Are Black Dots on Your Windshield a Safety Concern?

Our automobiles have many parts that can be difficult to track or understand. As such, many questions and concerns arise for car owners. One commonly asked question is about the little black dots on car windshields that no one understands. Fortunately, the answer to this mystery is quite simple.

The black dots on your windshield are not dangerous at all, and their application is a necessary step in the manufacturing of any car, primarily serving as an adhesive between a car’s frame and its windshield. Take it from the best windshield repair service in Des Moines: these black dots are nothing to be afraid of!

What Are the Black Dots on My Windshield?

Those black dots and the black band to which they are attached are known as “frits” and are integral to car manufacturing. While frits may look purely decorative or even concerning to some, they are simply bits of ceramic paint baked into cars when built to secure windshields. 

Why Does My Windshield Have Little Dots: The Many Purposes of Frits

Like many automobile owners, you may wonder what the black dots on your windshield are and whether or not they are a safety concern. Luckily, quite the opposite is true. Frits serve a few significant purposes and are more than just spots of paint. 

Adhesion

The primary reason for the dots seen commonly on modern vehicles is to adhere your windshield to the rest of your car. Manufacturers bond the windshield and car frame with urethane adhesive during car manufacturing. Since the enamel has a rougher texture than glass, it bonds better to the urethane adhesive. This black enamel creates the black band and surrounding dots on a car windshield. Without frits, your windshield could loosen during drives. In this case, you should consult an automotive glass service. If you are looking for an auto glass company in Des Moines, Kryger Glass has you covered.

UV Radiation

Aside from adhesion, the black dots on your windshield behind your mirror protect the urethane sealant from ultraviolet radiation. According to an article from the National Library of Medicine, when exposed to UV radiation, the chemical bonds of urethane break down, causing its molecular weight to decrease and reduce the effectiveness of its mechanical features. This process is known as “dubbed photo-oxidative degradation” and can be a recipe for disaster when coupled with a car’s windshield.

Since darker colors absorb UV radiation, the black paint enamel used to create frits protects radiation from affecting the security of a windshield. By covering the adhesion, fritting also helps hold a car together.

Heat Distribution

Due to the frit band’s dark color, however, it can become hot as the temperature of its environment rises. When the frit heats in this manner, the temperature of the edges of the windshield glass also increases and becomes greater than that of the glass not in contact with the frit. This disparity creates an optical distortion called “lensing,” where a windshield begins to look deformed or melted. The array of dots spreading out of the black band on your windshield helps to distribute this heat more evenly throughout the glass, mitigating the possibility and intensity of lensing.

Aesthetics

Even with all this said, fritting still begs the question, “Why black dots?” The design of frits is intentional and often referred to as a “dot matrix,” a pattern of dots arranged in a specific way. In the case of windshield frits, the dots typically become smaller and further apart from one another as they get further from the edge of a windshield. At some point, the dots disappear altogether.

The purpose of this pattern is to make the transition from the black band of paint on the bottom of the windshield to the rest of the glass more seamless. Frits serve a purely aesthetic purpose along with many technical ones.

Keeping the Sun Out of Your Eyes

Aside from the black dots on the bottom of a windshield, another group of frits also tends to be behind a car’s rear-view mirror. This group of dots, called a “third visor frit,” blocks the sun from beaming through the space between sun visors. 

Frits are many things, but one thing they aren’t is scary. These little black dots significantly impact your car, keeping it intact and protecting the vehicle itself and its driver from the elements.