At present, the more commonly used desiccant for electronic products is mineral desiccant and silica gel desiccant, but the moisture absorption rate of mineral desiccant and silica gel desiccant is low, some customers will also consult whether they can use calcium chloride desiccant, today we will discuss it together.
1. Why calcium chloride desiccant is less used in electronic products?
General circuit boards usually have copper (Cu), iron (Fe) and other metal components, calcium chloride contains halogen ions (chloride ion Cl). The solution containing halogen ions is more conductive and will promote oxygen absorption corrosion of metal components. However, this does not indicate that the use of calcium chloride desiccant will necessarily corrode the metal components in electronic products.
The necessary condition for the corrosion of metal by calcium chloride desiccant is the direct physical contact between calcium chloride and metal components. Although calcium chloride contains chloride ions, it is not volatile and cannot corrode the nearby metal components through the air pathway. Therefore, only under two conditions, calcium chloride desiccant may corrode the metal components in electronic products. One is that the desiccant surface is covered with calcium chloride dust, and the other is that the drying package is squeezed and leaked during the transportation process. Both of these two cases are greatly related to the production environment and product quality of calcium chloride desiccant.
2. Under what circumstances can calcium chloride desiccant be used in electronic products?
- There is physical isolation in the product design, and the calcium chloride desiccant will not directly contact with the metal original parts in the product. For example, in the case of headphones, besides the physical isolation of the headphone shell, there is a diaphragm inside, and the metal components are generally processed by electroplating, and they have corrosion resistance.
- There is enough place for desiccant in the packaging material of the product, and the desiccant will not be in direct contact with the product. Our company has created a successful case for the display screen of a famous Korean electronic brand.
- It is necessary to put desiccant in the outer packing box of the product and there is enough position.
- Calcium chloride desiccant is used in the container to prevent moisture in the container as a whole.
To sum up, calcium chloride desiccant is not completely not applicable to electronic products, but when choosing calcium chloride desiccant products, you must examine the production environment (whether it is a clean workshop) and product quality (whether the packaging materials used have the risk of leakage) of the products.