FUEL CAP

摘要

The present invention provides a fuel cap configured so as to suppress a reduction in gas permeability within a housing caused by the wetting of an adsorption material, thereby enabling fuel vapor to be appropriately released. A fuel cap (100) includes a housing (10) having an inner space in which vapor generated in a fuel tank (50) flows upward from below. A granular adsorption material (AD) is disposed within the inner space of the housing (10). A lower gas-permeable layer (31) is disposed below the adsorption material (AD), and an upper gas-permeable layer (34) is disposed above the adsorption material (AD). A lower porous member (32) is disposed between the adsorption material (AD) and the lower gas-permeable layer (31). The lower gas-permeable layer (31), the lower porous member (32), and the upper gas-permeable layer (34) each have a porous structure. The density of the lower porous member (32) is lower than that of the lower gas-permeable layer (31) and that of the upper gas-permeable layer (34).