Patent ID: 8361265
Filing Date: 2013-01-29
Classification: B29B,B29C,B29K,B32B,C08J,Y10T

Abstract:
1. A method for producing a composite prepreg base comprising a raw prepreg base composed of a fiber sheet of discontinuous reinforcing fibers having a fiber length of 1 to 300 mm and arranged in one direction and a matrix resin impregnated into the fiber sheet, and an additional resin layer formed on at least one of the surfaces of the raw prepreg base, which comprises the steps of: (1-a) preparing a prepreg base comprising a fiber sheet of continuous reinforcing fibers arranged in one direction and a matrix resin impregnated at least partly into the fiber sheet, (1-b) forming an additional resin layer on at least one of the surfaces of the prepreg base prepared in the step (1-a), and (1-c) forming cuts into the prepreg base having the additional resin layer formed in the step (1-b) to form discontinuous reinforcing fibers having a fiber length of 1 to 300 mm from the continuous reinforcing fibers, wherein 1) a resin constituting the additional resin layer differs from the matrix resin, and a minimum viscosity of the resin constituting the additional resin layer, in a range from room temperature to a decomposition temperature, is lower than that of the matrix resin, or 2) a resin constituting the additional resin layer differs from the matrix resin, and a fracture toughness of the resin constituting the additional resin layer is higher than that of the matrix resin.