memes

Any department of transportation isn't going to have their own print department, as far as I know. They contract out print jobs like that since the equipment and expertise to produce at scale are prohibitively expensive for just one client. As I've seen, that kind of job uses laser-etched plates on rollers with different plates for each colour. Pantone inks, probably. So they need the laser machine, a printer the size of a small apartment, the licensing, and all the materials, just for signs.

The reflective coating is just a simple laminated layer.

Source: Worked at a printers and toured a couple screenprinting shops who had contracts with the city. We'd print anything as long as someone paid and sent the correct filetype.