Insulating glass molecular sieve desiccant classification
Molecular sieve desiccant is a hydrated alumino silicate crystal with a (tetrahedral) skeleton structure, including 3A, 4A, 5A, etc. The pore diameter is generally between 3~10×10^(-10)m. Since the space of insulating glass is air, it is only necessary to use the molecular sieve desiccant with the ability to adsorb water vapor, instead of adsorbing nitrogen and oxygen. The effective pore size of 3A molecular sieve is 3×10^(-10)m, which has the characteristics of adsorbing water vapor but not nitrogen and oxygen. Therefore, 3A type molecular sieves are widely used in the insulating glass industry.
3A only adsorbs water, not ethylene, acetylene, ammonia, carbon dioxide and larger molecules.
In the past, type 4A molecular sieve was used as a desiccant, but it is not currently used because it can adsorb nitrogen and oxygen. The gas in the insulating glass space layer is sealed. If the desiccant can adsorb nitrogen and oxygen, the air pressure in the space layer of the insulating glass will change, especially when the temperature and humidity change, the adsorbed nitrogen and oxygen will also change, and the air pressure in the space layer will fluctuate. Very bad for insulating glass.
How to install desiccant for insulating glass fogging, desiccant is mainly suitable for water adsorption in interlayer gas, and continuously absorbs water entering the spacer layer during its shelf life; avoid glass fog, keep clean and transparent even at very low temperature, improve Thermal insulation performance, reduce energy consumption and fully extend shelf life. We recommended to use 3A, because the pore size of 3A molecular sieve is only 3 angstroms, which is the smallest pores in the molecular sieve, and can only absorb water and cannot absorb any other components in the air.