Canister

A canister comprising:

• a casing including a gas passage which extends from a first passage end formed with a charge port to let in fuel vapor and a purge port to let out the fuel vapor, to a second passage end formed with an atmospheric air port to let in air, and which includes a heat storing and adsorbing chamber;
• a granular adsorbing material held in the heat storing and adsorbing chamber;
• and
• a granular heat storing material held in the heat storing and adsorbing chamber together with the granular adsorbing material, the granular heat storing material containing capsules each including a phase-change material enclosed in a multilayer outer shell including an inner layer of a hydrophobic resin and an outer layer of a hydrophilic resin covering the inner layer.