Hermetically sealed container and vacuum test substance-collecting container

A sealed container, which comprises

• a container with an end being closed and the other end being open, comprising a thermoplastic resin, and
• a stopper being detachable and capable of sealing the open end of the container, the stopper having a head portion capable of being grasped, a leg portion A extending downward from the head portion, extending along an internal wall surface of the open end of the container, and being capable of exerting a fitting force to the internal wall surface, and a leg portion B being extending downward from the head portion, the leg portion B having an external contact surface extending downward from the head portion, and the external contact surface contacts throughout an external wall surface of the open end of the container, and the external contact surface being capable of exerting a fitting force to the external wall surface, and
• the external contact surface having a deflection temperature, under a load of 0.45 MPa or 0.46 MPa, which is higher than a deflection temperature, under a load of 0.45 MPa or 0.46 MPa, of at least a portion of the container, which contacts the leg portion A of the stopper;
• wherein the leg portion A of the stopper is made of a thermoplastic elastomer or a thermosetting elastomer or the leg portion A has a surface layer comprising thermoplastic elastomer or a thermosetting elastomer at least at a portion contacting the internal wall surface of the container;
• and,
• wherein a position of the fitting force exerted between the leg portion A of the stopper and the internal wall surface of the container being greatest and a position of the fitting force exerted between the external contact surface of the leg portion B of the stopper and the external wall surface of the container being greatest are located at different positions in the longitudinal direction of the container.