Papers are coated to improve surface gloss, lustre, whiteness and printability. The coatings consist of natural pigments, a binder, and various process materials. The procedure is carried out on special coating machines in the paper mill. Coating can have many different effects, giving the paper a surface that ranges in appearance from very shiny (gloss enamel) to somewhat muted (satin velvet) to dull (matte). Cast-coated papers have a shiny mirrored surface achieved through drying on a hot, highly polished cylinder. Paper used to be coated right on the paper machine, which is why the umbrella term machine-coated paper is still used to mean coated offset, gravure, and letterpress stocks.
- Coated Paper