You have probably noticed an area of your windshield “dotted” with small black dots. What is their use?
On the windshield of the car and also on the side windows of some models there are areas marked with rows of black dots. Their presence is not purely decorative. These brands have an important safety feature, which should not be overlooked.
The first reason for the presence of these points is actually aesthetic. Imagine a windshield that transitions from clear glass to a black frame in a clean border. That would be a bit strange, wouldn't it? The small dots create a smooth and gradual transition between the transparency of the windshield and the black border, thus giving a more harmonious appearance to the whole.
But the main reason behind these points is not just aesthetic. They also have a practical function. The black trim around the windshield, known as the "frit" or "frit band", helps protect the weather seal underneath from direct sunlight. Without this protection, the seal could quickly degrade under the effect of UV rays, causing water leaks inside the vehicle. The dots, in turn, further reduce the joint's exposure to the sun, gradually dispersing UV rays and reducing the amount of heat that reaches the joint.
Another important role of these points is heat dissipation. Glass can sometimes focus the sun's rays into a single point, much like a magnifying glass can light a fire when pointed toward the sun. The black dots help to disperse this concentration of heat, thus preventing the windshield from experiencing thermal stress which could weaken it or even cause it to crack. On newer models where these dots also appear behind the rearview mirror, the purpose is to provide additional protection against the sun's rays, as this area is not covered by the sun visors.
Finally, during the manufacture and installation of the windshield, these points also play a role. When the windshield is installed, it is glued to the bodywork with a special glue. The black dots create an area where this glue cannot be seen from the outside, allowing installers to work without having to worry about a perfect finish.
Black dots on our windshields are not just decorative elements. They have specific functions that aim to protect the car and guarantee the durability of the windshield. The next time you get into a car, take a moment to notice these little points and remember how important they are. They reflect a technology which, although discreet, is essential for our safety and comfort.