Patent ID: 7287658

Claim:
A polymeric container for holding a fluid and a gas, comprising: a top, a base, and an upstanding wall connected therebetween; said container having a volume; said base having: an annular outer ridge which protrudes away from said top, said outer ridge having a diameter and defining a plane upon which said container may rest; a dome connected to said outer ridge wherein said dome has a diameter of at least about 25% of the diameter of the outer ridge diameter and is disposed within said outer ridge, said dome protruding away from said top, said dome having an apex which resides between said top and said plane; and, a flexible annular joint connecting said outer ridge and said dome, said annular joint forming an inner ridge which protrudes toward said top; and, wherein when (1) the fluid is heated and the heated fluid and the gas are injected into said container, and (2) said top of said container is then sealed, and (3) the fluid and gas within said container are then allowed to cool while the dome remains protruding away from the top, during cooling said dome moves toward said top thereby reducing said volume of said container.