Laminated glass is composed of two or more pieces of glass, organic materials embedded in glued sandwiched between two layers of glass, the composite glass made by heat and pressure. Common glued layers of organic material for polyvinyl alcohol vinegar diaphragm (PVB film), PVB membrane has a special high performance, optical indicator of the diaphragm is very good, light transmission rate is above 90%, heat-resistance, cold resistance, impact resistance, elasticity, moisture resistance and aging resistance performance is good. Its refraction coefficient and glass are almost the same. The diaphragm in the over-50 ℃ does not harden, 130~140℃, have a good bonding properties at this temperature for glass with a high pressure press, the glass is securely bonded to the glue layer. Laminated glass with high strength, elasticity and resistance to penetration of the middle-tier, can withstand great impact, even if broken glass and debris still cling to the film, which has a high degree of security.