Abstract: A thermosetting resin composition contains at least: [A] a thermosetting resin; [B] a curing agent; and [C] polyamide particles satisfying following (c1) to (c6): (c1) a melting point of polyamide resin constituting the polyamide particles is 200 to 300° C.; (c2) a crystallization temperature of the polyamide resin constituting the polyamide particles is 150° C. to 250° C.; (c3) a number average particle size of the polyamide particles is 1 to 100 ?m; (c4) a sphericity of the polyamide particles is 80 to 100; and (c5) the linseed oil absorption of the polyamide particles is 10 to 100 mL/100 g. A thermosetting resin composition of the present invention enables suitable production of a fiber-reinforced composite material having sufficient compressive strength after impact and wet heat compression performance.

Abstract: The present invention addresses the problem of providing a prepreg that yields a carbon fiber composite material that has exceptional tensile strength, heat resistance, and impact resistance and is suitable as a structural material of an aircraft body, wherein the resin composition used in the prepreg furthermore has exceptional viscosity stability, the prepreg containing a resin composition that contains carbon fibers and at least the constituent elements [A]—[D] as defined.

Abstract: A prepreg includes composition elements [A], [B], and [C] described below, [A] a reinforcing fiber, [B] a thermosetting resin, and [C] a thermoplastic resin. [C] is present on a surface of the prepreg, [B] contains a first curing agent [b1] and a second curing agent [b2], and the reinforcing fiber of [A] that crosses over a boundary surface between a resin region containing [B] and a resin region containing [C] and that is in contact with both resin regions is present.

Abstract: A prepreg containing the following constituent elements [A] to [C], wherein a resin composition containing the constituent elements [B] and [C] has a higher-order structure derived from a diffraction angle 2? between 1.0° and 6.0° observed with X-ray diffraction after curing: [A]: carbon fibers [B]: epoxy resin [C]: curing agent of [B].

Abstract: A prepreg, which includes a carbon fiber reinforced material, has excellent Mode I interlaminar toughness, Mode II interlaminar toughness, and tensile strength. The prepreg includes the following constituents [A] to [C] and satisfies the following conditions (I) and (II): [A]: a carbon fiber; [B]: an epoxy resin; and [C]: a hardener for [B], and (I) a surface oxygen concentration O/C of [A] measured by X-ray photoelectron spectroscopy is 0.10 or more; and (II) a cured product obtained by curing [B] and [C] includes a resin region having molecular anisotropy exhibiting interference fringes in polarizing microscope observation in a crossed Nicol state.

Abstract: The invention provides a prepreg having high storage stability and serving suitably for producing components, such as structural members and interior members of aircraft and structural members of aircraft engines, that require high heat resistance under high temperature and high humidity conditions, where the prepreg exhibits good physical properties and good combustion properties. The prepreg is produced by impregnating component [A] with an epoxy resin composition containing components [B] to [D], wherein component [A] in the prepreg accounts for 50 mass % or more, where [A] is a carbon fiber, [B] is an epoxy resin, [C] is a fluorene type curing agent having a maximum particle size of 100 ?m or less, and [D] is a thermoplastic resin.

Abstract: An object of the present invention is to provide an epoxy resin composition capable of providing a carbon fiber-reinforced composite material that is excellent in moldability, heat resistance, and mechanical properties such as tensile strength and compression strength, and a prepreg. The present invention provides an epoxy resin composition containing at least components [A] to [D] shown below: [A]: an epoxy resin having a xylene group; [B]: a glycidyl amine epoxy resin having three or more glycidyl groups in a molecule; [C]: a thermoplastic resin; and [D]: an aromatic polyamine, the epoxy resin composition containing 10 to 80 parts by mass of the component [A] and 20 to 90 parts by mass of the component [B] based on 100 parts by mass in total of epoxy resins, and also 1 to 25 parts by mass of the component [C] based on 100 parts by mass in total of epoxy resins.

Abstract: Provided is a prepreg including the following constituents [A] to [C], the prepreg satisfying the following conditions [I] to [III]: [A]: a sizing agent-coated carbon fiber; [B]: an epoxy resin having a specific structure; and [C]: a hardener for [B], [I]: an epoxy resin composition including the constituents [B] and [C] has a nematic-isotropic phase transition temperature in a temperature range of 130° C. to 180° C.; [II] a prepreg after isothermal holding at 100° C. for 30 minutes does not have a high-order structure originated from a diffraction angle of 2?=1.0° to 6.0° measured by wide angle X-ray diffraction at 100° C.; and [III]: a prepreg after isothermal holding at 180° C. for 2 hours has a high-order structure originated from the diffraction angle of 2?=1.0° to 6.0° measured by wide angle X-ray diffraction at 180° C.

Abstract: A prepreg includes following constituents [A] to [C] and satisfies following conditions (I) and (II): [A]: a carbon fiber; [B]: an epoxy resin; and [C]: a hardener for [B], and (I) a surface oxygen concentration O/C of [A] measured by X-ray photoelectron spectroscopy is 0.10 or more; and (II) a cured product obtained by curing [B] and [C] includes a resin region having molecular anisotropy exhibiting interference fringes in polarizing microscope observation in a crossed Nicol state.

Abstract: Provided are: an epoxy resin composition that gives a carbon fiber-reinforced composite material having excellent moldability, heat resistance, and mechanical properties such as tensile strength and compressive strength; and a prepreg. An epoxy resin composition containing at least the following constituent elements [A]-[D]. The epoxy resin composition contains 5-50 parts by mass of constituent element [A] and 20-95 parts by mass of constituent element [B], as well as 1-25 parts by mass of constituent element [C], relative to 100 parts by mass of the total amount of epoxy resin. Constituent element [A] is an epoxy resin having primarily two epoxy groups and one or more condensed polycyclic aromatic hydrocarbon skeletons within a repeating unit of a specific structure; [B] is a glycidylamine epoxy resin having three or more glycidyl groups in the molecule; [C] is a sulfone or imide thermoplastic resin; and [D] is an epoxy resin curing agent.

Abstract: A prepreg containing at least the following components [A]-[F], wherein the ratio Ne/Nd of the number of structures Ne of component [F] present in a range of outside 110% of the particle diameter of component [E] and the number of structures Nd of component [F] present in a range outside 110% of the particle diameter of component [D] is 0.25 or higher. [A]: Carbon fibers, [B] thermosetting resin, [C]: curing agent, [D]: particles composed mainly of thermoplastic resin having a primary particle number-average particle size of 5-50 ?m, [E]: conductive particles different from component [D] and having a primary particle number-average particle size in the range of a specific expression, [F]: filler comprising a carbon material.

Abstract: A prepreg containing the following constituent elements [A] to [C], wherein a resin composition containing the constituent elements [B] and [C] has a higher-order structure derived from a diffraction angle 20 between 1.0° and 6.0° observed with X-ray diffraction after curing: [A]: carbon fibers [B]: epoxy resin [C]: curing agent of [B].

Abstract: An object of the present invention is to provide an epoxy resin composition capable of providing a carbon fiber-reinforced composite material that is excellent in moldability, heat resistance, and mechanical properties such as tensile strength and compression strength, and a prepreg. The present invention provides an epoxy resin composition containing at least components [A] to [D] shown below: [A]: an epoxy resin having a xylene group; [B]: a glycidyl amine epoxy resin having three or more glycidyl groups in a molecule; [C]: a thermoplastic resin; and [D]: an aromatic polyamine, the epoxy resin composition containing 10 to 80 parts by mass of the component [A] and 20 to 90 parts by mass of the component [B] based on 100 parts by mass in total of epoxy resins, and also 1 to 25 parts by mass of the component [C] based on 100 parts by mass in total of epoxy resins.

Abstract: A epoxy resin composition includes a given epoxy resin [A], an aromatic amine compound [B], an organic acid hydrazide compound [C] having a structural formula represented by general formula (I) or (II) (X is a structure selected from among monocyclic and polycyclic aromatic ring structures, polycyclic aromatic ring structures, and aromatic heterocyclic structures and optionally has, as a substituent, any of C4 or lower alkyl groups, a hydroxy group, and an amino group), and a thermoplastic resin [D], wherein the amount of the constituent element [C] is 1-25 parts by mass per 100 parts by mass of the constituent element [A], the epoxy resin composition, after having been held at 80° C. for 2 hours, having a viscosity which is up to 2.0 times the initial viscosity at 80° C.

Abstract: Provided is an epoxy resin composition for giving a carbon fiber-reinforced composite material that simultaneously achieves tensile strength and compressive strength. An epoxy resin composition containing at least the following constituent elements [A]-[D] wherein the epoxy resin composition contains 5-50 mass % of constituent element [A] and 20-95 mass % of constituent element [B] relative to 100 mass % of total epoxy resin weight. [A]: at least one epoxy resin selected from 1,2-bis(glycidyloxy)benzene, 1,3-bis(glycidyloxy)benzene, 1,4-bis(glycidyloxy)benzene, derivatives of these, and epoxy resins having a structure represented by general formula [1] (in general formula [1], at least one of R1-R5 and at least one of R6-R10 is a glycidyl ether group, and the other R1-R10 represent any of a hydrogen atom, halogen atom, or aliphatic hydrocarbon group having four or fewer carbon atoms.

Abstract: Provided are: an epoxy resin composition that gives a carbon fiber-reinforced composite material having excellent moldability, heat resistance, and mechanical properties such as tensile strength and compressive strength; and a prepreg. An epoxy resin composition containing at least the following constituent elements [A]-[D]. The epoxy resin composition contains 5-50 parts by mass of constituent element [A] and 20-95 parts by mass of constituent element [B], as well as 1-25 parts by mass of constituent element [C], relative to 100 parts by mass of the total amount of epoxy resin. Constituent element [A] is an epoxy resin having primarily two epoxy groups and one or more condensed polycyclic aromatic hydrocarbon skeletons within a repeating unit of a specific structure; [B] is a glycidylamine epoxy resin having three or more glycidyl groups in the molecule; [C] is a sulfone or imide thermoplastic resin; and [D] is an epoxy resin curing agent.

Abstract: Provided is an epoxy resin composition including the following component [A]: a tri- or more functional binaphthalene epoxy resin represented by the following general formula (A-1) and component [B]: an aromatic amine compound, in which the glass transition temperature of a cured product, which is obtained by curing the epoxy resin composition at 180° C. for 2 hours, after immersing in boiling water at 1 atm for 48 hours is 180° C. or more. An epoxy resin composition and a prepreg which can form a fiber-reinforced composite material excellent in heat resistance under high humidity are provided.

Abstract: Embodiments herein relate to a prepreg comprising a thermosetting resin, and reinforcing fibers in the thermosetting resin, wherein when the prepreg is cured in vacuum bag only conditions, and a method of making the same. The method also applies for autoclave processing. Embodiments also relate to a cured fiber reinforced composite material made by thermally curing the prepreg.

Abstract: Provided is an epoxy resin composition for giving a carbon fiber-reinforced composite material that simultaneously achieves tensile strength and compressive strength. An epoxy resin composition containing at least the following constituent elements [A]-[D] wherein the epoxy resin composition contains 5-50 mass % of constituent element [A] and 20-95 mass % of constituent element [B] relative to 100 mass % of total epoxy resin weight. [A]: at least one epoxy resin selected from 1,2-bis(glycidyloxy)benzene, 1,3-bis(glycidyloxy)benzene, 1,4-bis(glycidyloxy)benzene, derivatives of these, and epoxy resins having a structure represented by general formula [1] (in general formula [1], at least one of R1-R5 and at least one of R6-R10 is a glycidyl ether group, and the other R1-R10 represent any of a hydrogen atom, halogen atom, or aliphatic hydrocarbon group having four or fewer carbon atoms.

Abstract: A epoxy resin composition includes a given epoxy resin [A], an aromatic amine compound [B], an organic acid hydrazide compound [C] having a structural formula represented by general formula (I) or (II) (X is a structure selected from among monocyclic and polycyclic aromatic ring structures, polycyclic aromatic ring structures, and aromatic heterocyclic structures and optionally has, as a substituent, any of C4 or lower alkyl groups, a hydroxy group, and an amino group), and a thermoplastic resin [D], wherein the amount of the constituent element [C] is 1-25 parts by mass per 100 parts by mass of the constituent element [A], the epoxy resin composition, after having been held at 80° C. for 2 hours, having a viscosity which is up to 2.0 times the initial viscosity at 80° C.