This is how glass impregnation works
Glass panels seem to have a completely smooth surface, but with electron microscopy, it looks different: Numerous craters are visible on the glass, where tiny dirt particles can settle as well as grease and lime.
A nano-seal compensates for these craters so that the dirt can no longer settle. In this way, the surface can be sealed, a beading occurs. This ensures that the disc does not get so dirty and easier to clean.
Use a nano-seal for your windshield: From about 70 km / h, the wind pressure will blow the water off your windshields.