SPOUT STOPPER AND PACKAGING CONTAINER

摘要

Provided are: a spout stopper that prevents lowering of the sealing performance between a stopper body and a cap without causing degradation of the liquid cut performance of the stopper body; and a packaging container using the spout stopper. A spout stopper comprises: a stopper body that has a cylindrical side wall; and a cap that is fitted to the stopper body from one end, specifically an upper end, of the side wall. A protruding part that protrudes outward from the side wall is formed at an upper edge of the side wall, and a top surface of the upper end of the side wall is in surface contact along the entire circumference with a prescribed contact surface inside the cap in a state where the cap has been fitted to the side wall.