I think we`ve discussed this subject about road de-icers (salt, calcium chloride, magnesium chloride) and their binders (sugar beet juice) and how difficult the film from the binder is to remove with touch-less tunnel car washes. I know that there are some tunnel-wash chemicals developed in Europe specifically for this road traffic film (RTF), BUT they do not meet EPA specs for the USA, so they cannot be imported.
SO, I guess it`s a rinse-less wash via a wash medium that physically touches the paint to remove the road film AFTER going through a touch-less tunnel wash. This might be kind of hard to do when ambient temperatures are 20°F or colder when you do not have a heated garage or service area.
You know it`s Winter in Wisconsin when all the vehicles driven in this weather, regardless of color, turn "Ermine White".
(OK, I need to explain this term "Ermine White" The ermine is a small northern North American weasel whose brown and black fur coat turns pure white in the winter to provide a natural camouflage for their rodent hunting in the winter and protects them from winter predators like hawks, eagles, and owls. It reverts back to its brown and black fur colors in warmer weather).