DOUBLE WALL BLOW MOLDED BODY

PROBLEM TO BE SOLVED: To provide a double wall blow molded body having high cushionability in an initial period of compression, capable of preventing ribs from falling down by a compression load, and having high impact absorbability.SOLUTION: The first ribs 3 having a concaved groove shape concaved from a wall 1 to a wall 2 and the second ribs 4 having a concaved groove shape concaved from the wall 2 to the wall 1 are formed and both the ribs 3, 4 are substantially perpendicular to each other in a plan view. In the first ribs 3 and the second ribs 4, bottom walls 12, 15 are located in a substantially central position of the double wall and the bottom walls 12, 15 are welded each other in an intersecting part 16. It is preferable that the first ribs 3 and the second ribs 4 are meshed with each other. The first ribs 3 and the second ribs 4 have releasing inclinations, both the side walls 10, 11 of the first ribs 3 and both the side walls 13, 14 of the second ribs 4 overhang to the inside of the concave grooves respectively, come into contact with each other in the process of crushed deformation, hamper bending deformation of the other side and increase a resistant force to a compressing load, when the double wall blow molded body crushedly deforms by the compressing force acting in a thickness direction of the double wall.