| 摘要 |
<p>PROBLEM TO BE SOLVED: To dehumidify the inside of a box or the like having breathing action for a long period of time by providing an air passable body formed so that the average pore diameter and the moisture permeability of a waterproof membrane on the outer side of a vessel may be larger than those of a waterproof membrane on the inner side of the vessel. SOLUTION: On sucking action, fresh air is sucked in until the inner pressure of a box 10 and the fresh air are balanced. After that, in the case the vapor concentration in the fresh air is higher than that in the box 10, vapor is transferred to the room side 10c. At this time, since the average pore diameter and the moisture permeability on the box 10 side are smaller, the transfer of vapor is slow. In the case the vapor concentration on the room side 10c is higher than that of the fresh air, vapor on the room side 10c is transferred to the fresh air side 10b. In this case, the moisture permeability of a waterproof membrane near the fresh air side 10 is larger than that of a waterproof membrane on the room side 10c and besides, the vapor concentration on the fresh air side 10b does not become higher even when vapor on the room side 10c is discharged, so that the transfer of vapor is promoted.</p> |
