My assumption of a lack of post processes is because I come from a background of automotive refinishing and repair, where I’ve owned a shop and painted for many years along with getting into custom art graphics and airbrushing. The only finishes I know of that provide a similar durability are two part urethanes. Those are far too thick by comparison. When cutting into plastics that have been moulded, the finish shows no signs of mechanical layering or bonding like a post process finish in most cases. Often a cleanly broken or cut part shows a similar type of penetrating surface alteration I associate with a polishing operation, where the surface transitions in color and grain structure with in millimeter or few (in cases where the break is clean and does not appear to be influenced by stress alterations like ABS where it whitens under tension).
How does chromate conversion work with a prep regime and what kind of wet paint can offer similar durability to a 2k urethane when it is impossibly thin? Like I know the limitations of urethane well when it comes to corners and pointy bits where it will thin from surface tension. There is not a chance in hell that the buttons on the side of my phone could be painted with such a finish with an even conformal coating and remain durable for years of constant abrasion. Is there a name for this class and type of finish? Where are they sourced? What is the scale of the industry? Is there a way to access the process and products at a small scale?