Method for forming a security stopper-capsule and applying it to containers with a threaded mouth, and the stopper-capsule obtained thereby

A method for forming a closure and security device (22) comprising a screw stopper (10A) and a security capsule (16A) and applying it to containers provided with an externally threaded circular mouth, the method comprising the following steps:

• connecting to a metal stopper, destined to become a screw stopper once applied to the container (20), a capsule-forming foil (12) in such a manner as to provide the stopper (10) with a skirt (16) projecting by a determined portion from the free edge of the stopper (10), to obtain a stopper-skirt combination (18;
• 18A;
• 18B);
• applying the stopper-skirt combination (18;
• 18A;
• 18B) to the mouth of the relative container (20);
• making the skirt (16) rigid with the container (20) by known capsule techniques, depending on the type of foil used, to obtain a stopper-capsule (22);
• characterized in that, before making the skirt (16) rigid with the container (20), the stopper (10) is rolled to form on its lateral wall a thread matching the external thread on the mouth of the container (20).