Laminated glass is one of the most widely used types of glass in vehicles. It is composed of two separate sheets of glass that are glued together with PVB (polyvinyl butyral) and then melted at high temperatures. Tempered glass is also commonly used in car doors or windows, and is often preferred for rear windshields due to its lower cost compared to laminated rear windshields. Automotive glass is either tempered or laminated.
The glass typically used for the rear window and the front and rear door windows are made of tempered glass, while the windshield is made of laminated glass. Tempered glass is created by treating it with rapid heating and cooling processes. This causes the tempered glass to break into small pieces that mimic the shape of pebbles when it breaks. Tempered glass is much stronger than before the tempering process, making it more difficult to break.
It is most commonly used in passenger windows of cars, while laminated glass forms the front and rear windshields most of the time. When tempered glass breaks, it is designed to break into small pieces that are less likely to cause additional injury or damage. Laminated glass, on the other hand, provides a cushioning effect when broken, as the pieces adhere to the adhesive rather than flying and increasing the chances of injury. Due to its unique non-shattering properties, laminated glass is the most widely used for windshield manufacturing.
It acts as a cushion and prevents passengers from being ejected from the car in the event of a head-on collision. Tempered glass is also safe, as it disintegrates into small pieces and blunt edged cubes rather than shards to protect passengers from damage. However, laminated glass can be repaired, while tempered glass breaks completely in an accident and requires a complete replacement. And since it does not provide any type of cushioning like laminated glass, it is only reserved for windows and not for windscreens.
Automotive glass is exceptionally durable and responsible for 60% of the car's structural integrity in rollover accidents, while absorbing 45% of the crash impact during a head-on collision. Laminated glass consists of two strong sheets of glass that become a single thick sheet by sandwiching a layer of polyvinyl butyral in between them. These layers are bonded together using high temperatures to provide us with an incredibly strong and durable automotive glass that won't break in the event of an accident. Laminated glass can be traced back to the 1920s, as two sheets of glass were placed together using a PVB (polyvinyl butyral) sheet between them.
