mode in which the side portion 4 extends vertically from both ends of the flat plate portion 3 toward the opposite side to the resin layer 22.

  In the fiber-reinforced plastic molded body of the present invention, since the thermosetting resin composition (C) contained in the resin film during molding is suppressed from excessively flowing, appearance such as resin withering and fiber meandering on the surface Generation | occurrence | production of a defect and fiber see-through are suppressed.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited by the following description.
[Measurement of average particle size]
The thermoplastic resin particles are dispersed in the air, and the volume-based particle size distribution is measured by laser diffraction using an AEROTRAC SPR MDEL: 7340 manufactured by Nikkiso Co., Ltd., and the particle size (D50) having a cumulative frequency of 50% in the particle size distribution. ) As the average particle diameter of the thermoplastic resin particles.

[Measurement of viscosity of resin composition]
The viscosity of the resin composition was measured under the following measurement conditions.
Apparatus: Rheometer (manufactured by TA Instruments, "VAR-100"),
Plate used: 25φ parallel plate,
Plate gap: 0.5mm,
Measurement frequency: 10 rad / sec,
Temperature increase rate: 2 ° C / min,
Measurement start temperature: 30 ° C.
Stress: 300 Pa.

[Measurement and evaluation of resin flow rate]
The mass of the laminate before molding in each example is M ₀ (g), and the mass of the fiber-reinforced plastic molded body excluding burrs after molding is M ₁ (g). ) Was calculated.
Resin flow rate (%) = [(M ₀ −M ₁ ) / M ₀ ] × 100
(Evaluation criteria)
The resin flow was evaluated according to the following criteria.
○: Resin flow rate is less than 2%.
X: The resin flow rate is 2% or more.

[Evaluation of paint appearance (after wet heat test)]
The coating appearance evaluation was performed as follows.
The surface of the molded body was coated with a thickness of about 80 μm, and the coating film surface after being maintained for 240 hours under the conditions of 50 ° C. and 95% RH was visually evaluated.
(Evaluation criteria)
The coating appearance evaluation was performed according to the following criteria.
○: No fiber sheer is observed.
X: The transparency of a fiber is recognized.

[Raw materials]
The raw materials used in this example are shown below.
(Thermosetting resin (c2))
c2-1: Epoxy resin A (viscosity (90 ° C.): 1.3 Pa · s).
c2-1: Epoxy resin B (viscosity (30 ° C.): 5.0 Pa · s).

(Thermoplastic resin particles (c1))
c1-1: Polyethersulfone particles (product name “Udtrazone E2020SR micro”, manufactured by BASF, average particle size (D50): 22 μm).

(Other thermoplastic resin particles (for comparison))
x-1: Phenoxy resin particles (product name “PKHP-80”, manufactured by InChem, average particle diameter (D50): 60 μm).
x-2: Polyamide 12 particles (product name “Vestosint 2158”, manufactured by Evonik Industries AG, average particle size (D50): 21 μm).
x-3: Acrylic resin particles (product name “LP-3121”, manufactured by Mitsubishi Rayon Co., Ltd., average particle diameter (D50): 70 μm).

(Thermoplastic resin (for comparison))
y-1: Polyethersulfone (product name “Ultrasone E2020SR micro”, manufactured by BASF, dissolved in epoxy resin and used).

(Curing agent)
e-1: 3- (3,4-dichlorophenyl) -1,1-dimethylurea (DCMU) (product name “DCMU-99”, manufactured by Hodogaya Chemical Co., Ltd.).
e-2: Imidazole-based epoxy resin curing agent (product name “Novacure HX3722”, manufactured by Asahi Kasei E-Materials).
e-3: Imidazole-based epoxy resin curing agent (product name “CURESOL 2PHZ-PW”, manufactured by Shikoku Kasei Co., Ltd.).

[Example 1]
95 parts by mass of thermosetting resin (c2-1) and 12.5 parts by mass of thermosetting resin (c2-2) were put into a melting pot, heated to 80 ° C., mixed, and then cooled to about 60 ° C. . Furthermore, 5 parts by mass of thermoplastic resin particles (c1-1), 5 parts by mass of curing agent (e-1), 10 parts by mass of curing agent (e-2), and 5 parts by mass of curing agent (e-3) And stirred and mixed at 60 ° C. to obtain a thermosetting resin composition (C-1).
Subsequently, the thermosetting resin composition (C-1) was apply | coated on the release paper using the multicoater M-500 type | mold made from Hirano tech seed, and the sheet | seat whose resin content is 150 g / m < ² > was obtained.
Next, the sheet peeled from the release paper was impregnated into a glass fiber nonwoven fabric (10 g / m ² , manufactured by H & V) to obtain a resin film.
The resin film was placed on the upper surface of a prepreg laminate in which five pyrofil prepregs (product name “TR366E250S”, manufactured by Mitsubishi Rayon Co., Ltd.) were laminated so that the fiber axis directions of the reinforcing fibers were aligned, to obtain a laminate. The laminate was press molded with the mold 100 illustrated in FIG. 1 under conditions of a surface pressure of 8 MPa, a mold temperature of 140 ° C., and a molding time of 5 minutes to obtain a fiber-reinforced plastic molded body (molded plate).

[Examples 2 to 5]
Except having changed the composition and resin content of each component as shown in Table 1, thermosetting resin compositions (C-2) to (C-5) were prepared in the same manner as in Example 1, and resin films Was made. Using this resin film, a fiber-reinforced plastic molded body was obtained in the same manner as in Example 1.

[Comparative Example 1]
A thermosetting resin composition (X-1) was prepared in the same manner as in Example 1 except that the thermoplastic resin particles (c1-1) were not used. A resin film was produced in the same manner as in Example 1 except that the thermosetting resin composition (X-1) was used, and a fiber-reinforced plastic molded article was obtained in the same manner as in Example 1 using the resin film. It was.

[Comparative Example 2]
95 parts by mass of thermosetting resin (c2-1), 12.5 parts by mass of thermosetting resin (c2-2), and 7.7 parts by mass of thermoplastic resin (y-1) are charged into a melting pot. The mixture was heated to 80 ° C. and mixed, and then cooled to about 60 ° C. Furthermore, 5 parts by mass of the curing agent (e-1), 10 parts by mass of the curing agent (e-2), and 5 parts by mass of the curing agent (e-3) are added and stirred and mixed at 60 ° C. A composition (X-2) was obtained. A resin film was produced in the same manner as in Example 1 except that the thermosetting resin composition (X-2) was used, and a fiber-reinforced plastic molded article was obtained in the same manner as in Example 1 using the resin film. It was.

[Comparative Examples 3 to 5]
As shown in Table 1, heat was applied in the same manner as in Example 1 except that other thermoplastic resin particles (x-1) to (x-3) were used instead of the thermoplastic resin particles (c1-1). Curable resin compositions (X-3) to (X-5) were prepared. A resin film was produced in the same manner as in Example 1 except that the thermosetting resin compositions (X-3) to (X-5) were used, and fibers were produced in the same manner as in Example 1 using the resin film. A reinforced plastic molding was obtained.

Table 1 shows the results of measuring the viscosity at 30 ° C. and the minimum viscosity of the thermosetting resin compositions (C-1) to (C-5) and (X-1) to (X-5) in each example. . In addition, Table 1 shows the measurement results and evaluation results of the resin flow rate and the evaluation results of the coating appearance in each example.
In addition, the column of the temperature of the minimum viscosity in Table 1 means the temperature of the resin composition when the minimum viscosity is measured.

As shown in Table 1, in Examples 1 to 5 using resin films formed of thermosetting resin compositions (C-1) to (C-5) containing thermoplastic resin particles (c1), Excessive flow of the thermosetting resin compositions (C-1) to (C-5) at the time of molding was suppressed, and the coating appearance was also excellent.
Comparative Example 1 in which the thermoplastic resin particles (c1) are not used for the resin film, Comparative Example 2 in which the thermoplastic resin (y-1) that is not particulate is used instead of the thermoplastic resin particles (c1), and the thermoplastic resin particles In Comparative Example 3 using other thermoplastic resin particles (x-1) instead of (c1), excessive flow of the thermosetting resin composition was not sufficiently suppressed, and the coating appearance was poor.
In Comparative Examples 4 and 5 using the thermoplastic resin particles (x-2) and (x-3) instead of the thermoplastic resin particles (c1), the coating appearance was inferior.

DESCRIPTION OF SYMBOLS 1 Laminated body 2 Fiber reinforced plastic molding 3 Flat plate part 4 Side part 10 Prepreg base material 12 Prepreg laminated body 14 Resin film 20 Composite material part 22 Resin layer 100 Mold 110 Lower mold 112 Protrusion part 120 Upper mold 122 Concave part

Claims (11)

The manufacturing method of the fiber reinforced plastic molding which has a following lamination process and a formation process.
Lamination process: The following thermoplastic resin particles (on the surface of at least one of the prepreg laminates obtained by laminating a plurality of sheet-like prepreg substrates in which the reinforcing fiber substrate (A) is impregnated with the thermosetting resin composition (B) c1) contains a thermosetting resin composition containing the (C) fiber basis weight of 50 g / ^{m 2} or less reinforcing fiber base and (D) a resin film resin content of 50 to 500 g / ^{m 2} A step of stacking layers to obtain a laminate.
Molding step: a step of heating and pressurizing the laminate with a mold to obtain a fiber-reinforced plastic molded body.
Thermoplastic resin particles (c1): particles containing at least one thermoplastic resin selected from the group consisting of polyethersulfone, polyphenylene sulfide, polyetheretherketone, polyimide and polyetherimide. Average particle diameter of 0.1 to 100 [mu] m, method for producing a fiber-reinforced plastic molded article according to claim 1 of the thermoplastic resin particles (c1). The manufacturing method of the fiber reinforced plastic molding of Claim 1 or 2 whose said reinforced fiber base material (D) is a nonwoven fabric which consists of a reinforced fiber. The method for producing a fiber-reinforced plastic molded body according to any one of claims 1 to 3 , wherein a glass transition temperature of the thermoplastic resin particles (c1) is equal to or higher than a mold temperature in the molding step. The method for producing a fiber-reinforced plastic molded body according to any one of claims 1 to 4 , wherein the thermoplastic resin particles (c1) are polyethersulfone particles. The manufacturing method of the fiber reinforced plastic molding as described in any one of Claims 1-5 in which the said thermosetting resin composition (C) contains an epoxy resin. The manufacturing method of the fiber reinforced plastic molding as described in any one of Claims 1-6 in which the said thermosetting resin composition (B) contains an epoxy resin. Prior to the molding step, further comprising a shaping step of shaping the laminate obtained in the lamination step to obtain a preform,
The method for producing a fiber-reinforced plastic molded body according to any one of claims 1 to 7 , wherein the preform is used as the laminated body in the molding step.   9. The molding process according to claim 1, wherein in the molding step, the mold temperature during molding is 100 to 180 ° C., the surface pressure during molding is 1 to 15 MPa, and the molding time is 1 to 15 minutes. Method for producing a fiber-reinforced plastic molded article. The following thermoplastic resin particles (c1) are applied to at least one surface of a prepreg laminate in which a plurality of sheet-like prepreg substrates impregnated with the thermosetting resin composition (B) are reinforced on the reinforcing fiber substrate (A). the thermosetting resin composition containing (C) and fiber basis weight and containing a 50 g / ^{m 2} or less reinforcing fiber base (D), the resin film is further laminated resin content of 50 to 500 g / ^{m 2} Laminated body.
Thermoplastic resin particles (c1): particles containing at least one thermoplastic resin selected from the group consisting of polyethersulfone, polyphenylene sulfide, polyetheretherketone, polyimide and polyetherimide.   A fiber-reinforced plastic molded article formed by heating and pressurizing the laminate according to claim 10.

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