Variety and Property

Online Low-E glass has a good processing performance, which can be transported, stored, tempered, hot-bending and laminated as ordinary glass, The delivery and patch are also convenient.

Because of the constraints of offline Low-E glass crafts and glass film structure, it can not have monolithic use, can not be late tempered, laminated, even produce hot-bending glass. And offline Low-E glass can't exist independently in the air, so it is difficult to meet the requirements of the patch in construction industry.

Film Stability

Online Low-E Glass is produced in float glass tin bath, at this time the temperature is relatively high so it can maintain a fresh state and good reactivity, the film is very strong by combining the chemical bond with glass. In addition, it is composed of semiconductor oxide, which has a good chemical stability and a higher hardness than the glass body, so the film is termed as "Rigid Film".

Offline Low-E glass is used magnetron sputtering process, single silver or double silver functional film is formed on the surface of the glass. The two sides of the silver should be coupled with a multilayer dielectric film. This film has poor firmness and the silver is easily oxidized, which belongs to the "Soft Film". Offline Low-E glass should be processed to hollow glass in a short time, and the edge of the film should be removed in the composition process. Due to the weak respiration of hollow glass, water vapor, sulfide, oxide can enter the cavity easily, leading to the gradual loss of thermal insulation performance and discoloration in the appearance of offline Low-E glass, so it must be processed into hollow glass in a very short period of time. With this feature shelf life of the best product sold by the current offline manufacturers is only 10 years.

Energy Saving and Durability

Online Low-E glass is used stannic oxide semiconductor film layer, the radiation rate of the glass is 0.10 to 0.20. Because of good chemical stability of stannic oxide semiconductor layer, it can keep the low radiation rate and heat transfer coefficient K value unchanged forever. Due to the good stability of the film layer,the performance of online Low-E glass can never decay whether used single or combined with hollow glass.

Offline Low-E glass is used metallic silver as functional radiation film of far infrared thermal radiation, its initial rate can reach 0.1 to 0.15, which is similar to offline heat transfer coefficient K value at the beginning. But the contaction between silver and micro-sulfur and oxygen in the air will occur chemical reaction, once the film has slight oxidation, its radiation rate will be significantly large, thus leading to the increase of heat transfer coefficient K value in the glass, meanwhile, its thermal insulation performance becomes bad, if too serious, it can even cause the discoloration of glass film.