Coating apparatus with donor surface, application device, and surplus extraction system

A coating apparatus and an endless donor surface, the donor surface having a Shore A hardness ranging from 60 to 80 and being movable so as to pass cyclically through the coating apparatus and the coating apparatus serving to coat the donor surface during each passage with a layer of metal or metal-looking particles for subsequent transfer of the particles from at least selected regions of the donor surface to a substrate, the coating apparatus comprising:

• a) a supply of particles suspended in a fluid that does not wet the donor surface, the particles adhering more strongly to the donor surface than to one another,
• b) an application device for applying the fluid to the donor surface in a manner to cause the particles suspended in the fluid to adhere to the surface, so as to form a substantially continuous particle coating on the donor surface, and
• c) a surplus extraction system operative to extract fluid and remove surplus particles that are not in direct contact with the surface so as to leave adhering to the donor surface, after each passage through the coating apparatus, a coating that is substantially only a single particle deep;
• wherein the fluid within which the particles are suspended is a liquid.