| 摘要 |
PROBLEM TO BE SOLVED: To provide a container whose cap can be easily opened. SOLUTION: In such a PET bottle 1 that an inner ring 7 is in pressure contact with an inner peripheral surface 3a of a mouth 3 when a cap 5 with the inner ring 7 is screwed with the mouth 3 and fastened, a pressure contact region R where the inner ring 7 is in pressure contact with the inner peripheral surface 3a of the mouth 3 is smoother than other regions. |
