When Was Bullet Proof Glass Invented


Bulletproof glass is one of those inventions that was created by mere accident, yet has changed the world in profound ways. When installed, people have a better way to be protected from those that might try to do them harm. It was so useful that when FDR went to make a speech about Pearl Harbor, he actually borrowed a vehicle from Al Capone because none of the Presidential vehicles had bulletproof glass in them.

The first version of laminated glass dates back to 1625, but a French chemist, Edouard Benedictus, is credited with the first bulletproof glass. The invention happened when Benedictus managed to drop one of his beakers that had been coated with a plastic nitrate. The beaker didn’t shatter and 6 years later, he had the first laminated glass patent in his hands. Here are some of his other inventions.

1. The Press Plate

After the invention of his reinforced glass, Benedictus looked to see what other uses his new glass could help to improve. One of his first attempts was an improved press plate, which could be used to attach virtually any flat items to other items so that the could be constructed in a better way. He saw his press plates being used to attach cushions to chairs or cork to felt, but virtually anything materials could be used in construction because of how strong the glass happened to be.

2. Manufacturing Processes for Glass

After discovering how the glass could be made to be stronger, Benedictus believed that it was important to patent the way that he actually strengthened the glass. There were a number of ways to strengthen glass at the time, including some limited lamination options, so it took 5 years of review for the patent office to actually return an approved application for his unique process. What made his methods different is that no solvents were being used to press the panes off glass together to create the stronger early versions of bulletproof glass.

3. Improved Glass

The earliest versions of laminated glass from Benedictus used a solvent to affix the laminate to the glass. Then a hydraulic press would be used to expel the solvent and seal the window so that it could be transparent. Soon after receiving his first patent, he realized that the economics of creating the stronger glass in this fashion wouldn’t be very feasible. He then developed a new solution that would be able to not only remove the solvents in an easy fashion, but also create curved, convex, or arched glass during the manufacturing process as well.

4. Windshields

One of the intended consequences of his accidental discovery was to find actual uses for his new glass that could be of value. In his research, Benedictus realized that the modern windshield could greatly benefit from the stronger glass. There would be no need to worry about impacts because the windshield on the vehicle would star or crack, but it would be very difficult for an impact to penetrate the vehicle itself with the laminate interior.

History of Bulletproof Glass