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The moisture-proof material of the PE plastic bag is a key factor affecting moisture-proof packaging. Any material that can delay or prevent external moisture transmission can be used as a moisture-proof barrier to carry out moisture-proof packaging.  
Some packaging materials, such as paper products, which are poor moisture-proof performance, if used in moisture-proof packaging, must be treated with moisture-proof, and their methods have the following:  
A, wax coating, wax is a good moisture-proof material, melting wax, so that paper is immersed in wax liquid.  
B, coating coating, coating mainly have oil, varnish, etc.  
C, plastic coating, the main raw material is polyvinyl butyral, which is thermosetted plastic, dissolved in ethanol, and then coated with rubber roller, and then dried.  
Packing of a layer or multi-layer moisture-proof material, such as asphalt paper, kraft paper, wax paper, aluminum foil, plastic film, etc., such as metal, ceramics, glass, composite materials, such as asphalt paper, kraft paper, wax paper, aluminum foil, plastic film, etc. Wait for a container, package drying products, and then seal the mouth of the container, and the moisture can no longer enter.  
The appropriate amount of desiccant is added to the sealed package, so that the moisture of the internal residue and the moisture through the moisture-proof barrier layer are absorbed by the desiccant, thereby preventing the induction of moisture, it should be noted that this type of packaging needs Use. Moisture-proof materials with small moisture permeability, otherwise appropriate