Low Emission Glass, also known as Low Emission Glass. It is a type of coated glass that not only has high visible light transmittance, but also has strong infrared blocking properties, which can play a dual role of natural lighting and thermal insulation and energy conservation. After use, it can effectively reduce the outdoor heat dissipation and loss in winter, and also block the secondary radiation of outdoor objects heated by solar radiation in summer, thereby achieving the goal of energy conservation and consumption reduction. At the same time, Low-E glass has a high transmittance in the visible light band, which can make more use of natural lighting indoors, catering to the psychological desire of modern urbanites to return to nature, and saving lighting electricity. Low-E glass is divided into two types according to production and manufacturing processes: offline Low-E glass and online Low-E glass.
There is a significant difference in the composition and structure of the film layer, production process, manufacturing equipment, etc. between the two films, and there are also some differences in the performance characteristics of these two films. Below is a brief explanation of this.
Online Low-E glass is a functional film with low radiation performance formed on the surface of the glass strip on the float glass production line through equipment modification, chemical vapor deposition process, and specialized materials. The Low-E glass produced by this process is called online Low-E glass, and its film material is semiconductor oxide. The product only has two colors: cyan and colorless. Colorless products often appear slightly yellowish due to material reasons and film thickness.
Offline Low-E glass generally adopts a vacuum magnetron sputtering coating process, where multiple composite films are deposited on the surface of the glass to achieve Low-E function. The main functional film layer in the film layer is generally a silver (Ag) film, while other film layers are auxiliary films that strengthen connections and protect the main film. According to the different types of Ag films, they can be further divided into several different product categories, including single Ag, double Ag, and improved single Ag, with a variety of colors available for selection.
In developed countries such as Europe and America, there are corresponding laws and regulations that require owners and manufacturers to use Low-E glass and make it into a hollow form in order to achieve the energy-saving indicators specified in national laws and regulations. Beijing, Shanghai, Guangzhou, Shenzhen, Dalian, Shenyang and other cities in China have also formulated regulations and implemented similar regulations, encouraging homeowners to use Low-E products to promote energy conservation and environmental protection, improve air quality, and improve living environments. Each country and region formulates specific technical indicators for energy conservation of glass products based on local needs and consumption levels. If the energy-saving index is slightly higher, offline Low-E glass is generally required to meet the requirements, otherwise, it can be freely selected. Because offline Low-E glass saves about 8% more energy than online Low-E glass.
