2.1 Desiccant raw material-silica gel
Silica gel is a highly active adsorption material, which is usually prepared by reacting sodium silicate and sulfuric acid and undergoing a series of post-treatment processes such as aging and acid foaming. Silica gel is insoluble in water and any solvent, non-toxic, tasteless, chemically stable, and does not react with any substances except strong alkalis and hydrofluoric acid. Silica gel desiccant has high adsorption performance, good thermal stability, stable chemical properties, and high mechanical strength.
Silica gel is also the only desiccant that has passed the US FDA certification and can be used in direct contact with drugs and food.
According to different packaging specifications of the desiccant product, the main types of silica gel are 0.5-1.5mm, 1-2mm, 1-3mm, 2-4mm.

2.2 Desiccant packaging-wrapping paper
Wrapping paper is a medium for qualitative and quantitative silica gel raw materials. Wrapping paper should have the following characteristics: 1. Air permeability 2. Tensile strength 3. Non-toxic and harmless;
The traditional desiccant packaging paper is mainly heat-sealing tea filter paper. With the continuous development of the desiccant application industry, the food and drug regulatory authorities of various countries have different degrees of recognition of the material, and more and more new packaging materials continue to appear, composite paper, Non-woven fabrics, non-woven paper, multi-layer composite paper, Aihua paper, Taiwek paper, OPP, etc., make the packaged desiccant products have their own characteristics, and the finished products are suitable for different use environments.