Abstract: A prepreg and an integrally molded article are described, the prepreg including a thermoplastic resin existing on one face of a layer in which reinforcing fibers are impregnated with a thermosetting resin, wherein the prepreg exhibits, in injection molding or press molding, thermal weldability with a member containing a thermoplastic resin, and wherein the thermosetting resin has a specific peak on a loss tangent (tan ?) curve obtained by dynamic mechanical analysis (DMA), so that the prepreg exhibits suitable flexibility and adhesiveness, excellent formability on a complicated mold face, and adhesion to a mold face, causes no positional shift, and can be efficiently reinforced and stiffened at an intended position.

Abstract: An object is to provide an incised prepreg having desired formability stably, wherein the incised prepreg contains unidirectionally oriented reinforcing fibers and matrix resin and has an incised region containing a plurality of incisions made to divide reinforcing fibers, wherein the incised region includes a plurality of incision rows, each containing a plurality of incisions having nearly equal fiber-directionally projected lengths and aligned at substantially constant intervals in the fiber direction and wherein the distance L1, measured at right angles to the fiber direction, between two incision rows located on either side of an arbitrarily selected incision row and the fiber-directionally projected length L2 of the latter incision row satisfy the following relation: ?1.0<L1/L2<0.5.

Abstract: A substantially flat-plate-shaped laminated base material has at least a layer-shaped body ? and a layer-shaped body ? are layered or disposed side by side, the layer-shaped body ? having one or more cut prepregs A in which reinforcing fibers oriented in one direction are impregnated with a resin composition, the volume fraction of fiber is 45-65%, and at least a portion of the reinforcing fibers are segmented into a fiber length of 10-300 mm by a plurality of cuts, and the layer-shaped body ? having one or more base materials B in which reinforcing fibers having a fiber length in the range of 10-300 mm are impregnated with a resin composition.

Abstract: An intermediate base material is provided that is excellent in the conformity to three-dimensional shapes and that, when formed into a fiber reinforced plastic, develops good surface quality and high mechanical properties. According to one aspect, an incised prepreg is provided that has, in at least a partial region in a prepreg that contains unidirectionally oriented reinforcing fibers and a resin, a plurality of incisions that divide reinforcing fibers, wherein, in the case where a population is made up of the numbers of incisions contained in ten small circular regions of 10 mm in diameter randomly selected in the aforementioned region, a mean value for the population is 10 or greater and a coefficient of variation therefor is within 20%.

Abstract: An intermediate base material is provided that is excellent in the conformity to three-dimensional shapes and that, when formed into a fiber reinforced plastic, develops good surface quality and high mechanical properties. According to one aspect, an incised prepreg is provided that has, in at least a partial region in a prepreg that contains unidirectionally oriented reinforcing fibers and a resin, a plurality of incisions that divide reinforcing fibers, wherein, in the case where a population is made up of the numbers of incisions contained in ten small circular regions of 10 mm in diameter randomly selected in the aforementioned region, a mean value for the population is 10 or greater and a coefficient of variation therefor is within 20%.

Abstract: A prepreg, including: a fiber layer containing unidirectionally arranged discontinuous carbon fibers and a thermosetting resin; and a resin layer existing on at least one side of said fiber layer and containing a thermosetting resin and a thermoplastic resin; in which said prepreg contains carbon fibers having an areal weight of fibers of 120 to 300 g/m2, and has a mass fraction of resin of 25 to 50% with respect to the whole mass of said prepreg; and in which a temperature at which a coefficient of interlayer friction is 0.05 or less is in a temperature range of from 40 to 80° C., the interlayer friction being caused at the contact interface between layers of said prepreg when the middle one of three layers that are each made of said prepreg and laid up is pulled out, said coefficient of interlayer friction being measured at 10° C. intervals in a temperature range of from 40 to 80° C. under conditions including a pulling speed of 0.2 mm/min, a perpendicular stress of 0.08 MPa, and a pulling length of 1 mm.

Abstract: A method of producing a fiber reinforced plastic includes a laminating step of laminating a plurality of groups of prepregs containing an incised prepreg to obtain a prepreg laminate, when the incised prepreg is formed by providing at least a partial region in a prepreg containing unidirectionally oriented reinforcing fibers and a resin with a plurality of incisions that divide the reinforcing fibers, a forming step of disposing the prepreg laminate on a top surface of a mold containing the top surface and a side surface or disposing the prepreg laminate on a bottom surface of a mold containing the bottom surface and a side surface, and bending and forming the prepreg laminate along the side surface to obtain a preform having an approximate shape of the mold, and a solidifying step of disposing and solidifying the preform in a mold different than the mold used in the forming step.

Abstract: A substantially flat-plate-shaped laminated base material has at least a layer-shaped body ? and a layer-shaped body ? are layered or disposed side by side, the layer-shaped body ? having one or more cut prepregs A in which reinforcing fibers oriented in one direction are impregnated with a resin composition, the volume fraction of fiber is 45-65%, and at least a portion of the reinforcing fibers are segmented into a fiber length of 10-300 mm by a plurality of cuts, and the layer-shaped body ? having one or more base materials B in which reinforcing fibers having a fiber length in the range of 10-300 mm are impregnated with a resin composition.

Abstract: An intermediate base material is provided that is excellent in the conformity to three-dimensional shapes and that, when formed into a fiber reinforced plastic, develops good surface quality and high mechanical properties. According to one aspect, an incised prepreg is provided that has, in at least a partial region in a prepreg that contains unidirectionally oriented reinforcing fibers and a resin, a plurality of incisions that divide reinforcing fibers, wherein, in the case where a population is made up of the numbers of incisions contained in ten small circular regions of 10 mm in diameter randomly selected in the aforementioned region, a mean value for the population is 10 or greater and a coefficient of variation therefor is within 20%.