Patent ID: 8992811
Filing Date: 2015-03-31
Classification: B29C,B29K,D04H,D06M,Y10T

Abstract:
1. A method of manufacturing a shaped product including carbon fibers and a thermoplastic resin, the method comprising: (1) a process of preparing a random mat which includes the carbon fibers including carbon fiber bundles with an average fiber length of 5 mm to 100 mm and the thermoplastic resin; (2) a process of impregnating the thermoplastic resin into the carbon fiber bundles by heating and pressurizing the random mat up to a temperature of a melting point of the thermoplastic resin or more and less than a decomposition temperature of the thermoplastic resin in a case where the thermoplastic resin is crystalline, or up to a temperature of a glass transition temperature of the thermoplastic resin or more and less than a decomposition temperature of the thermoplastic resin in a case where the thermoplastic resin is amorphous, before or after arranging the random mat within a mold; (3) a process of pressurizing and molding the random mat in which the thermoplastic resin is impregnated into the carbon fiber bundles within the mold at a pressure ranging from 0.1 MPa to 20 MPa; and (4) a process of taking out the shaped product obtained from the mold, wherein the processes (1) to (4) are performed in this order, in the random mat, the carbon fibers have a fiber areal weight ranging from 25 g/m the carbon fiber bundles include carbon fiber bundles (A) having the carbon fibers of not less than a critical number of single fiber defined by equation (1), and carbon fibers (B) having the carbon fibers of less than the critical number of single fiber, in which a ratio of the carbon fiber bundles (A) is 20 Vol % or more and less than 99 Vol % based on a total amount of the carbon fibers in the random mat: wherein, D represents an average fiber diameter (μm) of single carbon fiber.