A preform includes a plurality of reinforcement fiber layers connected to each other by binder resin, the binder resin containing spacer particles insoluble in the binder resin, the spacer particles accounting for a volume proportion of 10% to 80% in the binder resin present in interlaminar gaps between the reinforcement fiber layers.

In the case of producing a fiber-reinforced composite material having excellent impact resistance by using an automatic lay up device, to provide a prepreg that can be layed up without adhesion and deposition of a part of the reinforced fibers or matrix resin in the device.

A prepreg containing the following components [A] to [E], wherein 85% by mass or more of the component [E] is present in a range within 9% of the average thickness of the prepreg from each surface of the prepreg, a range within 7% of the average thickness of the prepreg from each surface of the prepreg is composed of a first resin composition containing the components [B] to [E], and the prepreg satisfies the following conditions (I) to (V): [A] a carbon fiber, [B] an epoxy resin having two or more glycidyl groups in one molecule, [C] an aromatic amine compound, [D] a thermoplastic resin having a polyarylether skeleton, [E] a particle wherein primary particles have a number average particle size of 5 to 50 m, the content ratio (% by mass) of a thermoplastic resin and a thermosetting resin of 95:5 to 70:30, and a size of a crack generated when the particle is immersed in methyl ethyl ketone and boiled and refluxed for 24 hours is 20 m or less and the number of the crack is 5 or less; Condition (I): the component [B] contains 80% by mass or more of an epoxy resin having a viscosity at 25 C. of 2.010.sup.4 mPa.Math.s or more, Condition (II): a molar ratio of the number of active hydrogens in the component [C] to the number of epoxy groups in the component [B] is 0.7 to 1.3, Condition (III): the prepreg contains 15 to 25% by mass of the component [D] with respect to 100% by mass of the component [B], Condition (IV): the prepreg contains 50 to 80% by mass of the component [E] with respect to 100% by mass of the component [B], Condition (V): a minimum value of loss tangent tan of the first resin composition in the temperature range of 12 to 25 C. is 1.0 or less.

Peel ply for surface preparation and a method of surface preparation prior to adhesive bonding. A resin-rich peel ply is applied onto a curable, resin-based composite substrate, followed by co-curing. After co-curing, the composite substrate is fully cured but the matrix resin in the peel ply remains partially cured. When the peel ply is removed, a roughened, bondable surface with chemically-active functional groups is revealed. The composite substrate with the chemically-active, bondable surface may be bonded to another composite substrate to form a covalently-bonded structure.

The invention relates to a particulate curing component for a thermosetting resin, the particulate curing component comprising particles of a solid resin, wherein a curative for the thermosetting resin is dispersed within the particles of solid resin. The invention also relates to methods of forming particulate curing components and compositions comprising particulate curing components.

A reinforced thermoplastic resin composition which has good moldability and can increase a rigidity, impact resistance, mechanical strength, heat resistance and flame retardancy of an obtained molded article, and a molded article having a high rigidity, impact resistance, mechanical strength, heat resistance, flame retardancy, and weld strength. The reinforced thermoplastic resin composition including 80% to 100% by mass of a polycarbonate resin (A); a resin main component (C) containing 0% to 20% by mass of a specific graft copolymer (G); a polyethylene terephthalate resin (B) obtained by solid phase polymerization of recycled and/or repelletized material; an inorganic filler (D); and a glycidyl ether unit-containing polymer (E) having a mass average molecular weight of 3,800 to 60,000 at a specific ratio.

The molded article includes a fiber-reinforced composite material and a film of a resin composition on a surface of the fiber-reinforced composite material prepared by curing the resin composition, wherein the resin composition includes components [A] to [C]: component [A]: an aliphatic epoxy resin, component [B]: a thiol compound, and component [C]: a quaternary phosphonium salt.

A thermosetting resin composition for a fiber-reinforced composite material includes a domain of a base resin [A]; and a domain of a curing agent [B] and/or a domain of a catalyst [C], the thermosetting resin composition having a specific gravity of 0.90 to 1.30, and a complex viscosity * determined by dynamic viscoelasticity measurement at 25 C. of 110.sup.7 Pa.Math.s or more.

Provided is a method for producing a fiber-reinforced composite material exhibiting high heat resistance and excellent appearance quality. It is a method for producing a fiber-reinforced composite material, which includes disposing a prepreg containing a reinforced fiber being impregnated with an epoxy resin composition in a mold, pressurizing and heating the prepreg at 0.2 to 2.5 MPa and 130 C. to 200 C. as primary curing, and then further heating the prepreg at 210 C. to 270 C. for 10 minutes or more as secondary curing.

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.

A resin composition for a fiber-reinforced composite material that makes it possible to improve productivity by suppressing deformation at the time of removal from a mold, in particular, in the PCM method, while achieving both rapid curing and storage stability. The resin composition for a fiber-reinforced composite material includes an epoxy resin (A) including a phenol novolac epoxy resin and a bisphenol A epoxy resin; a phenoxy resin (B); dicyandiamide (C); an imidazole-based curing aid (D); and a phenol-based curing accelerator (E) as essential components, wherein the phenol novolac epoxy resin of the epoxy resin (A) constitutes 40 parts by mass to 75 parts by mass, the bisphenol A epoxy resin constitutes 10 parts by mass to 35 parts by mass, and the phenoxy resin (B) constitutes 5 parts by mass to 15 parts by mass in the total of 100 parts by mass of the components (A) to (E).