| abstract |
A purpose of the present invention is to obtain a polyester resin which has satisfactory injection moldability and excellent mechanical strength and which gives molded articles that can be rendered stably weldable with a laser by making portions of the molded articles have high laser-light transparency and controlling the dimensional properties of the molded articles. A polyester resin composition according to the present invention is characterized by having a crystallinity, as calculated by the following method with fast scanning calorimetry, of 15% or greater. Calculation method: Crystallinity calculated from a curve obtained using fast scanning calorimetry by heating the polyester resin composition from 30°C to 260°C at 10,000 °C/sec, holding it at 260°C for 0.1 second, cooling it to 80°C at 5,000 °C/sec, holding it at 80°C for 0.1 second, cooling it to -70°C at 5,000 °C/sec, and thereafter heating it to 260°C at 1,000 °C/sec. |