JP2006052385A - Epoxy resin composition for fiber-reinforced composite material, prepreg and fiber-reinforced composite material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a prepreg excellent in handleability and moldability and a resin composition which is suitable for providing the prepreg. <P>SOLUTION: The epoxy resin composition for fiber-reinforced composite materials comprises (A) an epoxy resin having a glass transition temperature or melting point not higher than room temperature, (B) an epoxy resin having ≥50°C glass transition temperature or melting point and having ≥1,000 molecular weight and dispersed as particulates in the resin composition and (C) a curing agent. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an epoxy resin composition, a prepreg, and a fiber reinforced composite material that are suitably used as a matrix resin for a fiber reinforced composite material.

  In recent years, fiber reinforced composite materials using carbon fibers, aramid fibers, etc. as reinforcing fibers have utilized their high specific strength and specific modulus to make structural materials such as aircraft and automobiles, tennis rackets, golf shafts, fishing rods, etc. It is used for general industrial purposes. Various methods are used for the production of fiber reinforced composite materials, and there is a method using a prepreg which is a sheet-like intermediate base material in which reinforcing fibers arranged in a sheet form are impregnated with an uncured matrix resin. Widely used. In this method, a composite material molding is usually obtained by laminating several prepregs, followed by heating and pressing.

  When a fiber reinforced composite material is obtained by a molding method using a sheet-like prepreg, the room temperature viscosity of the resin composition used for the fiber reinforced composite material is preferably low to some extent from the viewpoint of handleability of the prepreg. However, when an appropriate viscosity is given at room temperature, the viscosity during the curing process becomes too low, so that the resin flow increases and voids tend to occur.

  As a method of giving an appropriate viscosity at room temperature and during the curing process, for example, as disclosed in Patent Document 1 below, it is known that fine particles of an amorphous thermoplastic resin composition are dispersed in a thermosetting resin. The thermoplastic resin having high solubility with respect to the thermosetting resin is limited, and if the thermosetting / thermoplastic resin compatibility is not very good in the curing process, the thermosetting / thermoplastic resin The adhesiveness at the interface is weak, and the solvent resistance may be reduced.

Japanese Unexamined Patent Publication No. 7-76658

  The present invention relates to an epoxy resin composition, a prepreg, and a fiber reinforced composite material that are suitably used as a matrix resin for a fiber reinforced composite material.

In order to achieve the above object, the epoxy resin composition for fiber-reinforced composite material of the present invention includes the following [A], [B], and [C] components, and the [B] component is dispersed in the form of particles. It is the epoxy resin composition for fiber reinforced composite materials formed.
[A]: Epoxy resin having a glass transition temperature or melting point of room temperature or less
[B]: Epoxy resin having a glass transition temperature or melting point of 50 ° C. or higher and a molecular weight of 1000 or higher
[C]: Curing agent The method for producing an epoxy resin composition for fiber-reinforced composite material according to the present invention kneads the [B] component into the [A] component at a temperature 20 ° C. or more lower than the melting point of the [B] component. It has a process to do.

  The prepreg of the present invention comprises the epoxy resin composition and reinforcing fibers. Moreover, the fiber-reinforced composite material of the present invention includes the cured resin of the epoxy resin composition and reinforcing fibers.

  The manufacturing method of the prepreg of this invention impregnates the said epoxy resin composition in a reinforced fiber.

  According to the present invention, by dispersing the solid epoxy resin in the resin composition in the form of particles, the room temperature viscosity can be suppressed to a low viscosity, and a prepreg having both excellent handling properties and mechanical properties is obtained. be able to.

  Hereinafter, the present invention will be described in detail.

  The essential point of the present invention is that by dispersing the solid epoxy resin in the resin composition in the form of particles, the viscosity at room temperature can be suppressed to a low viscosity, and the epoxy resin composition having excellent handling properties and It is in the point which found out.

  The epoxy resin composition for fiber-reinforced composite materials of the present invention comprises the following [A] component as an essential component. Here, the component [A] is an epoxy resin having a glass transition temperature or a melting point of room temperature or lower.

  By blending the [A] component, appropriate tack and drape can be imparted to the prepreg at room temperature. The glass transition temperature here is a midpoint temperature obtained based on JIS K7121 using a differential calorimeter (DSC).

  Examples of such an epoxy resin include a glycidyl ether type epoxy resin obtained from a compound having a hydroxyl group in the molecule, a glycidyl amine type epoxy resin obtained from a compound having an amino group in the molecule, and a carboxyl group in the molecule. A glycidyl ester type epoxy resin obtained from a compound, a cycloaliphatic epoxy resin obtained from a compound having an unsaturated bond in the molecule, or an epoxy resin in which two or more types selected from these are mixed in the molecule are used. be able to.

  Commercially available products of bisphenol A type epoxy resin include Epicoat (registered trademark) 825, Epicoat 826, Epicoat 827, Epicoat 828, Epicoat 834 (above made by Japan Epoxy Resin Co., Ltd.), Epicron (registered trademark) 850 (Dainippon Ink Co., Ltd.) ), Epototo (registered trademark) YD-128 (manufactured by Toto Kasei Co., Ltd.), DER-331, DER-332 (manufactured by Dow Chemical Company), and the like.

  Commercially available products of bisphenol F type epoxy resin include Epicoat 806, Epicoat 807, Epicoat 1750 (above made by Japan Epoxy Resin Co., Ltd.), Epicron 830 (produced by Dainippon Ink and Chemicals), Epototo YD-170, Epototo YD-175 (above East Tokyo) Kasei Co., Ltd.).

  Examples of commercially available resorcinol-type epoxy resins include Denacol (registered trademark) EX-201 (manufactured by Nagase ChemteX).

  Specific examples of the glycidylamine type epoxy resin include tetraglycidyldiaminodiphenylmethanes, glycidyl compounds of aminophenol, glycidylanilines, and glycidyl compounds of xylenediamine.

  Commercially available products of tetraglycidyldiaminodiphenylmethanes include ELM434 (manufactured by Sumitomo Chemical Co., Ltd.), Araldite (registered trademark) MY720, Araldite MY721, Araldite MY722, Araldite MY9512, Araldite MY9612, Araldite MY9634, Araldite MYco63 YH-434 (manufactured by Toto Kasei Co., Ltd.), Epicoat 604 (manufactured by Japan Epoxy Resin Co., Ltd.) and the like can be mentioned.

  Examples of commercially available products of aminophenol glycidyl compounds include ELM120, ELM100 (manufactured by Sumitomo Chemical Co., Ltd.), Epicoat 630 (manufactured by Japan Epoxy Resin Co., Ltd.), Araldite MY0500, Araldite MY0510 (manufactured by Vantico).

  Examples of commercially available glycidylanilines include GAN and GOT (manufactured by Nippon Kayaku Co., Ltd.).

  Examples of the glycidyl compound of xylenediamine include TETRAD-X (manufactured by Mitsubishi Gas Chemical Company).

  Specific examples of the glycidyl ester type epoxy resin include phthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, isophthalic acid diglycidyl ester, dimer acid diglycidyl ester, and their halogen or alkyl-substituted products.

  Examples of commercially available products of diglycidyl phthalate include Epomic (registered trademark) R508 (manufactured by Mitsui Chemicals) and Denacol EX-721 (manufactured by Nagase ChemteX).

  Commercial products of hexahydrophthalic acid diglycidyl ester include Epomic R540 (manufactured by Mitsui Chemicals) and AK-601 (Nippon Kayaku).

  Examples of commercially available dimer acid diglycidyl ester include Epicoat 871 (manufactured by Japan Epoxy Range Co., Ltd.) and Epototo YD-171 (manufactured by Toto Kasei Co., Ltd.).

  Examples of commercially available alicyclic epoxy resins include Celoxide (registered trademark) 2021, Celoxide 2080 (manufactured by Daicel Chemical Industries, Ltd.), and CY179 (manufactured by Vantico).

  These [A] component epoxy resins may be used singly or in combination. Moreover, 40-85 weight% is desirable in [A] component in 100 weight% of all the epoxy resin compositions, More desirably, it is 50-75 weight%. If it is 40 parts by weight or less, the viscosity may be too high and the tack and drape properties may be insufficient. If it is 85 parts by weight or more, the viscosity may be too low and the tack may be excessive.

  The epoxy resin composition for fiber-reinforced composite materials of the present invention contains the following [B] component as an essential component. Here, the component [B] is an epoxy resin having a glass transition temperature or melting point of 50 ° C. or higher and a molecular weight of 1000 or higher.

  When the [B] component is dispersed in the resin composition in the form of particles, the viscosity of the composition can be suppressed near room temperature, and a resin composition excellent in handleability can be obtained. In the case of a solid epoxy resin having a glass transition temperature or melting point of less than 50 ° C. or a molecular weight of less than 1000, it may gradually dissolve in the epoxy resin composition during storage at room temperature, etc. There is a fear. In addition, the preferable range of the glass transition temperature or melting | fusing point of a [B] component is 50-160 degreeC, More preferably, it is 55-150 degreeC.

  Examples of such epoxy resins include bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, phenoxy-type epoxy resins, polyethylene glycol-type epoxy resins, polypropylene glycol-type epoxy resins, and halogen or alkyl-substituted products thereof. Of these, bisphenol A type epoxy resins and bisphenol F type epoxy resins, which can provide high interfacial adhesion, are preferably exemplified.

  Specific examples of commercially available bisphenol A type epoxy resins having a glass transition temperature or melting point of 50 ° C. or higher and a molecular weight of 1000 or higher include Epicoat 1002, Epicoat 1003, Epicoat 1004, Epicoat 1004AF, Epicoat 1007, Epicoat 1009 (above Japan) Epoxy resin).

  Specific examples of commercially available bisphenol F-type epoxy resins having a glass transition temperature or melting point of 50 ° C. or higher and a molecular weight of 1000 or more include Epicoat 4004P, Epicoat 4007P, Epicoat 4009P (manufactured by Japan Epoxy Resin Co., Ltd.), Epototo YDF2004 ( Toto Kasei Co., Ltd.).

  Specific examples of commercially available phenoxy epoxy resins having a glass transition temperature or melting point of 50 ° C. or higher and a molecular weight of 1000 or higher include Epicoat 1256 (manufactured by Japan Epoxy Resin Co., Ltd.).

  A curing agent may be included in the epoxy resin of the component [B]. Examples of the curing agent to be contained include aromatic amines and dicyandiamide. By containing these curing agents and curing accelerators, both toughness and heat resistance can be achieved.

  The blending amount of the component [B] is preferably 5 to 100 parts by weight, more preferably 30 to 80 parts by weight with respect to 100 parts by weight of the component [A], from the viewpoint of controlling the viscosity in the room temperature region and the high temperature region. More preferably, it is 35 to 75 parts by weight.

  In the epoxy resin composition of the present invention, the component [B] needs to be dispersed in the form of particles. Here, the particulate shape is not particularly limited.

  Moreover, it is preferable that the particle size of [B] component is 1-50 micrometers. More preferably, it is 1-15 micrometers. More preferably, it is 1-10 micrometers. If it is smaller than 1 μm, it may be easily dissolved in the component [A], and if it is 50 μm or more, it may cause a defect when forming a film, which is not preferable.

In addition, when the ratio V ₅₀ / V ₁₀₀ of the viscosity at 50 ° C. and the viscosity at 100 ° C. of the epoxy resin composition of the present invention is 1 or more and 100 or less, the epoxy resin composition has excellent handleability when used as a prepreg. Resin flow and void generation during the molding process can be suppressed.

  Moreover, the viscosity at 50 ° C. of the epoxy resin composition of the present invention is preferably 150 Pa · s or more and 2000 Pa · s or less. On the other hand, the viscosity at 100 ° C. is preferably 2 Pa · s or more and 200 Pa · s or less from the viewpoint of moldability. In this case, when the [A] component having a viscosity of 100 to 1500 Pa · s at 50 ° C. is selected, a resin composition having a preferable viscosity range can be obtained in combination with the above [B] component. Moreover, when the [C] component mentioned later is a liquid, by adjusting so that the viscosity in 50 degreeC of the mixture of a [A] component and a [C] component may be 200-1500 Pa.s, it is as an epoxy resin composition. A product having a preferred viscosity is obtained.

The viscosity at 50 ° C. and 100 ° C. here is determined by the following method. That is, using a dynamic viscoelasticity measuring apparatus (for example, rheometer RDA2: manufactured by Rheometrics, Inc.), using a parallel plate, the temperature is simply raised at a rate of temperature rise of 2 ° C./min, strain is 100%, frequency is 0.5 Hz , a plate spacing 1 mm, was measured from 50 ° C. to 100 ° C., in which the value of eta ^* at 50 ° C. and _{V 50,} the value of eta ^* at 100 ° C. and _{V 100.}

  The epoxy resin composition for fiber-reinforced composite materials of the present invention contains the following [C] component as an essential component. Here, the component [C] is a curing agent.

  Although it does not specifically limit as such a hardening | curing agent, An amine hardening | curing agent, an acid anhydride, the complex of boron trifluoride, etc. are mentioned. Of these, amine curing agents are preferred from the viewpoint of mechanical properties such as heat resistance.

  Examples of such amine curing agents include aromatic amines, dicyandiamide, and dibasic acid dihydrazide. Examples of aromatic amines include metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, and metaxylenediamine.

  These curing agents can be used alone or in combination of two or more. From the viewpoint of imparting heat resistance to the epoxy composition, diaminodiphenylmethane and diaminodiphenylsulfone are desirable.

  In the epoxy resin composition of the present invention, if necessary, in addition to the above-mentioned components [A] to [C], organic particles such as rubber particles and thermoplastic resin particles, and liquid thermosetting resins other than epoxy resins , A curing accelerator, a flame retardant, a silane coupling agent, and one or more soluble thermoplastic resins may be contained.

  As the rubber particles, cross-linked rubber particles and core-shell rubber particles obtained by graft polymerization of a different polymer on the surface of the cross-linked rubber particles are preferably used from the viewpoint of handleability and the like.

  Commercially available crosslinked rubber particles include FX-602P (model number, manufactured by Nippon Synthetic Rubber Industry Co., Ltd.) consisting of a crosslinked product of carboxyl-modified butadiene-acrylonitrile copolymer, and CX-MN series (model number, Japan) consisting of acrylic rubber fine particles. Catalyst), YR-500 series (model number, manufactured by Tohto Kasei) and the like can be used.

  Examples of commercially available core-shell rubber particles include, for example, Paraloid (registered trademark) EXL-2655 (manufactured by Kureha Chemical Industries) made of a butadiene / alkyl methacrylate / styrene copolymer, and an acrylate / methacrylate copolymer. Staphyloid (registered trademark) AC-3355, TR-2122 (manufactured by Takeda Pharmaceutical Co., Ltd.), PARALOID (registered trademark) EXL-2611, EXL-3387 (manufactured by Rohm & Haas, Inc.) made of butyl acrylate / methyl methacrylate copolymer ) Etc. can be used.

  As the thermoplastic resin particles, polyamide particles or polyimide particles are preferably used, and as commercially available polyamide particles, SP-500 (model number, manufactured by Toray Industries, Inc.), orgasol (registered trademark, manufactured by ATOCHEM), etc. may be used. it can.

  Examples of liquid thermosetting resins other than epoxy resins include cyanate ester resins, bismaleimide resins, and benzoxazine resins.

  As the soluble thermoplastic resin, polyethersulfone, polysulfone, polyimide, polyetherimide, polycarbonate, polyetherethersulfone, polyvinyl formal, polymethyl methacrylate and the like are preferably used.

  Next, an example of the manufacturing method of the epoxy resin composition for fiber reinforced composite materials of this invention is demonstrated. In the production method of the present invention, the [A], [B] and [C] components are mixed. Here, the temperature at the time of mixing component [B] should just be 20 degreeC or more lower than melting | fusing point of [B] component. More preferably, it should be 25 ° C. or lower. If the difference between the temperature during mixing and the melting point of the component [B] is less than 20 ° C., the component [B] may be dissolved in the component [A] by shearing heat during mixing. It becomes difficult to disperse into. The order of blending the [C] component and the [B] component is not particularly limited, and the [B] component and the [C] component may be blended substantially simultaneously. It is preferable to blend the component [C] after being dispersed in the component. When there exists a component mix | blended after a [B] component, it is desirable to mix | blend at 20 degreeC or more lower than melting | fusing point of a [B] component.

  Examples of the reinforcing fiber used in the prepreg of the present invention include glass fiber, Kevlar fiber, carbon fiber, graphite fiber, and boron fiber. Among these, carbon fiber is preferable in terms of specific strength and specific modulus.

The prepreg of the present invention preferably has a reinforcing fiber amount per unit area of 100 to 2000 g / m ² . When the amount of the reinforcing fiber is less than 100 g / m ^2, it is necessary to increase the number of laminated sheets in order to obtain a predetermined thickness, and the operation becomes complicated, which is not preferable. If it exceeds 2000 g / m ² , the drapability of the prepreg deteriorates, which is not preferable.

  The prepreg of the present invention preferably has a fiber weight content of 30 to 80%. Preferably it is 35 to 70%, more preferably 40 to 65%. If the fiber weight ratio is less than 30%, the amount of the resin is too large, and the advantages of the fiber reinforced composite material having excellent specific strength and specific elastic modulus cannot be obtained. Composite materials can be void-rich.

  The prepreg of the present invention is impregnated by applying the epoxy resin composition of the present invention onto a release paper with a reverse roll coater, knife coater, etc. to form a film, and superposing the reinforcing fiber and the epoxy resin composition film on each other and applying heat and pressure. Can be manufactured.

  When the epoxy resin composition of the present invention is applied to a release paper to form a film, the film may be formed at a temperature 20 ° C. or more lower than the melting point of the [B] component in order to prevent melting of the [B] component. is necessary. Further, when impregnating the reinforcing resin with the epoxy resin composition of the present invention, it is desirable to carry out at a temperature 20 ° C. or more lower than the melting point of the component [B]. This is not restrictive, and it is possible to impregnate at a temperature higher than the melting point if necessary.

  The fiber reinforced composite material of the present invention can be produced by shaping the above prepreg and heat curing. For shaping, one or more prepregs may be laminated on a mold, or one or more prepregs may be wound around a mandrel. Heating is performed by an apparatus such as an autoclave, an oven, or a press.

  The conditions for heat curing are selected such that the [B] component melts before the epoxy resin composition is gelled. Further, when the temperature is raised from room temperature to the curing temperature, the temperature may be increased to a curing temperature at a constant rate, or may be maintained at a certain temperature for a certain period of time, and then increased to the curing temperature. Thus, it is preferable from the point of the viscosity of an epoxy resin composition that the temperature in the case of hold | maintaining for a fixed time at the temperature in the middle is more than melting | fusing point of [B] component. Although it depends on the curing agent as the curing temperature, 120 to 220 ° C. is preferably used from the viewpoint of heat resistance after curing.

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

  In this example, the glass transition temperature of the uncured resin was measured using a differential calorimeter (DSC) and the midpoint temperature obtained based on JIS K7121 was used as the glass transition temperature. As the melting point of the crystalline thermosetting resin, the temperature of the melting peak obtained based on JIS K7121 was used.

  Moreover, the viscosity of the uncured product of the epoxy resin composition is simply increased by using a dynamic viscoelasticity measuring device (Rheometer RDA2: manufactured by Rheometrics) using a parallel plate at a temperature increase rate of 2 ° C./min. The measurement was performed at a strain of 100%, a frequency of 0.5 Hz, and a plate interval of 1 mm.

In this example, the prepreg was produced as follows. The epoxy resin composition was coated on release paper to prepare a resin film of 53.4 g / m ² basis weight. Carbon fiber “Torayca (registered trademark)” T700G-12K (12,000 fibers, tensile strength 4.9 GPa, tensile modulus 240 GPa, tensile elongation 2.1%) (Toray Industries, Inc.) (Made by Co., Ltd.) was laminated from both sides and impregnated with the resin composition while being heated and pressed to prepare a prepreg (fiber basis weight 190 g / m ² , resin content 36% by weight).

Example 1
ELM434 (glass transition temperature: −10 ° C., semi-solid) 50 parts by weight as component [A], Epicoat 630 (liquid) 35 parts by weight, and Epicoat 1256 (melting point: 85 ° C., molecular weight 50000) 15 parts as component [B] In addition, 47 parts by weight of 4,4′-DDS was used as the [C] component. Further, as other components, 20 parts by weight of Sumika Excel 5003P (polyethersulfone) was used.

In addition, about [B] component, it was set as the particle size of 2-10 micrometers by grind | pulverizing and classifying. The components [A] were heated and dissolved at 150 ° C. and then cooled to 60 ° C. at room temperature, and the components [B] and [C] were added and kneaded. The resin composition had a viscosity of 640 Pa · s at 50 ° C., a viscosity at 100 ° C. of 10 Pa · s, and V ₅₀ / V ₁₀₀ = 64.
When a prepreg was produced using this resin composition, both tack and drape were good.

(Example 2)
50 parts by weight of ELM434 as component [A], 25 parts by weight of Epicoat 825 (liquid), 25 parts by weight of Epicoat 1007 (melting point 128 ° C., molecular weight 4000) as component [B], 4,4′-DDS as component [C] Was used in an amount of 35 parts by weight. In addition, 7 parts by weight of Sumika Excel 5003P (polyethersulfone) was used as the other component.

In addition, about [B] component, it was set as the particle size of 2-10 micrometers by grind | pulverizing and classifying. The components [A] were heated and dissolved at 150 ° C. and then cooled to 60 ° C. at room temperature, and the components [B] and [C] were added and kneaded. The resin composition had a viscosity of 400 Pa · s at 50 ° C., a viscosity at 100 ° C. of 5 Pa · s, and V ₅₀ / V ₁₀₀ = 80.
When a prepreg was produced using this resin composition, both tack and drape were good.

(Example 3)
50 parts by weight of ELM 434 as component [A], 30 parts by weight of Epicoat 825, 20 parts by weight of Epicoat 1004AF (melting point 97 ° C., molecular weight 2000) as component [B], 38 of 4,4′-DDS as component [C] Part by weight was used. Further, 10 parts by weight of SUMIKAEXCEL 5003P (polyethersulfone) was used as the other component.

In addition, about [B] component, it was set as the particle size of 2-10 micrometers by grind | pulverizing and classifying. The components [A] were heated and dissolved at 150 ° C. and then cooled to 60 ° C. at room temperature, and the components [B] and [C] were added and kneaded. The resin composition had a viscosity of 250 Pa · s at 50 ° C., a viscosity at 100 ° C. of 4.5 Pa · s, and V ₅₀ / V ₁₀₀ = 55.6.
When a prepreg was produced using this resin composition, both tack and drape were good.

Example 4
100 parts by weight of Epicoat 1007 and 1 part by weight of dicyandiamide were kneaded using an extruder, followed by pulverization and classification to obtain epoxy particles having a particle size of 2 to 10 μm, which were used as component [B].
As the [A] component, 30 parts by weight of Epicoat 630, 40 parts by weight of Epicoat 825, 30 parts by weight of the above [B] component, and 34 parts by weight of 4,4′-DDS as the [C] component were used. In addition, 10 parts by weight of Sumika Excel 5003P (polyethersulfone) was used as the other component.

To component [A], the other components were heated and dissolved at 150 ° C., cooled to 60 ° C. at room temperature, added with component [B] and added with component [C] and kneaded. The resin composition had a viscosity of 310 Pa · s at 50 ° C., a viscosity at 100 ° C. of 4.1 Pa · s, and V ₅₀ / V ₁₀₀ = 75.6.
When a prepreg was produced using this resin composition, both tack and drape were good.

(Comparative Example 1)
As the component [A], 50 parts by weight of ELM434, 25 parts by weight of Epicoat 825, 25 parts by weight of Epicoat 1007 as the component [B], and 35 parts by weight of 4,4′-DDS as the component [C] were used. In addition, 7 parts by weight of Sumika Excel 5003P (polyethersulfone) was used as the other component.

The [B] component and other components were heated and dissolved at 150 ° C. in the component [A], cooled to 60 ° C. at room temperature, and the component [C] was added and kneaded. The resin composition had a viscosity of 2000 Pa · s at 50 ° C., a viscosity at 100 ° C. of 5 Pa · s, and V ₅₀ / V ₁₀₀ = 400.

  When a prepreg was produced using this resin composition, there was almost no tack and drapeability was impaired.

  The fiber reinforced composite material using the epoxy resin composition of the present invention is widely used for various structural materials and general industrial applications.

Claims (8)

An epoxy resin composition for fiber-reinforced composite material comprising the following [A], [B], and [C] components, and the [B] component dispersed in a particulate form.
[A]: Epoxy resin having a glass transition temperature or melting point of room temperature or lower [B]: Epoxy resin having a glass transition temperature or melting point of 50 ° C. or higher and a molecular weight of 1000 or higher [C]: Curing agent 2. The epoxy resin composition for fiber-reinforced composite material according to claim 1, wherein the ratio V ₅₀ / V ₁₀₀ of the viscosity V _{50 at} 50 ° C. to the viscosity V _{100 at} 100 ° C. is 1 or more and 100 or less.   The epoxy resin composition for fiber-reinforced composite materials according to claim 1 or 2, wherein the component (B) includes a bisphenol A type epoxy resin or a bisphenol F type epoxy resin.   The epoxy resin composition for fiber-reinforced composite materials according to any one of claims 1 to 3, wherein a curing agent is contained in the epoxy resin as component [B].   It is a method of manufacturing the epoxy resin composition for fiber-reinforced composite materials according to any one of claims 1 to 4, wherein the component [B] is [A] at a temperature 20 ° C. or more lower than the melting point of the component [B]. A method for producing an epoxy resin composition for a fiber-reinforced composite material, comprising a step of kneading the components.   A prepreg comprising the epoxy resin composition according to claim 1 and reinforcing fibers.   A fiber-reinforced composite material comprising the cured resin of the epoxy resin composition according to claim 1 and reinforcing fibers.   A method for producing a prepreg comprising a step of impregnating a reinforcing fiber with the epoxy resin composition according to any one of claims 1 to 4.