A liquid receptacle for rapidly lowering the temperature of a liquid contained
therein to a warm range suitable for human contact and maintaining the liquid in
the warm range for an extended period of time includes an inner vessel with an
open upper end and a closed lower end and a wall connecting the upper and lower
end. An insulated outer shell is spaced from the inner vessel to define an interstitial
chamber between the inner vessel and the outer shell. A phase change material occupies
the chamber and regeneratively absorbs thermal energy from the liquid to cool the
liquid and then releases the thermal energy back to the liquid to maintain the
temperature of the liquid.