Delaminatable container, method of checking the same for a pinhole, and method of processing the same

A delaminatable container, comprising:

• a container body having an outer shell and an inner bag, the inner bag delaminating from the outer shell with a decrease in contents and being shrunk;
• and
• a valve member regulating entrance and exit of air between an external space of the container body and an intermediate space between the outer shell and the inner bag, wherein the container body includes a storage portion to store the contents and a mouth to discharge the contents from the storage portion,
• the outer shell includes a fresh air inlet communicating the intermediate space with the external space in the storage portion, and
• the valve member includes an axis inserted into the fresh air inlet, a lid provided on a side of the intermediate space in the axis and having a cross-sectional area greater than that of the axis, and a locking portion provided on a side of the external space in the axis and preventing entrance of the valve member to the intermediate space,
• wherein the lid has an end section having a tapered shape, and
• a boundary between the lid and the axis has a curved shape bulged towards outside.