A pressure-responsive valve exhibiting unusual restoring force includes an elastically deformable diaphragm having a plurality of non-intersecting, non-meeting, separate arcuate slits, each slit having a base which is intersected by at least one other slit, and each slit being out of intersecting relation with its own base.

The invention concerns a device comprising a flask (1) with variable internal volume having a rigid neck (5) wherein is arranged the body (3) of a dispensing head (2) ending in a conduit (41) discharging the liquid and containing a microporous pad (6) for generating a head loss regulating the liquid flow pushed therethrough into a distribution chamber (31) communicating with said conduit. The pad is advantageously made of a material inert with respect to the liquid and combined with an antibacterial filtering element (9) preventing outside air from entering the flask. It evenly occupies the body (3) over the whole cross-section of the liquid passage.

A tubular container for adhesive material includes a substantially tubular body and a relatively rigid spout. An insert disposed in the spout hinders the intrusion of air through the spout. A plate is positioned so that the edge of the plate abuts the shoulder of the tubular body. The plate is supported by the insert at locations spaced from the edge of the plate. The exertion of pressure on the center of the plate causes the edge of the plate to be separated from the shoulder of the tubular body, thereby defining a passage for adhesive material.

A pressure-responsive valve exhibiting unusual restoring force includes an elastically deformable diaphragm having a plurality of non-intersecting, non-meeting, separate arcuate slits, each slit having a base which is intersected by at least one other slit, and each slit being out of intersecting relation with its own base.

The invention relates to a container for flowable or otherwise extrudable materials, the container having a discharge barrier which comprises a dividing wall dividing the container space into an outer chamber which is in communication with a dispensing opening of the container and into a storage chamber in which the contents can be subjected to pressure for dispensing from the opening and can thereafter again be relieved of pressure. The dividing wall is formed with a membrane section having at least one valve opening which upon pressure loading of the membrane section from the side of the storage chamber opens against a restoring force exerted by a membrane mounting and which upon relief from pressure automatically closes again under the restoring force. The dividing wall is also formed with a holding element which is connected to the container in a manner that takes up manufacturing tolerances. Additionally, the dividing wall is formed with the mounting for its membrane section, the mounting being formed so as to be of relatively stable shape and being itself carried by the holding element. In the result, the mounting carries the membrane section in a manner largely uninfluenced by the connecting conditions between the holding element and the container.