 Uncoated powders are generally less expensive and are based on natural food-grade starches typically derived from corn (maize), wheat, semolina, potato, tapioca and rice depending on the diameter required.Coated powders use the same range of raw materials but are encapsulated with a minuscule amount of natural coatings which enable the powders to flow freely though the spray guns on sheet-fed offset-litho printing presses.Enhanced versions of these coatings are used to give specific electrostatic (anti-static) and hydrophobic properties.