Prepregs, and processes for their production

The present invention relating to prepregs has the following constitution to achieve the above object. That is, a prepreg, comprising long reinforcing fibers [A], matrix resin [B] and a knitted fabric made from thermoplastic resin fibers [C], with the component [C] distributed near either or both of the surface layers. Moreover, the present invention relating to processes for production of prepregs has either of the following constitution to achieve the above object. That is, a process for preparing a prepreg, comprising the steps of impregnating long reinforcing fibers [A] with matrix resin [B], and bonding a knitted fabric made from thermoplastic resin fibers [C] onto one side or both sides of the intermediate product, or a process for preparing a prepreg, comprising the step of bonding matrix resin [B] formed as a film, a knitted fabric made from thermoplastic resin fibers [C] and long reinforcing fibers [A]. The prepregs of the present invention contain, therefore, are tacky and drapable, and the composite materials obtained by heating and forming the prepregs are high in heat resistance, and very high in impact resistance and inter-layer toughness. Furthermore, the prepregs are easy to produce and high in their latitude in availability of materials, this being industrially significant.