| 摘要 |
<p>PROBLEM TO BE SOLVED: To exhibit excellent compression resistance and impact resistance by a constitution wherein approximately uniform thickness is provided on the outer peripheral side walls and a bottom and ridge parts thereof and as recessed parts or projected parts are formed on the outer peripheral side walls, it is extremely tough and no stress concn. occurs at a part when impact loading is applied by compression loading and falling down. SOLUTION: An opening part has a cylindrical container shape consisting of a polygonal, cylindrical, ellipsoidal and uncertain shapes and dimensional ratio of the depth of the outer peripheral side wall 11 to the square root of the area of the opening outer shape part is made 0.5 to 3. On the outer peripheral side walls 11 among peripheral side walls, deep recessed parts 10 being close to the inner peripheral side walls 15 or projected parts 10a projected outside are provided for hand hooking parts during delivering and the thickness of the outer peripheral side walls, a bottom sheet and ridge parts on these boundaries are prepd. by blow molding from a single parison with an approximately uniform thickness.</p> |
