| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to ensure both high compression strength and content visibility for a lid body obtained by thermoforming a thin synthetic resin sheet.SOLUTION: In a lid body B including a top plate portion 10, a sidewall portion 20, and a flange portion 30 and obtained by thermoforming a transparent synthetic resin sheet, the sidewall portion 20 includes an appropriate number of reinforcement structures 21 each including a depressed portion 22 having an equal width from a lower end to an upper end, and a longitudinal reinforcement rib 24 protruding outward from a bottom surface 23 of the depressed portion 22 with a lower end surface 25 of the depressed portion 22 used as a base thereof. A wall surface of the sidewall portion 20 is flat at locations other than those where the reinforcement structures 21 are formed. |
