He makes a lot of interesting paints and pigments, and is UK based.
https://culturehustle.com/collections/powder
I've bought a couple of versions of his blackest black paint, and one of his whitest white, and they've all be extraordinarily good.
I have some of his "LIT - THE WORLD'S GLOWIEST GLOW PIGMENT", but I haven't used it yet. I have no doubt it'll be great as well.
(I have a vague plan to paint a motorcycle in Black4.0 to see if it's unreflective enough to evade the IR laser speed detectors cops use here...)