Patent ID: 8920695

Claim:
A method of producing a liquid crystal polyester composition using a twin-screw extruder, the method comprising: supplying a liquid crystal polyester to a supply port of the twin-screw extruder; introducing a filler other than fibrous fillers to a first addition port of the twin-screw extruder and introducing a fibrous filler to a second addition port of the twin-screw extruder, the first and second addition ports being located downstream of the supply port; melt-kneading the liquid crystal polyester, the filler other than fibrous fillers and the fibrous filler together using a screw of the twin-screw extruder to produce a liquid crystal polyester composition, the screw being provided with kneading portions on the upstream side and downstream side of the first addition port, the kneading portion provided nearest to the first addition port on the downstream side thereof having a screw configuration which does not use a reverse kneading disc; and extruding the melt-kneaded liquid crystal polyester composition from the twin-screw extruder, wherein a resin temperature of the liquid crystal polyester after being kneaded in the kneading portion provided nearest to the first addition port on the upstream side thereof satisfying formula (1) shown below: FT−100(° C.)≦ T 1≦FT+20(° C.) (1) wherein a resin temperature of the liquid crystal polyester after being kneaded in the kneading portion provided nearest to the first addition port on the downstream side thereof satisfying formula (2) shown below: FT−100(° C.)≦ T 2≦FT+30(° C.) (2), and wherein T 1 represents a temperature of the liquid crystal polyester after kneading, T 2 represents a temperature of the liquid crystal polyester after kneading, and FT represents the flow starting temperature of the liquid crystal polyester.