A method for producing a glass fiber-reinforced polyester resin composition using a twin-screw extruder, the resin composition comprising 10 to 60 mass% of (A) polyester resin, 40 to 70 mass% of (B) glass fiber, and 0 to 50 mass% of (C) other polymers or additives. The method is characterized in that the resin composition has a shear viscosity of 400–2000 Pa·s at 265°C and 91 s⁻¹; the method comprises: first step, mixing (A) and (C) using a first mixing unit; second step, adding (B) glass fiber and mixing using a second mixing unit; third step, reducing pressure at the vent, removing volatiles, applying pressure, and extruding from a die mounted on a die holder; and fourth step, cooling the strand leaving the die with water and cutting the strand using a pelletizer; and extrusion is performed such that the resin pressure in the die in the third step is 2–9 MPa.
Country Code: JP
Application Number: CN202380034594.5;TW112111339
