BOTTLE CAP

摘要

PURPOSE: A bottle cap for enabling a user to add an additive is provided to enable the user to easily open the bottle cap and to obtain the reliability of a product by installing a door for opening and closing the bottom of an inner cap. CONSTITUTION: A bottle cap for enabling a user to add an additive comprises: an inner cap(100) which is placed in an inlet port of a container(10) in a form of a receiving pipe(130) and has a door(110); and an upper cap(200) which is screwed with a screw part(11) and in which an inner flange(210) is integrally formed. The inner flange is pressed through a flange slope(212) while rotating with a screw. A secondary flange is added to the external diameter of the inner flange.