Apparatus for controlled initiation of fluid-flow from an inverted container

An apparatus for containing a fluid, and for controlling release and flow of the fluid contained therein, the apparatus comprising:

• a container having a mouth, a neck, and a body, an inner surface of the neck including a continuous circumferential sealing region and a resistance stop;
• and
• a barrier flap attached to a narrow portion of the inner surface of the neck of the container by a hinged attachment located directly opposite to the resistance stop, the barrier flap being thereby hingedly pivotable between a closed position and an open position, the resistance stop being able to hold the barrier flap in the closed position,
• the barrier flap in the closed position being cooperative with the continuous circumferential sealing region and forming a seal therewith, and the barrier flap in the open position conforming at least partially to the inner surface of the neck so as to allow substantially unhindered flow of the liquid from the container,
• the barrier flap being releasable from the resistance stop by squeezing the neck in a direction substantially perpendicular to a line connecting the hinged attachment and the resistance stop, thereby arcing the barrier flap, moving the resistance stop away from the barrier flap, and freeing the barrier flap to pivot to the open position, the hinged attachment being configured so as to resist detachment from the neck when the neck is distorted due to squeezing.