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Car windshield mesh

I am trying to find out what the mesh-like material that is on the outside edge of the windshield on new cars, and what does it do? Thanks for any answers.

Are you talking about the dark speckled material that can be found at the top of the windshield, around the area where the rear view mirror mounts to the glass?
If you are, it is applied to the inside of the glass to filter out sun that can come in around the edges of the sunvisors.

However, based on your description (mesh on the outside of the windshield), I am not sure if I am interpreting your question correctly.

If you’re talking about that black band around the edge that turns into little chekerboard patterns, that’s a treated (coated) zone on the glass used by the manufacturer to bond to the unibody. If you’ll notice on new cars with windshield mirrors it also is extended down to a bonding square for the mirror assembly. I know not why they use this checked edge. I suspect it’s to make any assymetry less obvious.

that’s a treated (coated) zone on the glass used by the manufacturer to bond to the unibody.

I do not think this is correct. I believe the black edges are to keep the suns rays off the urethane adhesive to prevent failure of the urethane.

If I remember I will contact my glass supplier and ask them, post back later.

I always wondered how this area affected on-glass cell phone antennas (from the 80’s)

See this site
http://www.glassviewnews.com/article/article_1.php?page=long_disc&aid=35

Especially this statement:
“After laminating, the windshield is ready to be assembled with plastic moldings so it can be installed on the car. Known as glass encapsulation, this assembly process is usually done at the glass manufacturer. First, the peripheral section of the windshield is set in a predetermined position in a mold cavity. Next, molten plastic is injected into the mold; when it cools, it forms a plastic frame around the glass.”

Whether the purpose is ultimately adhesion, opacity for UV protection, or both, the zone is there for bonding to the unibody.

I read the article and I believe the encapsulation that it refers to is basically a reveal moulding that is part of the glass. When we have a car in the shop with a damaged reveal moulding that is actually encapsulated the only course of action there is would be replacement of the glass.

I called our supplier and asked them since they are experts. This is their explanation. The black border around the outside of the glass inner portion is called the “frit”. This frit serves as a barrier against UV rays to prevent degradation of the urethane adhesive. It also serves as a visual barrier so no one can see a squished bead of urethane.
The dot pattern serves as nothing more than a gradual transition from black to clear, it’s easy on the eyes. The wide band on top is a third visor.

I visited other sites as well, and believe the referenced “molding” includes the black areas. The windows are clearly shipped to the installers with the black on them, and that’s really the only step in the process that it could be applied. One other site I visited showed the black area more clearly, but the one in the link I provided also shows it.

The rest of the explanation works for me. That still makes it the “bonding area” in my mind, although I’m still not sure that enhanced adhesion isn’t also a reason for doing it.

I don’t really think our understandings of what it is are really that far different. The only difference is that I’m of the impression that adhesion is also a factor.

I don’t really think our understandings of what it is are really that far different.

Agreed. I bet if we were both standing in front of a piece of glass we would be talking about the same thing.

Thank you for all your answers. I knew if I posted the question here I would get my answer. Thank you to all. Stan

Agreed.

Happy motoring.