Common safety glass and its characteristics

In daily life and production, ordinary glass cannot meet the requirements for safe use. Safety glass is made by processing ordinary glass. The safety glass on the market is just a general term because there are several types of safety glass. Below, we will introduce the safety glass available on the market.

1. Tempered glass: It is glass that is rapidly cooled after being heated to a certain temperature or specially treated with chemical methods. Generally, on the basis of the original ordinary float glass, the glass is heated to the softening point temperature and then quenched to generate tensile stress in the center of the glass and compressive stress on the surface of the glass, achieving uniform stress balance.

The varieties of tempered glass include chemical tempering, also known as ion tempering and physical tempering. The characteristic of chemically tempered glass is that the sodium ions on the glass surface are replaced by larger ions such as potassium ions, and it is made through a certain process at a temperature of around 400 degrees. Chemical tempered glass can be cut, bent, etc., but the strength of the glass after high-temperature processing will be affected. The initial strength of chemically tempered glass can reach 6-7 times that of the original glass, but its performance deteriorates with increasing use time. Due to the particularity of ion exchange, it is mostly used on ultra-thin glass.

The characteristic of physically tempered glass is high strength, and its general strength can reach about 4 times that of ordinary flat glass. Safety tempered glass immediately splits into small particles without sharp angles after breaking. The disadvantage is the possibility of self violence. There are also two types of physically tempered glass, fully tempered glass and heat strengthened glass. Heat strengthened glass does not self destruct, but its strength is only about twice that of ordinary glass. Mostly used in high-rise buildings to improve wind pressure resistance. Heat strengthened glass is not considered safety glass.

2. Laminated glass: Laminated glass is a glass product made of one layer of glass, one or more layers of glass, and a layer of plastic material sandwiched in between. Laminated glass is a material that serves to bond and isolate between glass or between glass and plastic materials, giving laminated glass impact resistance, sunlight control, and sound insulation. The characteristic of laminated glass is safety - even if it breaks, it will not cause harm to people, such as car windshields. Block UV rays and reduce object fading. PVB film can reduce over 99% of ultraviolet radiation. The disadvantage is that it reduces the lighting performance and increases the weight of the glass.

3. Coated glass: Coated glass, commonly known as heat reflective glass, includes two varieties: sunlight controlled coated glass and low emissivity coated glass (Low-E) glass. The principle of coating is to apply a layer of metal or metal oxide/nitride film on the surface of the original glass to reduce the shielding coefficient of the glass. Also known as low emissivity glass, 'Low-E' glass, it is a coated glass with high reflectivity for far-infrared radiation in the wavelength range of 4.5 μ m-25 μ m. Low radiation coated glass can also be combined with solar control function, known as solar controlled low radiation glass. There are two main series of coated glass, one is online coated glass, also known as vapor phase evaporation coated glass. One type is offline coated glass, also known as magnetron sputtering coated glass. The characteristics of online vapor phase evaporation coated glass are long-lasting damage resistance and no production process limitations. It can undergo secondary processing such as tempering, cutting, and hot bending. There are no compatibility issues with Goering and seals. The characteristic of magnetron sputtering coated glass is its wide product performance and application range. The sputtering regulations require employees to have good operating habits. Edges need to be removed during the secondary processing. The sealant used in the synthesis of insulating glass must be compatible with the film. Tempered coated glass can be made from tempered glass, most of which cannot be directly used for tempering. Most of them cannot be processed elsewhere and must be processed into insulating glass as soon as possible after the production of coated glass is completed.

4. Hollow glass: Hollow glass is a product made by evenly separating two or more pieces of glass with effective supports and sealing them with adhesive around the edges, creating a dry gas space between the glass layers. At present, most of the insulated glass on the market is sealed with adhesive, which is divided into two methods: traditional aluminum strips and warm edge sealing.