Part 2: Windshield Glass

In our previous blog post, we learned that there are 3 main types of glass: annealed glass, tempered glass, and laminated glass. They are all manufactured through different processes to make them most suitable for their intended purposes. When it comes to your car’s windshields and windows, they have some pretty important purposes and functions.

We know how vital windshields are to overall vehicle safety:

So, yeah. Windshields are pretty darn important. And they can’t function up to their full potential if they aren’t strong and durable. So, what kind of glass is used to make windshields?


Windshield Glass = Laminated Glass.

In the past, many windshields were made of tempered glass. Tempered glass is considered a safety glass because when it shatters (yes, tempered glass does shatter), it breaks into very small pieces that have dull or more rounded edges. In the event of a motor vehicle accident, this helps protect passengers from additional injury from sharp glass fragments.

Modern windshields, however, are made from laminated glass. In fact, the US requires that all automobile and windshield manufacturers only use laminated glass for the windshields. This is the safest material for such an important part of the car. It’s stronger, more durable, and holds up to stress far better than tempered or annealed glass.


The Science Behind Laminated Windshield Auto Glass.

The windshield can only be as strong as the auto glass used to make it. Makes sense, right? The specialized glass designed for windshields are made up of a variety of different materials including: silica fine sand, soda ash, dolomite, cullet, and limestone. Sometimes, the glass also includes small amounts potassium oxide and aluminum oxide, but the primary ingredient is silica. The various substances found in glass all play a specific role in the process – some help reduce the melting point, others make the substances more pliable and easier to work with, and some help make the final product more durable. In the case of windshields, we want durable!

Laminated windshields are actually comprised of 3 layers. Think of it like a sandwich (yum!) – you have your 2 outer layers (the bread) and 1 middle layer (maybe you’re a ham and cheese person, or like the simplicity of PB&J, or maybe you like “fancy” sandwiches with a little bit of everything):

2 Outer Layers/aka the bread slices – these auto glass layers are made of tempered glass sheets

1 Middle Layer/aka the toppings – this auto glass layer is made up of a thin sheet of poly-vinyl butyral, most commonly known as PVB.

Once the sandwich is constructed (aka the 2 pieces of tempered glass being placed on different sides of the PVB layer), an autoclave heats up each component as pressure is applied. This process fuses all 3 layers together and helps them become the auto glass that provides the clarity and strength in the windshields we know and love today. As technology continues to advance, new components (ex: sensors that are utilized for Advanced Driver Assistance Systems, aka ADAS) are often added during this process to become part of the windshield itself. Read more about ADAS here, here, here, and here!!

Chipped or Cracked Windshield?

YOU want to be safe while driving.

WE want you to be safe while driving.

If you have a chipped or cracked windshield, or have sustained any other kind of windshield damage, call Auto Glass 2020 today at (480) 283-7751 or get a quote here. Any form of windshield damage needs to be assessed for windshield repair or windshield replacement to keep you and your loved ones safe while driving around this beautiful (and hot!) city of Phoenix, Arizona.