Patent ID: 7735666

Claim:
An open/close cap which is screwed to a mouth portion of a pouring spout of a packaging container and adapted to open the mouth portion, the open/close cap comprising: a cap body screwed to an outer peripheral surface of the mouth portion; a band attached to the cap body so as to extend in a circumferential direction thereof so as to be engaged with the pouring spout; a contact preventing portion provided for the outer peripheral surface of the cap body so as to extend outward from the outer peripheral surface thereof, the contact preventing portion having a shape inclining downward so that an extending lower end portion thereof has a diameter equal to at least an outer surface of the band for preventing an application of an external force to the band; and a band shape maintaining member integrally formed on the cap body and projecting downward from a lower end surface of the cap body, the band shape maintaining member positioned to prevent the band from being pushed radially inward of the open/close cap, the band shape maintaining member with an outermost diameter defining a predetermined gap between the band shape maintaining member and an inner surface of the band, wherein, the band is provided with at least one portion for separating the band in the circumferential direction, end portions of the separated band are connected to each other by a connection piece, which connection piece is to be cut off, at that one portion, a protruded portion is formed to an inside of the band so as to project toward the pouring spout, when the open/close cap is rotated in an opening direction with respect to the pouring spout, a forward side of the band between which the connection piece is snapped when rotated together with the cap body and a rear side of the band is prevented from rotating by engagement of the protruded portion with a portion of the pouring spout, the connection piece is cut off in the circumferential direction thereof by a stress of the band generated by the engagement, and the band is positioned below the lower surface of the cap body so as to be attached to the lower portion of the cap body by a coupling piece, so that when the cap is removed, the band is removed together with the cap body, the cap body remaining attached to the band by the coupling piece with the coupling piece connecting the inner surface side of the band and the lower surface of the cap body.