There are often many customers who ask how long your desiccant can last for a long time. In fact, the desiccant has a period of transportation and storage from the time of production to the end of use. It needs to be packaged with certain packaging materials to ensure the desiccant is intact and effective. Since the desiccant functions by adsorbing water vapor in the air, the outer packaging material of the desiccant (different from the packaging material) must have the properties (such as a certain strength and toughness) of the ordinary packaging material, Seal the package and have a certain barrier to water vapor. The indicator for measuring the water vapor barrier property of a material is water vapor transmission rate (WVTR or WDD), which refers to the amount of water vapor that penetrates the material under a certain temperature and humidity condition. The ratio of surface area of materials, in SI units, is g/m2•24h. The smaller the water vapor transmission rate of the packaging material, the better the barrier property, and the longer the drying time of the desiccant in the package; the greater the water vapor transmission rate, the worse the barrier property, and the shorter the drying time of the desiccant in the package. Of course, the shelf life of the actual desiccant is also related to factors such as the size of the package, the preservation environment, and the quality of the seal. The user of the desiccant can choose the appropriate packaging method according to his actual situation.