1, quicklime desiccant; The main ingredient of quicklime desiccant is calcium oxide, and its water-absorbing capacity is realized through chemical reaction, so the water-absorbing has irreversibility. No matter how high or low the humidity of the external environment is, it can keep the moisture absorption capacity greater than 35% of its own weight, and it is more suitable for low temperature preservation, with excellent drying and moisture absorption effect, and the price is low. It can be widely used in food, clothing, tea, leather, shoes, electrical appliances and other industries. At present, this type of desiccant is used in the most common "snow cake". However, lime desiccant has strong alkali corrosiveness, often happens to hurt the eyes of children or old people, has been gradually eliminated. 2, silica gel desiccant Shanghai Yixuan desiccant? Shanghai Yixuan desiccant; this desiccant is permeable sachet packing of different varieties of silica gel, the main raw material silica gel is a kind of water-containing silica with high microporous structure, non-toxic, tasteless, odorless, chemically stable, with strong hygroscopic properties. Therefore, it is widely used in instruments, meters, equipment, leather, bags, shoes, textiles, food, drugs and other storage and transportation to control the relative humidity of the environment, to prevent moisture, mold and corrosion. For example, xylitol is used, and it is also the only desiccant recognized by the European Union. 3, montmorillonite desiccant; this desiccant adopts pure natural raw material bentonite, green, non-toxic, tasteless, no damage to human body. It has good adsorption performance at room temperature and general humidity, with adsorption activity, static damping and odor removal. Not only adsorption speed, high adsorption capacity and non-toxic, odorless, no contact corrosive, no environmental pollution, especially in food packaging, harmless to humans. Scope of application: Widely used in products that can not be sealed with oil, gas phase sealing, such as: optical instruments, electronic products, medical care, food packaging and dry air sealing of military products and civil products. 4, calcium chloride desiccant; calcium chloride desiccant main raw material calcium chloride is the use of high-quality calcium carbonate and hydrochloric acid as raw materials, through the reaction synthesis, filtration, evaporation and concentration, drying and other processes refined. White porous block, granular or cellular solid. Slightly bitter taste, odorless. Aqueous solution is colorless. Mainly used as raw material for the production of other calcium salts in inorganic chemical industry; also used as desiccant for gas, dehydrating agent for the production of alcohol, ester, ether and acrylic resin. It is used as calcium fortifier, curing agent, chelating agent and desiccant in food industry etc. 5, fiber desiccant; fiber desiccant is made of pure natural plant fiber through special process. Among them, especially the laminated fiber desiccant sheet is convenient and practical and does not occupy space. Its moisture-absorbing capacity reaches 100% of its own weight, which is incomparable to ordinary desiccant. In addition, the product is safe and hygienic with moderate price, which is ideal for many biological, health food and pharmaceutical products.