Abstract: A polyphenylene sulfide (PPS) molded board reinforced with 15-85 wt. % of glass fibers (GF) having a length of at least 5 mm is provided. The molded board is useful as an insulating substrate of a printed circuit board. The printed circuit board is prepared by compressing under heating a mixture or laminate of PPS and GF to form a composite molded board and, at or after the compression step, bonding a metallic foil to a surface the composite molded board. The printed circuit board is excellent in mechanical properties such as impact resistance, thermal properties such as heat distortion temperature and solder resistance, and adhesion between the insulating substrate and the metallic foil.

Abstract: A carbon fiber-reinforced moldable sheet is provided. The moldable sheet comprises a thermoplastic resin and at least two reinforcing agents differing in the length/diameter ratio, which are incorporated with the thermoplastic resin. One reinforcing agent (A) contained in the composite sheet is a carbon fiber having a length/diameter ratio of 200 to 30,000 and the other reinforcing agent (B) is a fibrous and/or powdery reinforcer having a length/diameter ratio of less than 50, and the contents of the reinforcers (A) and (B) in the moldable sheet are 5 to 30% by volume and at least 5% by volume, respectively, the sum of the contents of the reinforcing agents (A) and (B) being in the range of from 20 to 50% by volume. The reinforcing effect of the carbon reinforcing fiber (A) is enhanced by the fibrous and/or powdery reinforcing agent (B) filled among spaces of reinforcing fibers (A). Therefore, molded articles made therefrom are excellent in mechanical properties and appearance and light in weight.

Abstract: A method for producing thermoplastic resin molded articles is disclosed. The method comprises heating a sheet comprising a crystalline thermoplastic resin, which is crosslinked to a degree of more than about 5%, to a temperature that is higher than the melting point of the crosslinked resin but below the decomposition temperature thereof. The thus pre-heated sheet is press-molded under a pressure of about 50-1,000 kg/cm.sup.2 by a pair of press mold dies, which are maintained at a temperature below the melting point of the crosslinked resin.