Patent attributes
A container including a finish defining an opening at a first end of the container that provides access to an internal volume defined by the container. A base portion of the container includes a diaphragm that is concave relative to an exterior of the container. The diaphragm extends from a standing surface of the container to a center push-up portion of the base portion. The standing surface is at a second end of the container opposite to the first end. The diagram is configured to move from an as-blown first configuration to a second configuration in which the diaphragm is closer to the first end as compared to the first configuration in order to reduce residual vacuum within the container. The diaphragm is generally hemispherical in cross-section when in the second configuration.