SSAF Window Films Ltd

The ‘Invention’ of Laminate Glass

An accident led to the most popular ‘safety’ glass in use today…

In 1903 Edouard Benidictus was leaving his laboratory when he accidentally knocked over and broke a large glass jar, he must have thought nothing of it, and left it until the morning to clear up the resulting mess…

The glass jar was full of cellulose acetate and when Edouard tried to clear it up he noticed the glass was stuck fast to the contents of the jar, Seven years later a St. Gobain patent was issued to cover the idea. Development by companys called Dupont and Monsanto led to the extensive use of ‘laminate glass’ windscreens in cars and aircraft after the second world war.

Over the years of development, the original acetate has been replaced by ‘PolyVinyl Butyral’ or ‘PVB’ as the acetate used to turn brown, and go brittle with age, the PVB interlayer is the most common interlayer material used today.

Laminated glass is a ‘sandwich’ of two pieces of glass with the tough PVB interlayer bonded in between. The process involves heat and great pressure, but once the laminate is produced the layers act as a single unit, and look as normal glass. Annealed, toughened or tempered glass can be used as one or both of the laminates, as in modern car windscreens, to make a strong and versatile glass.