Description
The French chemist invented stratified glass in 1903 by pure chance.
It consists of two or more sheets of common or tempered glass, glued together by thin layers of plastic material, polyvinyl butyrate (PVB), which can be uncoloured and transparent or coloured, xerigrafato etc.. This last one provides good adhesion to glass and a high level of lengthening before breaking.
Laminated glass is very resistant to breaking; when it is hit, the break remains localised at the impact point.
The layer of PVB keeps the pieces of glass in place, reducing the risk of cuts caused by splinters and, also, absorbing the body's residual energy thereby preventing the body's entry through the glass, unless it is of a exceptional force.
In addition to PVB, other plastic materials are used as inserts.
Laminated glass is used as safety windows in windshields for cars, trains, airplanes etc.; in glass walls to resist any falls of people or things, but also as protection against vandalism and breaking and entering, as strengthened protection for art objects in museums in all the world and against explosions and bullet-shots (armoured glass).