Cap and tube container including same

A cap fittable over a mouth of a container, the cap comprising:

• a molded plastic product;
• and
• a molded paper product comprising paper as a primary material and joined to the molded plastic product, wherein
• the molded plastic product comprises a lid configured to open and close the mouth;
• a joining section, to which the molded paper product is joined;
• a receiving section joined to the joining section and
• a cylindrical portion extending from the receiving section;
• the joining section is a plate having a shape of a regular polygon,
• the receiving section has a shape of a regular polygon identical to the shape of the joining section, and
• the cap has a shape of a polygonal prism including the receiving section and side plates standing on sides of the regular polygon;
• the lid is cylindrical with an internal thread cut in an inner surface of the lid to correspond to an external thread cut on an outer surface of the mouth or cylindrical with an external thread cut on an outer surface of the lid to correspond to an internal thread cut in an inner surface of the mouth,
• the lid is bonded to a central position of the joining section with an axis of the lid extending in a direction orthogonal to a surface of the joining section;
• the joining section is bonded to a first end of the lid, the first end of the lid is opposite a second end of the lid, the second end of the lid opens and closes the mouth and used to join to the molded paper product.