The terms 'coated' and 'uncoated' are used in the Pantone Graphics guides to identify the color appearance based on what type of paper the ink is printed on. The colors are printed on coated and uncoated paper, referred to as Pantone ### C or Pantone ### U, such as Pantone 100 C or Pantone 100 U.

Coated paper has a shiny gloss coating, and the ink sits atop the coating allowing for minimal ink absorption. Uncoated paper has no surface coating permitting maximum ink absorption into the paper. The same Pantone color printed on coated and uncoated paper will have quite a different visual appearance. Although there is a variance in ink film thickness, the majority of the difference is attributed directly to the reaction of the ink to the paper.