A packaging bag has a bottom member folded in half along a folding line and sandwiched between two body members. Body seal portions with surfaces of the body members joined along left and right circumferential edge portions of the packaging bag are formed on a side above the folding line. A bottom seal portion with an inner surface of the bottom member joined to the inner surfaces of the body members is formed on a side below the folding line. An unsealed portion surrounded by the body seal portions and the bottom seal portion accommodates a content. Resin layers of the body members and the bottom member are formed of a polyethylene-based resin film. Boundary portions between the bottom seal portion and the unsealed portion have a convex shape toward the upper side of the packaging bag near a part in contact with the body seal portions.

The present invention generally relates to a spout and to flexible and refillable containers comprising such spouts, designed to improve the functionalities of known spouts. The spout according to the present invention has a design that allows a tight fit between the spout and an additional container to which the flowable product is transferred from the refillable container comprising the spout.

A system comprises a container, a water-activated heating element, and a towel. Water can be poured into the container to activate the water-activated heating element. The towel can be placed in the container with the activated water-activated heating element.