The present invention includes a canister including an adsorption chamber. An adsorption material and a heat storage material are disposed within the adsorption chamber. The heat storage material is molded from a mixture of a plurality of microcapsules and a binder. Each of the microcapsules contains therein a heat-change material. The heat storage material is prevented from moving relative to the chamber wall of the adsorption chamber in at least one of two directions perpendicular to each other.