Closure, combination container and closure system, and method of using the same

A combination container and closure system comprising:

• a container having a generally annular neck defining a container opening having a central axis, the neck having a top edge and inner and outer surfaces;
• and
• a closure comprising:
• an annular top wall having opposed inner and outer surfaces;
• a generally annular skirt extending downwardly from the inner surface of the top wall, the generally annular skirt having opposed outer and inner surfaces, the inner surface of the generally annular skirt engaging the outer surface of the neck of the container;
• and
• an elastic annular seal member extending downwardly from an inner surface of the top wall, the annular seal member engaging the inner surface of the neck of the container, wherein the elastic annular seal member comprises an inner surface, an outer surface, and an apex, wherein the outer surface of the elastic seal member is generally parallel to the central axis, and wherein the inner surface of the elastic seal member comprises a first section generally parallel to the central axis, and a second section tapered outwardly to meet the outer surface at the apex.

A method for forming a closed container, comprising:

• providing a container having a generally annular neck defining a container opening having a central axis, the neck having a top edge and inner and outer surfaces;
• providing a closure comprising:
• an annular top wall having opposed inner and outer surfaces;
• a generally annular skirt extending downwardly from the inner surface of the top wall, the generally annular skirt having opposed outer and inner surfaces, the inner surface of the generally annular skirt adapted to engage the outer surface of the neck of the container;
• and an elastic annular seal member extending downwardly from an inner surface of the top wall, the annular seal member adapted to engage the inner surface of the neck of the container, wherein the elastic annular seal member comprises an inner surface, an outer surface, and an apex, wherein the outer surface of the elastic seal member is generally parallel to the central axis, and wherein the inner surface of the elastic seal member comprises a first section generally parallel to the central axis, and a second section tapered outwardly to meet the outer surface at the apex;
• and
• disposing the closure over the neck of the container such that the inner surface of the closure seals against the outer surface of the neck of the container, and the outer surface of the annular seal member seals against the inner surface of the neck of the container.