Reputedly the meanest, mattest, blackest acrylic black on the market:
This is one coat over a papier mache mask from The Works. It's still drying so there's some glossiness to bits of it but there's no denying it's black and it's matt:
Manufacturer's website:
http://stuartsemple.com/project/black-v1-0-beta-worlds-mattest-flattest-black-art-material/
John