Automobile fuel tank

An automobile fuel tank having an outer wall composed of a main body of a multiple-layered synthetic resin, wherein

• said outer wall includes at least an outer body layer, an outer adhesive layer, a barrier layer, an inner adhesive layer, and an inner body layer, said outer body layer and said inner body layer are formed of a high density polyethylene (HDPE) as a main ingredient, which has physical properties:
• (1) a modulus of elasticity of 1100 to 1400 MPa at 23° C.;
• (2) a modulus of elasticity of 340 to 430 MPa at 65° C.;
• (3) a modulus of elasticity of 400 to 510 MPa at 23° C. after being immersed in Fuel D for 200 hours at 65° C.;
• (4) a Charpy impact strength of 7 to 14 kJ/m2 at −40° C.;
• (5) a full-notch creep test (FNCT) result of 50 to 300 hours at 80° C.;
• (6) a melt flow rate (MFR) result of 4 to 6 (g/10 minutes) at 190° C. and a load of 21.6 kg;
• and
• (7) a melt tension of 18 to 25 g when a sample that has been melted at 210° C. is extruded from a nozzle with a diameter of 2.095 mm and a length of 8 mm at an extrusion rate of 15 mm/min, and drawn at a take-up speed of 7.5 m/minute, and
• each of said outer adhesive layer and said inner adhesive layer is composed of a synthetic resin having adhesiveness against both said high density polyethylene (HDPE) and said barrier layer, and
• said barrier layer is composed of a synthetic resin through which fuel oil is hard to permeate.