Abstract: A fiber-reinforced composite material is provided which is capable of achieving CAI, ILSS, and interlaminar fracture toughness concurrently at high levels, in particular, capable of achieving high CAI. The composite material is composed of a laminated body including a plurality of reinforcing-fiber-containing layers and a resin layer in each interlaminar region between adjacent reinforcing-fiber-containing layers, wherein the resin layer is a layer wherein a cured product of a compound having in its molecule a benzoxazine ring of formula (1) and epoxy resin is impregnated with at least polyamide 12 powder: (R1: C1-C12 chain alkyl group or the like; H is bonded to at least one of the carbon atoms of the aromatic ring at ortho- or para-position with respect to C to which the oxygen atom is bonded).

Abstract: The purpose of the present invention is to inhibit a decrease in strength attribute to the interface between a simple-shape portion and a complicated-shape portion. This fiber-reinforced resin composite material comprises: a simple-shape portion formed from at least one sheet-shaped prepreg material obtained by impregnating reinforcing fibers with a resin; and a complicated-shape portion obtained by impregnating reinforcing fibers with a resin, the complicated-shape portion having been integrated with the simple-shape portion. The resin used for the preprg material comprised the same components as the resin used for the complicated-shape portion.

Abstract: A composite material includes laminated composite material sheets having conductivity, partitioning members provided between end parts of sets of the composite material sheets to mutually separate the sets of the composite material sheets, and metal sheets respectively provided in the separated end parts of the composite material sheets so as to be respectively pinched between the composite material sheets.

Abstract: A prepreg 10 comprises: a reinforcing fiber layer 3 including reinforcing fibers 1 and a resin composition 2 with which the space between fibers of the reinforcing fibers 1 is impregnated and which contains (A) a benzoxazine resin, (B) an epoxy resin, and (C) a curing agent having 2 or more phenolic hydroxy groups in a molecule; and a surface layer 6a or 6b provided on at least one surface of the reinforcing fiber layer 3 and containing (A) a benzoxazine resin, (B) an epoxy resin, (C) a curing agent having 2 or more phenolic hydroxy groups in a molecule, and (D) polyamide resin particles 4 having an average particle size of 5 to 50 ?m, wherein the polyamide resin particles 4 include a particle made of a polyamide 11.

Abstract: Composite material sheets containing conductive fibers are laminated, and release films are interposed between the sheets so as to extend from one end to the center of the sheets. The sheets are heated under pressure to shape a composite material. Discrete conductive wires through which a measurement current is passed are connected to end surfaces of the respective layers in the composite material on the side on which the release films are interposed. A common conductive wire through which the measurement current is passed is connected to a surface of one of an uppermost layer and a lowermost layer at an end of the composite material opposite to the side on which the release films are interposed. A current is passed between the common conductive wire and the discrete conductive wires. Currents in the respective layers are sequentially or simultaneously measured using an ammeter.

Abstract: A production method for a fiber-reinforced composite material comprises: a step of stacking a prepreg plurally to obtain a prepreg-stacked body; and a step of heating the prepreg-stacked body to cure a resin, wherein the prepreg comprises: a reinforcing fiber layer including reinforcing fibers and a resin composition with which the space between fibers of the reinforcing fibers is impregnated and which contains (A) a benzoxazine resin, (B) an epoxy resin, and (C) a curing agent having 2 or more phenolic hydroxy groups in a molecule; and a surface layer provided on at least one surface of the reinforcing fiber layer and containing (A) to (C) components, and (D) polyamide resin particles having an average particle size of 5 to 50 ?m.

Abstract: The prepreg comprises: a reinforcing fiber layer including reinforcing fibers and a resin composition with which the space between fibers of the reinforcing fibers is impregnated and which contains (A) a benzoxazine resin, (B) an epoxy resin, and (C) a curing agent having 2 or more phenolic hydroxy groups in a molecule; and a surface layer provided on a surface of the reinforcing fiber layer and containing (A) to (C) components, and (D) polyamide resin particles having an average particle size of 5 to 50 ?m, wherein the polyamide resin particles include polyamide resin particles made of copolymers in which caprolactam and laurolactam are copolymerized at a molar ratio of 1:9 to 3:7 and at a molar ratio of 9:1 to 7:3, respectively.

Abstract: The prepreg comprises: a reinforcing fiber layer including reinforcing fibers and a resin composition with which the space between fibers of the reinforcing fibers is impregnated and which contains (A) a benzoxazine resin, (B) an epoxy resin, and (C) a curing agent having 2 or more phenolic hydroxy groups in a molecule; and a surface layer provided on a surface of the reinforcing fiber layer and containing (A) a benzoxazine resin, (B) an epoxy resin, (C) a curing agent having 2 or more phenolic hydroxy groups in a molecule, and (D) polyamide resin particles having an average particle size of 5 to 50 ?m, wherein the polyamide resin particles include a polyamide 12 resin particle and a polyamide 1010 resin particle.

Abstract: The prepreg comprises: a reinforcing fiber layer including reinforcing fibers and a resin composition with which the space between fibers of the reinforcing fibers is impregnated and which contains (A) a benzoxazine resin, (B) an epoxy resin, and (C) a curing agent having 2 or more phenolic hydroxy groups in a molecule; and a surface layer provided on a surface of the reinforcing fiber layer and containing (A) a benzoxazine resin, (B) an epoxy resin, (C) a curing agent having 2 or more phenolic hydroxy groups in a molecule, and (D) polyamide resin particles having an average particle size of 5 to 50 ?m, wherein the polyamide resin particles include a polyamide resin particle made of a copolymer in which caprolactam and laurolactam are copolymerized at a molar ratio of 1:9 to 3:7 and a polyamide 1010 resin particle.

Abstract: The prepreg comprises: a reinforcing fiber layer including reinforcing fibers and a resin composition with which the space between fibers of the reinforcing fibers is impregnated and which contains (A) a benzoxazine resin, (B) an epoxy resin, and (C) a curing agent having 2 or more phenolic hydroxy groups in a molecule; and a surface layer provided on a surface of the reinforcing fiber layer and containing the (A) to (C) components, and (D) polyamide resin particles having an average particle size of 5 to 50 ?m, wherein the polyamide resin particles include a polyamide 12 resin particle and a polyamide resin particle made of a copolymer in which caprolactam and laurolactam are copolymerized at a molar ratio of 9:1 to 7:3.

Abstract: A composite material includes laminated composite material sheets having conductivity, partitioning members provided between end parts of sets of the composite material sheets to mutually separate the sets of the composite material sheets, and metal sheets respectively provided in the separated end parts of the composite material sheets so as to be respectively pinched between the composite material sheets.

Abstract: A prepreg 10 comprises: a reinforcing fiber layer 3 including reinforcing fibers 1 and a resin composition 2 with which the space between fibers of the reinforcing fibers 1 is impregnated and which contains (A) a benzoxazine resin, (B) an epoxy resin, and (C) a curing agent having 2 or more phenolic hydroxy groups in a molecule; and a surface layer 6a or 6b provided on at least one surface of the reinforcing fiber layer 3 and containing (A) a benzoxazine resin, (B) an epoxy resin, (C) a curing agent having 2 or more phenolic hydroxy groups in a molecule, and (D) polyamide resin particles 4 having an average particle size of 5 to 50 ?m, wherein the polyamide resin particles 4 include a particle made of a polyamide 11.

Abstract: A production method for a fiber-reinforced composite material comprises: a first step of stacking a prepreg including: a reinforcing fiber layer including reinforcing fibers and a resin composition with which the space between fibers of the reinforcing fibers is impregnated and a surface layer provided on at least one surface of the reinforcing fiber layer and containing polyamide resin particles having an average particle size of 5 to 50 ?m and a melting point of 175 to 210° C. plurally and performing heating at a temperature of 120° C. or more and less than M1° C. when the melting point of the polyamide resin particles measured in the composition forming the surface layer is denoted by M1° C.; and a second step of performing heating at a temperature of M1° C. or more after the first step to cure the resin.

Abstract: A prepreg 10 comprises: a reinforcing fiber layer 3 including reinforcing fibers 1 and a resin composition 2 with which the space between fibers of the reinforcing fibers is impregnated and which contains (A) a benzoxazine resin, (B) an epoxy resin, and (C) a curing agent represented by the following formula (C-1); and surface layers 6a and 6b provided on the surfaces of the reinforcing fiber layer 3 and containing (A) a benzoxazine resin, (B) an epoxy resin, (C) a curing agent represented by the following formula (C-1), and (D) polyamide resin particles 4 having an average particle size of 5 to 50 wherein the polyamide resin particles 4 include a polyamide 12 resin particle or a polyamide 1010 resin particle.

Abstract: A prepreg 10 comprises: a reinforcing fiber layer 3 including reinforcing fibers 1 and a resin composition 2 with which the space between fibers of the reinforcing fibers is impregnated and which contains (A) a benzoxazine resin, (B) an epoxy resin, and (C) a curing agent having 2 or more phenolic hydroxy groups in a molecule; and surface layers 6a and 6b provided on the surfaces of the reinforcing fiber layer 3 and containing (A) a benzoxazine resin, (B) an epoxy resin, (C) a curing agent having 2 or more phenolic hydroxy groups in a molecule, and (D) polyamide resin particles 4 having an average particle size of 5 to 50 ?m, wherein the polyamide resin particles 4 include the polyamide 1010 resin particle.

Abstract: A prepreg 10 comprises: a reinforcing fiber layer 3 including reinforcing fibers 1 and a resin composition 2 with which the space between fibers thereof is impregnated and which contains (A) a benzoxazine resin, (B) an epoxy resin, and (C) a curing agent having 2 or more phenolic hydroxy groups; and surface layers 6a and 6b provided on the surfaces of the reinforcing fiber layer 3 and containing (A) a benzoxazine resin, (B) an epoxy resin, (C) a curing agent having 2 or more phenolic hydroxy groups, and (D) polyamide resin particles 4 having an average particle size of 5 to 50 wherein the polyamide resin particles 4 include a particle made of a copolymer in which caprolactam and laurolactam are copolymerized at a molar ratio of 9:1 to 7:3 and having a melting point of 180° C. or more.

Abstract: A fiber-reinforced composite material is provided which is capable of achieving CAI, ILSS, and interlaminar fracture toughness concurrently at high levels, in particular, capable of achieving high CAI. The composite material is composed of a laminated body including a plurality of reinforcing-fiber-containing layers and a resin layer in each interlaminar region between adjacent reinforcing-fiber-containing layers, wherein the resin layer is a layer wherein a cured product of a compound having in its molecule a benzoxazine ring of formula (1) and epoxy resin is impregnated with at least polyamide 12 powder: (R1: C1-C12 chain alkyl group or the like; H is bonded to at least one of the carbon atoms of the aromatic ring at ortho- or para-position with respect to C to which the oxygen atom is bonded).

Abstract: Composite material sheets containing conductive fibers are laminated, and release films are interposed between the sheets so as to extend from one end to the center of the sheets. The sheets are heated under pressure to shape a composite material. Discrete conductive wires through which a measurement current is passed are connected to end surfaces of the respective layers in the composite material on the side on which the release films are interposed. A common conductive wire through which the measurement current is passed is connected to a surface of one of an uppermost layer and a lowermost layer at an end of the composite material opposite to the side on which the release films are interposed. A current is passed between the common conductive wire and the discrete conductive wires. Currents in the respective layers are sequentially or simultaneously measured using an ammeter.

Abstract: Fiber-reinforced composite material is provided which is capable of achieving high levels of CAI, ILSS, and interlaminar fracture toughness concurrently, in particular, capable of achieving high ILSS at high CAI, temperature, and humidity. The fiber-reinforced composite material is composed of a laminated body including a plurality of reinforcing-fiber-containing layers and a resin layer in each interlaminar region between adjacent reinforcing-fiber-containing layers, wherein the resin layer is a layer wherein at least polyethersulphone particles are impregnated with a cured product of epoxy resin and a compound having in its molecule a benzoxazine ring represented by formula (1): wherein R1 has the same meaning as defined in the specification. The composite material is useful in automobile-, railroad-vehicle-, aircraft-, and ship-related applications, building components, such as windmills, and other general industry-related applications.

Abstract: A fiber-reinforced composite material is provided which is capable of achieving CAI, ILSS, and interlaminar fracture toughness concurrently at high levels, in particular, capable of achieving high CAI. The composite material is composed of a laminated body including a plurality of reinforcing-fiber-containing layers and a resin layer in each interlaminar region between adjacent reinforcing-fiber-containing layers, wherein the resin layer is a layer wherein a cured product of a compound having in its molecule a benzoxazine ring of formula (1) and epoxy resin is impregnated with at least polyamide 12 powder: (R1: C1-C12 chain alkyl group or the like; H is bonded to at least one of the carbon atoms of the aromatic ring at ortho- or para-position with respect to C to which the oxygen atom is bonded).